Taking and Importing Marine Mammals; Taking Marine Mammals Incidental to Construction and Operation of a Liquefied Natural Gas Deepwater Port in the Gulf of Mexico, 55645-55679 [2012-22092]

Download as PDF Vol. 77 Monday, No. 175 September 10, 2012 Part IV Department of Commerce mstockstill on DSK4VPTVN1PROD with PROPOSALS3 National Oceanic and Atmospheric Administration 50 CFR Part 217 Taking and Importing Marine Mammals; Taking Marine Mammals Incidental to Construction and Operation of a Liquefied Natural Gas Deepwater Port in the Gulf of Mexico; Proposed Rule VerDate Mar<15>2010 18:22 Sep 07, 2012 Jkt 226001 PO 00000 Frm 00001 Fmt 4717 Sfmt 4717 E:\FR\FM\10SEP3.SGM 10SEP3 55646 Federal Register / Vol. 77, No. 175 / Monday, September 10, 2012 / Proposed Rules DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration 50 CFR Part 217 [Docket No. 110801452–2387–03] RIN 0648–BB00 Taking and Importing Marine Mammals; Taking Marine Mammals Incidental to Construction and Operation of a Liquefied Natural Gas Deepwater Port in the Gulf of Mexico National Marine Fisheries Service (NMFS), National Oceanic and Atmospheric Administration (NOAA), Commerce. ACTION: Proposed rule; request for comments. AGENCY: NMFS has received a request from Port Dolphin Energy LLC (Port Dolphin) for authorization to take marine mammals incidental to port construction and operations at its Port Dolphin Deepwater Port in the Gulf of Mexico, over the course of five years; approximately June 2013 through May 2018. Pursuant to the Marine Mammal Protection Act (MMPA), NMFS is proposing regulations to govern that take and requests information, suggestions, and comments on these proposed regulations. DATES: Comments and information must be received no later than October 25, 2012. ADDRESSES: You may submit comments on this document, identified by FDMS Docket Number 110801452–2387–03, by any of the following methods: • Electronic Submission: Submit all electronic public comments via the Federal e-Rulemaking Portal www.regulations.gov. To submit comments via the e-Rulemaking Portal, first click the Submit a Comment icon, and then enter 110801452–2387–03 in the keyword search. Locate the document you wish to comment on from the resulting list and click on the Submit a Comment icon on the right of that line. • Hand delivery or mailing of comments via paper or disc should be addressed to Michael Payne, Chief, Permits and Conservation Division, Office of Protected Resources, National Marine Fisheries Service, 1315 EastWest Highway, Silver Spring, MD 20910. Comments regarding any aspect of the collection of information requirement contained in this proposed rule should be sent to NMFS via one of the means provided here and to the Office of mstockstill on DSK4VPTVN1PROD with PROPOSALS3 SUMMARY: VerDate Mar<15>2010 18:22 Sep 07, 2012 Jkt 226001 Information and Regulatory Affairs, NEOB–10202, Office of Management and Budget, Attn: Desk Office, Washington, DC 20503, OIRA@omb.eop. gov. Instructions: Comments must be submitted by one of the above methods to ensure that the comments are received, documented, and considered by NMFS. Comments sent by any other method, to any other address or individual, or received after the end of the comment period, may not be considered. All comments received are a part of the public record and will generally be posted for public viewing on www.regulations.gov without change. All personal identifying information (e.g., name, address) submitted voluntarily by the sender will be publicly accessible. Do not submit confidential business information, or otherwise sensitive or protected information. NMFS will accept anonymous comments (enter N/A in the required fields if you wish to remain anonymous). Attachments to electronic comments will be accepted in Microsoft Word, Excel, or Adobe PDF file formats only. FOR FURTHER INFORMATION CONTACT: Ben Laws, Office of Protected Resources, NMFS, (301) 427–8401. SUPPLEMENTARY INFORMATION: Availability A copy of Port Dolphin’s application may be obtained by writing to the address specified above (see ADDRESSES), calling the contact listed above (see FOR FURTHER INFORMATION CONTACT), or visiting the Internet at: http://www.nmfs.noaa.gov/pr/permits/ incidental.htm. To help NMFS process and review comments more efficiently, please use only one method to submit comments. Background Sections 101(a)(5)(A) and (D) of the MMPA (16 U.S.C. 1361 et seq.) direct the Secretary of Commerce to allow, upon request, the incidental, but not intentional, taking of small numbers of marine mammals by U.S. citizens who engage in a specified activity (other than commercial fishing) within a specified geographical region if certain findings are made and either regulations are issued or, if the taking is limited to harassment, a notice of a proposed authorization is provided to the public for review. Authorization for incidental takings shall be granted if NMFS finds that the taking will have a negligible impact on the species or stock(s), will not have an unmitigable adverse impact on the PO 00000 Frm 00002 Fmt 4701 Sfmt 4702 availability of the species or stock(s) for subsistence uses (where relevant), and if the permissible methods of taking and requirements pertaining to the mitigation, monitoring and reporting of such takings are set forth. NMFS has defined ‘‘negligible impact’’ in 50 CFR 216.103 as ‘‘* * * an impact resulting from the specified activity that cannot be reasonably expected to, and is not reasonably likely to, adversely affect the species or stock through effects on annual rates of recruitment or survival.’’ Except with respect to certain activities not pertinent here, the MMPA defines ‘‘harassment’’ as: ‘‘any act of pursuit, torment, or annoyance which (i) has the potential to injure a marine mammal or marine mammal stock in the wild [‘Level A harassment’]; or (ii) has the potential to disturb a marine mammal or marine mammal stock in the wild by causing disruption of behavioral patterns, including, but not limited to, migration, breathing, nursing, breeding, feeding, or sheltering [‘Level B harassment’].’’ Summary of Request On February 1, 2011, NMFS received a complete application from Port Dolphin for the taking of marine mammals incidental to port construction and operations at its Port Dolphin Deepwater Port (DWP) facility in the Gulf of Mexico (GOM). During the period of these proposed regulations (June 2013–May 2018), Port Dolphin proposes to construct the DWP and related infrastructure—expected to occur over an approximately 11-month period, beginning in June 2013—and to subsequently begin operations. The proposed DWP, which is designed to have an operational life expectancy of 25 years, would be an offshore liquefied natural gas (LNG) facility, located in the GOM approximately 45 km (28 mi) off the western coast of Florida, and approximately 68 km (42 mi) from Port Manatee, located in Manatee County, Florida, within Tampa Bay (see Figure S–1 in Port Dolphin’s application). The DWP would be in waters of the U.S. Exclusive Economic Zone (EEZ) approximately 31 m (100 ft) in depth. The proposed DWP would consist principally of a permanently moored buoy system, designed for offloading of natural gas, leading to a single proposed new natural gas transmission pipeline that would come ashore at Port Manatee and connect to existing infrastructure. Take of marine mammals would occur as a result of the introduction of sound into the marine environment during construction of the DWP and pipeline and during DWP operations, which would involve shuttle regasification E:\FR\FM\10SEP3.SGM 10SEP3 Federal Register / Vol. 77, No. 175 / Monday, September 10, 2012 / Proposed Rules mstockstill on DSK4VPTVN1PROD with PROPOSALS3 vessel (SRV) maneuvering, docking, and debarkation, as well as regasification activity. Because the specified activities have the potential to take marine mammals present within the action area, Port Dolphin requests authorization to incidentally take, by Level B harassment only, small numbers of bottlenose dolphin (Tursiops truncatus) and Atlantic spotted dolphin (Stenella frontalis). Description of the Specified Activity Port Dolphin proposes to own, construct, and operate a DWP in the U.S. EEZ of the GOM Outer Continental Shelf (OCS) approximately 45 km (28 mi) off the western coast of Florida to the southwest of Tampa Bay, in a water depth of approximately 31 m (100 ft). On March 29, 2007, Port Dolphin submitted an application to the U.S. Coast Guard (USCG) and the U.S. Maritime Administration (MarAd) for all federal authorizations required for a DWP license under the Deepwater Port Act of 1974 (DWPA). Port Dolphin received that license in October 2009. The Port would consist of a permanently moored unloading buoy system with two submersible buoys separated by a distance of approximately 5 km (3 mi). The buoys would be designed to moor a specialized type of LNG carrier vessel (i.e., SRVs) and would remain submerged when vessels are not present. Regasified natural gas would be sent out through the unloading buoy to a 36-in (0.9 m) pipeline that would connect onshore at Port Manatee with the existing Gulfstream Natural Gas System and Tampa Electric Company (TECO) Bayside pipeline. The DWP would only serve SRVs. Construction of the DWP would be expected to take 11 months. Port Dolphin DWP would be designed, constructed, and operated in accordance with applicable codes and standards and would have an expected operating life of approximately 25 years. The locations of the DWP and associated pipeline are shown in Figure S–1 in Port Dolphin’s application; Figure 1–1 of the same document depicts a conceptual site plan for the DWP. The installation of the DWP facilities would include the construction and installation of offshore buoys, mooring lines, and anchors. The two unloading buoys, also known as submerged turret loading (STL) buoys, would each have eight mooring lines connected to anchor points, likely consisting of piles driven into the seabed. When not connected to a SRV, STL buoys would be submerged 60 to 70 ft (18 to 21 m) below the sea surface. The installation of the pipeline VerDate Mar<15>2010 18:22 Sep 07, 2012 Jkt 226001 from the DWP to shore would include burial of the pipeline, selective placement of protective cover (either rock armoring or concrete mattresses) over the pipeline at several locations along the pipeline route where full burial is not possible, and the horizontal directional drilling (HDD) of three segments of the pipeline. SRVs are specialized LNG carriers designed to regasify the LNG prior to off-loading for transport to shore. Each STL buoy would moor one SRV on location throughout the unloading cycle. An SRV would typically moor at the deepwater port for between 4 and 8 days, depending on vessel size and send-out rate. Unloading of natural gas (i.e., vaporization or regasification) would occur through a flexible riser connected to the STL buoy and into the pipeline end manifold (PLEM) for transportation to shore via the subsea pipeline. With two separate STL buoys, Port Dolphin may schedule an overlap between arriving and departing SRVs, thus allowing natural gas to be delivered in a continuous flow. Port Dolphin is planning for an initial natural gas throughput of 400 million standard cubic feet per day (MMscfd). Although the Port would be capable of an average of 800 MMscfd with a peak capacity of 1,200 MMscfd, this level of throughput would not be achieved during the span of this proposed rule. Based on a regasification cycle of approximately 8 days and initial throughput of 400 MMscfd, maximum vessel traffic during operations over the lifetime of the proposed 5-year regulations is projected to consist of 46 SRV unloadings per year. In the open ocean, SRVs typically travel at speeds of up to 19.5 kn (36.1 km/hr). When approaching the vicinity of the DWP (i.e., during approach to the DWP), the SRVs would typically slow to about half speed. In close proximity to the STL buoys, the SRVs would slow to dead slow and utilize thrusters to attain proper vessel orientation relative to the DWP, taking into consideration ambient ocean currents, wind conditions, and buoy position. The following subsections describe the Region of Activity and the preceding facets of construction and operation in greater detail. Region of Activity The GOM is a marine water body bounded by Cuba on the southeast; Mexico on the south and southwest; and the U.S. Gulf Coast on the west, north, and east. The GOM has a total area of 564,000 km2 (217,762 mi2). Shallow and intertidal areas (water depths of less than 20 m) compose 38 percent of the PO 00000 Frm 00003 Fmt 4701 Sfmt 4702 55647 total area, with continental shelf (22 percent), continental slope (20 percent), and abyssal plain (20 percent) composing the remainder of the basin. The project site is located on the west Florida Shelf, a portion of the Inner Continental Shelf, in an area of relatively low wave energy and tidal variation (Gore, 1992). The GOM is separated from the Caribbean Sea and Atlantic Ocean by Cuba and other islands, and has relatively narrow connections to the Caribbean and Atlantic through the Florida and Yucatan Straits. The GOM is composed of three distinct water masses, including the North and South Atlantic Surface Water (less than 100 m deep), Atlantic and Caribbean Subtropical Water (up to 500 m deep), and Subantarctic Intermediate Water. Circulation within the GOM, and within the project area, is dominated by the Loop Current, which enters the GOM flowing north through the Yucatan Strait, flows south along the Florida coast in the vicinity of the project area, and exits the GOM through the Florida Straits. The velocity of the current in the project area ranges between 1.56 and 15.16 cm/s in summer, and 1.79 to 25.36 cm/s in winter (APL, 2006). The direction of flow in the project area is generally south to southeast. In shallow areas along the west Florida Shelf, additional influences on water flow and circulation include wind stress, freshwater inflow, and variations in buoyancy (Gore, 1992). Wind speeds at the project site range from 2.26 to 7.61 m/s in summer, and 2.85 to 11.04 m/s in winter (APL, 2006). Tidal variation along Florida’s west-central continental shelf is moderate, with an average range of approximately 2 ft (0.6 m) (Gore, 1992). At the eastern edge of the Loop Current along the west Florida Shelf, circulation patterns result in an upwelling of deep nutrient-rich water. This upwelling supports a high level of biological activity, producing large concentrations of plankton. Nutrient levels (primarily nitrogen and phosphorus) are also affected by runoff from agricultural and urbanized areas and from submarine groundwater discharge, leading to red tide conditions. In the project area, red tide occurs on an almost annual basis (Hu et al., 2006). Red tides are caused by rapid growth of the species Karenia brevis, a toxic species which produces brevetoxins (a type of neurotoxin) that can accumulate in bivalves and cause mortality in marine organisms (Hu et al., 2006). The rapid growth of these organisms can also create a hypoxic zone (area with dissolved oxygen E:\FR\FM\10SEP3.SGM 10SEP3 55648 Federal Register / Vol. 77, No. 175 / Monday, September 10, 2012 / Proposed Rules mstockstill on DSK4VPTVN1PROD with PROPOSALS3 concentrations below 2 mg/L), which can cause mortality among benthic communities, fish, turtles, birds, and marine mammals (Hu et al., 2006). Extreme variations in water circulation patterns, tides, and wave heights can occur along the west Florida coast during periodic tropical storms and hurricanes. Warm water within the Loop Current can act as an energy source in summer and fall months, fueling the development of these storms. Features of these storms that can affect natural circulation and topography include high winds, flooding, storm surges, and beach erosion. Tampa Bay is an estuary formed by the rise of sea level into a former river valley. Tampa Bay consists of four subregions, including lower Tampa Bay, middle Tampa Bay, Old Tampa Bay, and Hillsborough Bay. The project area would only extend to Port Manatee, within Lower Tampa Bay, near the outlet of the bay into the GOM. The bay covers an area of 1,030 km2 within Hillsborough, Manatee, and Pinellas counties. Freshwater inflow to the bay occurs through four major river systems (Alafia, Hillsborough, Little Manatee, and Manatee), as well as more than a hundred minor creeks and rivers. Water circulation within the bay is driven by freshwater inflow, tides, and winds. The bay has an average depth of 3.5 to 4 m. There is well-developed horizontal stratification in the bay, with fresh water flowing along the surface out to sea, and denser saline water flowing into the bay along the bottom. The Tampa Bay area has a population of more than two million people, and tributaries, habitat, runoff patterns, and water quality are all affected by urbanization. Specific actions that have affected the bay include removal of mangroves, dumping of sewage, artificial filling, and modification of runoff from paved surfaces (Peene et al., 1992). Dates of Activity Port Dolphin has requested regulations governing the incidental take of marine mammals for the fiveyear period from June 2013 through May 2018. Construction and installation of the port and pipeline would last approximately 11 months, with subsequent operations (i.e., SRV docking and regasification) occurring for the remainder of the specified time period. LNG and SRVs The DWPA establishes a licensing system for ownership, construction, and operation of deepwater ports in waters beyond the territorial limits of the VerDate Mar<15>2010 18:22 Sep 07, 2012 Jkt 226001 United States. Originally, the DWPA promoted the construction and operation of deepwater ports as a safe and effective means of importing oil into the United States and transporting oil from the OCS, while minimizing tanker traffic and associated risks close to shore. The Maritime Transportation Security Act of 2002 amended the definition of ‘‘deepwater port’’ to include facilities for the importation of natural gas. LNG is natural gas that has been cooled to about ¥260 °F (¥162 °C) for efficient shipment and storage as a liquid. LNG is more compact than the gaseous equivalent, with a volumetric differential of about 610 to 1. LNG can thus be transported long distances across oceans using specially designed ships (e.g., SRVs), allowing efficient access to stranded reserves of natural gas that cannot be transported by conventional pipelines. This proposed STL buoy system differs from other common LNG offload technologies insofar as it does not involve any permanent storage or regasification facility at the DWP, thus minimizing required infrastructure at the DWP itself. Rather, STL buoys receive SRVs that contain onboard LNG vaporization equipment. After mooring, LNG is vaporized onboard the vessel and discharged via the unloading buoy and a flexible riser into the subsea pipeline. Because the LNG is vaporized with the SRV’s onboard equipment, no permanent fixed or floating storage or vaporization facilities are required. However, this means that the offload process can take 5 to 8 days, as compared with a standard offload of 18 hours or less. As a result of this tradeoff, continuous off-loading operations are essential to minimize fluctuations in the throughput of natural gas. The SRVs proposed for use would be equipped to transport, store, vaporize, and meter natural gas. A closed-loop, glycol/waterbrine heat transfer system would be used to vaporize the LNG. Closed-loop systems burn vaporized LNG in order to heat an intermediate fluid (e.g., glycol/ water-brine), which warms the LNG. The closed-loop system results in reduced environmental impacts on water quality and marine resources; although these systems do require seawater for use in cooling electrical generating equipment (resulting in subsequent entrainment of fish eggs and plankton, as well as discharge of water at elevated temperatures), such usage is significantly reduced from that required in an open-loop system. SRVs with approximate cargo capacities of either 145,000 m3 or 217,000 m3 (189,653–283,825 yd3) PO 00000 Frm 00004 Fmt 4701 Sfmt 4702 based on standard designs for oceangoing LNG carriers would be used to supply LNG to the Port. Approximate dimensions of each SRV would range from 280 m (919 ft) in length and 43 m (141 ft) in breadth, with a design draft of 11.4 m (37.4 ft) for the smaller vessels to 315.5 m (1,035 ft) in length and 50 m (164 ft) in breadth, with a design draft of 12 m (39 ft) for the larger vessels. The maximum height above the waterline would be 41.1 m (135 ft). The 145,000 m3 SRV would displace 80,000 t (88,185 ton) and the 217,000 m3 SRV would displace 108,000 t (119,050 ton). The vessels would be equipped with a trunk and mating cone to receive the unloading buoy, lifting and connection devices, an LNG vaporization system, and gas metering systems. All critical functions would be manned 24 hours per day; other functions would be accomplished on a regular, scheduled basis. The SRVs would have two thrusters forward and could have one or two thrusters aft. Thrusters allow precise control of positioning while mooring with the STL buoy. The dynamic positioning system would be used while retrieving the submerged unloading buoy handling line and moving onto the buoy. The system normally would not be used while the SRV is moored to the unloading buoy. SRVs would be equipped with an acoustic position reporting system that would monitor the buoy’s draft and position before and during connection/disconnection; this would be enabled by six transponders located on the buoy itself. Seawater would be used to ballast the SRV, cool the dual-fuel diesel engines supplying power for the regasification process, and condense the steam produced by the boilers supplying heat to the vaporization process. Ballasting the SRV is required to maintain proper buoyancy as the LNG is vaporized and offloaded through the pipeline. Water intake for ballasting the SRV would require an average intake of 360 m3 per hour (2.3 MGD) over the vaporization cycle. The cooling water system would require an additional intake of approximately 1,520 m3 per hour (9.5 MGD) and would take in seawater through one of two sea chests, each measuring 1.5 x 2.0 m (4.9 x 6.6 ft). Water velocity through the lattice screens at the hull side shell would not exceed 0.15 m/s (0.49 ft/s) at the maximum flow rate of 1,520 m3 per hour. Cooling water discharges would be made at points removed from the intake sea chests to avoid recirculating warmed water through the cooling system. All of the cooling water would be discharged E:\FR\FM\10SEP3.SGM 10SEP3 Federal Register / Vol. 77, No. 175 / Monday, September 10, 2012 / Proposed Rules mstockstill on DSK4VPTVN1PROD with PROPOSALS3 at a temperature of approximately 10 °C (18 °F) above the ambient water temperature. Although the seawater system would be equipped with a chlorination system to prevent biofouling of heat transfer surfaces and system components, the chlorination system would not be used while the SRVs are approaching the Port or moored at the buoys. Port Construction In-water construction of Port Dolphin is expected to begin in June 2013 and last a total of approximately 11 months. Construction would include siting the STL buoys and associated equipment and laying the marine pipeline. Construction is assumed to be continuous from mobilization to demobilization with no work stoppages due to weather or other issues. Please see Table 2–1 of Port Dolphin’s application for a graphical depiction of the complete timeline of proposed construction activities. Port Dolphin anticipates that construction/ installation would be accomplished in the following sequence: • Install the Port Manatee HDD section, with installation proceeding from onshore to the offshore location. • Install the anchor piles and the mooring lines using the main installation vessel at the DWP. • Construction and installation of the HDD pipe sections for the segments under the existing Gulfstream pipeline. • Install seabed pipe segments between the Port Manatee HDD segment and the Gulfstream HDD segments. • Install the Skyway Bridge section of the pipe (requiring dredging through the causeway). • Install the STL Buoys. • Install the two risers from the PLEMs. • Install the north and south PLEMs. • Perform pipelay and diving operations towards the Y-connector. • Install the flowlines on the seafloor. • Complete tie-ins and bury or armor the pipeline, as necessary. • Conduct testing of the pipeline upon completion of burial operations. These components of in-water construction are discussed in greater detail in the following subsections. DWP Construction/Installation—As described previously, the Port would include two STL unloading buoy systems, separated by a distance of approximately 5 km (3.1 mi) in a water depth of approximately 31 m (100 ft). Each unloading buoy would have eight mooring lines, consisting of wire rope and chain, connecting to eight drivenpile anchor points on the sea floor, one 16-in (0.4-m) inside diameter flexible VerDate Mar<15>2010 18:22 Sep 07, 2012 Jkt 226001 pipe riser, and one electrohydraulic control umbilical from the unloading buoy to the riser manifold. When not connected to a SRV, STL buoys would be submerged 60 to 70 ft (18 to 21 m) below the sea surface. A concrete or steel landing pad would be fixed to the sea floor by means of a skirted mud mat to allow lowering of the STL buoy to the ocean floor when it is not in use. The mooring lines would be designed so that the SRV could remain moored in non-hurricane 100-year storm conditions, and would vary in length, from 1,800 to 4,000 ft (549 to 1,219 m) for the northern unloading buoy and from 2,500 to 3,600 ft (762 to 1,097 m) for the southern buoy. The mooring lines would consist of 132-mm (5.2-in) chain and 120-mm (4.7-in) spiral-strand wire rope. The riser system for each unloading buoy would consist of one 16-in interior diameter flexible riser in a steep-wave configuration. Total length of the riser would be approximately 82 m (269 ft). The riser would be directed between two of the mooring lines, and would lie on the seafloor when not in use. The two PLEMs near the unloading buoys would connect the flexible risers to the flowlines and a Y-connection that would connect the two flowlines to the new gas transmission pipeline. Each of the two PLEMs would be approximately 75 m (246 ft) offset from the proposed unloading buoy locations. The purpose of a PLEM is to provide an interface between the pipeline system and the flexible riser, isolate the riser between gas unloading operations, and attach a subsea pig launcher or receiver as necessary. ‘‘Pigs,’’ or ‘‘pipeline inspection gauges,’’ travel remotely through a pipeline to conduct inspections of or clean the pipeline and collect data about conditions in the pipeline. Each PLEM would include a flange connection for attaching the flexible riser or the subsea pig launcher/ receiver and a full-bore subsea hydraulic control valve and electrohydraulic umbilical termination assembly. Each PLEM would have a mud mat foundation to provide a stable base for bearing PLEM and riser weight and to resist sliding and overturning forces. Please see Figure 1–1 in Port Dolphin’s application for a conceptual diagram of the DWP. Offshore installation activities at the DWP would begin with installation of the PLEMs at both STL buoy locations (north and south), followed by placement of the buoy anchors, mooring lines, buoys, and risers. Installation activities at both STL buoy locations would require a cargo barge, supported by anchor-handling support vessels, a PO 00000 Frm 00005 Fmt 4701 Sfmt 4702 55649 supply boat, a crew transfer boat, and a tug. Buoy anchors would likely be installed via impact pile driving. Pipeline Installation—The pipeline would be laid on the seafloor by a pipelaying barge and then buried, typically using a plowing technique. Other techniques, such as dredging and HDD, are planned to be used in certain areas depending on the final geotechnical survey, engineering considerations, and equipment selection. At the western (seaward) end, the pipeline would consist of two 36-in (0.9-m) flowlines connected to the north and south PLEMs, which would connect at a Y-connection approximately 3.2 km (2 mi) away (see Figure 1–1 in Port Dolphin’s application). From the Yconnection a 36-in (0.9-m) gas transmission line would travel approximately 74 km (46 mi) to interconnections with the Gulfstream and TECO pipeline systems. The pipelines would have a nominal outer diameter of 36 in, with a coating of fusion-bonded epoxy and a concrete weight coating thickness of 11.4 cm (4.5 in). Pipeline trenching and burial requirements are governed by Department of the Interior regulations at 30 CFR 250 Subpart J, which requires pipelines and all related appurtenances to be protected by 3 ft (0.9 m) of cover for all portions in water depths less than 200 ft (61 m). Portions of the pipeline that travel through hard-bottom areas may not be able to be buried to the full 3 ft depth. In these areas, flexible concrete mattresses or other cover would be used to cover the pipeline. In places where the pipeline crosses shipping lanes, it would be buried 10 ft (3 m) deep if the sea floor permits plowing. Burying the pipeline and flowlines would protect them from potential damage from anchors and trawls and avoid potential fouling, loss, or damage of fishermen’s trawls. The pipeline construction corridor would be 3,000 ft (914 m) wide in offshore areas. The permanent in-water right-of-way for the pipeline would be 200 ft (61 m) wide. Under the plowing method, the pipeline is lowered below seabed level by shearing a V-shaped ditch underneath it. The plow is towed along and underneath the pipeline by the burial barge. As the ditch is cut, sediment is removed and passively pushed to the side by specially shaped moldboards that are fitted to the main plowshare. The trench is then backfilled with a subsequent pass of the plow. The estimated width of the trench (including sediments initially pushed to each side) is 67 ft (20.4 m) (see Figure 1–2 in Port E:\FR\FM\10SEP3.SGM 10SEP3 55650 Federal Register / Vol. 77, No. 175 / Monday, September 10, 2012 / Proposed Rules mstockstill on DSK4VPTVN1PROD with PROPOSALS3 Dolphin’s application for a conceptual diagram of this process). In areas that cannot be plowed (e.g., due to hard/live bottom) or complete burial cannot be achieved, the pipeline would be covered with an external cover (e.g., concrete mattresses or rock armoring). Although plowing is the preferred methodology for pipeline burial, other techniques such as dredging and HDD would be used where required. Figure 1–3 of Port Dolphin’s application uses color coding of the proposed pipeline route to show where these various methodologies would be used, based on bottom structure and other barriers. The total length of the pipeline route is 74 km. Burial techniques to be used along the pipeline route and their relative lengths are characterized as follows: • Plowing/trenching soft sediments: 39.6 km (24.6 mi; 53.2 percent of total pipeline length); • Plowing/external cover: 23.3 km (14.5 mi; 31.4 percent); • External cover (concrete mattress/ rock armoring): 8.5 km (5.3 mi; 11.7 percent); • Clamshell dredging/dragline burial: 0.3 km (0.2 mi; 0.5 percent); and • HDD: 2.4 km (1.5 mi; 3.2 percent). HDD would be employed for installation of the pipeline at three locations along the inshore portion of the route. The proposed HDD locations include drilling from land to water at the Port Manatee shore approach and from water-to-water at two crossings of the existing Gulfstream pipeline. The eastern HDD crossing would be 898 m (2,947 ft) in length, and the western HDD crossing would be 407 m (1,335 ft) in length. Both crossings would be in a water depth of 6.4 m (21 ft). The Port Dolphin pipeline would be drilled to a depth of approximately 6 m (20 ft) below the existing Gulfstream Pipeline (Port Dolphin, 2007b). HDD is a steerable method of installing pipelines underground along a prescribed bore path, with minimal impact on the surrounding area. The process starts with location of entry and exit points. The first stage drills a pilot hole on the designed path, and the second stage enlarges the hole by passing a larger cutting tool known as a reamer. This would involve using progressively larger drill strings to eventually produce a drill bore 48 in (1.22 m) in diameter. The third stage places the product or casing pipe in the enlarged hole by way of the drill steel and is pulled behind the reamer to allow centering of the pipe in the newly reamed path. Simultaneously, bucket dredging would be employed to produce an exit hole at the end of the bore. Inwater HDD may involve significant distance between the seabed and the drilling rig, and so a casing pipe may be required during the initial pilot hole drilling to provide some rigidity to the drill pipe as it is pushed ahead by the rig. Structures known as ‘‘goal posts’’ provide support for the casing pipe and are typically comprised of two driven piles with cross members set at predetermined elevations. Port Dolphin has identified the need to install goal posts as part of the HDD drilling effort at the two water-to-water HDD locations. One potential option is that the goal posts are designed to selfinstall; however, another option is that drilling may be required. Further, at the shore-to-water transition HDD, Port Dolphin would need to install sheet piling to form a coffer dam, designed to contain the HDD exit pit so as to not impact nearby aquatic vegetation. Sheet pile segments would be installed by vibratory means. Clam shell dredging would be required for passage under the Skyway Bridge and would be performed from a fixed working platform. Although dredging, followed by conventional lay and bury, is the most likely scenario, HDD remains a possibility for this segment. In the area near Manbirtee Key, a flotation ditch—dredging operations may require such a ditch when the minimum water depth necessary to safely float equipment is not present—would be dredged using conventional dredging equipment (i.e., the same barge that would be used to pull-in the shore approach HDD). The anticipated locations where the various methods of pipeline installation would be used are shown in Figure 1–3 of Port Dolphin’s application. There are eleven locations where tiein operations would be required to piece the pipeline sections together. This mechanical operation is accomplished with specially designed connectors and a manned diving rig. This common operation does not require welding. Tieins would be required at each end of all HDD crossings, the Y-connection, and the PLEMs. Construction Vessels—A shallowwater lay barge, spud barge and clamshell dredge, and a jack-up barge would be mobilized for offshore pipelaying activities. Jack-up barges are mobile work platforms that are fitted with long support legs that can be raised or lowered; upon arrival at the work location the legs would be lowered and the barge itself raised above the water such that wave, tidal and current loading acts only on the relatively slender legs and not on the barge hull. A spud barge is a type of jack-up barge that typically offers increased stability but does not raise the hull above the water. This equipment would be used where conventional installation methods are anticipated. An HDD spread, including four jack-up barges, three hopper barges (designed to carry materials), and two tugs for barge towing, would be used for the three planned HDD segments. Four diving support vessels would also support tiein and mattressing operations. Construction equipment would make one round-trip to the project location, staying on location for the duration of construction activity. Work crew vessels and supply vessels would make on average two trips a day for the duration of offshore construction. Work crew and supply vessels are expected to make between 420 and 450 round-trips to the offshore construction location from shore-based facilities for the duration of the project. Table 1 details the vessels that would be used during the DWP and pipeline construction and installation activities. The projected duration and duty load of each vessel are also provided. Duty load is a primary consideration when characterizing project-related sound sources. TABLE 1—VESSELS TO BE EMPLOYED DURING PORT DOLPHIN CONSTRUCTION AND/OR FACILITY INSTALLATION OPERATIONS Operation Auxiliary equipment/notes Engine specifications 1 Operational usage 2 N/A ............................. 2 × 3,750-hp. 3.5 months at 100%. Construction/Installation at DWP Barge ................................................................ Anchor-handling support vessels ..................... Supply boat ...................................................... VerDate Mar<15>2010 18:22 Sep 07, 2012 Jkt 226001 ......................................................................... ROV winches, hydraulic pumps, thrusters, sonar, survey equipment. Bow thruster .................................................... PO 00000 Frm 00006 Fmt 4701 Sfmt 4702 671-hp. E:\FR\FM\10SEP3.SGM 10SEP3 Federal Register / Vol. 77, No. 175 / Monday, September 10, 2012 / Proposed Rules 55651 TABLE 1—VESSELS TO BE EMPLOYED DURING PORT DOLPHIN CONSTRUCTION AND/OR FACILITY INSTALLATION OPERATIONS—Continued Operation Auxiliary equipment/notes Engine specifications 1 Operational usage 2 Crew transfer boat ............................................ Tug ................................................................... Impact hammer ................................................ ......................................................................... ......................................................................... ......................................................................... 671-hp. 800-hp. N/A ............................. As required. Jack-up ............................................................ Tug .................................................................. 3,000-hp ..................... 1,200-hp ..................... 27 days at 50%. 59.4 days at 75%. Tug .................................................................. Jack-up ............................................................ Jack-up ............................................................ Jack-up ............................................................ Jack-up ............................................................ Tug .................................................................. 1,200-hp. 3,000-hp ..................... 3,000-hp. 3,000-hp ..................... 3,000-hp. 2,000-hp ..................... Tug .................................................................. ......................................................................... Tug .................................................................. 2,000-hp. 600-hp ........................ 2,000-hp ..................... Tug .................................................................. Vessel ............................................................. Vessel ............................................................. Vessel ............................................................. ......................................................................... Vessel ............................................................. ......................................................................... Vessel ............................................................. ......................................................................... Vessel ............................................................. ......................................................................... Vessel ............................................................. Vessel ............................................................. Tug .................................................................. 2,000-hp. 1,000-hp ..................... 1,000-hp. 1,000-hp ..................... 1,000-hp. 1,000-hp. 1,000-hp. 300-hp ........................ 300-hp. 300-hp. 300-hp. 1,000-hp ..................... 1,000-hp. 1,200-hp ..................... Tug .................................................................. Jack-up ............................................................ Jack-up ............................................................ Jack-up ............................................................ Jack-up ............................................................ Tug .................................................................. 1,200-hp. 2,000-hp ..................... 2,000-hp. 2,000-hp ..................... 2,000-hp. 2,000-hp ..................... Tug .................................................................. Barge ............................................................... Tug .................................................................. 2,000-hp. 600-hp ........................ 2,000-hp ..................... Tug .................................................................. Vessel ............................................................. ......................................................................... Vessel ............................................................. ......................................................................... Vessel ............................................................. ......................................................................... Vessel ............................................................. ......................................................................... Vessel ............................................................. 2,000-hp. 1,000-hp ..................... 1,000-hp. 1,000-hp. 1,000-hp. 300-hp ........................ 300-hp. 300-hp. 300-hp. 1,000-hp ..................... Pipeline installation Jack-up: Port Manatee HDD ............................ Spud lay barge: Shallow lay operation; no propulsion; uses two tugs. East jack-ups .................................................... West jack-ups ................................................... Pipelay barge: Large lay barge operation; no propulsion; uses two tugs. Dragline barge .................................................. Plow lay barge: Plow burial operation; no propulsion; uses two tugs. DSVs for mattress armoring ............................. DSVs for mattress armoring ............................. Pipeline gauge, fill, test, dewater, and drying .. Survey vessel ................................................... Spud lay barge: Shallow lay barge operation; no propulsion; uses two tugs. East jack-ups .................................................... West jack-ups ................................................... Pipelay barge: Large lay barge operation; no propulsion; uses two tugs. Dragline barge .................................................. Plow lay barge: Plow burial operation; no propulsion; uses two tugs. DSVs for mattress armoring ............................. Pipeline gauge, fill, test, dewater, and drying .. Survey vessel ................................................... 27 days at 75%. 27 days at 75%. 37 days at 85%. 6 days at 100%. 113 days at 85%. 108 days at 100%. 12 days at 15%. 13 days at 35%. 54 days at 50%. 6.6 days at 15%. 3 days at 15%. 3 days at 15%. 4 days at 15%. 1 day at 15%. 13 days at 15%. 12 days at 15%. 1 day at 15%. 6 days at 15%. mstockstill on DSK4VPTVN1PROD with PROPOSALS3 HDD operations Jack-up: Port Manatee HDD ............................ Spud barge ....................................................... Tug ................................................................... Jack-up ............................................................ Crane-mounted drill and vibratory drill; ancillary equipment includes welding equipment, air compressor, and generator. ......................................................................... 3,000-hp ..................... N/A ............................. 800-hp ........................ DSV = Diving spread vessels 1 All specifications are for diesel engines. 2 All figures assume 24 hrs/day; percentages refer to percent maximum duty load. VerDate Mar<15>2010 18:22 Sep 07, 2012 Jkt 226001 PO 00000 Frm 00007 Fmt 4701 Sfmt 4702 E:\FR\FM\10SEP3.SGM 10SEP3 3 days at 15%. Maximum 4 days for vibratory drilling at each HDD location. Maximum 4 days for vibratory drilling at each HDD location. 55652 Federal Register / Vol. 77, No. 175 / Monday, September 10, 2012 / Proposed Rules Port Operations The proposed DWP operations would include SRV maneuvering/docking, regasification of LNG cargo, and debarkation. The SRVs are expected to approach the DWP from the south. In the open ocean, the SRVs typically travel at speeds of up to 19.5 kn (36.1 km/hr), reducing to less than 14 kn (25.9 km/hr) while maintaining full maneuvering speed. However, once approaching the vicinity of the DWP— within approximately 16 to 25 km (10– 16 mi) of the DWP—the SRVs would begin approach by slowing to about half speed, and then to slow ahead. Inside of 5 km (3.1 km) from the DWP, the SRVs’ main engines would be placed in dead slow ahead and decreased upon approach to dead slow, with final positioning and docking to occur using thrusters. Expected SRV transit, approach, and maneuvering/docking characteristics are outlined in Table 2. Only the maneuvering/docking activities and their associated sound sources (i.e., thrusters) are considered in this document; transit and approach maneuvers are considered part of routine vessel transit and are not considered further. TABLE 2—SRV SPEEDS AND THRUSTER USE DURING TRANSIT, APPROACH, AND MANEUVERING/DOCKING OPERATIONS AT THE DWP Zone Speed limit Thrusters in use? >33 km from DWP .............................. 25–33 km from DWP .......................... 16–25 km from DWP .......................... 5–16 km from DWP ............................ Inside 5 km from DWP ....................... Docking ............................................... Full service speed (19.5 kn) ............................................ Full maneuvering speed (<14 kn) ................................... Half ahead (<10 kn) ........................................................ Slow ahead (<6 kn) ......................................................... Dead slow ahead (<4.5 kn, decreasing to <3 kn) .......... Dead slow ........................................................................ No No No No Bow and stern thrusters Two bow thrusters; possibly one or two stern thrusters Based on a regasification cycle of approximately 8 days and projected DWP throughput during the first several years of 400 MMscfd, vessel traffic during operations is projected to consist of a maximum of 46 SRV trips per year. During DWP operations, sound would be generated by the maneuvering of SRVs upon approach to the Port, regasification of LNG aboard the SRVs, and subsequent debarkation from the Port. Once an SRV is connected to a buoy, the vaporization of LNG and send-out of natural gas can begin. Each SRV would be equipped with up to five vaporization units, each with the capacity to vaporize 250 MMscfd. Under normal operation, two or more units would be in service simultaneously, with at least one unit on standby mode. TABLE 3—PROJECTED CONSTRUCTION, sound would be created by propulsion INSTALLATION, AND OPERATIONS AC- machinery, thrusters, generators, and hull vibrations and would vary with TIVITIES, BY SEASON Activity Season Construction and installation Buoy installation ........ Offshore impact hammering. Pipelaying offshore ... Pipelaying inshore ..... Offshore pipeline burial. Inshore pipeline burial HDD .......................... HDD vibratory driving Summer 2013 Summer 2013 Late Summer 2013 through early Winter 2013–14 Late Summer 2013 through early Winter 2013–14 Fall 2013 through Winter 2013–14 Fall 2013 through Winter 2013–14 Summer 2013 Summer 2013 Operations mstockstill on DSK4VPTVN1PROD with PROPOSALS3 Method of Incidental Taking Incidental take is anticipated to result from elevated levels of sound introduced into the marine environment by the construction and operation of the DWP, as described in preceding sections. Specifically, sound from pile driving, drilling, dredging, and vessel operations during the construction and installation phase, and sound from SRV maneuvering, docking, and regasification during operations would likely result in the behavioral harassment of marine mammals present in the vicinity. Table 3 shows these proposed activities by the time of year they are anticipated to occur. VerDate Mar<15>2010 18:22 Sep 07, 2012 Jkt 226001 SRV maneuvering/ docking. Regasification ............ Year-round; maximum 46 visits per year Year-round; 8 days estimated per visit During construction, underwater sound would be produced by construction vessels (e.g., barges, tugboats, and supply/service vessels) and machinery (e.g., pile driving and pipe laying equipment, trenching equipment, and goal post installation equipment at the HDD locations) operating either intermittently or continuously throughout the area during the construction period. Vessel traffic associated with construction would be a relatively continuous sound source during the construction phase. Vessel PO 00000 Frm 00008 Fmt 4701 Sfmt 4702 vessel and engine size. Machinery sound from underwater construction would be transmitted through water and would vary in duration and intensity. Port construction (i.e., field construction and installation operations) would require approximately 11 months. While the main sound source during SRV transit and approach to the DWP would originate from the SRV main engines (i.e., predominantly in low frequencies), the primary sound source during maneuvering and docking would be the SRV thrusters. An additional underwater sound source would be the sound produced by the flow of gas through the proposed pipeline, although very little sound would be expected to result (JASCO, 2008); therefore, this source is not considered further. Description of Sound Sources Sound travels in waves, the basic components of which are frequency, wavelength, velocity, and amplitude. Frequency is the number of pressure waves that pass by a reference point per unit of time and is measured in hertz (Hz) or cycles per second. Wavelength is the distance between two peaks of a sound wave; lower frequency sounds have longer wavelengths than higher frequency sounds, which is why the lower frequency sound associated with the proposed activities would attenuate more rapidly in shallower water. Amplitude is the height of the sound pressure wave or the ‘‘loudness’’ of a sound and is typically measured using the decibel (dB) scale. A dB is the ratio E:\FR\FM\10SEP3.SGM 10SEP3 Federal Register / Vol. 77, No. 175 / Monday, September 10, 2012 / Proposed Rules between a measured pressure (with sound) and a reference pressure (sound at a constant pressure, established by scientific standards), and is a logarithmic unit that accounts for large variations in amplitude; therefore, relatively small changes in dB ratings correspond to large changes in sound pressure. When referring to sound pressure levels (SPLs; the sound force per unit area), sound is referenced in the context of underwater sound pressure to 1 microPascal (mPa). One pascal is the pressure resulting from a force of one newton exerted over an area of one square meter. The source level (SL) represents the sound level at a distance of 1 m from the source (referenced to 1 mPa). The received level is the sound level at the listener’s position. Root mean square (rms) is the quadratic mean sound pressure over the duration of an impulse. Rms is calculated by squaring all of the sound amplitudes, averaging the squares, and then taking the square root of the average (Urick, 1975). Rms accounts for both positive and negative values; squaring the pressures makes all values positive so that they may be accounted for in the summation of pressure levels (Hastings and Popper, 2005). This measurement is often used in the context of discussing behavioral effects, in part because behavioral effects, which often result from auditory cues, may be better expressed through averaged units than by peak pressures. When underwater objects vibrate or activity occurs, sound-pressure waves are created. These waves alternately compress and decompress the water as the sound wave travels. Underwater sound waves radiate in all directions away from the source (similar to ripples on the surface of a pond), except in cases where the source is directional. The compressions and decompressions associated with sound waves are detected as changes in pressure by aquatic life and man-made sound receptors such as hydrophones. The underwater acoustic environment consists of ambient sound, defined as environmental background sound levels lacking a single source or point (Richardson et al., 1995). The ambient underwater sound level of a region is defined by the total acoustical energy being generated by known and unknown sources, including sounds from both natural and anthropogenic sources. These sources may include physical (e.g., waves, earthquakes, ice, atmospheric sound), biological (e.g., sounds produced by marine mammals, fish, and invertebrates), and anthropogenic sound (e.g., vessels, dredging, aircraft, construction). Even in the absence of anthropogenic sound, the sea is typically a loud environment. A number of sources of sound are likely to occur within Tampa Bay and the adjoining shelf, including the following (Richardson et al., 1995): • Wind and waves: The complex interactions between wind and water surface, including processes such as breaking waves and wave-induced bubble oscillations and cavitation, are a 55653 main source of naturally occurring ambient sound for frequencies between 200 Hz and 50 kHz (Mitson, 1995). In general, ambient sound levels tend to increase with increasing wind speed and wave height. Surf sound becomes important near shore, with measurements collected at a distance of 8.5 km (5.3 mi) from shore showing an increase of 10 dB in the 100 to 700 Hz band during heavy surf conditions. • Precipitation sound: Sound from rain and hail impacting the water surface can become an important component of total sound at frequencies above 500 Hz, and possibly down to 100 Hz during quiet times. • Biological sound: Marine mammals can contribute significantly to ambient sound levels, as can some fish and shrimp. The frequency band for biological contributions is from approximately 12 Hz to over 100 kHz. • Anthropogenic sound: Sources of ambient sound related to human activity include transportation (surface vessels and aircraft), dredging and construction, oil and gas drilling and production, seismic surveys, sonar, explosions, and ocean acoustic studies (Richardson et al., 1995). Shipping sound typically dominates the total ambient sound for frequencies between 20 and 300 Hz. In general, the frequencies of anthropogenic sounds are below 1 kHz and, if higher frequency sound levels are created, they would attenuate (decrease) rapidly (Richardson et al., 1995). Typical SPLs for various types of ships are presented in Table 4. TABLE 4—UNDERWATER SPLS FOR REPRESENTATIVE VESSELS Vessel description Frequency (Hz) Outboard drive; 23 ft; 2 engines @ 80 hp .............................................................................. Twin diesel; 112 ft ................................................................................................................... Small supply ships; 180–279 ft ............................................................................................... Freighter; 443 ft ....................................................................................................................... 630 630 1,000 41 Source level (dB) 156 159 125–135 (at 50 m) 172 mstockstill on DSK4VPTVN1PROD with PROPOSALS3 Source: Richardson et al., 1995. The sum of the various natural and anthropogenic sound sources at any given location and time—which comprise ‘‘ambient’’ or ‘‘background’’ sound—depends not only on the source levels (as determined by current weather conditions and levels of biological and shipping activity) but also on the ability of sound to propagate through the environment. In turn, sound propagation is dependent on the spatially and temporally varying properties of the water column and sea VerDate Mar<15>2010 18:22 Sep 07, 2012 Jkt 226001 floor, and is frequency-dependent. As a result of the dependence on a large number of varying factors, the ambient sound levels at a given frequency and location can vary by 10–20 dB from day to day (Richardson et al., 1995). Very few measurements of ambient sound from Tampa Bay and the adjoining shelf are available. There are no specific data on ambient underwater sound levels for the area of the proposed Port and pipeline route. Shooter et al. (1982) analyzed approximately 12 hours of data collected in deep (3,280 m) PO 00000 Frm 00009 Fmt 4701 Sfmt 4702 waters in the western GOM and reported median ambient sound levels of 77–80 dB re: 1 mPa2/Hz. These levels are likely to be somewhat lower than those occurring in the vicinity of Tampa Bay, due in large part to the reduced contribution from surf in deep water. Known sound levels and frequency ranges associated with anthropogenic sources similar to those that would be used for this project are summarized in Table 5. Details of each of the sources are described in the following text. E:\FR\FM\10SEP3.SGM 10SEP3 55654 Federal Register / Vol. 77, No. 175 / Monday, September 10, 2012 / Proposed Rules TABLE 5—ANTICIPATED SOURCE LEVELS FOR CONSTRUCTION/INSTALLATION AND OPERATIONS AT THE PORT DOLPHIN DWP Source Activity Location Barge ........................ Tug ........................... Impact hammer 1 ...... Barge ........................ Tug ........................... Dredge ...................... HDD .......................... Vibratory driving ....... SRV .......................... SRV .......................... Anchor installation operations ................................. Anchor installation operations ................................. Pile driving ............................................................... Pipe laying ............................................................... Transit ..................................................................... Dredging .................................................................. Drilling ..................................................................... Sheet pile installation .............................................. Maneuvering/docking, with thrusters ...................... Regasification .......................................................... STL buoys (DWP) ................................................... STL buoys (DWP) ................................................... STL buoys (DWP) ................................................... Pipeline corridor, DWP to shore ............................. Offshore/Inshore ...................................................... Likely inshore, offshore if necessary ...................... Two locations in Tampa Bay .................................. Two locations in Tampa Bay .................................. DWP ........................................................................ DWP ........................................................................ Maximum broadband source level (re: 1 μPa) 177 205 217 174 191 188 157 186 183 165 dB dB dB dB dB dB dB dB dB dB mstockstill on DSK4VPTVN1PROD with PROPOSALS3 Source: JASCO, 2008, 2010. 1 Source level for impact hammer estimated assuming pulse length of 100 ms. The sounds produced by these activities fall into one of two sound types: Pulsed and non-pulsed (defined in next paragraph). The distinction between these two general sound types is important because they have differing potential to cause physical effects, particularly with regard to hearing (e.g., Ward, 1997 in Southall et al., 2007). Please see Southall et al. (2007) for an in-depth discussion of these concepts. Pulsed sounds (e.g., explosions, gunshots, sonic booms, impact pile driving) are brief, broadband, atonal transients (ANSI, 1986; Harris, 1998) and occur either as isolated events or repeated in some succession. Pulsed sounds are all characterized by a relatively rapid rise from ambient pressure to a maximal pressure value followed by a decay period that may include a period of diminishing, oscillating maximal and minimal pressures. Pulsed sounds generally have an increased capacity to induce physical injury as compared with sounds that lack these features. Non-pulse (intermittent or continuous) sounds can be tonal, broadband, or both. Some of these nonpulse sounds can be transient signals of short duration but without the essential properties of pulses (e.g., rapid rise time). Examples of non-pulse sounds include those produced by vessels, aircraft, machinery operations such as drilling or dredging, vibratory pile driving, and active sonar systems. The duration of such sounds, as received at a distance, can be greatly extended in a highly reverberant environment. Many of the sounds produced by the project would be transient in nature (i.e., the source moves), such as during vessel docking. Regasification sounds are continuous (while the SRV is docked) and stationary. The positioning (maneuvering and docking) of SRVs VerDate Mar<15>2010 18:22 Sep 07, 2012 Jkt 226001 using thrusters is intermittent (i.e., every 8 days) and of short duration (i.e., 10 to 30 minutes). For this project, the only pulsive sounds are associated with pile driving activities at the offshore Port location (i.e., associated with anchor installation activities). Impact hammers (proposed for use in driving buoy anchors) operate by repeatedly dropping a heavy piston onto a pile to drive the pile into the substrate. Sound generated by impact hammers is characterized by rapid rise times and high peak levels, a potentially injurious combination (Hastings and Popper, 2005). Vibratory hammers, which would be used to install sheet pile and possibly pilings for goal posts inshore, install piles by vibrating them and allowing the weight of the hammer to push them into the sediment. Vibratory hammers produce significantly less sound than impact hammers. Peak SPLs may be 180 dB or greater but are generally 10 to 20 dB lower than SPLs generated during impact pile driving of the same-sized pile (Caltrans, 2009). Rise time is slower, reducing the probability and severity of injury (USFWS, 2009), and sound energy is distributed over a greater amount of time (Nedwell and Edwards, 2002; Carlson et al., 2001). Sound Attenuation Devices Sound levels can be greatly reduced during impact pile driving using sound attenuation devices. There are several types of sound attenuation devices including bubble curtains, cofferdams, and isolation casings (also called temporary sound attenuation piles [TNAP]), and cushion blocks. Port Dolphin considers the installation of cofferdams to be infeasible for this project. The information available suggests that bubble curtains, cushion blocks and caps, and TNAP design offer PO 00000 Frm 00010 Fmt 4701 Sfmt 4702 comparable levels of sound attenuation for pile driving. Port Dolphin proposes to implement one or more of these techniques during the pile driving activities needed to install components of the STL buoys and will make a final decision with regard to the technology to be used prior to beginning work. Bubble curtains create a column of air bubbles rising around a pile from the substrate to the water surface. The air bubbles absorb and scatter sound waves emanating from the pile, thereby reducing the sound energy. Bubble curtains may be confined or unconfined. An unconfined bubble curtain may consist of a ring seated on the substrate and emitting air bubbles from the bottom. A confined bubble curtain contains the air bubbles within a flexible or rigid sleeve made from plastic, cloth, or pipe. Confined bubble curtains generally offer higher attenuation levels than unconfined curtains because they may physically block sound waves and they prevent air bubbles from migrating away from the pile. For this reason, the confined bubble curtain is commonly used in areas with high current velocity (Caltrans, 2009). An isolation casing is a hollow pipe that surrounds the pile, isolating it from the in-water work area. The casing is dewatered before pile driving. This device provides levels of sound attenuation similar to that of bubble curtains (Caltrans, 2009). Sound levels can be reduced by 8 to 14 dB. Cushion blocks consist of materials (e.g., wood, nylon) placed atop piles during impact pile driving activities to reduce source levels. Typically sound reduction can range from 4 to a maximum of 26 dB. Both environmental conditions and the characteristics of the sound attenuation device may influence the E:\FR\FM\10SEP3.SGM 10SEP3 55655 Federal Register / Vol. 77, No. 175 / Monday, September 10, 2012 / Proposed Rules effectiveness of the device. According to Caltrans (2009): • In general, confined bubble curtains attain better sound attenuation levels in areas of high current than unconfined bubble curtains. If an unconfined device is used, high current velocity may sweep bubbles away from the pile, resulting in reduced levels of sound attenuation. • Softer substrates may allow for a better seal for the device, preventing leakage of air bubbles and escape of sound waves. This increases the effectiveness of the device. Softer substrates also provide additional attenuation of sound traveling through the substrate. • Flat bottom topography provides a better seal, enhancing effectiveness of the sound attenuation device, whereas sloped or undulating terrain reduces or eliminates its effectiveness. • Air bubbles must be close to the pile; otherwise, sound may propagate into the water, reducing the effectiveness of the device. • Harder substrates may transmit ground-borne sound and propagate it into the water column. The literature presents a wide array of observed attenuation results for bubble curtains (see, e.g., WSF, 2009; WSDOT, 2008; USFWS, 2009; Caltrans, 2009). The variability in attenuation levels is due to variation in design, as well as differences in site conditions and difficulty in properly installing and operating in-water attenuation devices. As a general rule, reductions of greater than 10 dB cannot be reliably predicted (Caltrans, 2009). Sound Thresholds Since 1997, NMFS has used generic sound exposure thresholds to determine when an activity in the ocean that produces sound might result in impacts to a marine mammal such that a take by harassment or injury might occur (NMFS, 2005b). To date, no studies have been conducted that examine impacts to marine mammals from which empirical sound thresholds have been established. Current NMFS practice regarding exposure of marine mammals to high level sounds is that cetaceans exposed to impulsive sounds of 180 dB rms or above are considered to have been taken by Level A (i.e., injurious) harassment. Behavioral harassment (Level B) is considered to have occurred when marine mammals are exposed to sounds at or above 160 dB rms for impulse sounds (e.g., impact pile driving) and 120 dB rms for continuous sound (e.g., vessel sound, vibratory pile driving) but below injurious thresholds. Distance to Sound Thresholds This section details sound source modeling produced under contract by the applicant (JASCO, 2008, 2010) and describes the predicted distances to relevant regulatory sound thresholds for the specified activities. NMFS has determined that this information represents the best information available for project sound sources and has used the information to develop mitigation measures and to estimate potential incidental take in this document. The modeling scenarios considered all sound sources associated with the project and were developed to thoroughly characterize the various construction/installation and operation activities expected. The relevant information is summarized in Table 6. The equipment list associated with each activity is based on current construction plans for the Port (Ocean Specialists, 2007). For each piece of equipment specified, proxy vessels were selected from JASCO Research’s database of underwater sound measurements. The sound propagation model used several parameters, including expected water column sound speeds, bathymetry (water depth and shape of the ocean bottom), and bottom geoacoustic properties (which indicate how much sound is reflected off of the ocean bottom), to estimate the radii of sound impacts (JASCO, 2008). Modeling scenario locations are depicted in Figure 1–4 of Port Dolphin’s application. Please see Appendices C and D in Port Dolphin’s application for a detailed description of this sound source modeling. TABLE 6—REPRESENTATIVE SCENARIOS MODELED DURING THE PORT DOLPHIN SOUND SOURCE ANALYSIS AND RADIAL DISTANCE TO THRESHOLDS Activity Source Modeled location Buoy installation ..... Crane vessel, cargo barge, support vessel. Impact hammer ................................... North STL buoy; offshore DWP site ... Impact hammering Pipelaying, offshore Pipelaying, inshore Pipeline burial, offshore. Pipeline burial, inshore. HDD ....................... mstockstill on DSK4VPTVN1PROD with PROPOSALS3 HDD vibratory driving. Barge, two anchor handling tugs, support tug. Barge, two anchor handling tugs, support tug. Plow system, two anchor handling tugs. Plow system, two anchor handling tugs. Floating spud barge, crane mounted drill, welding equipment, air compressor, generator. Floating spud barge, vibrator, welding equipment, air compressor, generator. SRV ..................................................... Docking at buoy, dead slow, two bow thrusters and one stern thruster. Regasification ........ SRV ..................................................... Y-connector; offshore DWP site .......... 15-m isobath ........................................ Tampa Bay .......................................... 15-m isobath ........................................ Tampa Bay .......................................... Tampa Bay .......................................... Distance to threshold 1,2 Approximate area encompassed by threshold 2 180 120 180 160 180 120 180 120 180 120 180 120 180 120 180 120 180 160 180 120 180 120 180 120 180 120 180 120 dB: dB: dB: dB: dB: dB: dB: dB: dB: dB: dB: dB: dB: dB: <0.2 km ... 3.9 km ..... 0.18 km ... 4.5 km ..... <0.2 km ... 7.5 km ..... <0.2 km ... 6.0 km ..... <0.2 km ... 8.4 km ..... <0.2 km ... 6.7 km ..... <0.01 km 0.24 km ... dB: dB: dB: dB: dB: dB: dB: dB: dB: dB: dB: dB: dB: dB: <0.13 km 2 48 km 2 0.10 km 2 64 km 2 <0.13 km 2 177 km 2 <0.13 km 2 113 km 2 <0.13 km 2 222 km 2 <0.13 km 2 141 km 2 <0.00 km 2 0.2 km 2 Tampa Bay .......................................... 180 dB: <0.01 km 120 dB: 12.6 km ... 180 dB: <0.00 km 2 120 dB: 499 km 2 STL buoy; offshore DWP site ............. 180 dB: <0.01 km 120 dB: 3.6 km ..... 180 dB: <0.00 km 2 120 dB: 41 km 2 STL buoy; offshore DWP site ............. 180 dB: 0.00 km ... 120 dB: 0.17 km ... 180 dB: <0.00 km 2 120 dB: 0.09 km 2 Source: JASCO, 2008, 2010. 1 All distances are unweighted, 95th percentile radial distances. 2 For distances not given precisely (e.g., <0.2 km) area of ensonification was modeled using a radial distance of 200 m. Although the distance to threshold would be less than 200 m, it is not possible to specifically calculate the distance because the scenarios involve multiple vessel components. VerDate Mar<15>2010 18:22 Sep 07, 2012 Jkt 226001 PO 00000 Frm 00011 Fmt 4701 Sfmt 4702 E:\FR\FM\10SEP3.SGM 10SEP3 mstockstill on DSK4VPTVN1PROD with PROPOSALS3 55656 Federal Register / Vol. 77, No. 175 / Monday, September 10, 2012 / Proposed Rules Note that in many cases the scenarios involve multiple pieces of equipment. Although equipment spacing would vary during the course of operations, a single layout must be assumed for modeling purposes. As such, where multiple vessels were involved in the scenarios listed in Table 6 the following layout was assumed: • The barge used for the main operation in each scenario (e.g., crane vessel, pipe laying barge, pipe burial barge) was set in the middle of the group of vessels. • For four or fewer tugs (anchor handling and/or support), tugs were spaced at a range of 100 m (328 ft) from the center of the barge. Note that the pipe laying/burial barge itself is 122 m long x 30 m wide (400 x 100 ft). The radii to sound thresholds vary for the same activity depending on water depth, because the transmission of lower-frequency sound waves can be significantly reduced in shallower water. As a result, the radii to the Level A and Level B harassment isopleths in Tampa Bay (i.e., shallower water) are shorter than those that would occur offshore. In addition, much of the energy from the vessels associated with pipelaying occurs at low frequencies and would propagate poorly in shallower water. Although sounds created by construction equipment and vessels would be continuous during pipeline installation, activities would progress slowly along the pipeline route as the pipeline is laid and buried and the trench backfilled. Any one area would be subject to the maximum sound levels for only 1 to 2 days at a time as the construction activities pass that area. Sound modeling indicates that, overall, operational sound associated with the proposed project is consistent with other man-made underwater sound sources in the area (e.g., commercial shipping and dredging). Appendix E of Port Dolphin’s application presents Level B harassment sound field graphics for construction activities. Specific Activity Descriptions—As described previously, the applicant provided detailed sound source modeling for all sound-producing activities associated with the project. In the following sections, each specific type of activity is described in terms of the modeling scenario; the type, duration, and timing of sound produced by the activity; and the radial distances to relevant sound thresholds. All radial distances to thresholds presented in the following sections are modeled, and may be different from the actual distances as determined through site- VerDate Mar<15>2010 18:22 Sep 07, 2012 Jkt 226001 specific acoustic monitoring conducted during the specified activities. Buoy Installation—Proxies were selected for the crane and support vessels based on vessel specifications. While a cargo barge may be present onsite for a portion of the operations, Port Dolphin assumed that this barge would typically not be under power. Installation of the buoys at the Port would produce continuous sound for a relatively short period of time during summer, with the 120-dB isopleth located 3.9 km (2.4 mi) from each STL buoy location. Impact Pile Driving—During the construction period, impact hammering would produce the loudest sound levels but would likely occur only for short periods of time. The source depth for pile driving was set to approximately half the local water depth. In actuality, sound would radiate from all portions of the pilings; this midwater column value is a precautionary estimate of the depth for an equivalent point source, as losses due to bottom and surface interactions would be less for a source at mid-depth than for one near the sea floor or surface. Impact hammering operations would involve a pipe lay barge and tugs, similar to pipe laying operations. However, because the potential impact to marine mammals is different for impulsive and continuous sources, impact hammering sound (an impulsive source) is considered separately from vessel sound (non-pulsed sources). Note that the source levels from impact hammering are much higher than those from the vessels that are likely to be onsite. Impact hammering offshore would encompass an area with a radius of approximately 180 m (591 ft) to the Level A threshold; radii to the 160-dB isopleths for this impulsive source would be at 4.5 km (2.8 mi). Pipe Laying—Pipe laying activities would generate continuous, transient, and variable sound levels during construction predominantly during fall, with some activity during late summer and early winter. Two sites were selected for pipe laying: one approximately midway along the offshore portion of the pipeline and another along the inshore portion. Equipment lists for the offshore and inshore sites are identical: a pipe laying barge, two tugs involved in re-setting of anchors, and a third tug in transit. Sound impacts from pipelaying would produce a 6.0 or 7.5 km (3.7–4.7 mi) radius to the 120-dB isopleth inshore and offshore, respectively. Pipe Burial—Pipeline burial using the plow system would generate continuous, transient, and variable sound levels during construction, PO 00000 Frm 00012 Fmt 4701 Sfmt 4702 primarily during fall and winter. Pipeline burial would be used infrequently during the construction period. Similarly to pipe laying, pipe burial using a trenching plow system would consist of an anchored barge accompanied by two anchor handling tugs. In addition, sound would be generated by the plow used to bury the pipeline. Detailed source level data were not available for plow operations. However, Aspen Environmental Group (2005) reported a broadband source level of 185 dB. Based on this information, similar source levels from dredge operations (Greene, 1987) were used for the applicant’s modeling purposes. Note that the dredge source levels include the sound from the barge upon which the dredge is operated; consequently, a separate barge is not specified for plowing operations in Table 6. The modeling scenario used the depth of the barge hull under the water as the sound source depth, rather than the depth of the actual dredge work. This is because observations from clamshell dredging show that the highest levels of underwater sound are emitted from equipment on the barge (propagating through the hull) rather than from the scraping sounds of the dredge itself (Richardson et al., 1995). Pipeline burial using the plow system produces sound attenuating to the 120dB isopleth at 6.7 km (4.2 mi) inshore and 8.4 km (5.2 mi) offshore. HDD—HDD within Tampa Bay would produce continuous sound levels and is expected to occur during summer. Installation of the goal posts (described previously under ‘‘Pipeline Installation’’) at each HDD location would produce a continuous sound for a relatively short period of time and would only occur during summer. HDD would be employed for installation of the pipeline at a number of locations along the inshore portion of the route, including the Port Manatee shore approach and two crossings of the existing Gulfstream pipeline. Drilling and vibratory driving (for goal posts/ sheet pile) would be conducted from a floating spud barge approximately 41 m in length. Drilling would involve a crane-mounted drill, suspended from a crawler crane on the barge. The barge would also be equipped with welding equipment, an air compressor, and a generator. Source levels for drilling of the pilot holes are based on measurements made by Greene (1987) during drilling operations in the Beaufort Sea. As with drilling from a barge, these measurements include contributions from both the drill assembly itself and from equipment on the drill platform E:\FR\FM\10SEP3.SGM 10SEP3 mstockstill on DSK4VPTVN1PROD with PROPOSALS3 Federal Register / Vol. 77, No. 175 / Monday, September 10, 2012 / Proposed Rules (e.g., generators). Because the dominant sound source is equipment located on the drilling vessel (Richardson et al., 1995) rather than the drilling or scraping itself, a source level height of 2.2 m was used, as it was for other barge-mounted activities modeled by JASCO. Source levels for the vibratory driver were derived from measurements made by JASCO. The vibratory driver was mounted on a moored barge during the measurements, and so sound contributions from equipment on the barge are included in the source level estimates. The measured driver is larger than the vibratory driver planned for use at Port Dolphin. However, very few measurements of underwater sound exist for pile drivers of this size, and in most cases the available reports do not describe the vibratory driver used. Additionally, scaling by vibratory driver specifications (e.g., the eccentric moment) is made difficult by the fact that pile driving source levels depend not only on the equipment but also on the piling, substrate and environment. As such, JASCO’s un-scaled measurements of underwater sound are used here as a conservative estimate of the sound likely to be generated during installation of the goal posts/sheet pile. As for the impact pile driving described previously, the source depth for pile driving was conservatively set to half the local water depth, i.e., 3.5 m. Modeling results (JASCO, 2010) indicate that the 120-dB isopleth would extend 240 m (787 ft) from the drilling operation, while the 120-dB isopleth for HDD vibratory driving would extend 12.6 km (7.8 mi) from the source. SRV Docking—Once the SRV completes its approach to Port Dolphin and is within approximately 5.6 km (3.5 mi) of the Port, bow and stern thrusters would be utilized. Thruster use would vary, operating for 10 to 30 minutes to allow for the proper positioning of the vessel and for connection to the STL buoy. Docking or berthing would occur at alternate STL buoys approximately every 8 days. Sound modeling, assessing the periodic use of the thrusters (i.e., every 8 days) producing an intermittent and moving sound, indicated that the 120-dB isopleth would occur at 3.6 km (2.2 mi) from the SRV. Operational procedures for the SRVs specify probable use of thrusters during approach and docking. Speed is gradually reduced as the SRV approaches the unloading buoys, until main propulsion is at dead slow. Bow and stern thrusters are used during docking. Once moored, ship’s propulsion is not required for positioning. Based on these operational VerDate Mar<15>2010 19:05 Sep 07, 2012 Jkt 226001 procedures, the sample situation described in Table 6 was selected for modeling; i.e., docking at the northern buoy, using both bow thrusters and one stern thruster. Very little information is available on the underwater sound levels produced by LNG carriers. However, some data and empirical formulas have been developed for large tankers in general. At typical cruising speeds, source levels from such vessels are dominated by propeller cavitation (Sponagle, 1988; Seol et al., 2002). As described by LGL and JASCO (2005), an empirical expression for the source spectrum level (1 Hz bandwidth) in the frequency range between 100 Hz and 10 kHz is SL = 163 + 10 log BD4N3 f¥2 where B is the number of blades, D is the propeller diameter in meters, N is the number of propeller revolutions per second, and f is the frequency in Hz. For frequencies less than 100 Hz, the source level is assumed to be constant at the 100 Hz level. In the case of ducted propellers (e.g., bow and stern thrusters), the constant is approximately 7 dB larger. Specifications for the main propulsion system are based on a typical carrier, and are similar to those described by LGL and JASCO (2005). Bow and stern thrusters are expected to be single-speed, controllable-pitch devices, with power ratings of 2,000 kW each for the bow thrusters and 1,200 kW each for the stern thrusters. Based on these values, diameters and rates of revolution for the thrusters were based on specifications for the most common models currently available. The above model is not able to take into account the reduction in source levels that would result from a change in pitch at lower power outputs; hence, the modeled source levels are conservative (i.e., represent maximum expected levels of underwater sound). Regasification—The SRV would regasify its LNG cargo while moored at the STL buoy. Sound levels for regasification are low, and the modeling predicts that the 120-dB isopleths would be only 170 m (558 ft) from the source. The following additional sources of underwater sound are expected to be present during construction of the DWP, but were not modeled: • Dredging: Dredging would be involved in a few stages of construction, including HDD (discussed later) and pipelaying at the Sunshine Bridge crossing (Ocean Specialists, 2007). This would involve a clamshell or bucketstyle dredge, operated from a barge while one or more additional barges carry out other tasks nearby. PO 00000 Frm 00013 Fmt 4701 Sfmt 4702 55657 Measurements taken by JASCO during operation of a clamshell dredge indicated source levels of approximately 150–155 dB, i.e., roughly 20 dB lower than the source levels associated with the barge used during pipe laying operations. As such, dredging may be considered an insignificant source of sound compared with operation of the barges that would also be present. • Transponders: Once the port is operational, an additional source of underwater sound in the vicinity of the unloading buoys would be the acoustic transponders installed on the buoys. Information was not available on the specific transponders intended for use at the DWP; however, specifications from commercially available buoy positioning transponders indicate operating frequencies of a few tens of kHz, and source levels of approximately 190 dB. Given this estimated broadband source level, we may estimate ranges to various threshold values assuming simple spherical spreading, i.e., RL = SL ¥ 20log10(r). Solving for r shows that received levels would drop to 180 dB at a range of approximately 3 m, and to 160 dB at a range of approximately 32 m; further, this sound source would be highly intermittent, as the transponders would only transmit, briefly, when interrogated by the SRV-based command unit. As such, only marine mammals passing very near the unloading buoys during the brief period of transmittance would potentially be affected, and effects from these sources may be considered discountable. Comments and Responses On March 1, 2011, NMFS published a notice of receipt of an application for a Letter of Authorization (LOA) in the Federal Register (76 FR 11205) and requested comments and information from the public for 30 days. NMFS did not receive any substantive comments. Description of Marine Mammals in the Area of the Specified Activity Twenty-nine marine mammals (28 cetaceans and the Florida manatee [Trichechus manatus]) have documented occurrences in the GOM (Wursig et al., 2000). The manatee is under the jurisdiction of the U.S. Fish and Wildlife Service, and will not be discussed further in this document. Of the cetaceans, seven are mysticetes (baleen whales) and 21 are odontocetes (toothed whales, including dolphins). Table 7 contains a summary of relevant information for each of these 28 species. E:\FR\FM\10SEP3.SGM 10SEP3 55658 Federal Register / Vol. 77, No. 175 / Monday, September 10, 2012 / Proposed Rules TABLE 7—MARINE MAMMALS IN THE GULF OF MEXICO Typical habitat Status a Species Occurrence b Coastal Shelf Slope/Deep Order Cetacea Suborder Mysticeti Family Balaenidae: North Atlantic right whale (Eubalaena glacialis) ..................... Family Balaenopteridae. Blue whale (Balaenoptera musculus) ..................................... Bryde’s whale (Balaenoptera edeni) ...................................... Fin whale (Balaenoptera physalus) ........................................ Humpback whale (Megaptera novaeangliae) ......................... Minke whale (Balaenoptera acutorostrata) .................................... Sei whale (Balaenoptera borealis) ................................................. E 1 ...................... X X E ...................... E E ...................... E 1 3 2 2 2 2 ...................... ...................... ...................... ...................... ...................... ...................... X X X X X X X X X X X X ...................... ...................... E 3 3 4 ...................... ...................... ...................... X X X X X X ...................... ...................... ...................... ...................... 2c 2c 3c 1c ...................... ...................... ...................... ...................... X X X X X X X X ...................... ...................... ...................... ...................... ...................... ...................... ...................... ...................... ...................... ...................... ...................... ...................... ...................... ...................... 4 4 4 3 4 3 4 4 3 4 4 4 4 4 X X ...................... ...................... ...................... ...................... ...................... ...................... ...................... ...................... ...................... ...................... ...................... ...................... X X X X X ...................... ...................... X X X X X X X X X X X X X X X X X X X X X Suborder Odontoceti Family Physeteridae: Dwarf sperm whale (Kogia sima) ........................................... Pygmy sperm whale (Kogia breviceps) .................................. Sperm whale (Physeter macrocephalus) ............................... Family Ziphiidae: Blainville’s beaked whale (Mesoplodon densirostris) ............. Cuvier’s beaked whale (Ziphius cavirostris) ........................... Gervais’ beaked whale (Mesoplodon europaeus) .................. Sowerby’s beaked whale (Mesoplodon bidens) ..................... Family Delphinidae: Atlantic spotted dolphin (Stenella frontalis) ............................ Bottlenose dolphin (Tursiops truncatus) ................................. Clymene dolphin (Stenella clymene) ...................................... False killer whale (Pseudorca crassidens) ............................. Fraser’s dolphin (Lagenodelphis hosei) ................................. Killer whale (Orcinus orca) ..................................................... Melon-headed whale (Peponocephala electra) ...................... Pantropical spotted dolphin (Stenella attenuata) ................... Pygmy killer whale (Feresa attenuata) ................................... Short-finned pilot whale (Globicephala macrorhynchus) ........ Risso’s dolphin (Grampus griseus) ........................................ Rough-toothed dolphin (Steno bredanensis) .......................... Spinner dolphin (Stenella longirostris) .................................... Striped dolphin (Stenella coeruleoalba) ................................. mstockstill on DSK4VPTVN1PROD with PROPOSALS3 ¨ Source: Wursig et al., 2000 a Status: E = Listed as endangered under the Endangered Species Act. b Occurrence: 1 = extralimital; 2 = rare; 3 = uncommon; 4 = common. c Beaked whales in the GOM may be somewhat more common than survey data indicate, as beaked whales are difficult to sight and identify to species. Most surveys have been conducted in sea states that are not optimal for sighting beaked whales. Of these 28 cetacean species, based on available survey data, only the bottlenose dolphin and Atlantic spotted dolphin are likely to occur regularly in the vicinity of the project area (i.e., coastal and shelf waters of the eastern GOM) (Fulling et al., 2003). Because a small portion of the sound produced by the activity is predicted to extend into the mid-shelf depth stratum, three other species of cetacean—pygmy and dwarf sperm whales and the rough-toothed dolphin—could be affected. Other species of dolphins and an occasional whale are sometimes observed in nearshore GOM waters and might infrequently strand, but these are not considered normal occurrences for those deepwater species that occur more VerDate Mar<15>2010 18:22 Sep 07, 2012 Jkt 226001 regularly in waters around and seaward of the continental shelf break (Mullin and Fulling, 2003a; Mullin et al., 2004). As a result, the potential effects of the specified activity are analyzed only for these five species. As the species to be most affected by the specified activity, bottlenose and spotted dolphin occurrences relative to the project area are discussed in more detail in the following paragraphs. The cetacean fauna of the northern and eastern GOM continental shelf, including the project area, typically consists of the bottlenose dolphin and the Atlantic spotted dolphin (Davis and Fargion, 1996; Jefferson and Schiro, 1997; Davis et al., 1998; Davis et al., ¨ 2000; Wursig et al., 2000). At the shelf PO 00000 Frm 00014 Fmt 4701 Sfmt 4702 edge and within the deeper waters of the continental slope, the cetacean community typically includes nineteen species, including the Bryde’s whale, sperm whale, pygmy and dwarf sperm whales, three species of beaked whales, and twelve species of oceanic dolphins. Oceanographic and bathymetric features (e.g., eddies, water temperature, salinity) are important factors in determining the distribution of marine mammals, in large part because the presence of prey is frequently influenced by such features (Katona and Whitehead, 1988; Biggs et al., 2000; Wormuth et al., 2000; Davis et al., 2002). The presence of specific hydrographic and/or bathymetric features and discontinuities (e.g., abrupt E:\FR\FM\10SEP3.SGM 10SEP3 mstockstill on DSK4VPTVN1PROD with PROPOSALS3 Federal Register / Vol. 77, No. 175 / Monday, September 10, 2012 / Proposed Rules temperature differentials, current edges, upwelling areas, sea mounts, banks, shoals, the continental shelf edge) may also affect marine mammal distribution (USDON, 2003). The following discussions of the population status of GOM marine mammals use categories adapted from ¨ Wursig et al. (2000): • Common: A species that is abundant and widespread throughout the region in which it occurs; • Uncommon: A species that does not occur in large numbers and may or may not be widely distributed throughout the region in which it occurs; • Rare: A species present in such small numbers throughout the region that it is seldom seen; and • Extralimital: A species known on the basis of few records that are probably the result of unusual movements of few individuals into the region. Data historically acquired during aerial and shipboard surveys conducted within the eastern GOM were analyzed by marine mammal researchers and summarized in USDON (2003). To increase the utility of the species sightings data, marine mammal occurrence and distribution data were partitioned into both seasonal and water depth categories. This partitioning is supported by distribution patterns (e.g., sightings over the continental shelf, sightings beyond the continental shelf) observed during large-scale surveys (e.g., Cetacean and Turtle Assessment Program [CETAP] surveys; CETAP, 1982; Hain et al., 1985; Winn et al., 1987). Seasonal categories included in USDON (2003) and employed in this analysis were: • Winter: December 21 through March 20; • Spring: March 21 through June 20; • Summer: June 21 through September 20; and • Fall: September 21 through December 20. Water depth categories, or depth strata, included in USDON (2003) and employed in this analysis were as follows: • Nearshore: 0 to 120 ft (0 to 36.6 m); • Mid-shelf: 120 to 300 ft (36.6 to 91.4 m); • Shelf-edge: 300 to 6,600 ft (91.4 to 2,000 m); and • Slope: > 6,600 ft (> 2,000 m). The U.S. Department of the Navy (USDON, 2003) reviewed available marine mammal survey data for the eastern GOM and summarized species presence and distribution on a seasonal basis. Relevant findings pertinent to marine mammals include the following: • Spring is the season with the highest number of cetacean occurrence VerDate Mar<15>2010 18:22 Sep 07, 2012 Jkt 226001 records, although high numbers of cetacean occurrence records were also noted for summer; • Fall and winter are the two seasons with the lowest number of occurrence records and total number of cetaceans; • Higher numbers in spring and summer are possibly due to the higher survey effort usually expended during those months (when sighting conditions are optimal); and • There are fewer sighting records in fall than in the other seasons, likely attributable to suboptimal survey conditions (i.e., reduction in sightability). Mysticetes The Bryde’s whale is the most frequently sighted mysticete in the Gulf, though considered uncommon. Strandings and sightings data suggest that this species may be present throughout the year, generally in the northeastern Gulf near the 100-m (328ft) isobath between the Mississippi River delta and southern Florida (Davis ¨ et al., 2000; Wursig et al., 2000). The remaining six mysticete whales (blue, fin, humpback, minke, sei, and North Atlantic right whales) are considered rare or extralimital in the GOM (Jefferson, 1996; Jefferson and Schiro, 1997). Mysticete whales, including the Bryde’s whale, could occur within the project area although such occurrence would be extremely unlikely. Odontocetes Bottlenose dolphins and spotted dolphins are known to occur regularly in the project area and are the species to be most affected by the project. In addition, there is some possibility that pygmy and dwarf sperm whales and rough-toothed dolphins could occur in deeper waters ensonified by some offshore project activities. Most of the odontocetes known to occur within the Gulf (Table 7) are considered common. Exceptions include the beaked whales, with most being rare or extralimital, and the dwarf and pygmy sperm whales, which are considered uncommon. The frequency of occurrence of beaked whales and dwarf and pygmy sperm whales are most likely underestimated because these cryptic species are submerged much of the time and avoid ¨ aircraft and ships (Wursig et al., 1998). Consequently, these species may be somewhat more common than is indicated by survey data but are still likely to be relatively uncommon. The sperm whale is considered common in the Gulf (Jefferson, 1996; Jefferson and Schiro, 1997; Davis et al., 2000; Waring et al., 2006). Sightings data suggest a Gulf-wide distribution on the PO 00000 Frm 00015 Fmt 4701 Sfmt 4702 55659 continental slope. Congregations of sperm whales are common along the continental shelf edge in the vicinity of the Mississippi River delta in water depths of 500 to 2,000 m (1,640–6,562 ft). As a result of these consistent sightings, it is believed that there is a resident population of sperm whales in the Gulf consisting of adult females, calves, and immature individuals (Brandon and Fargion, 1993; Mullin et al., 1994; Sparks et al., 1993; Jefferson and Schiro, 1997). Though most odontocetes (including delphinids) are considered common in the GOM, they prefer waters of the continental shelf edge (approximately 200 m [656 ft]) or deeper waters of the continental slope. Therefore, it is unlikely that these species would occur within the project area (i.e., Tampa Bay and nearshore waters). Due to the rarity of the majority of odontocete species, as well as the mysticetes discussed previously, in the proposed project area and the remote chance they would be affected by Port Dolphin’s proposed port operations, these species are not considered further in this analysis. The most commonly sighted cetaceans on the GOM continental shelf (in terms of numbers of individual sightings) during systematic surveys conducted in the mid to late 1990s (i.e., GulfCet II) were bottlenose dolphins and Atlantic spotted dolphins. Brief discussions of these commonly sighted marine mammal species are provided in the following subsections. Bottlenose dolphins—The bottlenose dolphin is a common inhabitant of both the continental shelf and slope in the GOM, generally in waters less than 20 m (66 ft) (Griffin and Griffin, 2003). The species is also distributed throughout the bays, sounds, and estuaries of the GOM (Mullin et al., 1990). Bottlenose dolphins are opportunistic feeders, taking a wide variety of fish, cephalopods, and shrimp (Wells and Scott, 1999) and using a wide variety of feeding strategies (Shane, 1990). In the GOM, bottlenose dolphins often feed in association with shrimp trawlers (Fertl and Leatherwood, 1997). In addition to the use of active echolocation to find food, bottlenose dolphins likely detect and orient to fish prey by listening for the sounds prey produce—so-called ‘passive listening’ (Barros and Myrberg, 1987; Gannon et al., 2005). Nearshore bottlenose dolphins prey predominately on coastal fish and cephalopods, while offshore individuals prey on pelagic cephalopods and a large variety of epiand mesopelagic fish species (Van Waerebeek et al., 1990; Mead and Potter, 1995). E:\FR\FM\10SEP3.SGM 10SEP3 mstockstill on DSK4VPTVN1PROD with PROPOSALS3 55660 Federal Register / Vol. 77, No. 175 / Monday, September 10, 2012 / Proposed Rules NMFS recognizes several stocks of bottlenose dolphins in the GOM, including a northern oceanic stock; a continental shelf and slope stock; western, northern, and eastern coastal stocks; and a group of 32 bay, sound, and estuarine stocks (Blaylock et al., 1995; Waring et al., 2006). Bottlenose dolphins likely occur within both offshore and nearshore waters of the project area. Bottlenose dolphins present in the project area would likely be represented by individuals from the eastern coastal stock and the relevant bay, sound, and estuarine stocks. Bottlenose dolphins along the U.S. coastline are believed to be organized into local populations, or stocks, each occupying a small region of coast with some migration to and from inshore and offshore waters (Schmidly, 1981). The seaward boundary for coastal stocks, the 20-m (66-ft) isobath, generally corresponds to survey strata (Scott, 1990; Blaylock and Hoggard, 1994; Fulling et al., 2003) and represents a management boundary rather than an ecological boundary. Both ‘‘coastal/ nearshore’’ and ‘‘offshore’’ ecotypes of bottlenose dolphins (Hersh and Duffield, 1990) occur in the GOM (LeDuc and Curry, 1998), and both could potentially occur in coastal waters. The best abundance estimate available for the northern GOM eastern coastal stock of bottlenose dolphins is 7,702, with a minimum population estimate of 6,551. The status of the eastern coastal stock relative to optimum sustainable population (OSP) level is not known and population trends cannot be determined due to insufficient data. The eastern coastal stock is not considered a strategic stock under the MMPA because the stock’s average annual human-related mortality and serious injury does not exceed potential biological removal (PBR) (Waring et al., 2010). Bottlenose dolphins are distributed throughout the bays, sounds and estuaries of the GOM (Mullin, 1988). The identification of biologicallymeaningful ‘‘stocks’’ of bottlenose dolphins in these waters is complicated by the high degree of behavioral variability exhibited by this species (Shane et al., 1986; Wells and Scott, 1999; Wells, 2003), and by the lack of requisite information for much of the region. However, distinct stocks are provisionally identified in each of 32 areas of contiguous, enclosed or semienclosed bodies of water adjacent to the northern GOM. Bay, sound, and estuarine dolphins found in the project area would likely be from Tampa Bay or Sarasota Bay. VerDate Mar<15>2010 18:22 Sep 07, 2012 Jkt 226001 These ‘‘communities’’ include resident dolphins that regularly share large portions of their ranges, exhibit similar distinct genetic profiles, and interact with each other to a much greater extent than with dolphins in adjacent waters. While these communities do not constitute closed demographic populations, the geographic nature of these areas and long-term, multi-generational stability of residency patterns suggest that they may exist as discrete, functioning units of their ecosystems. Members of these stocks emphasize use of the bay, sound, or estuary waters, with limited movements through passes to the GOM (Shane, 1977, 1990; Gruber, 1981; Irvine ¨ et al., 1981; Maze and Wursig, 1999; ¨ Lynn and Wursig, 2002; Fazioli et al., 2006). These habitat use patterns are reflected in the ecology of the dolphins in some areas; for example, residents of Sarasota Bay, Florida, lack squid in their diet, unlike non-resident dolphins found stranded on nearby Gulf beaches (Barros and Wells, 1998). Genetic exchange occurs between resident communities; hence the application of the demographically and behaviorally-based term ‘‘community’’ rather than ‘‘population’’ (Wells, 1986a; Sellas et al., 2005). A variety of potential exchange mechanisms occur in the Gulf. Small numbers of inshore dolphins traveling between regions have been reported, with patterns ranging from traveling through adjacent communities (Wells, 1986b; Wells et al., 1996a,b) to movements over distances of several hundred kilometers in Texas waters ¨ (Gruber, 1981; Lynn and Wursig, 2002). In many areas, year-round residents cooccur with non-resident dolphins, providing potential opportunities for genetic exchange. Non-residents exhibit a variety of patterns, ranging from apparent nomadism recorded as transience to apparent seasonal or nonseasonal migrations. Passes, especially the mouths of the larger estuaries, serve as mixing areas. For example, several communities mix at the mouth of Tampa Bay (Wells, 1986a). Seasonal movements of dolphins into and out of some of the bays, sounds and estuaries provide additional opportunities for genetic exchange with residents, and complicate the identification of stocks in coastal and inshore waters. In larger bay systems (e.g., Tampa Bay), seasonal changes in abundance suggest possible migrations, and fall/ winter increases in abundance have been noted for Tampa Bay (Scott et al., 1989). A number of geographically and socially distinct subgroupings of dolphins in some regions, including Tampa Bay, have been identified, but PO 00000 Frm 00016 Fmt 4701 Sfmt 4702 the importance of these distinctions to stock designations remains undetermined. For Tampa Bay, Urian et al. (2009) recently described fine-scale population structuring into five discrete communities (including the adjacent Sarasota Bay community) that differed in their social interactions and ranging patterns. Structure was found despite a lack of physiographic barriers to movement within this large, open embayment. In the vicinity of the action area, there are distinct geographic subdivisions with year-round resident animals from Tampa Bay, Sarasota Bay, and Charlotte Harbor as well as a seasonal coastal stock (discussed previously; 1 to 12 km [0.6–7.5 mi] offshore) with mixing on a limited basis (Wells et al., 1996; Wells and Scott, 2002; Sellas et al., 2005). The Sarasota community’s range extends from southern Tampa Bay southward through Sarasota Bay, and into the GOM about 1 km offshore. Waring et al. (2010) identified the animals in Tampa Bay as having a best estimate of abundance of 559 individuals (based on 1994 data) and those in Sarasota Bay as having a best abundance estimate of 160 individuals (based on 2007 data). The status of the stock relative to OSP is unknown. Because most of the stock sizes are currently unknown, but likely small, and relatively few mortalities or serious injuries would exceed PBR, NMFS considers that each of these stocks is a strategic stock under the MMPA (Waring et al., 2010). Atlantic spotted dolphins—Atlantic spotted dolphins are widely distributed in warm temperate and tropical waters of the Atlantic Ocean, including the GOM (Waring et al., 2006). In the northern Gulf, these animals occur mainly on the continental shelf (Jefferson and Schiro, 1997). During GulfCet II aerial and shipboard surveys in the northern GOM, Atlantic spotted dolphins were seen at water depths ranging from 22 to 222 m (72–728 ft) (Mullin and Hoggard, 2000). On the shelf, they were second in abundance to bottlenose dolphins. Atlantic spotted dolphins can be expected to occur on the continental shelf during all seasons. However, they may be more common during spring (Jefferson and Schiro, 1997; Mullin and Hoggard, 2000). It is expected that Atlantic spotted dolphins could occur within offshore waters of the project area. Atlantic spotted dolphins in the northern GOM are abundant in continental shelf waters from between 10 and 200 m (33 to 656 ft) to slope waters < 500 m (1,640 ft) (Fulling et al. 2003; Mullin and Fulling, 2003a). Griffin and Griffin (2003) reported that E:\FR\FM\10SEP3.SGM 10SEP3 mstockstill on DSK4VPTVN1PROD with PROPOSALS3 Federal Register / Vol. 77, No. 175 / Monday, September 10, 2012 / Proposed Rules on the west Florida Shelf they are more common in waters from 20 to 180 m (66 to 591 ft), while Mullin et al. (2004) found that Atlantic spotted dolphins were sighted in waters with a bottom depth typically < 300 m (984 ft). Griffin and Griffin (2004) reported higher abundances of spotted dolphins on the west Florida Shelf between the months of November and May than during the rest of the year. Atlantic spotted dolphins in the GOM have been seen feeding cooperatively on clupeid fishes (e.g., herring, sardine) and are known to feed in association ¨ with shrimp trawlers (Fertl and Wursig, 1995; Fertl and Leatherwood, 1997, respectively). In the Bahamas, this species has been observed to chase and catch flying fish (MacLeod et al., 2004). The only information on dive depth for this species is based on a satellite-tagged individual from the GOM (Davis et al., 1996). This individual made short, shallow dives (more than 76 percent of the time to depths < 10 m) over the continental shelf, although some dives were as deep as 40 to 60 m (Davis et al., 1996). The GOM population is considered a separate stock for management purposes. The most recent abundance estimate for Atlantic spotted dolphin in the GOM, based on pooled survey data from 2000 and 2001, was 37,611 (Waring et al., 2009). These animals were found entirely in OCS waters; the abundance estimate for oceanic waters, from surveys conducted in 2003–04, was zero. There is insufficient information for this stock to determine PBR or its status relative to OSP. Despite an undetermined PBR and unknown population size, the GOM stock is not considered a strategic stock under the MMPA because previous estimates of population size have been large compared to the number of cases of documented human-related mortality and serious injury. In addition to bottlenose and spotted dolphins, three other species that frequent the mid-shelf stratum could be exposed to sound from certain project activities and the potential for incidental harassment of these species has been evaluated (see ESTIMATED INCIDENTAL HARASSMENT). Dwarf and pygmy sperm whales and roughtoothed dolphins may be expected to occur in the mid-shelf stratum on a seasonal basis. The area of actual construction and operations for Port Dolphin is entirely contained within the nearshore depth stratum (0 to 37 m; depth strata were listed earlier). Maximum depth at the DWP is approximately 31 m, while the pipeline route transits increasingly shallower VerDate Mar<15>2010 18:22 Sep 07, 2012 Jkt 226001 waters until entering Tampa Bay and subsequently making landfall. However, while the actual construction activities will be entirely contained within the nearshore stratum, the sound field produced by certain construction activity, and thus the area of effect, extends into the mid-shelf depth stratum (37 to 91 m). Most sound would be contained within the nearshore stratum. The one exception is for the offshore pipelaying activity, which would occur only from late summer 2013 through early winter 2013–14. The Level B sound field for this activity would be 99.9 percent contained within the nearshore stratum, with 0.1 percent potentially entering the mid-shelf stratum. Background on Marine Mammal Hearing Different kinds of marine life are sensitive to different frequencies of sound. Based on available behavioral data, audiograms derived using auditory evoked potential techniques, anatomical modeling, and other data, Southall et al. (2007) designated functional hearing groups for marine mammals and estimated the lower and upper frequencies of functional hearing of the groups. The functional groups and the associated frequencies are indicated below (though animals are less sensitive to sounds at the outer edge of their functional range and most sensitive to sounds of frequencies within a smaller range somewhere in the middle of their functional hearing range): • Low-frequency cetaceans (mysticetes): Functional hearing is estimated to occur between approximately 7 Hz and 22 kHz; • Mid-frequency cetaceans (dolphins, larger toothed whales, beaked and bottlenose whales): Functional hearing is estimated to occur between approximately 150 Hz and 160 kHz; • High-frequency cetaceans (true porpoises, river dolphins, Kogia sp.): Functional hearing is estimated to occur between approximately 200 Hz and 180 kHz; and • Pinnipeds in water: Functional hearing is estimated to occur between approximately 75 Hz and 75 kHz, with the greatest sensitivity between approximately 700 Hz and 20 kHz. As mentioned previously in this document, two species of cetacean, bottlenose and Atlantic spotted dolphins, are likely to occur in the project area. These two species are both classified as mid-frequency cetaceans (Southall et al., 2007). PO 00000 Frm 00017 Fmt 4701 Sfmt 4702 55661 Potential Effects of the Specified Activity on Marine Mammals Potential effects of Port Dolphin’s proposed port construction and subsequent operations are likely to be acoustic in nature. In-water construction activities (e.g., pile driving, pipeline installation) and LNG port operations introduce sound into the marine environment and have the potential to have adverse impacts on marine mammals. The potential effects of sound from the proposed activities associated with the Port might include one or more of the following: Tolerance, masking of natural sounds, behavioral disturbance, non-auditory physical effects, and temporary or permanent hearing impairment (Richardson et al., 1995). However, for reasons discussed later in this document, Port Dolphin’s activities would not likely cause any cases of nonauditory physical effects or temporary or permanent hearing impairment. As outlined in previous NMFS documents, the effects of sound on marine mammals are highly variable and can be categorized as follows (based on Richardson et al., 1995): • The sound may be too weak to be heard at the location of the animal (i.e., lower than the prevailing ambient sound level, the hearing threshold of the animal at relevant frequencies, or both); • The sound may be audible but not strong enough to elicit any overt behavioral response; • The sound may elicit reactions of varying degrees and variable relevance to the well-being of the marine mammal. Reactions can range from temporary alert responses to active avoidance reactions such as vacating an area until the stimulus ceases, but potentially for longer periods of time; • Upon repeated exposure, a marine mammal may exhibit diminishing responsiveness (habituation), or disturbance effects may persist; the latter is most likely with sounds that are highly variable in characteristics and unpredictable in occurrence, and associated with situations that a marine mammal perceives as a threat; • Any anthropogenic sound that is strong enough to be heard has the potential to result in masking, or reduce the ability of a marine mammal to hear biological sounds at similar frequencies, including calls from conspecifics and underwater environmental sounds such as surf sound; • If mammals remain in an area for feeding, breeding, or some other biologically important purpose even though there is chronic exposure to sound, the possibility exists for soundinduced physiological stress; this might E:\FR\FM\10SEP3.SGM 10SEP3 55662 Federal Register / Vol. 77, No. 175 / Monday, September 10, 2012 / Proposed Rules in turn have negative effects on the well-being or reproduction of the animals involved; and • Very strong sounds have the potential to cause a temporary or permanent reduction in hearing sensitivity, also referred to as threshold shift. In terrestrial mammals, and presumably marine mammals, received sound levels must far exceed the animal’s hearing threshold for there to be any temporary threshold shift (TTS). For transient sounds, the sound level necessary to cause TTS is inversely related to the duration of the sound. Received sound levels must be even higher for there to be risk of permanent hearing impairment (PTS). In addition, intense acoustic or explosive events may cause trauma to tissues associated with organs vital for hearing, sound production, respiration, and other functions. This trauma may include minor to severe hemorrhage. mstockstill on DSK4VPTVN1PROD with PROPOSALS3 Tolerance Numerous studies have shown that underwater sounds from industrial activities are often readily detectable by marine mammals in the water at distances of many kilometers. However, other studies have shown that marine mammals at distances more than a few kilometers away often show no apparent response to industrial activities of various types (Miller et al. 2005). This is often true even in cases when the sounds must be readily audible to the animals based on measured received levels and the hearing sensitivity of that mammal group. Although various baleen whales, toothed whales, and (less frequently) pinnipeds have been shown to react behaviorally to underwater sound from sources such as airgun pulses or vessels under some conditions, at other times, mammals of all three types have shown no overt reactions (e.g., Malme et al., 1986; Richardson et al., 1995; Madsen and Mohl, 2000; Croll et al., 2001; Jacobs and Terhune, 2002; Madsen et al., 2002; Miller et al., 2005). In general, small odontocetes seem to be more tolerant of exposure to some types of underwater sound than are baleen whales. Masking Masking is the obscuring of sounds of interest to an animal by other sounds, typically at similar frequencies. Marine mammals are highly dependent on sound, and their ability to recognize sound signals amid other sound is important in communication and detection of both predators and prey. Background ambient sound may interfere with or mask the ability of an animal to detect a sound signal even VerDate Mar<15>2010 18:22 Sep 07, 2012 Jkt 226001 when that signal is above its absolute hearing threshold. Even in the absence of anthropogenic sound, the marine environment is often loud. Natural ambient sound includes contributions from wind, waves, precipitation, other animals, and thermal sound, at frequencies above 30 kHz, resulting from molecular agitation (Richardson et al., 1995). In general, masking effects are expected to be less severe when sounds are transient than when they are continuous. The majority of sound produced during the construction of Port Dolphin would be transient. Masking is typically of greater concern for those marine mammals that utilize low-frequency communications, such as baleen whales and, as such, is not likely to occur for the mid-frequency cetaceans in the project area. Disturbance Behavioral disturbance is one of the primary potential impacts of anthropogenic sound on marine mammals. Disturbance can result in a variety of effects, such as subtle or dramatic changes in behavior or displacement but may be highly dependent upon the context in which the potentially disturbing stimulus occurs. For example, an animal that is feeding may be less prone to disturbance from a given stimulus than one that is not. For many species and situations, there is no detailed information about reactions to sound. While there are no specific studies of the reactions of marine mammals to sounds produced by the construction or operation of a LNG facility, information from studies of marine mammal reactions to other types of continuous and transient anthropogenic sound (e.g., drillships) are described here as a proxy. Behavioral reactions of marine mammals to sound are difficult to predict because they are dependent on numerous factors, including species, maturity, experience, activity, reproductive state, time of day, and weather. If a marine mammal does react to an underwater sound by changing its behavior or moving a small distance, the impacts of that change may not be important to the individual, the stock, or the species as a whole. However, if a sound source displaces marine mammals from an important feeding or breeding area for a prolonged period, impacts on the animals could be important. Based on the literature reviewed in Richardson et al. (1995), most small and medium-sized toothed whales exposed to prolonged or repeated underwater sounds are unlikely to be displaced PO 00000 Frm 00018 Fmt 4701 Sfmt 4702 unless the overall received level is at least 140 dB, although the limited available data indicate that the sperm whale is sometimes, though not always, more responsive to underwater sounds than other toothed whales. Baleen whales, with better hearing sensitivities at lower sound frequencies, have been shown in several studies to react to continuous sounds at received sound levels of approximately 120 dB. Toothed whales appear to exhibit a greater variety of reactions to anthropogenic underwater sound than do baleen whales. Toothed whale reactions can vary from attraction (e.g., bow riding) to strong avoidance, while baleen whale reactions range from neutral (little or no change in behavior) to strong avoidance. Potential disturbance reactions of odontocetes are discussed in somewhat more detail. In their comprehensive literature review, Southall et al. (2007) reported that combined field and laboratory data for mid-frequency cetaceans exposed to non-pulse sounds did not lead to clear conclusions about behavioral responses that may be expected from given received levels of sound. In some settings, individuals in the field showed significant behavioral responses to exposures from 90 to 120 dB, while others failed to exhibit such responses for exposure to received levels from 120 to 150 dB. Species differences, as well as uncontrolled contextual variables other than exposure, are the likely reasons for this variability. Captive subjects were often directly reinforced with food for tolerating exposure to high levels of sound, which likely explains the disparity seen in results from field and laboratory settings—where exposures typically exceeded 170 dB before inducing behavioral responses. Dolphins and other toothed whales may show considerable tolerance of floating and bottom-founded drill rigs and their support vessels, though reactions are variable. Kapel (1979) reported that pilot whales congregated within visual range of drillships and their support vessels off of Greenland. Beluga whales (Delphinapterus leucas) have been observed swimming within 100–150 m (328–492 ft) of an artificial island while drilling was underway and within 1 mi (1.6 km) of a drillship engaged in active drilling (Fraker and Fraker, 1979, 1981). However, other belugas, when exposed to playbacks of drilling sounds, showed avoidance reactions, including altering course, increased swimming speed, and reversed direction of travel (Stewart et al., 1982; Richardson et al., 1995). Reactions of beluga whales to semisubmersible drillship sound were less E:\FR\FM\10SEP3.SGM 10SEP3 mstockstill on DSK4VPTVN1PROD with PROPOSALS3 Federal Register / Vol. 77, No. 175 / Monday, September 10, 2012 / Proposed Rules pronounced than were their reactions to motorboats with outboard engines (Thomas et al., 1990). There may be a significant contextual element to these reactions. Morton and Symonds (2002) used census data on killer whales in British Columbia to evaluate avoidance of nonpulse acoustic harassment devices (AHDs). Avoidance ranges around the AHDs were about 2.5 mi (4 km). Also, there was a dramatic reduction in the number of days resident killer whales were sighted during AHD-active periods compared to pre- and post-exposure periods and a nearby control site. Some species of small toothed whales avoid vessels when they are approached to within 0.5–1.5 km (0.31–0.93 mi), with occasional reports of avoidance at greater distances (Richardson et al., 1995). Some toothed whale species, especially beaked whales and belugas, appear to be more responsive than others. However, dolphins may tolerate vessels of all sizes, often approaching and riding the bow and stern waves (Shane et al., 1986). At other times, dolphin species that are known to be attracted to vessels will avoid them. Such avoidance is often linked to previous vessel-based harassment of the animals (Richardson et al., 1995). Coastal bottlenose dolphins that are the object of dolphin-watching activities have been observed to swim erratically (Acevedo, 1991), remain submerged for longer periods of time (Janik and Thompson, 1996; Nowacek et al., 2001), display less cohesiveness among group members (Cope et al., 1999), whistle more frequently (Scarpaci et al., 2000), and rest less often (Constantine et al., 2004) when vessels were nearby. Pantropical spotted dolphins and spinner dolphins in the Eastern Tropical Pacific, where they have been targeted by commercial fishing vessels because of their association with tuna, display avoidance of survey vessels of up to 11.1 km (6.9 mi; Au and Perryman, 1982; Hewitt, 1985), whereas spinner dolphins in the GOM were observed bow riding the survey vessel in all fourteen sightings during one survey ¨ (Wursig et al., 1998). As evidenced by these observations, the level of response of odontocetes to vessels is thought to be partly a learned behavior, e.g., a function of habituation or a response to some previous negative interaction. Hearing Impairment and Other Physiological Effects Temporary or permanent hearing impairment is a possibility when marine mammals are exposed to very strong sounds. Non-auditory physiological effects might also occur in marine VerDate Mar<15>2010 18:22 Sep 07, 2012 Jkt 226001 mammals exposed to strong underwater sound. Possible types of non-auditory physiological effects or injuries that may occur in mammals close to a strong sound source include stress, neurological effects, bubble formation, and other types of organ or tissue damage. Some marine mammal species (e.g., beaked whales) may be especially susceptible to injury and/or stranding when exposed to strong pulsed sounds, particularly at higher frequencies. Nonauditory physiological effects are not anticipated to occur as a result of the proposed activities, which largely do not include strong pulsed sounds. The following subsections discuss in more detail the possibilities of TTS and PTS. TTS—TTS, reversible hearing loss caused by fatigue of hair cells and supporting structures in the inner ear, is the mildest form of hearing impairment that can occur during exposure to a strong sound (Kryter, 1985). While experiencing TTS, the hearing threshold rises, and a sound must be stronger in order to be heard. TTS can last from minutes or hours to (in cases of strong TTS) days. For sound exposures at or somewhat above the TTS threshold, hearing sensitivity in both terrestrial and marine mammals recovers rapidly after exposure to the sound ends. NMFS considers TTS to be a form of Level B harassment rather than injury, as it consists of fatigue to auditory structures rather than damage to them. The NMFS-established 180-dB injury criterion is considered to be the received level above which, in the view of a panel of bioacoustics specialists convened by NMFS before TTS measurements for marine mammals became available, one could not be certain that there would be no injurious effects, auditory or otherwise, to cetaceans. Few data on sound levels and durations necessary to elicit mild TTS have been obtained for marine mammals, and none of the published data concern TTS elicited by exposure to multiple pulses of sound. Human non-impulsive sound exposure guidelines are based on exposures of equal energy (the same sound exposure level [SEL]; SEL is reported here in dB re: 1 mPa2-s for inwater sound) producing equal amounts of hearing impairment regardless of how the sound energy is distributed in time (NIOSH, 1998). Until recently, previous marine mammal TTS studies have also generally supported this equal energy relationship (Southall et al., 2007). Three newer studies, two by Mooney et al. (2009a,b) on a single bottlenose dolphin either exposed to playbacks of U.S. Navy mid-frequency active sonar or octave-band sound (4–8 kHz) and one PO 00000 Frm 00019 Fmt 4701 Sfmt 4702 55663 by Kastak et al. (2007) on a single California sea lion exposed to airborne octave-band sound (centered at 2.5 kHz), concluded that for all sound exposure situations, the equal energy relationship may not be the best indicator to predict TTS onset levels. Generally, with sound exposures of equal energy, quieter sound exposures (lower SPL) with longer duration were found to induce TTS onset more than those of louder (higher SPL) and shorter duration. Given the available data, the received level of a single seismic pulse (with no frequency weighting) might need to be approximately 186 dB SEL in order to produce brief, mild TTS. Data on TTS from continuous sound (such as that produced by Port Dolphin’s proposed activities) are limited, so the available data from seismic activities are used as a proxy. Exposure to several strong seismic pulses that each have received levels near 175–180 dB SEL might result in slight TTS in a small odontocete, assuming the TTS threshold is (to a first approximation) a function of the total received pulse energy. Given that the SPL is approximately 10–15 dB higher than the SEL value for the same pulse, an odontocete would need to be exposed to a SPL of 190 dB in order to incur TTS. TTS was measured in a single, captive bottlenose dolphin after exposure to a continuous tone with maximum SPLs at frequencies ranging from 4 to 11 kHz that were gradually increased in intensity to 179 dB and in duration to 55 minutes (Nachtigall et al., 2003). No threshold shifts were measured at SPLs of 165 or 171 dB. However, at 179 dB, TTSs greater than 10 dB were measured during different trials with exposures ranging from 47 to 54 minutes. Hearing sensitivity apparently recovered within 45 minutes after sound exposure. Although underwater sound levels produced by the Port Dolphin project may exceed levels produced in studies that have induced TTS in odontocetes, there is a general lack of controlled, quantifiable field studies related to this phenomenon, and existing studies have had varied results (Southall et al., 2007). Therefore, it is difficult to extrapolate from these data to site-specific conditions for the Port Dolphin project. For example, because most of the studies have been conducted in laboratories, rather than in field settings, the data are not conclusive as to whether elevated levels of sound will cause odontocetes to avoid the project area, thereby reducing the likelihood of TTS, or whether sound will attract them, increasing the likelihood of TTS. In any case, there are no universally E:\FR\FM\10SEP3.SGM 10SEP3 mstockstill on DSK4VPTVN1PROD with PROPOSALS3 55664 Federal Register / Vol. 77, No. 175 / Monday, September 10, 2012 / Proposed Rules accepted standards for the amount of exposure time likely to induce TTS. While it may be inferred that TTS could theoretically result from the proposed activities, it is impossible to exactly quantify the magnitude of exposure, the duration of the effect, or the number of individuals likely to be affected. Exposure is likely to be brief because the majority of proposed activities would be transient. It is expected that elevated sound would have only a negligible probability of causing TTS in individual odontocetes because (1) of the relatively low SPLs produced by most project activities; (2) the transient nature of most sounds produced by the activities; (3) the short duration of certain activities that are expected to produce higher SPLs (i.e., offshore pile driving); and (4) the location of the project in, primarily, offshore open waters where marine mammals may easily avoid areas of ensonification. PTS—When PTS occurs, there is physical damage to the sound receptors in the ear. In some cases, there can be total or partial deafness, whereas in other cases the animal has an impaired ability to hear sounds in specific frequency ranges. There is no specific evidence that exposure to underwater industrial sounds can cause PTS in any marine mammal (see Southall et al., 2007). However, given the possibility that marine mammals might incur TTS, there has been further speculation about the possibility that some individuals occurring very close to industrial activities might incur PTS. Richardson et al. (1995) hypothesized that PTS caused by prolonged exposure to continuous anthropogenic sound is unlikely to occur in marine mammals, at least for sounds with source levels up to approximately 200 dB. Single or occasional occurrences of mild TTS are not indicative of permanent auditory damage in terrestrial mammals. Relationships between TTS and PTS thresholds have not been studied in marine mammals but are assumed to be similar to those in humans and other terrestrial mammals. PTS might occur at a received sound level at least several decibels above that inducing mild TTS. Southall et al. (2007) propose that sound levels inducing 40 dB of TTS may result in onset of PTS in marine mammals. The authors present this threshold with precaution, as there are no specific studies to support it. Because direct studies on marine mammals are lacking, the authors base these recommendations on studies performed on other mammals. Additionally, the authors assume that multiple pulses of underwater sound VerDate Mar<15>2010 18:22 Sep 07, 2012 Jkt 226001 result in the onset of PTS in midfrequency cetaceans when levels reach 230 dB peak or 198 dB SEL; non-pulsed (continuous) sound would require levels of 230 dB peak or 215 dB SEL (Southall et al., 2007). Sound levels this high are not expected to occur as a result of the proposed activities. The potential effects to marine mammals described in this section of the document do not take into consideration the proposed monitoring and mitigation measures described later in this document (see the PROPOSED MITIGATION and PROPOSED MONITORING AND REPORTING sections). Because of the characteristics of sound produced by most construction activities (i.e., they are typically low intensity, non-pulsed, and transient), it is highly unlikely that marine mammals would receive sounds strong enough (and over a sufficient duration) to cause PTS (or even TTS). When taking the mitigation measures proposed for inclusion in the regulations into consideration (e.g., shutdown zones to prevent Level A harassment), it is highly unlikely that any type of hearing impairment would occur as a result of the proposed activities. Anticipated Effects on Habitat The proposed activities could have some impacts on marine mammal habitat, primarily by producing temporary disturbances through elevated levels of underwater sound, and to a lesser extent, temporarily reduced water quality and temporary and permanent physical habitat alteration. These impacts would not be expected to have tangible direct effects to marine mammals, but could result in minor effects to fish or other elements of the marine mammal prey base. Elevated levels of sound may be considered to affect the habitat of marine mammals through impacts to acoustic space (described in previous sections) or via impacts to prey species. The direct loss of habitat available during construction due to sound impacts is expected to be minimal. Seafloor Disturbance Installation of port components and pipelines would cause short- and longterm disruption of benthic habitat in the immediate vicinity of the construction areas; permanent alteration of benthic habitat would result from buoy anchor sweep during port operations. Destruction of bottom habitat, along with resident benthic organisms within the area, is an unavoidable component of pipeline installation. This affects not only the benthic communities, but also the fish assemblages that rely on those PO 00000 Frm 00020 Fmt 4701 Sfmt 4702 communities for food and/or shelter; these fish may in turn be preyed upon by marine mammals. Immediately upon cessation of disturbance, the substrate would be available for recruitment of benthic organisms and reestablishment of the community. The areas affected by seafloor disturbance are essentially negligible in comparison with the habitat available to marine mammals in the surrounding area. The pipeline route was selected to avoid marine protected areas and areas of submerged aquatic vegetation to the extent possible. During and shortly after installation of the buoy array components and the pipeline, marine mammal prey species are expected to avoid feeding in the immediate vicinity of the project area, thus reducing the utility of habitat in the area. Displaced organisms would likely return to the area shortly after construction activities cease. Turbidity Turbidity refers to any insoluble particulate matter suspended in the water column that impedes light passage by scattering and absorbing light energy. Decreased light penetration reduces the depth of the photic zone, in turn reducing the depth at which primary productivity could occur. Impacts to marine mammals would be indirect, resulting from impacts to prey species. Water turbidity appears to have little or no direct impact on bottlenose dolphins, which are regularly seen in turbid waters. Turbidity may adversely affect prey species by direct mortality or reduction of growth rates, modifying migration patterns, reducing available food abundance or habitat (in part by reducing primary production), or burial of benthic shellfish. However, these potential impacts would be spatially limited and shortterm in nature, as the suspended sediment would redeposit soon after the buoy system array and pipeline components were installed. Seawater Intake and Discharge During the construction phase, seawater would be used for hydrostatic testing of the offshore pipeline and flowlines. Hydrostatic testing is a onetime temporary event that would require filling the pipeline twice; a total of approximately 24 million gallons would be used. Hydrostatic integrity testing could nevertheless indirectly impact marine mammals, because plankton and fish larvae and eggs could be entrained and subsequently killed by the seawater intake system. This could have either primary or secondary indirect impacts E:\FR\FM\10SEP3.SGM 10SEP3 Federal Register / Vol. 77, No. 175 / Monday, September 10, 2012 / Proposed Rules mstockstill on DSK4VPTVN1PROD with PROPOSALS3 on marine mammals through impacts to prey species. During regasification, seawater would be taken into an SRV through one of two sea chests covered with a lattice screen. Similar to uptake described for hydrostatic testing, marine mammals may be indirectly impacted through the entrainment of plankton and fish eggs and larvae. Cooling water would be discharged at 10 °C (18 °F) above ambient seawater temperature, and would affect a relatively small area. The discharge would produce detectable temperature increases over a maximum radius of 106 m (348 ft). The cooling water discharge is not expected to reach the seafloor, and would thus not impact benthic communities. The cooling water plume would affect a relatively small area. Considering the short-term nature of impacts and the overall amount of plankton and fish eggs and larvae in the area, these impacts may be considered negligible. Sound Disturbance Elevated levels of sound produced by port construction and operation could potentially directly impact marine mammals by reducing the attractiveness of a given area for foraging, i.e., marine mammals may be less likely to forage in a given area in the presence of elevated levels of sound. In addition, sound may indirectly impact marine mammals through effects to fish or other prey species. However, sound produced by project activities is unlikely to be of sufficient intensity or duration to result in significant pathological, physiological, or behavioral effects to fish. All of the potential adverse impacts to marine mammal habitat would likely be indirect, and would result from impacts on the food web (i.e., adverse impacts directly to marine mammal prey species or to species lower in the food chain) from the proposed activities. The impact to marine mammals of temporary and permanent habitat changes from the proposed activities is expected to be minimal. Any potential impacts would likely be negligible relative to the amount of habitat available on the west Florida Shelf or in adjacent nearshore waters. These effects are summarized here: • Seafloor disturbance and turbidity: Marine mammals could be indirectly impacted if benthic prey species were displaced or destroyed. Affected species would be expected to recover after construction ceased, and would represent only a small portion of food available to marine mammals in the area. Indirect adverse impacts of limited spatial extent could occur as a result of VerDate Mar<15>2010 18:22 Sep 07, 2012 Jkt 226001 short- and long-term turbidity increases caused by construction and operations. • Seawater intake and discharge: This activity, primarily occurring during regasification, would result in the entrainment and destruction of plankton and larvae and discharge of heated seawater. The resulting adverse impact to the prey base would be negligible. • Sound disturbance: Elevated levels of sound during construction would cause temporary modification of habitat and could harm prey species, potentially reducing utility of habitat for marine mammal foraging. Elevated levels of sound during operation of the DWP would result in essentially permanent habitat modification to a limited area in the immediate vicinity of each STL buoy. In conclusion, NMFS has preliminarily determined that Port Dolphin’s proposed activities are not expected to have any habitat-related effects that could cause significant or long-term consequences for individual marine mammals or on the food sources that they utilize. Proposed Mitigation In order to issue an incidental take authorization under section 101(a)(5)(A) of the MMPA, NMFS must, where applicable, set forth the permissible methods of taking pursuant to such activity, and other means of effecting the least practicable adverse impact on such species or stock and their habitat, paying particular attention to rookeries, mating grounds, and areas of similar significance, and on the availability of such species or stock for taking for certain subsistence uses (where relevant). NMFS and Port Dolphin worked to devise a number of mitigation measures designed to minimize impacts to marine mammals to the level of least practicable adverse impact, described in the following and in Port Dolphin’s Marine Protected Species Management Plan; please see Appendix B of Port Dolphin’s application to review that plan in detail. In addition to the measures described later, Port Dolphin would employ the following standard mitigation measures: • All work would be performed according to the requirements and conditions of the regulatory permits issued by federal, state, and local governments. • Briefings would be conducted between the Port Dolphin project construction supervisors and the crew, protected species observer(s) (PSO), and acoustical monitoring team (when present) prior to the start of all discrete construction activities, and when new personnel join the work, to explain PO 00000 Frm 00021 Fmt 4701 Sfmt 4702 55665 responsibilities, communication procedures, marine mammal monitoring protocol, and operational procedures. • Port Dolphin would comply with all applicable equipment sound standards and ensure that all construction equipment has sound control devices no less effective than those provided on the original equipment. In addition, vessel crew and contractors would be required to minimize sound to the extent possible. Equipment and/or procedures used may include the use of enclosures and mufflers on equipment, minimizing the use of thrusters, and turning off engines and equipment when not in use. Additional mitigation measures, which are discussed in greater detail below, include the following: • Visual monitoring program (marine mammal watch); • Vessel strike avoidance measures; • Line and cable entanglement avoidance measures; and • Marine debris and waste management protocols. Monitoring and Shutdown The modeling results for acoustic zones of influence (ZOIs; described in following sections) were used to develop mitigation measures for the proposed activities. Those zones would initially be set at the distances derived through modeling (or be larger than those distances), but may be adjusted as necessary on the basis of acoustic monitoring conducted by Port Dolphin in order to verify source levels and local acoustic propagation characteristics (see Proposed Monitoring and Reporting, later in this document). The ZOIs effectively represent the mitigation zone that would be established around each activity to prevent Level A harassment and to monitor authorized Level B harassment of marine mammals. For each of the described proposed activities, a shutdown zone (to include areas where SPLs equal or exceed 180 dB rms) and a disturbance zone (defined as where SPLs equal or exceed 120 dB or 160 dB rms for non-pulsed or pulsed sound sources, respectively) would be established. Shutdown zones include all areas where the underwater SPLs are anticipated to equal or exceed the Level A (injury) harassment criteria for marine mammals and are used in concert with mitigation monitoring in order to prevent the occurrence of Level A harassment. Disturbance zones typically include all areas where the underwater SPLs are anticipated to equal or exceed the Level B (behavioral) harassment criteria. These are intended as zones in which occurrence of marine mammals would be noted and recorded as E:\FR\FM\10SEP3.SGM 10SEP3 55666 Federal Register / Vol. 77, No. 175 / Monday, September 10, 2012 / Proposed Rules mstockstill on DSK4VPTVN1PROD with PROPOSALS3 incidental take while also alerting PSOs to potential close approach to the shutdown zone. In actual practice, the disturbance zones are often so large as to make comprehensive monitoring and fine-scale behavioral observation impracticable. The initial shutdown and disturbance zones would be established based on the worst-case underwater sound modeled as described, although shutdown zones may be larger than the actual modeled distances. Please see the discussion of ‘‘Distance to Sound Thresholds’’ under ‘‘Description of Sound Sources,’’ previously in this document. Conservative shutdown zones would be employed in most instances. Impact pile driving (described later) and nonstationary activities would employ zones larger than what is predicted for the Level A harassment threshold. Radial distances to shutdown zones for HDD activities were predicted to be less than 10 m. For all activities, and regardless of modeled shutdown zone (applicable to HDD activities), all equipment would be shut down if any marine mammal enters a precautionary 100 yd (91 m) zone in order to avoid potential risk of vessel strike or direct interaction with equipment. However, these shutdown requirements would not be required for cases in which delphinids voluntarily make such close approaches to vessels (e.g., for bow riding). In addition, for scenarios in which the modeled sound source is a spread of vessels employed for a given construction task, the shutdown/ disturbance zone would be measured from the central vessel in the spread, or the vessel that is the primary sound producer if it is not the central vessel. In most cases, the disturbance zone is of sufficient size to make comprehensive monitoring impracticable, although PSOs would be aware of the size and location of the modeled zone and would record any observations made within the zone as takes. Radial distances to Level B thresholds range up to 12.6 km; please refer to Table 6 for those distances. Monitoring Protocols The established zones would be monitored by qualified PSOs for mitigation purposes, as described here. Port Dolphin’s marine mammal monitoring plan (see Appendix B of Port Dolphin’s application) would be implemented, requiring collection of sighting data for each marine mammal observed during the proposed construction activities described in this document. At least two PSOs would conduct monitoring of shutdown and VerDate Mar<15>2010 18:22 Sep 07, 2012 Jkt 226001 disturbance zones (as described previously) for all concurrent specified construction activities during daylight hours (civil dawn to civil dusk). PSOs would have no other duties for the duration of the watch. Shutdown and disturbance zones would be monitored from an appropriate vantage point that affords the PSOs an optimal view of the sea surface while not interfering with operation of the vessel or in-water activities. Full observation of the shutdown zone would occur for the duration of the activity. Monitoring would occur before, during, and after specified construction activity, beginning 30 minutes prior to initiation and concluding 30 minutes after the activity ends. If marine mammals are present within the shutdown zone prior to initiation, the start would be delayed until the animals leave the shutdown zone of their own volition, or until 30 minutes elapse without resighting the animal(s). PSOs will be on watch at all times during daylight hours when in-water operations are being conducted, unless conditions (e.g., fog, rain, darkness) make observations impossible. If conditions deteriorate during daylight hours such that the sea surface observations are halted, visual observations must resume as soon as conditions permit. While activities will be permitted during low-visibility conditions, they (1) must have been initiated following proper clearance of the ZOI under acceptable observation conditions; and (2) must be restarted, if halted for any reason, using the appropriate ZOI clearance procedures. If a marine mammal is observed approaching or entering the shutdown zone, the PSO will call for the immediate shutdown of in-water operations. The equipment operator must comply with the shutdown order unless human safety is at risk. Any disagreement must be resolved after the shutdown takes place. Construction operations would be discontinued until the animal has moved outside of the shutdown zone. The animal would be determined to have moved outside the shutdown zone through visual confirmation by a qualified PSO or after 15 minutes have elapsed since the last sighting of the animal within the shutdown zone. The following additional measures would apply to visual monitoring: • Monitoring would be conducted using binoculars and the unaided eye. The limits of the designated ZOI will be determined using binocular reticle or other equipment (e.g., electronic rangefinder, range stick). A GPS unit or range finder would be used for PO 00000 Frm 00022 Fmt 4701 Sfmt 4702 determining the observation location and distance to marine mammals and sound sources. • Each PSO would have a dedicated two-way radio for contact with the other PSO or field operations manager. Whenever a marine mammal species is observed, the PSO will note and monitor the position (including relative bearing and estimated distance to the animal) until the animal dives or moves out of visual range of the PSO. The PSO will continue to observe for additional animals that may surface in the area. Often, there are numerous animals that may surface at varying time intervals. Records will be maintained of all marine mammal species sightings in the area, including date and time, weather conditions, species identification, approximate distance from the activity, direction and heading in relation to the activity, and behavioral correlation to the activity. For animals observed in the shutdown zone, additional information regarding actions taken, such as duration of the shutdown, behavior of the animal, and time spent in the shutdown zone will be recorded. During pile driving activities, data regarding the type of pile driven (e.g., material construction and pile dimensions), type and power of the hammer used, number of cold starts, strikes per minute, and duration of the pile driving activities will be recorded. Monitoring would be conducted by qualified PSOs. In order to be considered qualified, PSOs must meet the following criteria: • Visual acuity in both eyes (correction is permissible) sufficient for discernment of moving targets at the water’s surface with ability to estimate target size and distance; use of binoculars may be necessary to correctly identify the target. • Advanced education in biological science, wildlife management, mammalogy, or related fields (bachelor’s degree or higher is required). • Experience and ability to conduct field observations and collect data according to assigned protocols (this may include academic experience). • Experience or training in the field identification of marine mammals, including the identification of behaviors. • Sufficient training, orientation, or experience with the construction operation to provide for personal safety during observations. • Writing skills sufficient to prepare a report of observations, including, but not limited to, the number and species of marine mammals observed; dates and times when in-water construction activities were conducted; dates and E:\FR\FM\10SEP3.SGM 10SEP3 Federal Register / Vol. 77, No. 175 / Monday, September 10, 2012 / Proposed Rules times when in-water construction activities were suspended to avoid potential incidental injury from construction sound of marine mammals observed within a defined shutdown zone; and marine mammal behavior. • Ability to communicate orally, by radio or in person, with project personnel to provide real-time information on marine mammals observed in the area as necessary. mstockstill on DSK4VPTVN1PROD with PROPOSALS3 Pile Driving Mitigation measures specific to pile driving would include use of (1) a sound attenuation device and (2) rampup procedures. In addition, the power of impact hammers will be reduced to minimum energy levels required to drive a pile, thus reducing the amount of sound produced in the marine environment. As for other construction activities, vibratory pile driving may continue into nighttime hours/lowvisibility conditions only if ramp-up protocols have been conducted under acceptable observation conditions. Impact pile driving may occur only during daylight hours of good visibility. In the event of a shutdown during lowvisibility conditions, the pile driving cannot resume until visual monitoring activities are resumed under acceptable observation conditions. The minimum shutdown zone for impact pile driving would be established conservatively at 250 m. One or more sound attenuation device will be utilized during all impact pile driving activities needed to install components of the STL buoys at the deepwater port. The sound attenuation device(s) will be selected and designed by the marine construction and design contractor(s), but would likely be either a bubble curtain or a temporary sound attenuation pile (TNAP), potentially used in conjunction with cushion block. Please see the discussion of ‘‘Sound Attenuation Devices’’ under ‘‘Description of Sound Sources,’’ previously in this document. The objective of a ramp-up is to alert any animals close to the activity and allow them time to move away, which would expose fewer animals to loud sounds. This procedure also ensures that any marine mammals missed during shutdown zone monitoring would move away from the activity and not be injured. The following ramp-up procedures would be used for in-water pile installation: • To allow any marine mammals that may be in the immediate area to leave before pile driving reaches full energy, a ramp-up technique would be used at the beginning of each day’s in-water pile VerDate Mar<15>2010 18:22 Sep 07, 2012 Jkt 226001 driving activities or if pile driving has ceased for more than 1 hour. • If a vibratory driver is used, contractors would be required to initiate sound from vibratory hammers for 15 seconds at reduced energy followed by a 1-minute waiting period. The procedure would be repeated two additional times before full energy may be achieved. • If a non-diesel impact hammer is used, contractors would be required to provide an initial set of strikes from the impact hammer at reduced energy, followed by a 1-minute waiting period, then two subsequent sets. • If a diesel impact hammer is used, contractors would be required to turn on the sound attenuation device (e.g., bubble curtain or other approved sound attenuation device) for 15 seconds prior to initiating pile driving to flush marine mammals from the area. Vessel Strike Avoidance Several construction and support vessels will be used during offshore construction activities. Certain vessel activities, including transits, may not be subject to the visual monitoring and shutdown protocols described previously in this section. Consequently, there is the possibility for vessel strike of protected species to occur within the project area. Port Dolphin would inform all personnel associated with the project of the potential presence of protected species. All vessel crew members and contractors would participate in training for protected species presence and emergency procedures in the unlikely event a protected species is struck by a vessel. Construction and support vessels will follow the NMFS Vessel Strike Avoidance Measures and Reporting for Mariners. Standard measures would be implemented to reduce the risk associated with vessel strikes. The following vessel strike mitigation measures for cetaceans for active construction/installation vessel operations would be implemented during project activities: • Vessel operators and crews must maintain a vigilant watch for marine mammals and slow down or stop their vessels, to the extent possible as dictated by safety concerns, to avoid striking sighted protected species. • Construction or support vessels, while underway, would remain 100 yd (91 m) from all marine mammals to the extent possible. • If a marine mammal is within 15 m of a construction or support vessel underway, all operations will cease until it is > 100 yd from the vessel. If the marine mammal is observed within PO 00000 Frm 00023 Fmt 4701 Sfmt 4702 55667 100 yd of an active construction or support vessel underway, the vessel would cease power to the propellers as long as sea conditions permit for safety. After the marine mammal leaves the area the vessel would proceed with caution, following the guidelines below: D Resume vessel at slow speeds while avoiding abrupt changes in direction, D Stay on parallel course with the marine mammal, following behind or next to at an equal or lesser speed, D Do not cross the path of the animal, D Do not attempt to steer or direct the marine mammal away, D If a marine mammal exhibits evasive or defensive behavior, stop the vessel until the marine mammal has left the immediate area, and D Do not allow the vessel to come between a mother and her calf. • Cetaceans can surface in unpredictable locations or approach slowly moving vessels. When an animal is sighted in the vessel’s path or in close proximity to a moving vessel, the Master would reduce speed and shift the engine to neutral and would not engage the engines until the animals are clear of the area. • If a sighted marine mammal is believed to be a North Atlantic right whale, federal regulation requires a minimum distance of 500 yd (457 m) from the animal be maintained (50 CFR 224.103 (c)). • Practical speeds would be maintained to the extent possible. Guidelines for speeds include the following: D Reduce vessel speed to 10 kn or less when mother/calf pairs, pods, or large assemblages of cetaceans are observed near an underway vessel, when safety permits. A single cetacean at the surface can indicate the presence of submerged animals in the vicinity of the vessel; therefore, prudent precautionary measures should always be exercised. D No wake/idle speeds where the draft of the vessel provides less than a 4-ft (1.2-m) clearance from the bottom. All vessels would follow deep-water routes whenever possible. D All construction vessels transiting to and from the port from shore would not exceed 14 kn during regular operations. D Avoid sudden changes in speed and direction. D Speeds approaching and departing the buoys would be reduced to 10 kn maximum. D Speeds during installation would be well under 14 kn; vessels may be stationary during certain phases of installation. • If a collision seems likely, emergency collision procedures would be followed. E:\FR\FM\10SEP3.SGM 10SEP3 55668 Federal Register / Vol. 77, No. 175 / Monday, September 10, 2012 / Proposed Rules mstockstill on DSK4VPTVN1PROD with PROPOSALS3 • Members of the vessel crew would be encouraged to undergo NMFS training prior to activity, including instruction in reporting procedures, collision emergency procedures, and marine mammal presence detection (surfacing near wake). • During construction of the facility, an Environmental Coordinator would be on site and responsible for communicating with NMFS and other relevant agencies, as appropriate. • During construction/installation, transiting vessels would have lookouts required to scan for surfacing marine mammals and report sightings to the Master, who would notify the Environmental Coordinator. • Offshore vessel activities not required to implement visual monitoring protocols described previously in this document would be temporarily terminated if marine mammals were observed in the area and there is the potential for harm of an individual. The Environmental Coordinator would be called in to determine the appropriate course of action. Best Management Practices Port Dolphin, in conjunction with NMFS and other regulatory agencies, has proposed a number of BMPs that will reduce project environmental impacts. Although these measures are not designed specifically to reduce project impacts on marine mammals to the level of least practicable adverse impact, they do have the effect of either directly or indirectly reducing the potential for adverse effects to marine mammals. These BMPs are briefly described here. See Port Dolphin’s application or Environmental Impact Statement for more details about these measures. Lighting—BMPs would be implemented to minimize the attraction of marine mammals to the project area and prevent potential impacts to protected species from nighttime lighting. Lighting would be downshielded to prevent unnecessary upward illumination while illuminating the vessel decks only. To the extent possible, they would not illuminate surrounding waters. Lighting used during all activities would be regulated according to USCG requirements, without using excessive wattage or quality of lights. Once an activity is completed, all lights used only for that activity would be extinguished. Entanglement—BMPs would be implemented to prevent entanglement in any lines or cables or siltation barriers used in any construction area. For example, lines, cables, and in-water VerDate Mar<15>2010 18:22 Sep 07, 2012 Jkt 226001 barriers would not be made of any materials in which a protected species can become entangled (e.g., monofilament), would be properly secured, and would be regularly monitored to avoid protected species entrapment. Marine Debris—BMPs would be implemented to prevent potential impacts to protected species from debris discarded within any construction area, including mandatory marine debris training consistent with Bureau of Ocean Energy Management, Regulation, and Enforcement (BOEMRE) NTL 2007– G03 Marine Trash and Debris Awareness and Elimination (http:// www.gomr.boemre.gov/homepg/ regulate/regs/ntls/2007NTLs/07-g03. pdf). Turbidity—Measures related to turbidity are designed to reduce project impacts to water quality in the marine environment. These include requirements to reduce sediment resuspension from pipeline trenching and burial through the use of certain technology. Benthic Habitat • Anchor locations would be optimized to minimize impacts on benthic habitat; avoidance zones would be identified of critical habitat areas for placement of installation barge anchors. An anchoring plan would be developed that would provide procedures for anchor deployment to minimize impacts on hard- and live-bottom habitat. • Required vessels would be selected to minimize the number and type of anchors, where possible, while still providing vessels adequate to perform the work. • Midline buoys would be utilized to the extent practicable on anchor chains to reduce the amount of anchor chain sweep. • A Mitigation Plan to compensate for unavoidable impacts on hard bottom would be developed. Pelagic Habitat—As described previously in this document, SRV seawater intake/discharge and other vessel discharge protocols would be designed to minimize impacts to water column habitat by reducing seawater intake requirements, creating limits for seawater intake velocity and discharge temperature, and reducing other vessel discharges. Conclusions NMFS has carefully evaluated the applicant’s proposed mitigation measures and considered a range of other measures in the context of ensuring that NMFS prescribes the means of effecting the least practicable PO 00000 Frm 00024 Fmt 4701 Sfmt 4702 adverse impact on the affected marine mammal species and stocks and their habitat. Our evaluation of potential measures included consideration of the following factors in relation to one another: • The manner in which, and the degree to which, the successful implementation of the measure is expected to minimize adverse impacts to marine mammals; • The proven or likely efficacy of the specific measure to minimize adverse impacts as planned; and • The practicability of the measure for applicant implementation. Based on our evaluation of the applicant’s proposed measures and the measures added by NMFS, NMFS has preliminarily determined that the mitigation measures proposed by both NMFS and Port Dolphin provide the means of effecting the least practicable adverse impact on marine mammal species or stocks and their habitat, paying particular attention to rookeries, mating grounds, and areas of similar significance. The proposed rule comment period will afford the public an opportunity to submit recommendations, views, and/or concerns regarding this action and the proposed mitigation measures. While NMFS has determined preliminarily that the proposed mitigation measures presented in this document would effect the least practicable adverse impact on the affected species or stocks and their habitat, NMFS will consider all public comments to help inform the final decision. Consequently, the proposed mitigation measures may be refined, modified, removed, or added to prior to the issuance of the final rule based on public comments received, and where appropriate, further analysis of any additional mitigation measures. Proposed Monitoring and Reporting In order to issue an incidental take authorization (ITA) for an activity, section 101(a)(5)(A) of the MMPA states that NMFS must, where applicable, set forth ‘‘requirements pertaining to the monitoring and reporting of such taking.’’ The MMPA implementing regulations at 50 CFR 216.104(a)(13) indicate that requests for ITAs must include the suggested means of accomplishing the necessary monitoring and reporting that would result in increased knowledge of the species and of the level of taking or impacts on populations of marine mammals that are expected to be present in the proposed action area. Port Dolphin proposed a protected species monitoring plan in their application (see Appendix B of Port E:\FR\FM\10SEP3.SGM 10SEP3 mstockstill on DSK4VPTVN1PROD with PROPOSALS3 Federal Register / Vol. 77, No. 175 / Monday, September 10, 2012 / Proposed Rules Dolphin’s application). The plan may be modified or supplemented based on comments or new information received from the public during the public comment period. All monitoring methods identified herein have been developed through coordination between NMFS and Port Dolphin. The methods are based on the parties’ professional judgment supported by their collective knowledge of marine mammal behavior, site conditions, and proposed project activities. Any modifications to this protocol would be coordinated with NMFS. A summary of the plan, as well as the proposed reporting requirements, is contained here. The intent of the monitoring plan is to: • Comply with the requirements of the MMPA Letter of Authorization as well as the ESA section 7 consultation; • Avoid injury to marine mammals through visual monitoring of identified shutdown zones; and • To the extent possible, record the number, species, and behavior of marine mammals in disturbance zones for the proposed activities. As described previously, monitoring for marine mammals would be conducted in specific zones established to avoid or minimize effects of elevated levels of sound created by the specified activities. Initial shutdown and disturbance zones would be based on the applicant’s modeled values. Shutdown zones for non-stationary activities would conform to NMFS Vessel Strike Avoidance Measures and Reporting for Mariners (i.e., 100 yd)—a distance much larger than actual areas ensonified to 180 dB rms or greater. However, shutdown requirements would not be triggered upon voluntary approach by small marine mammals (i.e., delphinids). The actual zone monitored for disturbance would be based upon logistical considerations, as described previously in this document, as the full disturbance zones would be so large as to make monitoring impracticable. Zones may be modified on the basis of actual recorded SPLs from acoustic monitoring. Port Dolphin proposed a visual monitoring program in its application. In cooperation with NMFS, Port Dolphin has supplemented that plan with an acoustic monitoring program that would be conducted primarily to verify the sound source levels and local acoustic propagation characteristics that were assumed in the acoustic modeling. Acoustic Monitoring Port Dolphin would implement an acoustic monitoring program during VerDate Mar<15>2010 18:22 Sep 07, 2012 Jkt 226001 construction and operation of the deepwater port and appurtenant marine facilities. Please see Port Dolphin’s Sound Level Verification Plan (see Supplemental Information) for more detail. The objectives of this program are to: (1) Empirically measure the sound source levels associated with project activities and verify estimated source levels used in modelling, and (2) empirically determine ranges to relevant threshold levels, verifying the accuracy of the acoustic propagation model that was used to predict the size of sound fields generated by construction and operation of the port. Ambient sound levels would also be measured when no project activities are occurring. Source level measurements would be made using a combination of bottom deployed autonomous multi-channel acoustic recorders (AMARs) and cabled acoustic data acquisition and monitoring systems (ADAMs), and would require that accurate measurements of distance from source to the monitoring hydrophones be made. Range measurements are required for scaling the measured levels to a standard reference range (typically one meter from the source). Range measurements would be performed using a combination of GPS, radar and laser range finders. Both systems would obtain measurements at 1.5 m (5 ft) above the sea floor, with the depth of the hydrophones determined using collocated pressure-sensitive depth gauges. The hydrophone depth measurement is accurate to within 1 m. Received sound levels would be measured at pre-determined distances (as specified here) and would be used to determine site-specific propagation characteristics and verify ranges to the relevant sound exposure thresholds. The recording system would have a frequency response of ±3 dB from 10 Hz to 64,000 Hz over the anticipated measurement range of 100 dB to 220 dB (linear peak re: 1 mPa). Hydrophones with differing sensitivities may be required at different locations depending upon the acoustic environment and source to be measured. Analysis of the recorded data would determine the amplitude, time history, and frequency of sounds associated with construction activity. Acoustic data to be reported include: • Mean squared pressure (integral of the squared pressure for duration of impulse, divided by the impulse duration; dB re: 1 mPa2/s, rms) for pulsed sounds; • SPL (dB re: 1 mPa, rms) for nonpulsed sounds; • The maximum averaging time and representative range of SPLs; PO 00000 Frm 00025 Fmt 4701 Sfmt 4702 55669 • Representative range of frequency spectra; 1/3rd octave band center frequency SPLs dB re:1 mPa measured over the frequency range of 10 Hz to 64,000 Hz; and • Peak SPL (dB re: 1 mPa; the largest absolute value of the instantaneous sound pressure over the minimum frequency range of 10 Hz to 64,000 Hz). The maximum and representative range of peak SPLs would be recorded for each activity. The activities to be monitored are: • Pipelaying activities; • Pipeline burial using the plow system and dredging; • Pile driving at the buoy locations; • Installation of the STL buoys; • HDD within Tampa Bay; • Vibratory driving (if conducted); and • SRV maneuvering and docking. Verification of sound source levels emitted by each of the various activities is required. Although most types of construction activity would be conducted at more than one location and on more than one occasion during the construction period, it is only necessary to determine their sound source level once because local acoustic propagation characteristics should have little effect on the source level calculation. Some construction activities are of long duration and may vary in source level during the operation. For these longer-duration activities (i.e., pipelaying and burial, HDD), a sound level monitoring program of 7 days of continuous recording at a sample rate of 128 kHz would be implemented to capture and consider potential variability when determining the source level associated with these activities. During the 7-day program, logs of the various activities would be collected, permitting a correlation between the activities occurring and the sound levels recorded. For all construction activities, sound level monitoring stations would consist of bottom deployed autonomous recorders at ranges of 500, 1,000 and 1,500 m, perpendicular to the construction spread’s direction of travel when applicable. In addition a cabled recording system would be deployed from the appropriate vessel in order to capture close range data suitable for determining a source level estimate. The distances and directions of any of these sound monitoring locations from the activity may be changed if, in the opinion of either Port Dolphin or the marine construction contractors, activities at the planned monitoring locations could pose health and safety risks or impede vessels or construction. If the locations must be changed, the E:\FR\FM\10SEP3.SGM 10SEP3 mstockstill on DSK4VPTVN1PROD with PROPOSALS3 55670 Federal Register / Vol. 77, No. 175 / Monday, September 10, 2012 / Proposed Rules monitoring would occur at the safest location that is closest to the proposed location that would not interfere with vessels or construction. Specific details of monitoring locations for each activity type are discussed in the next paragraph. For dredging, Port Dolphin is planning to monitor the operation at either the exit or entry pit dredges of the western Gulfstream HDD. The proposed HDD locations are drilling from land to water at the Port Manatee shore approach and from water-to-water at two crossings of the Gulfstream pipeline. Port Dolphin is planning to monitor the HDD operations at the entry pit of the western Gulfstream HDD. For the pipeline laying, plowing and backfilling the pipeline trench, Port Dolphin plans to conduct the sound level verification in the Sarasota Bay Estuarine System. During these activities, the construction spread would be moving relative to the acoustic monitoring stations. This would provide a more detailed record of data on received sounds levels as a function of range and direction from the construction spread. The commissioning of a new SRV type (i.e., different cargo containment capacity) at the port may involve the unloading of more than one shipment of LNG through the port. The sound level verification program is planned to be implemented only once for each new SRV type during the approach, unloading, and departure during the first commissioning shipment. Once the SRV completes its approach to Port Dolphin and is within approximately 5.6 km of the Port, bow and stern thrusters would be utilized. Thruster use would vary, operating for 10 to 30 minutes to allow for the proper positioning of the vessel and allow for connection to the STL buoy. Docking or berthing is expected to occur at alternate STL buoys approximately every 8 days. The monitoring program would consist of a similar combination of autonomous and cabled acoustic recorders as outlined here. For SRV maneuvering (i.e., approach, docking, unloading, undocking and departure) operations, Port Dolphin would establish four sound level measuring stations. As part of the DWPL issued by the MarAd, a safety zone, an area to be avoided (ATBA), and a noanchoring zone have been established around the deepwater port. The boundary of the safety zone has been set at a distance of 850 m (2,790 ft) from both the northern and southern STL buoys. The boundaries of both the ATBA and no-anchoring zone have been VerDate Mar<15>2010 18:22 Sep 07, 2012 Jkt 226001 set at 1,500 m (4,925 ft) from both the northern and southern STL buoy. For the SRV maneuvering to docking/ undocking at and departure from the two STL buoys, the sound level verification measurements would be taken at the boundary of the ATBA. Three bottom-deployed autonomous recording stations would therefore be set at a distance of 1,500 m from the STL buoys. This would ensure that sufficient data is collected regardless of the SRV’s specific approach to the STL buoy. In addition, a fourth autonomous system would be deployed on a platform directly below the STL buoy. The recording system used here would have a frequency response of ±1 dB from 10 Hz to 20,000 Hz over the anticipated measurement range of 100 dB to 220 dB (linear peak re: 1 mPa) due to the lower frequencies expected. Visual Monitoring Visual monitoring of relevant zones would be conducted as described previously (see ‘Proposed Mitigation’). Shutdown or delay of activities would occur as appropriate. The monitoring biologists would document all marine mammals observed in the monitoring area. Data collection would include a count of all marine mammals observed by species, sex, age class, their location within the zone, and their reaction (if any) to construction activities, including direction of movement, and type of construction that is occurring, time that activity begins and ends, any acoustic or visual disturbance, and time of the observation. Environmental conditions such as wind speed, wind direction, visibility, and temperature would also be recorded. No monitoring would be conducted during inclement weather that creates potentially hazardous conditions, as determined by the PSO(s). No monitoring would be conducted when visibility is significantly limited, such as during heavy rain or fog. During these times of inclement weather, in-water work that may produce sound levels in excess of 180 dB rms may continue, but may not be started. Impact pile driving shall not occur when visibility is significantly limited. All monitoring personnel must have appropriate qualifications as identified previously. These qualifications include education and experience identifying marine mammals and the ability to understand and document marine mammal behavior. All monitoring personnel would meet at least once for a training session provided by Port Dolphin, and Port Dolphin would be responsible for verifying to NMFS that PSOs meet the minimal qualifications PO 00000 Frm 00026 Fmt 4701 Sfmt 4702 described previously. Topics would include, at minimum, implementation of the monitoring protocol, identification of marine mammals, and reporting requirements. All monitoring personnel would be provided a copy of the LOA. Monitoring personnel must read and understand the contents of the LOA as they relate to coordination, communication, and identifying and reporting incidental harassment of marine mammals. All sightings must be recorded on approved marine mammal field sighting logs. Proposed Reporting Reports of data collected during monitoring would be submitted to NMFS weekly. In addition, a final report summarizing all marine mammal monitoring and construction activities would be submitted to NMFS annually. The report would include: • All data described previously under monitoring, including observation dates, times, and conditions; and • Correlations of observed behavior with activity type and received levels of sound, to the extent possible. Port Dolphin would also submit a report(s), as necessary, concerning the results of all acoustic monitoring. The final report for acoustic monitoring of construction activities would be provided at the completion of all marine construction activities. Reporting for acoustic monitoring of operational activities would be provided at the completion of the commissioning period for each new SRV servicing the port. Port Dolphin would to submit these reports to NMFS within 60 working days of the completion of each monitoring event. Acoustic monitoring reports would include: • A detailed description of the monitoring protocol; • A description of the sound monitoring equipment; • Documentation of calibration activities; • The depth of water at the hydrophone locations and the depth of the hydrophones; • The background SPL reported as the 50 percent cumulative density function; • A summary of the data recorded during monitoring; and • Analysis of the recorded data and conclusions. Analysis of the data should include the frequency spectrum, ranges and means including the standard deviation/ error for the peak and rms SPLs, and an estimation of the distance at which rms values reach the relevant marine mammal thresholds and background sound levels. Vibratory driving results E:\FR\FM\10SEP3.SGM 10SEP3 mstockstill on DSK4VPTVN1PROD with PROPOSALS3 Federal Register / Vol. 77, No. 175 / Monday, September 10, 2012 / Proposed Rules would include the maximum and overall average rms calculated from 30s rms values during driving of the pile. In addition, for pile driving, the report would include: • Size and type of any piles driven, correlated with SPLs; • A detailed description of any sound attenuation device used, including design specifications; • The impact hammer energy rating used to drive the piles, make and model of the hammer(s), and description of the vibratory hammer; • The physical characteristics of the bottom substrate into which the piles were driven; and • The total number of strikes to drive each pile. During all phases of construction activities and operation, sightings of any injured or dead marine mammals will be reported immediately (except as described later in this section) to the NMFS Southeast Region Marine Mammal Stranding Network, regardless of whether the injury or death is caused by project activities. In addition, if a marine mammal is struck by a project vessel (e.g., SRV, support vessel), or in the unanticipated event that project activity clearly resulted in the injury, serious injury, or death (e.g., gear interaction, and/or entanglement) of a marine mammal, USCG and NMFS must be notified immediately, and a full report must be provided to NMFS, Southeast Regional Office, and NMFS, Office of Protected Resources. The report must include the following information: (1) The time, date, and location (latitude/longitude) of the incident; (2) the name and type of vessel involved, if applicable; (3) the vessel’s speed during and leading up to the incident, if applicable; (4) a description of the incident; (5) water depth; (6) environmental conditions (e.g., wind speed and direction, sea state, cloud cover, visibility); (7) the species identification or description of the animal(s) involved; (8) the fate of the animal(s); and (9) photographs or video footage of the animal (if equipment is available). Following such an incident, activities must cease until NMFS is able to review the circumstances of the incident. NMFS would work with Port Dolphin to determine what is necessary to minimize the likelihood of further prohibited take and ensure MMPA compliance. Port Dolphin may not resume activity until notified to do so by NMFS. If a prohibited take should occur, the NMFS Office of Law Enforcement and the Florida Fish and Wildlife Conservation Commission law enforcement would be notified. VerDate Mar<15>2010 18:22 Sep 07, 2012 Jkt 226001 In the event that an injured or dead marine mammal is discovered, and the lead PSO determines that the cause of the injury or death is unknown and the death is relatively recent (i.e., in less than a moderate state of decomposition as described in the next paragraph), Port Dolphin will immediately report the incident to NMFS, Office of Protected Resources. The report must include the same information identified in the preceding paragraph. However, activity may continue while NMFS reviews the circumstances of the incident, and NMFS will work with Port Dolphin to determine whether modifications to the activities are appropriate. If the lead PSO determines that the discovered animal is not associated with or related to project activities (e.g., previously wounded animal, carcass with moderate to advanced decomposition, scavenger damage), Port Dolphin would report the incident to NMFS, Office of Protected Resources, within 24 hours of the discovery. Port Dolphin should provide photographs or video footage (if available) or other documentation of the sighting. Activities may continue while NMFS reviews the circumstances of the incident. An annual report on marine mammal monitoring and mitigation would be submitted to NMFS, Office of Protected Resources, and NMFS, Southeast Regional Office, each year. The weekly and annual reports would include data collected for each distinct marine mammal species observed in the project area. Description of marine mammal behavior, overall numbers of individuals observed, frequency of observation, and any behavioral changes and the context of the changes relative to activities would also be included in the annual reports. Additional information that would be recorded during activities and contained in the reports include: date and time of marine mammal detections, weather conditions, species identification, approximate distance from the source, and activity at the construction site when a marine mammal is sighted. In addition to annual reports, Port Dolphin would submit a draft comprehensive final report to NMFS, Office of Protected Resources, and NMFS, Southeast Regional Office, 180 days prior to the expiration of the regulations. This comprehensive technical report would provide full documentation of methods, results, and interpretation of all monitoring during the first 4.5 years of the regulations. A revised final comprehensive technical report, including all monitoring results during the entire period of the regulations would be due 90 days after PO 00000 Frm 00027 Fmt 4701 Sfmt 4702 55671 the end of the period of effectiveness of the regulations. Adaptive Management The final regulations governing the take of marine mammals incidental to the specified activities at Port Dolphin would contain an adaptive management component. In accordance with 50 CFR 216.105(c), regulations for the proposed activity must be based on the best available information. As new information is developed, through monitoring, reporting, or research, the regulations may be modified, in whole or in part, after notice and opportunity for public review. The use of adaptive management would allow NMFS to consider new information from different sources to determine if mitigation or monitoring measures should be modified (including additions or deletions) if new data suggest that such modifications are appropriate for subsequent LOAs. The following are some of the possible sources of applicable data: • Results from Port Dolphin’s monitoring from the previous year; • Results from general marine mammal and acoustics research; or • Any information which reveals that marine mammals may have been taken in a manner, extent or number not authorized by these regulations or subsequent LOAs. If, during the effective dates of the regulations, new information is presented from monitoring, reporting, or research, these regulations may be modified, in whole, or in part after notice and opportunity of public review, as allowed for in 50 CFR 216.105(c). In addition, LOAs would be withdrawn or suspended if, after notice and opportunity for public comment, the Assistant Administrator finds, among other things, that the regulations are not being substantially complied with or that the taking allowed is having more than a negligible impact on the species or stock, as allowed for in 50 CFR 216.106(e). That is, should substantial changes in marine mammal populations in the project area occur or monitoring and reporting show that Port Dolphin actions are having more than a negligible impact on marine mammals, then NMFS reserves the right to modify the regulations and/or withdraw or suspend LOAs after public review. Estimated Take by Incidental Harassment Except with respect to certain activities not pertinent here, the MMPA defines ‘‘harassment’’ as: ‘‘any act of pursuit, torment, or annoyance which (i) has the potential to injure a marine E:\FR\FM\10SEP3.SGM 10SEP3 mstockstill on DSK4VPTVN1PROD with PROPOSALS3 55672 Federal Register / Vol. 77, No. 175 / Monday, September 10, 2012 / Proposed Rules mammal or marine mammal stock in the wild [Level A harassment]; or (ii) has the potential to disturb a marine mammal or marine mammal stock in the wild by causing disruption of behavioral patterns, including, but not limited to, migration, breathing, nursing, breeding, feeding, or sheltering [Level B harassment].’’ Take by Level B harassment only is anticipated as a result of Port Dolphin’s proposed activities. Take of marine mammals is anticipated to occur as a result of elevated levels of sound from the previously described activities associated with construction and installation of the port and from port operations. No take by injury, serious injury, or death is anticipated. As described previously in the ‘‘Distance to Sound Thresholds’’ section of this document, JASCO Research modeled a series of scenarios that thoroughly characterize the various construction/installation and operation activities expected. JASCO used proxy sound sources selected from a database of underwater sound measurements. The selected proxy sound sources were input to a sound propagation model with multiple parameters, including expected water column sound speeds, bathymetry, and bottom geoacoustic properties, to estimate the radii of sound impacts (JASCO, 2008, 2010). Note that for some scenarios, 180-dB threshold values only occur in the immediate vicinity of individual pieces of equipment that combine to form a construction ‘‘spread,’’ or modeled scenario, with little or no overlap of the sound fields from neighboring vessels. These scenarios are for transient activities—for example, pipelaying and burial activities require a spread of vessels and equipment (e.g., barges, tugs) rather than a single point source of sound. These modeled scenarios combine the sound output from multiple vessels/pieces of equipment. The overall radius depends primarily on the spacing between the vessels, and a single scenario-specific radius for the 180-dB threshold cannot sensibly be defined. All activity types considered here would produce sound source levels attenuating to less than 180 dB within 200 m; thus, 200 m is used as a conservative estimator for 180-dB area calculations in most cases. JASCO’s modeling reports the radial distance from each modeled source to received levels in 10 dB increments (i.e., from 120 dB through 180 dB), and this information is used here to report the intensity of sound source levels relative to this 200 m radius in subsequent sections. Please see Appendices C and D in Port Dolphin’s application for a VerDate Mar<15>2010 18:22 Sep 07, 2012 Jkt 226001 detailed description of this sound source modeling and Appendix E for a graphical depiction of the sound fields from various activities. Results of the modeled underwater analysis for Port Dolphin construction and operation are summarized as follows: • Buoy installation: Installation of the buoys at the Port would produce continuous, transient (non-pulsed) sound for a relatively short period of time during summer, with 120-dB isopleths located 3.9 km from each STL buoy location and corresponding ensonification of approximately 48 km2. At 200 m distance, sound produced by buoy installation would attenuate to less than 150 dB. • Pipelaying: Pipelaying activities would generate continuous (non-pulsed) sound, and would be transient as the pipelaying operation moved along the pipeline route. Construction is expected to occur during summer and fall. Depending on location, the 120-dB isopleth for pipelaying activities would extend either 6.0 (offshore) or 7.5 km (inshore) from the source, encompassing approximately 113 or 178 km2, respectively. At 200 m distance, sound produced by pipelaying would attenuate to less than 160 dB. • Pipeline burial: Pipeline burial using the plow system would generate continuous, transient sound during construction similar to pipelaying and is expected to occur during fall and winter. Pipeline burial would only be used in those locations with suitable substrate conditions. Distances to the 120-dB isopleth would be 6.7 (offshore) or 8.4 km (inshore) from the source and would encompass approximately 141 or 222 km2. At 200 m distance, sound produced by pipeline burial would attenuate to less than 160 dB. • Pile driving: Offshore installation of anchors via impact pile driving is slated to occur during summer. This impulsive sound source would produce a 160-dB isopleth at 4.5 km from each STL buoy location, encompassing approximately 64 km2. The 180-dB isopleths would extend to 180 m from the source, encompassing approximately 0.1 km2. • HDD: Horizontal directional drilling within Tampa Bay would produce continuous, non-pulsed sound and is expected to occur during summer. The 120-dB isopleth would extend 240 m from the drilling operation, encompassing approximately 0.2 km2. Calculations based on the area of ensonification for HDD indicate that no marine mammals would be harassed as a result of this activity. Source levels for this activity are expected to be below the 180-dB threshold; therefore, PO 00000 Frm 00028 Fmt 4701 Sfmt 4702 consideration of Level A harassment is not relevant. • HDD vibratory driving: Installation of the goal posts at each HDD location would produce continuous, non-pulsed sound for a relatively short period of time, exclusively during summer. The 120-dB isopleth for HDD vibratory driving would extend 12.6 km from the source, encompassing approximately 499 km2. The 180-dB isopleths would be less than 10 m from the source. • SRV maneuvering: Once an SRV completes its approach to Port Dolphin and is within approximately 5.6 km of the port, bow and stern thrusters would be utilized. Thruster use would vary, operating for 10 to 30 minutes to allow for the proper positioning of the vessel and connection to the STL buoy. Docking or berthing would occur at alternate STL buoys approximately every 8 days. The periodic use of the thrusters would produce continuous, non-pulsed sound that would be transient as the vessel moves, with the 120-dB isopleth occurring at 3.6 km from the SRV, encompassing approximately 41 km2. The 180-dB isopleths would be less than 10 m from the source. • Regasification: SRVs would regasify LNG cargo while docked at a STL buoy, producing continuous, non-pulsed sound. Sound levels for regasification are low, with the 120-dB isopleth at 170 m from the source, encompassing approximately 0.09 km2. Calculations based on this area of ensonification indicate that no marine mammals would be harassed as a result of this activity. Source levels for this activity are below the 180-dB threshold. Density of marine mammals in the project area was derived from a U.S. Navy review of available marine mammal survey data for the eastern Gulf of Mexico which summarized species presence and distribution on a seasonal basis (USDON, 2003). As described previously, marine mammal densities are determined on the basis of both seasonality and depth stratum. While the area of actual construction and operations for Port Dolphin is entirely contained within the nearshore depth stratum (0 to 37 m), the sound field from certain construction activity, and thus the area of effect, extends into the midshelf depth stratum (37 to 91 m). This has implications for the species of marine mammals that may potentially be affected by the activity. Almost all sound produced by construction activities would occur within the nearshore stratum. The only activity with a sound field extending to the midshelf depth stratum is offshore pipelaying, which would occur only E:\FR\FM\10SEP3.SGM 10SEP3 55673 Federal Register / Vol. 77, No. 175 / Monday, September 10, 2012 / Proposed Rules during construction, from approximately late summer 2013 through early winter 2013–14. The Level B sound field for this activity would be 99.9 percent contained within the nearshore stratum, with 0.1 percent projected to enter the mid-shelf stratum. Densities for marine mammals that may be affected by the proposed activities are presented in Table 8. TABLE 8—DENSITY ESTIMATES FOR MARINE MAMMALS IN THE NEARSHORE AND MID-SHELF DEPTH STRATA, EASTERN GOM Density (Individuals/100 km2 (39 mi2)) Species Winter Nearshore depth stratum: Atlantic spotted dolphin ............................................................................ Bottlenose dolphin .................................................................................... Mid-shelf depth stratum: Atlantic spotted dolphin ............................................................................ Bottlenose dolphin .................................................................................... Dwarf/pygmy sperm whale ....................................................................... Rough-toothed dolphin ............................................................................. Spring Summer Fall 2.243 10.913 10.752 21.986 2.524 8.241 10.752 26.744 11.630 7.410 0.000 0.000 21.699 2.588 0.011 0.000 17.354 11.707 0.011 0.000 22.916 10.856 0.000 0.400 Source: USDON, 2003. Incidental take estimates are calculated based on: (1) The number of marine mammals that occur within each respective depth stratum, using speciesand season-specific density estimates; (2) the percentage of sound field within each depth stratum, by source (this is relevant for offshore pipelaying only); (3) the areal extent of Level A and Level B sound fields, by sound source; and (4) the time or distance component of the activity. Areas of ensonification, by appropriate threshold, are presented in Table 6. With regard to the fourth component (time/distance), there are two types of construction activities: stationary and transient. Stationary activities would occur near specific sites (e.g., locations for buoy installation), while transient activities would occur while traveling along a pre-determined trackline (i.e., the pipeline route). Incidental take associated with stationary activities is determined by considering the estimated number of days of effect. Buoy installation, impact pile driving, and vibratory pile driving activities are expected to take 6, 32, and 8 days, respectively. The predetermined pipeline route along which the pipelaying and burial activities would occur is approximately 72 km long (37 km offshore, 35 km inshore). For these transient activities, the overall area of effect (i.e., distance × width of ensonified area) is used in calculating estimated incidental take. For stationary activities, seasonspecific estimated take was determined by first multiplying the modeled ZOI (i.e., the area ensonified using the appropriate thresholds) and the appropriate species-specific seasonal densities within each depth stratum (USDON, 2003). These results were then rounded to the nearest whole number and multiplied by the estimated number of days of effect to provide an estimate of take. For transient activities, seasonspecific estimated take was determined by multiplying the overall area of effect for offshore and inshore portions, respectively, by the appropriate density and, because some of these activities are expected to occur during multiple seasons, by the proportion of trackline expected to be completed during a given season. For offshore pipelaying, approximately 43 percent of effort is expected to occur during summer and 57 percent occur during fall. The inshore portion would occur entirely during fall. For offshore pipe burial, approximately 12 percent of effort is expected to occur during fall and 88 percent occurring during winter. The inshore portion would occur entirely during winter. For offshore pipelaying, the estimated take within each depth stratum was then integrated into the seasonal, species-specific calculations. Calculations indicate that, on the basis of the densities shown in Table 8 and the 0.1 percent of the sound field for pipelaying that would occur in the midshelf depth stratum, no incidental take of dwarf/pygmy sperm whales (i.e., Kogia spp.) or rough-toothed dolphins would occur. Similarly, take of spotted and bottlenose dolphins would occur only in the nearshore depth stratum (i.e., the 0.1 percent of effect occurring in the mid-shelf depth stratum would not add to the total take). Dwarf/pygmy sperm whales and rough-toothed dolphins are not covered by this proposed rule because incidental take is not anticipated, and no incidental take is proposed to be authorized. The results of take estimation calculations for bottlenose dolphins and spotted dolphins for construction activities are shown in Table 9. TABLE 9—ESTIMATED INCIDENTAL TAKE, CONSTRUCTION ACTIVITIES Species mstockstill on DSK4VPTVN1PROD with PROPOSALS3 Activity Season Buoy installation ............................................................................................................................ Impact pile driving ......................................................................................................................... Pipelaying—Offshore ..................................................................................................................... Summer ....... Summer ....... Summer ....... Fall ............... Fall ............... Fall ............... Winter ........... Winter ........... Pipelaying—Inshore ...................................................................................................................... Pipeline burial—Offshore .............................................................................................................. Pipeline burial—Inshore ................................................................................................................ VerDate Mar<15>2010 18:22 Sep 07, 2012 Jkt 226001 PO 00000 Frm 00029 Fmt 4701 Sfmt 4702 E:\FR\FM\10SEP3.SGM 10SEP3 Atlantic spotted dolphin 6 64 6 34 45 8 12 11 Bottlenose dolphin 24 160 20 85 112 20 60 51 55674 Federal Register / Vol. 77, No. 175 / Monday, September 10, 2012 / Proposed Rules TABLE 9—ESTIMATED INCIDENTAL TAKE, CONSTRUCTION ACTIVITIES—Continued Species Activity Season Vibratory pile driving ...................................................................................................................... Summer ....... 104 328 Total, by species .................................................................................................................... ...................... 290 860 When the Port reaches operational status, an estimated 46 SRV visits would occur per year. Visits would be equally distributed across seasons, with 12 visits expected during winter and summer seasons and 11 visits per season during spring and fall. Each visit includes arrival and departure of the SRV, so 46 visits would result in 92 episodes that may result in incidental Atlantic spotted dolphin Bottlenose dolphin take. The results of take estimation calculations for operational activities, for a given year, are shown in Table 10. TABLE 10—ESTIMATED YEARLY INCIDENTAL TAKE, PORT OPERATIONS Atlantic spotted dolphin Activity Season Bottlenose dolphin Trips Single visit 1 Single visit 1 Seasonal Seasonal SRV maneuvering ..................................... Summer ....... Fall ............... Winter ........... Spring ........... 12 11 12 11 2 9 2 9 24 99 24 99 7 22 9 18 84 242 108 198 Totals 2 ................................................ ...................... 46 ........................ 246 ........................ 632 1 Single-visit take calculated by multiplying appropriate density and appropriate area, then doubling the result to account for arrival and departure of the SRV in a single trip. 2 Total represents the single visit take multiplied by the total number of trips. mstockstill on DSK4VPTVN1PROD with PROPOSALS3 Assuming that this proposed rulemaking would be in effect during 1 year of construction and 4 years of operations, the total estimated taking, by Level B harassment only, would be 1,274 Atlantic spotted dolphins and 3,388 bottlenose dolphins. Negligible Impact and Small Numbers Analysis and Preliminary Determination NMFS has defined ‘‘negligible impact’’ in 50 CFR 216 as ‘‘* * * an impact resulting from the specified activity that cannot be reasonably expected to, and is not reasonably likely to, adversely affect the species or stock through effects on annual rates of recruitment or survival.’’ In making a negligible impact determination, NMFS considers a variety of factors, including but not limited to: (1) The number of anticipated mortalities; (2) the number and nature of anticipated injuries; (3) the number, nature, intensity, and duration of Level B harassment; and (4) the context in which the takes occur. Incidental take, in the form of Level B harassment only, is likely to occur primarily as a result of marine mammal exposure to elevated levels of sound resulting from the specified activities. No take by injury, serious injury, or death is anticipated or proposed for authorization. The expected impacts from this activity would be Level B VerDate Mar<15>2010 18:22 Sep 07, 2012 Jkt 226001 harassment in the form of behavioral disturbance resulting in, for example, changed direction or speed, or temporary avoidance of an area. Anticipated behavioral disturbance is likely to be of low intensity due to the sound source characteristics—the majority of activities considered here would produce low source levels of non-pulsed sound that would be either intermittent or transient—and relatively short in duration associated with the specified activities. For the same reasons, no individual marine mammals are expected to incur any hearing impairment, whether temporary or permanent in nature. That is, nonpulsed sound does not produce the rapid rise times that are more likely to produce hearing impairment in marine mammals, and the low intensity of the sources would result in Level A isopleths within a short distance. Several activities would produce source levels below those considered capable of causing hearing impairment, even in close proximity to marine mammals. The shutdown zone monitoring proposed as mitigation, and the small size of the zones in which injury may occur, further reduces the potential for any injury of marine mammals, making the possibility of hearing impairment extremely unlikely and therefore discountable. PO 00000 Frm 00030 Fmt 4701 Sfmt 4702 For the greater portion of the life of this proposed rule (i.e., 4 years remaining after the first year of construction), only port operations would occur. Each episode of SRV arrival/departure (requiring thruster use for a period of several hours) would be separated by approximately 8 days of regasification, an activity not expected to result in incidental take. The likely effects of behavioral disturbance from port operations are minor, as many animals perform vital functions, such as feeding, resting, traveling, and socializing, on a diel (24-hour) cycle. Behavioral reactions to sound exposure (such as disruption of critical life functions, displacement, or avoidance of important habitat) are more likely to be significant if they last more than one diel cycle or recur on subsequent days (Southall et al., 2007). Operational activities would occur on a single day (i.e., arrival or departure of a SRV), would not recur for a period of 8 days, and, as for the majority of construction activities, would produce only low levels of non-pulsed sound. NMFS’ current criterion for Level B harassment from non-pulsed, underwater sound levels (the vast majority of sound produced by the proposed activities) is 120 dB rms. However, not all marine mammals react to sounds at this low level, and many will not show strong reactions (and in some cases any E:\FR\FM\10SEP3.SGM 10SEP3 mstockstill on DSK4VPTVN1PROD with PROPOSALS3 Federal Register / Vol. 77, No. 175 / Monday, September 10, 2012 / Proposed Rules reaction) until sounds are much stronger. Neither the bottlenose dolphin nor spotted dolphin is listed under the ESA. However, NMFS considers the bay, sound, and estuarine stock of bottlenose dolphins (of which the Tampa Bay/ Sarasota Bay populations are a component) to be strategic under the MMPA. NMFS is in the process of writing individual stock assessment reports for each of the 32 bay, sound and estuary stocks of bottlenose dolphins, but none has been completed for the Tampa Bay/Sarasota Bay populations. There is insufficient data to determine population trends or status of the relevant stocks relative to optimum sustainable population. Population estimates for these species were provided earlier in this document (see the ‘‘Description of Marine Mammals in the Area of the Specified Activity’’ section). The maximum estimated take per year of Atlantic spotted dolphins (290) would be small relative to the stock size (37,611; 0.1 percent); this would decline for subsequent years of operations. As a result, only small numbers of Atlantic spotted dolphins would be taken. For bottlenose dolphins, the maximum estimated total take per year for all bottlenose dolphins (860) is small relative to the coastal stock size (7,702; 11 percent); this would decline for subsequent years of operations. As a result, only small numbers of bottlenose dolphins from the coastal stock could be taken. However, it is difficult to partition potential takings between the coastal stock (7,702) and the smaller bay, sound, and estuarine stock (719) because the possibility for mixing of the stocks precludes any quantitative understanding of how the total estimated taking might be apportioned between stocks. Although it is not possible to predict that portion of overall incidental take that might accrue to bay dolphin populations, NMFS believes that the potential effects of the proposed activities represent a negligible impact for bay dolphins. Only a subset of the specified activities has the potential to affect bay dolphins. Buoy installation and impact pile driving, as well as the entire offshore portion of pipelaying and burial, would occur offshore and would not have the potential to affect the bay dolphin populations. Vibratory pile driving would occur entirely within Tampa Bay, as would a portion of inshore pipelaying and burial, and could impact the bay populations. Vibratory pile driving would occur for only 8 days (at two piles per day), meaning that any harassment VerDate Mar<15>2010 18:22 Sep 07, 2012 Jkt 226001 experienced by bay dolphins from this activity would be of very short duration. In addition, Tampa Bay is significantly industrialized and urbanized and is heavily used by recreational boaters. Bottlenose dolphins occurring in Tampa Bay are somewhat acclimated to disturbance and would not be expected to experience significant disruption to behavioral patterns on the basis of shortterm and low intensity disturbance, such as is proposed for this project. The proposed activities would not take place in areas known to be of special significance for feeding or breeding. In summary, NMFS believes that potential impacts to bay dolphins represent a negligible impact for the following reasons: (1) Only a subset of project activities have the potential to affect bay dolphins; (2) any takes would be of low intensity (resulting from exposure to low levels of non-pulsed sound over a limited duration) and likely would not result in significant alteration of dolphin behavior in the heavily urbanized/industrialized area where the activity would occur; (3) any takes are likely to represent repeated takes of individuals using the area where the activity is occurring, rather than each take being of a new individual; and (4) an unknown, but possibly large, number of coastal stock dolphins may be mixing in inshore waters at any given time, and it is not possible to accurately determine how many of the takes may occur to individuals of the coastal stock versus individuals of the bay stock. Finally, following the initial year of construction, all operations would occur offshore, and there would be no potential for incidental take of bay dolphins. Based on the analysis contained herein of the likely effects of the specified activity on marine mammals and their habitat, and taking into consideration the implementation of the mitigation and monitoring measures, NMFS preliminarily finds that construction and operation of Port Dolphin would result in the incidental take of small numbers of marine mammals, by Level B harassment only, and that the total taking from Port Dolphin’s proposed activities would have a negligible impact on the affected species or stocks. Impact on Availability of Affected Species or Stock for Taking for Subsistence Uses There are no relevant subsistence uses of marine mammals implicated by this action. PO 00000 Frm 00031 Fmt 4701 Sfmt 4702 55675 Endangered Species Act (ESA) On August 4, 2009, NMFS concluded consultation with MarAd and USCG under section 7 of the ESA on the proposed construction and operation of the Port Dolphin LNG facility. The result of that consultation was NMFS’ concurrence with Port Dolphin’s determination that the proposed activities may affect, but are not likely to adversely affect, listed species under NMFS’ jurisdiction. NMFS does not propose to authorize incidental take of any ESA-listed marine mammal species. No listed species will be impacted by the specified activities. National Environmental Policy Act (NEPA) The USCG and the MarAd initiated the public scoping process in July 2007, with the publication of a Notice of Intent (NOI) to prepare an Environmental Impact Statement (EIS) in the Federal Register. The NOI included information on public meetings and informational open houses; requested public comments on the scope of the EIS; and provided information on how the public could submit comments. A Notice of Availability for the Draft EIS was published in the Federal Register in April 2008. Subsequently, a final EIS was published in July 2009. MarAd issued a Record of Decision (ROD) approving, with conditions, the Port Dolphin Energy Deepwater Port License application on October 26, 2009. Because NMFS was a cooperating agency in the development of the Port Dolphin EIS, NMFS will adopt the EIS and, if appropriate, issue its own ROD for issuance of authorizations pursuant to section 101(a)(5)(A) of the MMPA for the activities proposed by Port Dolphin. Information Solicited NMFS requests interested persons to submit comments, information, and suggestions concerning the request and the content of the proposed regulations to authorize the taking (see ADDRESSES). Classification The Office of Management and Budget (OMB) has determined that this proposed rule is not significant for purposes of Executive Order 12866. Pursuant to section 605(b) of the Regulatory Flexibility Act (RFA), the Chief Counsel for Regulation of the Department of Commerce has certified to the Chief Counsel for Advocacy of the Small Business Administration that this proposed rule, if adopted, would not have a significant economic impact on a substantial number of small entities. Port Dolphin Energy LLC is the only E:\FR\FM\10SEP3.SGM 10SEP3 55676 Federal Register / Vol. 77, No. 175 / Monday, September 10, 2012 / Proposed Rules entity that would be subject to the requirements in these proposed regulations. Port Dolphin is ultimately owned by the Norway-based shipping ¨ company Hoegh LNG AS, which is itself ¨ held by Leif Hoegh & Co, a global shipping company. Therefore, it is not a small governmental jurisdiction, small organization, or small business, as defined by the RFA. Because of this certification, a regulatory flexibility analysis is not required, and none has been prepared. Notwithstanding any other provision of law, no person is required to respond to nor shall a person be subject to a penalty for failure to comply with a collection of information subject to the requirements of the Paperwork Reduction Act (PRA) unless that collection of information displays a currently valid OMB control number. This proposed rule contains collectionof-information requirements subject to the provisions of the PRA. These requirements have been approved by OMB under control number 0648–0151 and include applications for regulations, subsequent LOAs, and reports. Send comments regarding any aspect of this data collection, including suggestions for reducing the burden, to NMFS and the OMB Desk Officer (see ADDRESSES). List of Subjects in 50 CFR Part 217 Exports, Fish, Imports, Indians, Labeling, Marine mammals, Penalties, Reporting and recordkeeping requirements, Seafood, Transportation. Dated: September 4, 2012. Alan D. Risenhoover, Director, Office of Sustainable Fisheries, performing the functions and duties of the Deputy Assistant Administrator for Regulatory Programs, National Marine Fisheries Service. For reasons set forth in the preamble, 50 CFR part 217 is proposed to be amended as follows: PART 217—REGULATIONS GOVERNING THE TAKE OF MARINE MAMMALS INCIDENTAL TO SPECIFIED ACTIVITIES 1. The authority citation for part 217 continues to read as follows: mstockstill on DSK4VPTVN1PROD with PROPOSALS3 Authority: 16 U.S.C. 1361 et seq. Subpart P—Taking Marine Mammals Incidental to Construction and Operation of a Liquefied Natural Gas Deepwater Port in the Gulf of Mexico Sec. 217.151 Specified activity and specified geographical region. 217.152 Effective dates. 18:22 Sep 07, 2012 Jkt 226001 Subpart P—Taking Marine Mammals Incidental to Construction and Operation of a Liquefied Natural Gas Deepwater Port in the Gulf of Mexico § 217.151 Specified activity and specified geographical region. (a) Regulations in this subpart apply only to Port Dolphin Energy LLC (Port Dolphin) and those persons it authorizes to conduct activities on its behalf for the taking of marine mammals that occurs in the area outlined in paragraph (b) of this section and that occur incidental to construction and operation of the Port Dolphin Deepwater Port (Port). (b) The taking of marine mammals by Port Dolphin may be authorized in a Letter of Authorization (LOA) only if it occurs in the vicinity of the Port Dolphin Deepwater Port in the eastern Gulf of Mexico or along the associated pipeline route. § 217.152 Effective dates. [Reserved] § 217.153 Permissible methods of taking. (a) Under LOAs issued pursuant to § 216.106 and § 217.157 of this chapter, the Holder of the LOA (hereinafter ‘‘Port Dolphin’’) may incidentally, but not intentionally, take marine mammals within the area described in § 217.151(b) of this chapter, provided the activity is in compliance with all terms, conditions, and requirements of the regulations in this subpart and the appropriate LOA. (b) The incidental take of marine mammals under the activities identified in § 217.151(a) of this chapter is limited to the following species and is limited to Level B Harassment: (1) Bottlenose dolphin (Tursiops truncatus)—3,388 (860 the first year and an average of 632 annually thereafter) (2) Atlantic spotted dolphin (Stenella frontalis)—1,274 (290 the first year and an average of 246 annually thereafter) § 217.154 2. Subpart P is added to part 217 to read as follows: VerDate Mar<15>2010 217.153 Permissible methods of taking. 217.154 Prohibitions. 217.155 Mitigation. 217.156 Requirements for monitoring and reporting. 217.157 Letters of Authorization. 217.158 Renewals and Modifications of Letters of Authorization. Prohibitions. Notwithstanding takings contemplated in § 217.151 of this chapter and authorized by a LOA issued under § 216.106 and § 217.157 of this chapter, no person in connection with the activities described in § 217.151 of this chapter may: (a) Take any marine mammal not specified in § 217.153(b) of this chapter; PO 00000 Frm 00032 Fmt 4701 Sfmt 4702 (b) Take any marine mammal specified in § 217.153(b) of this chapter other than by incidental, unintentional Level B Harassment; (c) Take a marine mammal specified in § 217.153(b) of this chapter if such taking results in more than a negligible impact on the species or stocks of such marine mammal; or (d) Violate, or fail to comply with, the terms, conditions, and requirements of this subpart or a LOA issued under § 216.106 and § 217.157 of this chapter. § 217.155 Mitigation. (a) When conducting the activities identified in § 217.151(a) of this chapter, the mitigation measures contained in any LOA issued under § 216.106 and § 217.157 of this chapter must be implemented. These mitigation measures include but are not limited to: (1) General Conditions: (i) Briefings shall be conducted between the Port Dolphin project construction supervisors and the crew, protected species observer(s) (PSO), and acoustic monitoring team prior to the start of all construction activity, and when new personnel join the work, to explain responsibilities, communication procedures, protected species monitoring protocol, and operational procedures. (ii) Port Dolphin shall comply with all applicable equipment sound standards and ensure that all construction equipment has sound control devices no less effective than those provided on the original equipment. Vessel crew and contractors shall minimize the production of underwater sound to the extent possible. Equipment and/or procedures used may include the use of enclosures and mufflers on equipment, minimizing the use of thrusters, and turning off engines and equipment when not in use. (iii) All vessels associated with Port Dolphin construction and operations shall comply with NMFS Vessel Strike Avoidance Measures and Reporting for Mariners and applicable regulations. All vessels associated with Port Dolphin construction and operations shall remain 500 yd (457 m) away from North Atlantic right whales (Eubalaena glacialis) and 100 yd (91 m) away from all other marine mammals, except in cases where small marine mammals (i.e., delphinids) voluntarily approach within 100 yd or unless constrained by human safety concerns or navigational constraints. (2) Shutdown and Monitoring: (i) Shutdown zone: For all activities, shutdown zones shall be established. These zones shall include all areas where underwater sound pressure levels E:\FR\FM\10SEP3.SGM 10SEP3 mstockstill on DSK4VPTVN1PROD with PROPOSALS3 Federal Register / Vol. 77, No. 175 / Monday, September 10, 2012 / Proposed Rules (SPLs) are anticipated to equal or exceed 180 dB re: 1 mPa rms, as determined by modeled scenarios approved by NMFS for each specific activity. The actual size of these zones shall be empirically determined and reported by Port Dolphin. For all non-stationary activities (e.g., pipeline burial, shuttle regasification vessel (SRV) maneuvering), Port Dolphin shall maintain a minimum 100 yd (91 m) distance from marine mammals, with the exception that voluntary approach (e.g., bow riding) within the 100 yd zone by delphinids shall not trigger shutdown requirements. (ii) Disturbance zone: For all activities, disturbance zones shall be established. For impact pile driving, these zones shall include all areas where underwater SPLs are anticipated to equal or exceed 160 dB re: 1 mPa rms. For all other activities these zones shall include all areas where underwater SPLs are anticipated to equal or exceed 120 dB re: 1 mPa rms. These zones shall be established on the basis of modeled scenarios approved by NMFS for each specific activity. The actual size of disturbance zones shall be empirically determined and reported by Port Dolphin, and on-site PSOs shall be aware of the size of these zones. However, because of the large size of these zones, monitoring of the zone is required only to maximum line-of-sight distance from established monitoring locations. (iii) Monitoring of shutdown and disturbance zones shall occur for all activities. The following measures shall apply: (A) Shutdown and disturbance zones shall be monitored from the appropriate vessel or work platform, or other suitable vantage point. Port Dolphin shall at all times employ, at minimum, two PSOs in association with each concurrent specified construction activity. (B) The shutdown zone shall be monitored for the presence of marine mammals before, during, and after construction activity. For all activities, the shutdown zone shall be monitored for 30 minutes prior to initiating the start of activity and for 30 minutes following the completion of activity. If marine mammals are present within the shutdown zone prior to initiating activity, the start shall be delayed until the animals leave the shutdown zone of their own volition or until 15 minutes has elapsed without observing the animal. If a marine mammal is observed within or approaching the shutdown zone, activity shall be halted as soon as it is safe to do so, until the animal is observed exiting the shutdown zone or VerDate Mar<15>2010 18:22 Sep 07, 2012 Jkt 226001 15 minutes has elapsed. If a marine mammal is observed within the disturbance zone, a take shall be recorded and behaviors documented. (C) PSOs shall be on watch at all times during daylight hours when in-water operations are being conducted, unless conditions (e.g., fog, rain, darkness) make observations impossible. If conditions deteriorate during daylight hours such that the sea surface observations are halted, visual observations must resume as soon as conditions permit. While activities will be permitted to continue during lowvisibility conditions, they (1) must have been initiated following proper clearance of the shutdown zone under acceptable observation conditions; and (2) must be restarted, if halted for any reason, using the appropriate shutdown zone clearance procedures as described in § 217.155(a)(2)(iii)(B) of this chapter. (3) Pile driving: (i) A minimum shutdown zone of 250 m radius shall be established around all impact pile driving activity. (ii) Contractors shall reduce the power of impact hammers to minimum energy levels required to drive a pile. (iii) Port Dolphin shall use a sound attenuation measure for impact driving of pilings. Prior to beginning construction, Port Dolphin must provide information to NMFS about the device to be used, including technical specifications. NMFS must approve use of the device before construction may begin. If a bubble curtain or similar measure is used, it shall distribute small air bubbles around 100 percent of the piling perimeter for the full depth of the water column. Any other attenuation measure (e.g., temporary sound attenuation pile) must provide 100 percent coverage in the water column for the full depth of the pile. Prior to any impact pile driving, a performance test of the sound attenuation device must be conducted in accordance with a NMFS-approved acoustic monitoring plan. If a bubble curtain or similar measure is utilized, the performance test shall confirm the calculated pressures and flow rates at each manifold ring. (iv) Ramp-up: (A) A ramp-up technique shall be used at the beginning of each day’s inwater pile driving activities and if pile driving resumes after it has ceased for more than 1 hour. (B) If a vibratory driver is used, contractors shall be required to initiate sound from vibratory hammers for 15 seconds at reduced energy followed by a 1-minute waiting period. The procedure shall be repeated two additional times before full energy may be achieved. PO 00000 Frm 00033 Fmt 4701 Sfmt 4702 55677 (C) If a non-diesel impact hammer is used, contractors shall be required to provide an initial set of strikes from the impact hammer at reduced energy, followed by a 1-minute waiting period, then two subsequent sets. (D) If a diesel impact hammer is used, contractors shall be required to turn on the sound attenuation device for 15 seconds prior to initiating pile driving. (v) No impact pile driving shall occur when visibility in the shutdown zone is significantly limited, such as during heavy rain or fog. (4) Additional mitigation measures: (i) Use of lights during construction activities shall be limited to areas where work is actually occurring, and all other lights must be extinguished. Lights must be shielded such that they illuminate the deck and do not intentionally illuminate surrounding waters, to the extent possible. (ii) Additional mitigation measures as contained in a LOA issued under § 216.106 and § 217.157 of this chapter. (b) [Reserved] § 217.156 Requirements for monitoring and reporting. (a) Visual monitoring program: (1) Port Dolphin shall employ, at minimum, two qualified PSOs during specified construction-related activities at each site where such activities are occurring. All PSOs must be selected in conformance with NMFS’ minimum qualifications, as described in the preamble to this rule, and must receive training sponsored by Port Dolphin, with topics to include, at minimum, implementation of the monitoring protocol, identification of marine mammals, and reporting requirements. The PSOs shall be responsible for visually locating marine mammals in the shutdown and disturbance zones and, to the extent possible, identifying the species. PSOs shall record, at minimum, the following information: (i) A count of all marine mammals observed by species, sex, and age class, when possible. (ii) Their location within the shutdown or disturbance zone, and their reaction (if any) to construction activities, including direction of movement. (iii) Activity that is occurring at the time of observation, including time that activity begins and ends, any acoustic or visual disturbance, and time of the observation. (iv) Environmental conditions, including wind speed, wind direction, visibility, and temperature. (2) Port Dolphin shall sponsor a training course to designated crew members assigned to vessels associated E:\FR\FM\10SEP3.SGM 10SEP3 mstockstill on DSK4VPTVN1PROD with PROPOSALS3 55678 Federal Register / Vol. 77, No. 175 / Monday, September 10, 2012 / Proposed Rules with construction activities or support of operations who will have responsibilities for watching for marine mammals. This course shall cover topics including, but not limited to, descriptions of the marine mammals found in the area, mitigation and monitoring requirements contained in a LOA, sighting log requirements, provisions of NMFS Vessel Strike Avoidance Measures and Reporting for Mariners, and procedures for reporting injured or dead marine mammals. (3) Monitoring shall be conducted using appropriate binoculars, such as 8x50 marine binoculars. When possible, digital video or still cameras shall also be used to document the behavior and response of marine mammals to construction activities or other disturbances. (4) Each PSO shall have two-way communication capability for contact with other PSOs or work crews. PSOs shall implement shut-down or delay procedures when applicable by calling for the shut-down to the equipment/ vessel operator. (5) A GPS unit and/or appropriate range finding device shall be used for determining the observation location and distance to marine mammals, vessels, and construction equipment. (6) During arrival and departure of SRVs and regasification, qualified PSOs may not be required. During SRV arrival and departure, while thrusters are engaged for maneuvering, an additional lookout shall be designated to exclusively and continuously monitor for marine mammals. All sightings of marine mammals by the designated lookout, individuals posted to navigational lookout duties, or any other crew member while the SRV is maneuvering or in transit to or from the Port shall be immediately reported to the watch officer who shall then alert the Master. The SRV must report to Port Dolphin any observations of marine mammals while maneuvering with thrusters. (b) Acoustic monitoring program: (1) Port Dolphin must provide NMFS with an acoustic monitoring plan describing the planned measurement of underwater sound pressure levels from designated construction and operation activities as well as the characterization of site-specific sound propagation. NMFS must approve this plan before activities may begin, and acoustic monitoring must be conducted in accordance with the plan. (2) Port Dolphin shall provide NMFS with empirically measured source level data for designated sources of sound associated with Port construction and operation activities and shall verify VerDate Mar<15>2010 18:22 Sep 07, 2012 Jkt 226001 distances to relevant sound thresholds. Measurements shall be carefully coordinated with sound-producing activities. (3) [Reserved] (c) Reporting—Port Dolphin must implement the following reporting requirements: (1) A report of data collected during monitoring shall be submitted to NMFS following conclusion of construction activities. Subsequent reports concerning Port operations shall be submitted annually. The reports shall include: (i) All data required to be collected during monitoring, as described under 217.156(a) of this chapter, including observation dates, times, and conditions; (ii) Correlations of observed behavior with activity type and received levels of sound, to the extent possible; and (iii) Estimations of total incidental take of marine mammals, extrapolated from observed incidental take. (2) Port Dolphin shall also submit a report(s) concerning the results of all acoustic monitoring. Acoustic monitoring reports shall include information as described in a NMFSapproved acoustic monitoring plan. (3) Reporting injured or dead marine mammals: (i) In the unanticipated event that the specified activity clearly causes the take of a marine mammal in a manner prohibited by a LOA (if issued), such as an injury (Level A harassment), serious injury, or mortality, Port Dolphin shall immediately cease the specified activities and report the incident to the Chief of the Permits and Conservation Division, Office of Protected Resources, NMFS, and the Southeast Regional Stranding Coordinator, NMFS. The report must include the following information: (A) Time and date of the incident; (B) Description of the incident; (C) Environmental conditions (e.g., wind speed and direction, Beaufort sea state, cloud cover, and visibility); (D) Description of all marine mammal observations in the 24 hours preceding the incident; (E) Species identification or description of the animal(s) involved; (F) Fate of the animal(s); and (G) Photographs or video footage of the animal(s). Activities shall not resume until NMFS is able to review the circumstances of the prohibited take. NMFS will work with Port Dolphin to determine what measures are necessary to minimize the likelihood of further prohibited take and ensure MMPA compliance. Port Dolphin may not PO 00000 Frm 00034 Fmt 4701 Sfmt 4702 resume their activities until notified by NMFS. (ii) In the event that Port Dolphin discovers an injured or dead marine mammal, and the lead PSO determines that the cause of the injury or death is unknown and the death is relatively recent (e.g., in less than a moderate state of decomposition), Port Dolphin shall immediately report the incident to the Chief of the Permits and Conservation Division, Office of Protected Resources, NMFS, and the Southeast Regional Stranding Coordinator, NMFS. The report must include the same information identified in 217.156(b)(3)(i) of this chapter. Activities may continue while NMFS reviews the circumstances of the incident. NMFS will work with Port Dolphin to determine whether additional mitigation measures or modifications to the activities are appropriate. (iii) In the event that Port Dolphin discovers an injured or dead marine mammal, and the lead PSO determines that the injury or death is not associated with or related to the activities authorized in the LOA (e.g., previously wounded animal, carcass with moderate to advanced decomposition, or scavenger damage), Port Dolphin shall report the incident to the Chief of the Permits and Conservation Division, Office of Protected Resources, NMFS, and the Southeast Regional Stranding Coordinator, NMFS, within 24 hours of the discovery. Port Dolphin shall provide photographs or video footage or other documentation of the stranded animal sighting to NMFS. (4) Annual Reports. (i) A report summarizing all marine mammal monitoring and construction activities shall be submitted to NMFS, Office of Protected Resources, and NMFS, Southeast Regional Office (specific contact information to be provided in LOA) following the conclusion of construction activities. Thereafter, Port Dolphin shall submit annual reports summarizing marine mammal monitoring and operations activities. (ii) The annual reports shall include data collected for each distinct marine mammal species observed in the project area. Description of marine mammal behavior, overall numbers of individuals observed, frequency of observation, and any behavioral changes and the context of the changes relative to activities shall also be included in the reports. Additional information that shall be recorded during activities and contained in the reports include: Date and time of marine mammal detections, weather conditions, species E:\FR\FM\10SEP3.SGM 10SEP3 Federal Register / Vol. 77, No. 175 / Monday, September 10, 2012 / Proposed Rules identification, approximate distance from the source, and activity at the construction site when a marine mammal is sighted. (5) Five-year Comprehensive Report. (i) Port Dolphin shall submit a draft comprehensive final report to NMFS, Office of Protected Resources, and NMFS, Southeast Regional Office (specific contact information to be provided in LOA) 180 days prior to the expiration of the regulations. This comprehensive technical report shall provide full documentation of methods, results, and interpretation of all monitoring during the first 4.5 years of the activities conducted under the regulations in this Subpart. (ii) Port Dolphin shall submit a revised final comprehensive technical report, including all monitoring results during the entire period of the LOAs, 90 days after the end of the period of effectiveness of the regulations to NMFS, Office of Protected Resources, and NMFS, Southeast Regional Office (specific contact information to be provided in LOA). § 217.157 Letters of Authorization. mstockstill on DSK4VPTVN1PROD with PROPOSALS3 (a) To incidentally take marine mammals pursuant to these regulations, Port Dolphin must apply for and obtain a LOA. (b) A LOA, unless suspended or revoked, may be effective for a period of time not to exceed the expiration date of these regulations. (c) If an LOA expires prior to the expiration date of these regulations, Port Dolphin must apply for and obtain a renewal of the LOA. (d) In the event of projected changes to the activity or to mitigation and monitoring measures required by an LOA, Port Dolphin must apply for and obtain a modification of the LOA as described in § 217.158 of this chapter. (e) The LOA shall set forth: (1) Permissible methods of incidental taking; VerDate Mar<15>2010 18:22 Sep 07, 2012 Jkt 226001 (2) Means of effecting the least practicable adverse impact (i.e., mitigation) on the species, its habitat, and on the availability of the species for subsistence uses; and (3) Requirements for monitoring and reporting. (f) Issuance of the LOA shall be based on a determination that the level of taking will be consistent with the findings made for the total taking allowable under these regulations. (g) Notice of issuance or denial of a LOA shall be published in the Federal Register within 30 days of a determination. § 217.158 Renewals and modifications of Letters of Authorization. (a) A LOA issued under § 216.106 and § 217.157 of this chapter for the activity identified in § 217.151(a) of this chapter shall be renewed or modified upon request by the applicant, provided that: (1) The proposed specified activity and mitigation, monitoring, and reporting measures, as well as the anticipated impacts, are the same as those described and analyzed for these regulations (excluding changes made pursuant to the adaptive management provision in § 217.158(c)(1) of this chapter), and (2) NMFS determines that the mitigation, monitoring, and reporting measures required by the previous LOA under these regulations were implemented. (b) For LOA modification or renewal requests by the applicant that include changes to the activity or the mitigation, monitoring, or reporting (excluding changes made pursuant to the adaptive management provision in § 217.158(c)(1) of this chapter) that do not change the findings made for the regulations or result in no more than a minor change in the total estimated number of takes (or distribution by species or years), NMFS may publish a notice of proposed LOA in the Federal Register, including the associated PO 00000 Frm 00035 Fmt 4701 Sfmt 9990 55679 analysis of the change, and solicit public comment before issuing the LOA. (c) A LOA issued under § 216.106 and § 217.157 of this chapter for the activity identified in § 217.151(a) of this chapter may be modified by NMFS under the following circumstances: (1) Adaptive Management—NMFS may modify (including augment) the existing mitigation, monitoring, or reporting measures (after consulting with Port Dolphin regarding the practicability of the modifications) if doing so creates a reasonable likelihood of more effectively accomplishing the goals of the mitigation and monitoring set forth in the preamble for these regulations. (i) Possible sources of data that could contribute to the decision to modify the mitigation, monitoring, or reporting measures in an LOA: (A) Results from Port Dolphin’s monitoring from the previous year(s). (B) Results from other marine mammal and/or sound research or studies. (C) Any information that reveals marine mammals may have been taken in a manner, extent or number not authorized by these regulations or subsequent LOAs. (ii) If, through adaptive management, the modifications to the mitigation, monitoring, or reporting measures are substantial, NMFS will publish a notice of proposed LOA in the Federal Register and solicit public comment. (2) Emergencies—If NMFS determines that an emergency exists that poses a significant risk to the well-being of the species or stocks of marine mammals specified in § 217.153(b) of this chapter, an LOA may be modified without prior notice or opportunity for public comment. Notice would be published in the Federal Register within 30 days of the action. [FR Doc. 2012–22092 Filed 9–7–12; 8:45 am] BILLING CODE 3510–22–P E:\FR\FM\10SEP3.SGM 10SEP3

Agencies

[Federal Register Volume 77, Number 175 (Monday, September 10, 2012)]
[Proposed Rules]
[Pages 55645-55679]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2012-22092]



[[Page 55645]]

Vol. 77

Monday,

No. 175

September 10, 2012

Part IV





Department of Commerce





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National Oceanic and Atmospheric Administration





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50 CFR Part 217





Taking and Importing Marine Mammals; Taking Marine Mammals Incidental 
to Construction and Operation of a Liquefied Natural Gas Deepwater Port 
in the Gulf of Mexico; Proposed Rule

Federal Register / Vol. 77 , No. 175 / Monday, September 10, 2012 / 
Proposed Rules

[[Page 55646]]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

50 CFR Part 217

[Docket No. 110801452-2387-03]
RIN 0648-BB00


Taking and Importing Marine Mammals; Taking Marine Mammals 
Incidental to Construction and Operation of a Liquefied Natural Gas 
Deepwater Port in the Gulf of Mexico

AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and 
Atmospheric Administration (NOAA), Commerce.

ACTION: Proposed rule; request for comments.

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SUMMARY: NMFS has received a request from Port Dolphin Energy LLC (Port 
Dolphin) for authorization to take marine mammals incidental to port 
construction and operations at its Port Dolphin Deepwater Port in the 
Gulf of Mexico, over the course of five years; approximately June 2013 
through May 2018. Pursuant to the Marine Mammal Protection Act (MMPA), 
NMFS is proposing regulations to govern that take and requests 
information, suggestions, and comments on these proposed regulations.

DATES: Comments and information must be received no later than October 
25, 2012.

ADDRESSES: You may submit comments on this document, identified by FDMS 
Docket Number 110801452-2387-03, by any of the following methods:
     Electronic Submission: Submit all electronic public 
comments via the Federal e-Rulemaking Portal www.regulations.gov. To 
submit comments via the e-Rulemaking Portal, first click the Submit a 
Comment icon, and then enter 110801452-2387-03 in the keyword search. 
Locate the document you wish to comment on from the resulting list and 
click on the Submit a Comment icon on the right of that line.
     Hand delivery or mailing of comments via paper or disc 
should be addressed to Michael Payne, Chief, Permits and Conservation 
Division, Office of Protected Resources, National Marine Fisheries 
Service, 1315 East-West Highway, Silver Spring, MD 20910.
    Comments regarding any aspect of the collection of information 
requirement contained in this proposed rule should be sent to NMFS via 
one of the means provided here and to the Office of Information and 
Regulatory Affairs, NEOB-10202, Office of Management and Budget, Attn: 
Desk Office, Washington, DC 20503, OIRA@omb.eop.gov.
    Instructions: Comments must be submitted by one of the above 
methods to ensure that the comments are received, documented, and 
considered by NMFS. Comments sent by any other method, to any other 
address or individual, or received after the end of the comment period, 
may not be considered. All comments received are a part of the public 
record and will generally be posted for public viewing on 
www.regulations.gov without change. All personal identifying 
information (e.g., name, address) submitted voluntarily by the sender 
will be publicly accessible. Do not submit confidential business 
information, or otherwise sensitive or protected information. NMFS will 
accept anonymous comments (enter N/A in the required fields if you wish 
to remain anonymous). Attachments to electronic comments will be 
accepted in Microsoft Word, Excel, or Adobe PDF file formats only.

FOR FURTHER INFORMATION CONTACT: Ben Laws, Office of Protected 
Resources, NMFS, (301) 427-8401.

SUPPLEMENTARY INFORMATION:

Availability

    A copy of Port Dolphin's application may be obtained by writing to 
the address specified above (see ADDRESSES), calling the contact listed 
above (see FOR FURTHER INFORMATION CONTACT), or visiting the Internet 
at: http://www.nmfs.noaa.gov/pr/permits/incidental.htm. To help NMFS 
process and review comments more efficiently, please use only one 
method to submit comments.

Background

    Sections 101(a)(5)(A) and (D) of the MMPA (16 U.S.C. 1361 et seq.) 
direct the Secretary of Commerce to allow, upon request, the 
incidental, but not intentional, taking of small numbers of marine 
mammals by U.S. citizens who engage in a specified activity (other than 
commercial fishing) within a specified geographical region if certain 
findings are made and either regulations are issued or, if the taking 
is limited to harassment, a notice of a proposed authorization is 
provided to the public for review.
    Authorization for incidental takings shall be granted if NMFS finds 
that the taking will have a negligible impact on the species or 
stock(s), will not have an unmitigable adverse impact on the 
availability of the species or stock(s) for subsistence uses (where 
relevant), and if the permissible methods of taking and requirements 
pertaining to the mitigation, monitoring and reporting of such takings 
are set forth. NMFS has defined ``negligible impact'' in 50 CFR 216.103 
as ``* * * an impact resulting from the specified activity that cannot 
be reasonably expected to, and is not reasonably likely to, adversely 
affect the species or stock through effects on annual rates of 
recruitment or survival.''
    Except with respect to certain activities not pertinent here, the 
MMPA defines ``harassment'' as: ``any act of pursuit, torment, or 
annoyance which (i) has the potential to injure a marine mammal or 
marine mammal stock in the wild [`Level A harassment']; or (ii) has the 
potential to disturb a marine mammal or marine mammal stock in the wild 
by causing disruption of behavioral patterns, including, but not 
limited to, migration, breathing, nursing, breeding, feeding, or 
sheltering [`Level B harassment'].''

Summary of Request

    On February 1, 2011, NMFS received a complete application from Port 
Dolphin for the taking of marine mammals incidental to port 
construction and operations at its Port Dolphin Deepwater Port (DWP) 
facility in the Gulf of Mexico (GOM). During the period of these 
proposed regulations (June 2013-May 2018), Port Dolphin proposes to 
construct the DWP and related infrastructure--expected to occur over an 
approximately 11-month period, beginning in June 2013--and to 
subsequently begin operations. The proposed DWP, which is designed to 
have an operational life expectancy of 25 years, would be an offshore 
liquefied natural gas (LNG) facility, located in the GOM approximately 
45 km (28 mi) off the western coast of Florida, and approximately 68 km 
(42 mi) from Port Manatee, located in Manatee County, Florida, within 
Tampa Bay (see Figure S-1 in Port Dolphin's application). The DWP would 
be in waters of the U.S. Exclusive Economic Zone (EEZ) approximately 31 
m (100 ft) in depth. The proposed DWP would consist principally of a 
permanently moored buoy system, designed for offloading of natural gas, 
leading to a single proposed new natural gas transmission pipeline that 
would come ashore at Port Manatee and connect to existing 
infrastructure.
    Take of marine mammals would occur as a result of the introduction 
of sound into the marine environment during construction of the DWP and 
pipeline and during DWP operations, which would involve shuttle 
regasification

[[Page 55647]]

vessel (SRV) maneuvering, docking, and debarkation, as well as 
regasification activity. Because the specified activities have the 
potential to take marine mammals present within the action area, Port 
Dolphin requests authorization to incidentally take, by Level B 
harassment only, small numbers of bottlenose dolphin (Tursiops 
truncatus) and Atlantic spotted dolphin (Stenella frontalis).

Description of the Specified Activity

    Port Dolphin proposes to own, construct, and operate a DWP in the 
U.S. EEZ of the GOM Outer Continental Shelf (OCS) approximately 45 km 
(28 mi) off the western coast of Florida to the southwest of Tampa Bay, 
in a water depth of approximately 31 m (100 ft). On March 29, 2007, 
Port Dolphin submitted an application to the U.S. Coast Guard (USCG) 
and the U.S. Maritime Administration (MarAd) for all federal 
authorizations required for a DWP license under the Deepwater Port Act 
of 1974 (DWPA). Port Dolphin received that license in October 2009. The 
Port would consist of a permanently moored unloading buoy system with 
two submersible buoys separated by a distance of approximately 5 km (3 
mi). The buoys would be designed to moor a specialized type of LNG 
carrier vessel (i.e., SRVs) and would remain submerged when vessels are 
not present. Regasified natural gas would be sent out through the 
unloading buoy to a 36-in (0.9 m) pipeline that would connect onshore 
at Port Manatee with the existing Gulfstream Natural Gas System and 
Tampa Electric Company (TECO) Bayside pipeline. The DWP would only 
serve SRVs. Construction of the DWP would be expected to take 11 
months. Port Dolphin DWP would be designed, constructed, and operated 
in accordance with applicable codes and standards and would have an 
expected operating life of approximately 25 years. The locations of the 
DWP and associated pipeline are shown in Figure S-1 in Port Dolphin's 
application; Figure 1-1 of the same document depicts a conceptual site 
plan for the DWP.
    The installation of the DWP facilities would include the 
construction and installation of offshore buoys, mooring lines, and 
anchors. The two unloading buoys, also known as submerged turret 
loading (STL) buoys, would each have eight mooring lines connected to 
anchor points, likely consisting of piles driven into the seabed. When 
not connected to a SRV, STL buoys would be submerged 60 to 70 ft (18 to 
21 m) below the sea surface. The installation of the pipeline from the 
DWP to shore would include burial of the pipeline, selective placement 
of protective cover (either rock armoring or concrete mattresses) over 
the pipeline at several locations along the pipeline route where full 
burial is not possible, and the horizontal directional drilling (HDD) 
of three segments of the pipeline.
    SRVs are specialized LNG carriers designed to regasify the LNG 
prior to off-loading for transport to shore. Each STL buoy would moor 
one SRV on location throughout the unloading cycle. An SRV would 
typically moor at the deepwater port for between 4 and 8 days, 
depending on vessel size and send-out rate. Unloading of natural gas 
(i.e., vaporization or regasification) would occur through a flexible 
riser connected to the STL buoy and into the pipeline end manifold 
(PLEM) for transportation to shore via the subsea pipeline. With two 
separate STL buoys, Port Dolphin may schedule an overlap between 
arriving and departing SRVs, thus allowing natural gas to be delivered 
in a continuous flow.
    Port Dolphin is planning for an initial natural gas throughput of 
400 million standard cubic feet per day (MMscfd). Although the Port 
would be capable of an average of 800 MMscfd with a peak capacity of 
1,200 MMscfd, this level of throughput would not be achieved during the 
span of this proposed rule. Based on a regasification cycle of 
approximately 8 days and initial throughput of 400 MMscfd, maximum 
vessel traffic during operations over the lifetime of the proposed 5-
year regulations is projected to consist of 46 SRV unloadings per year.
    In the open ocean, SRVs typically travel at speeds of up to 19.5 kn 
(36.1 km/hr). When approaching the vicinity of the DWP (i.e., during 
approach to the DWP), the SRVs would typically slow to about half 
speed. In close proximity to the STL buoys, the SRVs would slow to dead 
slow and utilize thrusters to attain proper vessel orientation relative 
to the DWP, taking into consideration ambient ocean currents, wind 
conditions, and buoy position. The following subsections describe the 
Region of Activity and the preceding facets of construction and 
operation in greater detail.

Region of Activity

    The GOM is a marine water body bounded by Cuba on the southeast; 
Mexico on the south and southwest; and the U.S. Gulf Coast on the west, 
north, and east. The GOM has a total area of 564,000 km\2\ (217,762 
mi\2\). Shallow and intertidal areas (water depths of less than 20 m) 
compose 38 percent of the total area, with continental shelf (22 
percent), continental slope (20 percent), and abyssal plain (20 
percent) composing the remainder of the basin. The project site is 
located on the west Florida Shelf, a portion of the Inner Continental 
Shelf, in an area of relatively low wave energy and tidal variation 
(Gore, 1992).
    The GOM is separated from the Caribbean Sea and Atlantic Ocean by 
Cuba and other islands, and has relatively narrow connections to the 
Caribbean and Atlantic through the Florida and Yucatan Straits. The GOM 
is composed of three distinct water masses, including the North and 
South Atlantic Surface Water (less than 100 m deep), Atlantic and 
Caribbean Subtropical Water (up to 500 m deep), and Subantarctic 
Intermediate Water.
    Circulation within the GOM, and within the project area, is 
dominated by the Loop Current, which enters the GOM flowing north 
through the Yucatan Strait, flows south along the Florida coast in the 
vicinity of the project area, and exits the GOM through the Florida 
Straits. The velocity of the current in the project area ranges between 
1.56 and 15.16 cm/s in summer, and 1.79 to 25.36 cm/s in winter (APL, 
2006). The direction of flow in the project area is generally south to 
southeast.
    In shallow areas along the west Florida Shelf, additional 
influences on water flow and circulation include wind stress, 
freshwater inflow, and variations in buoyancy (Gore, 1992). Wind speeds 
at the project site range from 2.26 to 7.61 m/s in summer, and 2.85 to 
11.04 m/s in winter (APL, 2006). Tidal variation along Florida's west-
central continental shelf is moderate, with an average range of 
approximately 2 ft (0.6 m) (Gore, 1992).
    At the eastern edge of the Loop Current along the west Florida 
Shelf, circulation patterns result in an upwelling of deep nutrient-
rich water. This upwelling supports a high level of biological 
activity, producing large concentrations of plankton. Nutrient levels 
(primarily nitrogen and phosphorus) are also affected by runoff from 
agricultural and urbanized areas and from submarine groundwater 
discharge, leading to red tide conditions. In the project area, red 
tide occurs on an almost annual basis (Hu et al., 2006). Red tides are 
caused by rapid growth of the species Karenia brevis, a toxic species 
which produces brevetoxins (a type of neurotoxin) that can accumulate 
in bivalves and cause mortality in marine organisms (Hu et al., 2006). 
The rapid growth of these organisms can also create a hypoxic zone 
(area with dissolved oxygen

[[Page 55648]]

concentrations below 2 mg/L), which can cause mortality among benthic 
communities, fish, turtles, birds, and marine mammals (Hu et al., 
2006).
    Extreme variations in water circulation patterns, tides, and wave 
heights can occur along the west Florida coast during periodic tropical 
storms and hurricanes. Warm water within the Loop Current can act as an 
energy source in summer and fall months, fueling the development of 
these storms. Features of these storms that can affect natural 
circulation and topography include high winds, flooding, storm surges, 
and beach erosion.
    Tampa Bay is an estuary formed by the rise of sea level into a 
former river valley. Tampa Bay consists of four subregions, including 
lower Tampa Bay, middle Tampa Bay, Old Tampa Bay, and Hillsborough Bay. 
The project area would only extend to Port Manatee, within Lower Tampa 
Bay, near the outlet of the bay into the GOM. The bay covers an area of 
1,030 km\2\ within Hillsborough, Manatee, and Pinellas counties. 
Freshwater inflow to the bay occurs through four major river systems 
(Alafia, Hillsborough, Little Manatee, and Manatee), as well as more 
than a hundred minor creeks and rivers.
    Water circulation within the bay is driven by freshwater inflow, 
tides, and winds. The bay has an average depth of 3.5 to 4 m. There is 
well-developed horizontal stratification in the bay, with fresh water 
flowing along the surface out to sea, and denser saline water flowing 
into the bay along the bottom.
    The Tampa Bay area has a population of more than two million 
people, and tributaries, habitat, runoff patterns, and water quality 
are all affected by urbanization. Specific actions that have affected 
the bay include removal of mangroves, dumping of sewage, artificial 
filling, and modification of runoff from paved surfaces (Peene et al., 
1992).

Dates of Activity

    Port Dolphin has requested regulations governing the incidental 
take of marine mammals for the five-year period from June 2013 through 
May 2018. Construction and installation of the port and pipeline would 
last approximately 11 months, with subsequent operations (i.e., SRV 
docking and regasification) occurring for the remainder of the 
specified time period.

LNG and SRVs

    The DWPA establishes a licensing system for ownership, 
construction, and operation of deepwater ports in waters beyond the 
territorial limits of the United States. Originally, the DWPA promoted 
the construction and operation of deepwater ports as a safe and 
effective means of importing oil into the United States and 
transporting oil from the OCS, while minimizing tanker traffic and 
associated risks close to shore. The Maritime Transportation Security 
Act of 2002 amended the definition of ``deepwater port'' to include 
facilities for the importation of natural gas.
    LNG is natural gas that has been cooled to about -260 [deg]F (-162 
[deg]C) for efficient shipment and storage as a liquid. LNG is more 
compact than the gaseous equivalent, with a volumetric differential of 
about 610 to 1. LNG can thus be transported long distances across 
oceans using specially designed ships (e.g., SRVs), allowing efficient 
access to stranded reserves of natural gas that cannot be transported 
by conventional pipelines.
    This proposed STL buoy system differs from other common LNG offload 
technologies insofar as it does not involve any permanent storage or 
regasification facility at the DWP, thus minimizing required 
infrastructure at the DWP itself. Rather, STL buoys receive SRVs that 
contain onboard LNG vaporization equipment. After mooring, LNG is 
vaporized onboard the vessel and discharged via the unloading buoy and 
a flexible riser into the subsea pipeline. Because the LNG is vaporized 
with the SRV's onboard equipment, no permanent fixed or floating 
storage or vaporization facilities are required. However, this means 
that the offload process can take 5 to 8 days, as compared with a 
standard offload of 18 hours or less. As a result of this trade-off, 
continuous off-loading operations are essential to minimize 
fluctuations in the throughput of natural gas. The SRVs proposed for 
use would be equipped to transport, store, vaporize, and meter natural 
gas. A closed-loop, glycol/water-brine heat transfer system would be 
used to vaporize the LNG. Closed-loop systems burn vaporized LNG in 
order to heat an intermediate fluid (e.g., glycol/water-brine), which 
warms the LNG. The closed-loop system results in reduced environmental 
impacts on water quality and marine resources; although these systems 
do require seawater for use in cooling electrical generating equipment 
(resulting in subsequent entrainment of fish eggs and plankton, as well 
as discharge of water at elevated temperatures), such usage is 
significantly reduced from that required in an open-loop system.
    SRVs with approximate cargo capacities of either 145,000 m\3\ or 
217,000 m\3\ (189,653-283,825 yd\3\) based on standard designs for 
oceangoing LNG carriers would be used to supply LNG to the Port. 
Approximate dimensions of each SRV would range from 280 m (919 ft) in 
length and 43 m (141 ft) in breadth, with a design draft of 11.4 m 
(37.4 ft) for the smaller vessels to 315.5 m (1,035 ft) in length and 
50 m (164 ft) in breadth, with a design draft of 12 m (39 ft) for the 
larger vessels. The maximum height above the waterline would be 41.1 m 
(135 ft). The 145,000 m\3\ SRV would displace 80,000 t (88,185 ton) and 
the 217,000 m\3\ SRV would displace 108,000 t (119,050 ton). The 
vessels would be equipped with a trunk and mating cone to receive the 
unloading buoy, lifting and connection devices, an LNG vaporization 
system, and gas metering systems. All critical functions would be 
manned 24 hours per day; other functions would be accomplished on a 
regular, scheduled basis.
    The SRVs would have two thrusters forward and could have one or two 
thrusters aft. Thrusters allow precise control of positioning while 
mooring with the STL buoy. The dynamic positioning system would be used 
while retrieving the submerged unloading buoy handling line and moving 
onto the buoy. The system normally would not be used while the SRV is 
moored to the unloading buoy. SRVs would be equipped with an acoustic 
position reporting system that would monitor the buoy's draft and 
position before and during connection/disconnection; this would be 
enabled by six transponders located on the buoy itself.
    Seawater would be used to ballast the SRV, cool the dual-fuel 
diesel engines supplying power for the regasification process, and 
condense the steam produced by the boilers supplying heat to the 
vaporization process. Ballasting the SRV is required to maintain proper 
buoyancy as the LNG is vaporized and offloaded through the pipeline. 
Water intake for ballasting the SRV would require an average intake of 
360 m\3\ per hour (2.3 MGD) over the vaporization cycle. The cooling 
water system would require an additional intake of approximately 1,520 
m\3\ per hour (9.5 MGD) and would take in seawater through one of two 
sea chests, each measuring 1.5 x 2.0 m (4.9 x 6.6 ft). Water velocity 
through the lattice screens at the hull side shell would not exceed 
0.15 m/s (0.49 ft/s) at the maximum flow rate of 1,520 m\3\ per hour.
    Cooling water discharges would be made at points removed from the 
intake sea chests to avoid recirculating warmed water through the 
cooling system. All of the cooling water would be discharged

[[Page 55649]]

at a temperature of approximately 10 [deg]C (18 [deg]F) above the 
ambient water temperature. Although the seawater system would be 
equipped with a chlorination system to prevent biofouling of heat 
transfer surfaces and system components, the chlorination system would 
not be used while the SRVs are approaching the Port or moored at the 
buoys.

Port Construction

    In-water construction of Port Dolphin is expected to begin in June 
2013 and last a total of approximately 11 months. Construction would 
include siting the STL buoys and associated equipment and laying the 
marine pipeline. Construction is assumed to be continuous from 
mobilization to demobilization with no work stoppages due to weather or 
other issues. Please see Table 2-1 of Port Dolphin's application for a 
graphical depiction of the complete timeline of proposed construction 
activities. Port Dolphin anticipates that construction/installation 
would be accomplished in the following sequence:
     Install the Port Manatee HDD section, with installation 
proceeding from onshore to the offshore location.
     Install the anchor piles and the mooring lines using the 
main installation vessel at the DWP.
     Construction and installation of the HDD pipe sections for 
the segments under the existing Gulfstream pipeline.
     Install seabed pipe segments between the Port Manatee HDD 
segment and the Gulfstream HDD segments.
     Install the Skyway Bridge section of the pipe (requiring 
dredging through the causeway).
     Install the STL Buoys.
     Install the two risers from the PLEMs.
     Install the north and south PLEMs.
     Perform pipelay and diving operations towards the Y-
connector.
     Install the flowlines on the seafloor.
     Complete tie-ins and bury or armor the pipeline, as 
necessary.
     Conduct testing of the pipeline upon completion of burial 
operations.
    These components of in-water construction are discussed in greater 
detail in the following subsections.
    DWP Construction/Installation--As described previously, the Port 
would include two STL unloading buoy systems, separated by a distance 
of approximately 5 km (3.1 mi) in a water depth of approximately 31 m 
(100 ft). Each unloading buoy would have eight mooring lines, 
consisting of wire rope and chain, connecting to eight driven-pile 
anchor points on the sea floor, one 16-in (0.4-m) inside diameter 
flexible pipe riser, and one electrohydraulic control umbilical from 
the unloading buoy to the riser manifold. When not connected to a SRV, 
STL buoys would be submerged 60 to 70 ft (18 to 21 m) below the sea 
surface. A concrete or steel landing pad would be fixed to the sea 
floor by means of a skirted mud mat to allow lowering of the STL buoy 
to the ocean floor when it is not in use.
    The mooring lines would be designed so that the SRV could remain 
moored in non-hurricane 100-year storm conditions, and would vary in 
length, from 1,800 to 4,000 ft (549 to 1,219 m) for the northern 
unloading buoy and from 2,500 to 3,600 ft (762 to 1,097 m) for the 
southern buoy. The mooring lines would consist of 132-mm (5.2-in) chain 
and 120-mm (4.7-in) spiral-strand wire rope. The riser system for each 
unloading buoy would consist of one 16-in interior diameter flexible 
riser in a steep-wave configuration. Total length of the riser would be 
approximately 82 m (269 ft). The riser would be directed between two of 
the mooring lines, and would lie on the seafloor when not in use.
    The two PLEMs near the unloading buoys would connect the flexible 
risers to the flowlines and a Y-connection that would connect the two 
flowlines to the new gas transmission pipeline. Each of the two PLEMs 
would be approximately 75 m (246 ft) offset from the proposed unloading 
buoy locations. The purpose of a PLEM is to provide an interface 
between the pipeline system and the flexible riser, isolate the riser 
between gas unloading operations, and attach a subsea pig launcher or 
receiver as necessary. ``Pigs,'' or ``pipeline inspection gauges,'' 
travel remotely through a pipeline to conduct inspections of or clean 
the pipeline and collect data about conditions in the pipeline. Each 
PLEM would include a flange connection for attaching the flexible riser 
or the subsea pig launcher/receiver and a full-bore subsea hydraulic 
control valve and electrohydraulic umbilical termination assembly. Each 
PLEM would have a mud mat foundation to provide a stable base for 
bearing PLEM and riser weight and to resist sliding and overturning 
forces. Please see Figure 1-1 in Port Dolphin's application for a 
conceptual diagram of the DWP.
    Offshore installation activities at the DWP would begin with 
installation of the PLEMs at both STL buoy locations (north and south), 
followed by placement of the buoy anchors, mooring lines, buoys, and 
risers. Installation activities at both STL buoy locations would 
require a cargo barge, supported by anchor-handling support vessels, a 
supply boat, a crew transfer boat, and a tug. Buoy anchors would likely 
be installed via impact pile driving.
    Pipeline Installation--The pipeline would be laid on the seafloor 
by a pipelaying barge and then buried, typically using a plowing 
technique. Other techniques, such as dredging and HDD, are planned to 
be used in certain areas depending on the final geotechnical survey, 
engineering considerations, and equipment selection. At the western 
(seaward) end, the pipeline would consist of two 36-in (0.9-m) 
flowlines connected to the north and south PLEMs, which would connect 
at a Y-connection approximately 3.2 km (2 mi) away (see Figure 1-1 in 
Port Dolphin's application). From the Y-connection a 36-in (0.9-m) gas 
transmission line would travel approximately 74 km (46 mi) to 
interconnections with the Gulfstream and TECO pipeline systems. The 
pipelines would have a nominal outer diameter of 36 in, with a coating 
of fusion-bonded epoxy and a concrete weight coating thickness of 11.4 
cm (4.5 in).
    Pipeline trenching and burial requirements are governed by 
Department of the Interior regulations at 30 CFR 250 Subpart J, which 
requires pipelines and all related appurtenances to be protected by 3 
ft (0.9 m) of cover for all portions in water depths less than 200 ft 
(61 m). Portions of the pipeline that travel through hard-bottom areas 
may not be able to be buried to the full 3 ft depth. In these areas, 
flexible concrete mattresses or other cover would be used to cover the 
pipeline. In places where the pipeline crosses shipping lanes, it would 
be buried 10 ft (3 m) deep if the sea floor permits plowing. Burying 
the pipeline and flowlines would protect them from potential damage 
from anchors and trawls and avoid potential fouling, loss, or damage of 
fishermen's trawls. The pipeline construction corridor would be 3,000 
ft (914 m) wide in offshore areas. The permanent in-water right-of-way 
for the pipeline would be 200 ft (61 m) wide.
    Under the plowing method, the pipeline is lowered below seabed 
level by shearing a V-shaped ditch underneath it. The plow is towed 
along and underneath the pipeline by the burial barge. As the ditch is 
cut, sediment is removed and passively pushed to the side by specially 
shaped moldboards that are fitted to the main plowshare. The trench is 
then backfilled with a subsequent pass of the plow. The estimated width 
of the trench (including sediments initially pushed to each side) is 67 
ft (20.4 m) (see Figure 1-2 in Port

[[Page 55650]]

Dolphin's application for a conceptual diagram of this process).
    In areas that cannot be plowed (e.g., due to hard/live bottom) or 
complete burial cannot be achieved, the pipeline would be covered with 
an external cover (e.g., concrete mattresses or rock armoring). 
Although plowing is the preferred methodology for pipeline burial, 
other techniques such as dredging and HDD would be used where required. 
Figure 1-3 of Port Dolphin's application uses color coding of the 
proposed pipeline route to show where these various methodologies would 
be used, based on bottom structure and other barriers. The total length 
of the pipeline route is 74 km. Burial techniques to be used along the 
pipeline route and their relative lengths are characterized as follows:
     Plowing/trenching soft sediments: 39.6 km (24.6 mi; 53.2 
percent of total pipeline length);
     Plowing/external cover: 23.3 km (14.5 mi; 31.4 percent);
     External cover (concrete mattress/rock armoring): 8.5 km 
(5.3 mi; 11.7 percent);
     Clamshell dredging/dragline burial: 0.3 km (0.2 mi; 0.5 
percent); and
     HDD: 2.4 km (1.5 mi; 3.2 percent).
    HDD would be employed for installation of the pipeline at three 
locations along the inshore portion of the route. The proposed HDD 
locations include drilling from land to water at the Port Manatee shore 
approach and from water-to-water at two crossings of the existing 
Gulfstream pipeline. The eastern HDD crossing would be 898 m (2,947 ft) 
in length, and the western HDD crossing would be 407 m (1,335 ft) in 
length. Both crossings would be in a water depth of 6.4 m (21 ft). The 
Port Dolphin pipeline would be drilled to a depth of approximately 6 m 
(20 ft) below the existing Gulfstream Pipeline (Port Dolphin, 2007b).
    HDD is a steerable method of installing pipelines underground along 
a prescribed bore path, with minimal impact on the surrounding area. 
The process starts with location of entry and exit points. The first 
stage drills a pilot hole on the designed path, and the second stage 
enlarges the hole by passing a larger cutting tool known as a reamer. 
This would involve using progressively larger drill strings to 
eventually produce a drill bore 48 in (1.22 m) in diameter. The third 
stage places the product or casing pipe in the enlarged hole by way of 
the drill steel and is pulled behind the reamer to allow centering of 
the pipe in the newly reamed path. Simultaneously, bucket dredging 
would be employed to produce an exit hole at the end of the bore. In-
water HDD may involve significant distance between the seabed and the 
drilling rig, and so a casing pipe may be required during the initial 
pilot hole drilling to provide some rigidity to the drill pipe as it is 
pushed ahead by the rig. Structures known as ``goal posts'' provide 
support for the casing pipe and are typically comprised of two driven 
piles with cross members set at predetermined elevations.
    Port Dolphin has identified the need to install goal posts as part 
of the HDD drilling effort at the two water-to-water HDD locations. One 
potential option is that the goal posts are designed to self-install; 
however, another option is that drilling may be required. Further, at 
the shore-to-water transition HDD, Port Dolphin would need to install 
sheet piling to form a coffer dam, designed to contain the HDD exit pit 
so as to not impact nearby aquatic vegetation. Sheet pile segments 
would be installed by vibratory means.
    Clam shell dredging would be required for passage under the Skyway 
Bridge and would be performed from a fixed working platform. Although 
dredging, followed by conventional lay and bury, is the most likely 
scenario, HDD remains a possibility for this segment. In the area near 
Manbirtee Key, a flotation ditch--dredging operations may require such 
a ditch when the minimum water depth necessary to safely float 
equipment is not present--would be dredged using conventional dredging 
equipment (i.e., the same barge that would be used to pull-in the shore 
approach HDD). The anticipated locations where the various methods of 
pipeline installation would be used are shown in Figure 1-3 of Port 
Dolphin's application.
    There are eleven locations where tie-in operations would be 
required to piece the pipeline sections together. This mechanical 
operation is accomplished with specially designed connectors and a 
manned diving rig. This common operation does not require welding. Tie-
ins would be required at each end of all HDD crossings, the Y-
connection, and the PLEMs.
    Construction Vessels--A shallow-water lay barge, spud barge and 
clamshell dredge, and a jack-up barge would be mobilized for offshore 
pipe-laying activities. Jack-up barges are mobile work platforms that 
are fitted with long support legs that can be raised or lowered; upon 
arrival at the work location the legs would be lowered and the barge 
itself raised above the water such that wave, tidal and current loading 
acts only on the relatively slender legs and not on the barge hull. A 
spud barge is a type of jack-up barge that typically offers increased 
stability but does not raise the hull above the water. This equipment 
would be used where conventional installation methods are anticipated. 
An HDD spread, including four jack-up barges, three hopper barges 
(designed to carry materials), and two tugs for barge towing, would be 
used for the three planned HDD segments. Four diving support vessels 
would also support tie-in and mattressing operations. Construction 
equipment would make one round-trip to the project location, staying on 
location for the duration of construction activity. Work crew vessels 
and supply vessels would make on average two trips a day for the 
duration of offshore construction. Work crew and supply vessels are 
expected to make between 420 and 450 round-trips to the offshore 
construction location from shore-based facilities for the duration of 
the project.
    Table 1 details the vessels that would be used during the DWP and 
pipeline construction and installation activities. The projected 
duration and duty load of each vessel are also provided. Duty load is a 
primary consideration when characterizing project-related sound 
sources.

    Table 1--Vessels To Be Employed During Port Dolphin Construction and/or Facility Installation Operations
----------------------------------------------------------------------------------------------------------------
                                                                   Engine specifications
             Operation                Auxiliary equipment/notes             \1\            Operational usage \2\
----------------------------------------------------------------------------------------------------------------
                                        Construction/Installation at DWP
----------------------------------------------------------------------------------------------------------------
Barge..............................  ...........................  N/A...................  3.5 months at 100%.
Anchor-handling support vessels....  ROV winches, hydraulic       2 x 3,750-hp..........
                                      pumps, thrusters, sonar,
                                      survey equipment.
Supply boat........................  Bow thruster...............  671-hp................

[[Page 55651]]

 
Crew transfer boat.................  ...........................  671-hp................
Tug................................  ...........................  800-hp................
Impact hammer......................  ...........................  N/A...................  As required.
----------------------------------------------------------------------------------------------------------------
                                              Pipeline installation
----------------------------------------------------------------------------------------------------------------
Jack-up: Port Manatee HDD..........  Jack-up....................  3,000-hp..............  27 days at 50%.
Spud lay barge: Shallow lay          Tug........................  1,200-hp..............  59.4 days at 75%.
 operation; no propulsion; uses two
 tugs.
                                     Tug........................  1,200-hp..............
East jack-ups......................  Jack-up....................  3,000-hp..............  27 days at 75%.
                                     Jack-up....................  3,000-hp..............
West jack-ups......................  Jack-up....................  3,000-hp..............  27 days at 75%.
                                     Jack-up....................  3,000-hp..............
Pipelay barge: Large lay barge       Tug........................  2,000-hp..............  37 days at 85%.
 operation; no propulsion; uses two
 tugs.
                                     Tug........................  2,000-hp..............
Dragline barge.....................  ...........................  600-hp................  6 days at 100%.
Plow lay barge: Plow burial          Tug........................  2,000-hp..............  113 days at 85%.
 operation; no propulsion; uses two
 tugs.
                                     Tug........................  2,000-hp..............
DSVs for mattress armoring.........  Vessel.....................  1,000-hp..............  108 days at 100%.
                                     Vessel.....................  1,000-hp..............
DSVs for mattress armoring.........  Vessel.....................  1,000-hp..............  12 days at 15%.
                                     ...........................  1,000-hp..............
                                     Vessel.....................  1,000-hp..............
                                     ...........................  1,000-hp..............
Pipeline gauge, fill, test,          Vessel.....................  300-hp................  13 days at 35%.
 dewater, and drying.
                                     ...........................  300-hp................
                                     Vessel.....................  300-hp................
                                     ...........................  300-hp................
Survey vessel......................  Vessel.....................  1,000-hp..............  54 days at 50%.
                                     Vessel.....................  1,000-hp..............
Spud lay barge: Shallow lay barge    Tug........................  1,200-hp..............  6.6 days at 15%.
 operation; no propulsion; uses two
 tugs.
                                     Tug........................  1,200-hp..............
East jack-ups......................  Jack-up....................  2,000-hp..............  3 days at 15%.
                                     Jack-up....................  2,000-hp..............
West jack-ups......................  Jack-up....................  2,000-hp..............  3 days at 15%.
                                     Jack-up....................  2,000-hp..............
Pipelay barge: Large lay barge       Tug........................  2,000-hp..............  4 days at 15%.
 operation; no propulsion; uses two
 tugs.
                                     Tug........................  2,000-hp..............
Dragline barge.....................  Barge......................  600-hp................  1 day at 15%.
Plow lay barge: Plow burial          Tug........................  2,000-hp..............  13 days at 15%.
 operation; no propulsion; uses two
 tugs.
                                     Tug........................  2,000-hp..............
DSVs for mattress armoring.........  Vessel.....................  1,000-hp..............  12 days at 15%.
                                     ...........................  1,000-hp..............
                                     Vessel.....................  1,000-hp..............
                                     ...........................  1,000-hp..............
Pipeline gauge, fill, test,          Vessel.....................  300-hp................  1 day at 15%.
 dewater, and drying.
                                     ...........................  300-hp................
                                     Vessel.....................  300-hp................
                                     ...........................  300-hp................
Survey vessel......................  Vessel.....................  1,000-hp..............  6 days at 15%.
----------------------------------------------------------------------------------------------------------------
                                                 HDD operations
----------------------------------------------------------------------------------------------------------------
Jack-up: Port Manatee HDD..........  Jack-up....................  3,000-hp..............  3 days at 15%.
Spud barge.........................  Crane-mounted drill and      N/A...................  Maximum 4 days for
                                      vibratory drill; ancillary                           vibratory drilling at
                                      equipment includes welding                           each HDD location.
                                      equipment, air compressor,
                                      and generator.
Tug................................  ...........................  800-hp................  Maximum 4 days for
                                                                                           vibratory drilling at
                                                                                           each HDD location.
----------------------------------------------------------------------------------------------------------------
DSV = Diving spread vessels
\1\ All specifications are for diesel engines.
\2\ All figures assume 24 hrs/day; percentages refer to percent maximum duty load.


[[Page 55652]]

Port Operations

    The proposed DWP operations would include SRV maneuvering/docking, 
regasification of LNG cargo, and debarkation. The SRVs are expected to 
approach the DWP from the south. In the open ocean, the SRVs typically 
travel at speeds of up to 19.5 kn (36.1 km/hr), reducing to less than 
14 kn (25.9 km/hr) while maintaining full maneuvering speed. However, 
once approaching the vicinity of the DWP--within approximately 16 to 25 
km (10-16 mi) of the DWP--the SRVs would begin approach by slowing to 
about half speed, and then to slow ahead. Inside of 5 km (3.1 km) from 
the DWP, the SRVs' main engines would be placed in dead slow ahead and 
decreased upon approach to dead slow, with final positioning and 
docking to occur using thrusters. Expected SRV transit, approach, and 
maneuvering/docking characteristics are outlined in Table 2. Only the 
maneuvering/docking activities and their associated sound sources 
(i.e., thrusters) are considered in this document; transit and approach 
maneuvers are considered part of routine vessel transit and are not 
considered further.

   Table 2--SRV Speeds and Thruster Use During Transit, Approach, and
                Maneuvering/Docking Operations at the DWP
------------------------------------------------------------------------
              Zone                    Speed limit      Thrusters in use?
------------------------------------------------------------------------
>33 km from DWP.................  Full service speed  No
                                   (19.5 kn).
25-33 km from DWP...............  Full maneuvering    No
                                   speed (<14 kn).
16-25 km from DWP...............  Half ahead (<10     No
                                   kn).
5-16 km from DWP................  Slow ahead (<6 kn)  No
Inside 5 km from DWP............  Dead slow ahead     Bow and stern
                                   (<4.5 kn,           thrusters
                                   decreasing to <3
                                   kn).
Docking.........................  Dead slow.........  Two bow thrusters;
                                                       possibly one or
                                                       two stern
                                                       thrusters
------------------------------------------------------------------------

    Based on a regasification cycle of approximately 8 days and 
projected DWP throughput during the first several years of 400 MMscfd, 
vessel traffic during operations is projected to consist of a maximum 
of 46 SRV trips per year. During DWP operations, sound would be 
generated by the maneuvering of SRVs upon approach to the Port, 
regasification of LNG aboard the SRVs, and subsequent debarkation from 
the Port.
    Once an SRV is connected to a buoy, the vaporization of LNG and 
send-out of natural gas can begin. Each SRV would be equipped with up 
to five vaporization units, each with the capacity to vaporize 250 
MMscfd. Under normal operation, two or more units would be in service 
simultaneously, with at least one unit on standby mode.

Method of Incidental Taking

    Incidental take is anticipated to result from elevated levels of 
sound introduced into the marine environment by the construction and 
operation of the DWP, as described in preceding sections. Specifically, 
sound from pile driving, drilling, dredging, and vessel operations 
during the construction and installation phase, and sound from SRV 
maneuvering, docking, and regasification during operations would likely 
result in the behavioral harassment of marine mammals present in the 
vicinity. Table 3 shows these proposed activities by the time of year 
they are anticipated to occur.

      Table 3--Projected Construction, Installation, and Operations
                          Activities, by Season
------------------------------------------------------------------------
                 Activity                              Season
------------------------------------------------------------------------
                      Construction and installation
------------------------------------------------------------------------
Buoy installation.........................  Summer 2013
Offshore impact hammering.................  Summer 2013
Pipelaying offshore.......................  Late Summer 2013 through
                                             early Winter 2013-14
Pipelaying inshore........................  Late Summer 2013 through
                                             early Winter 2013-14
Offshore pipeline burial..................  Fall 2013 through Winter
                                             2013-14
Inshore pipeline burial...................  Fall 2013 through Winter
                                             2013-14
HDD.......................................  Summer 2013
HDD vibratory driving.....................  Summer 2013
------------------------------------------------------------------------
                               Operations
------------------------------------------------------------------------
SRV maneuvering/docking...................  Year-round; maximum 46
                                             visits per year
Regasification............................  Year-round; 8 days estimated
                                             per visit
------------------------------------------------------------------------

    During construction, underwater sound would be produced by 
construction vessels (e.g., barges, tugboats, and supply/service 
vessels) and machinery (e.g., pile driving and pipe laying equipment, 
trenching equipment, and goal post installation equipment at the HDD 
locations) operating either intermittently or continuously throughout 
the area during the construction period. Vessel traffic associated with 
construction would be a relatively continuous sound source during the 
construction phase. Vessel sound would be created by propulsion 
machinery, thrusters, generators, and hull vibrations and would vary 
with vessel and engine size. Machinery sound from underwater 
construction would be transmitted through water and would vary in 
duration and intensity. Port construction (i.e., field construction and 
installation operations) would require approximately 11 months.
    While the main sound source during SRV transit and approach to the 
DWP would originate from the SRV main engines (i.e., predominantly in 
low frequencies), the primary sound source during maneuvering and 
docking would be the SRV thrusters. An additional underwater sound 
source would be the sound produced by the flow of gas through the 
proposed pipeline, although very little sound would be expected to 
result (JASCO, 2008); therefore, this source is not considered further.

Description of Sound Sources

    Sound travels in waves, the basic components of which are 
frequency, wavelength, velocity, and amplitude. Frequency is the number 
of pressure waves that pass by a reference point per unit of time and 
is measured in hertz (Hz) or cycles per second. Wavelength is the 
distance between two peaks of a sound wave; lower frequency sounds have 
longer wavelengths than higher frequency sounds, which is why the lower 
frequency sound associated with the proposed activities would attenuate 
more rapidly in shallower water. Amplitude is the height of the sound 
pressure wave or the ``loudness'' of a sound and is typically measured 
using the decibel (dB) scale. A dB is the ratio

[[Page 55653]]

between a measured pressure (with sound) and a reference pressure 
(sound at a constant pressure, established by scientific standards), 
and is a logarithmic unit that accounts for large variations in 
amplitude; therefore, relatively small changes in dB ratings correspond 
to large changes in sound pressure. When referring to sound pressure 
levels (SPLs; the sound force per unit area), sound is referenced in 
the context of underwater sound pressure to 1 microPascal ([mu]Pa). One 
pascal is the pressure resulting from a force of one newton exerted 
over an area of one square meter. The source level (SL) represents the 
sound level at a distance of 1 m from the source (referenced to 1 
[mu]Pa). The received level is the sound level at the listener's 
position.
    Root mean square (rms) is the quadratic mean sound pressure over 
the duration of an impulse. Rms is calculated by squaring all of the 
sound amplitudes, averaging the squares, and then taking the square 
root of the average (Urick, 1975). Rms accounts for both positive and 
negative values; squaring the pressures makes all values positive so 
that they may be accounted for in the summation of pressure levels 
(Hastings and Popper, 2005). This measurement is often used in the 
context of discussing behavioral effects, in part because behavioral 
effects, which often result from auditory cues, may be better expressed 
through averaged units than by peak pressures.
    When underwater objects vibrate or activity occurs, sound-pressure 
waves are created. These waves alternately compress and decompress the 
water as the sound wave travels. Underwater sound waves radiate in all 
directions away from the source (similar to ripples on the surface of a 
pond), except in cases where the source is directional. The 
compressions and decompressions associated with sound waves are 
detected as changes in pressure by aquatic life and man-made sound 
receptors such as hydrophones.
    The underwater acoustic environment consists of ambient sound, 
defined as environmental background sound levels lacking a single 
source or point (Richardson et al., 1995). The ambient underwater sound 
level of a region is defined by the total acoustical energy being 
generated by known and unknown sources, including sounds from both 
natural and anthropogenic sources. These sources may include physical 
(e.g., waves, earthquakes, ice, atmospheric sound), biological (e.g., 
sounds produced by marine mammals, fish, and invertebrates), and 
anthropogenic sound (e.g., vessels, dredging, aircraft, construction). 
Even in the absence of anthropogenic sound, the sea is typically a loud 
environment. A number of sources of sound are likely to occur within 
Tampa Bay and the adjoining shelf, including the following (Richardson 
et al., 1995):
     Wind and waves: The complex interactions between wind and 
water surface, including processes such as breaking waves and wave-
induced bubble oscillations and cavitation, are a main source of 
naturally occurring ambient sound for frequencies between 200 Hz and 50 
kHz (Mitson, 1995). In general, ambient sound levels tend to increase 
with increasing wind speed and wave height. Surf sound becomes 
important near shore, with measurements collected at a distance of 8.5 
km (5.3 mi) from shore showing an increase of 10 dB in the 100 to 700 
Hz band during heavy surf conditions.
     Precipitation sound: Sound from rain and hail impacting 
the water surface can become an important component of total sound at 
frequencies above 500 Hz, and possibly down to 100 Hz during quiet 
times.
     Biological sound: Marine mammals can contribute 
significantly to ambient sound levels, as can some fish and shrimp. The 
frequency band for biological contributions is from approximately 12 Hz 
to over 100 kHz.
     Anthropogenic sound: Sources of ambient sound related to 
human activity include transportation (surface vessels and aircraft), 
dredging and construction, oil and gas drilling and production, seismic 
surveys, sonar, explosions, and ocean acoustic studies (Richardson et 
al., 1995). Shipping sound typically dominates the total ambient sound 
for frequencies between 20 and 300 Hz. In general, the frequencies of 
anthropogenic sounds are below 1 kHz and, if higher frequency sound 
levels are created, they would attenuate (decrease) rapidly (Richardson 
et al., 1995). Typical SPLs for various types of ships are presented in 
Table 4.

                               Table 4--Underwater SPLs for Representative Vessels
----------------------------------------------------------------------------------------------------------------
                      Vessel description                             Frequency (Hz)         Source level (dB)
----------------------------------------------------------------------------------------------------------------
Outboard drive; 23 ft; 2 engines @ 80 hp......................                      630                      156
Twin diesel; 112 ft...........................................                      630                      159
Small supply ships; 180-279 ft................................                    1,000        125-135 (at 50 m)
Freighter; 443 ft.............................................                       41                      172
----------------------------------------------------------------------------------------------------------------
Source: Richardson et al., 1995.

    The sum of the various natural and anthropogenic sound sources at 
any given location and time--which comprise ``ambient'' or 
``background'' sound--depends not only on the source levels (as 
determined by current weather conditions and levels of biological and 
shipping activity) but also on the ability of sound to propagate 
through the environment. In turn, sound propagation is dependent on the 
spatially and temporally varying properties of the water column and sea 
floor, and is frequency-dependent. As a result of the dependence on a 
large number of varying factors, the ambient sound levels at a given 
frequency and location can vary by 10-20 dB from day to day (Richardson 
et al., 1995).
    Very few measurements of ambient sound from Tampa Bay and the 
adjoining shelf are available. There are no specific data on ambient 
underwater sound levels for the area of the proposed Port and pipeline 
route. Shooter et al. (1982) analyzed approximately 12 hours of data 
collected in deep (3,280 m) waters in the western GOM and reported 
median ambient sound levels of 77-80 dB re: 1 [mu]Pa\2\/Hz. These 
levels are likely to be somewhat lower than those occurring in the 
vicinity of Tampa Bay, due in large part to the reduced contribution 
from surf in deep water.
    Known sound levels and frequency ranges associated with 
anthropogenic sources similar to those that would be used for this 
project are summarized in Table 5. Details of each of the sources are 
described in the following text.

[[Page 55654]]



     Table 5--Anticipated Source Levels for Construction/Installation and Operations at the Port Dolphin DWP
----------------------------------------------------------------------------------------------------------------
                                                                                                      Maximum
                                                                                                     broadband
                Source                            Activity                     Location            source level
                                                                                                      (re: 1
                                                                                                    [micro]Pa)
----------------------------------------------------------------------------------------------------------------
Barge.................................  Anchor installation          STL buoys (DWP)............          177 dB
                                         operations.
Tug...................................  Anchor installation          STL buoys (DWP)............          205 dB
                                         operations.
Impact hammer \1\.....................  Pile driving...............  STL buoys (DWP)............          217 dB
Barge.................................  Pipe laying................  Pipeline corridor, DWP to            174 dB
                                                                      shore.
Tug...................................  Transit....................  Offshore/Inshore...........          191 dB
Dredge................................  Dredging...................  Likely inshore, offshore if          188 dB
                                                                      necessary.
HDD...................................  Drilling...................  Two locations in Tampa Bay.          157 dB
Vibratory driving.....................  Sheet pile installation....  Two locations in Tampa Bay.          186 dB
SRV...................................  Maneuvering/docking, with    DWP........................          183 dB
                                         thrusters.
SRV...................................  Regasification.............  DWP........................          165 dB
----------------------------------------------------------------------------------------------------------------
Source: JASCO, 2008, 2010.
\1\ Source level for impact hammer estimated assuming pulse length of 100 ms.

    The sounds produced by these activities fall into one of two sound 
types: Pulsed and non-pulsed (defined in next paragraph). The 
distinction between these two general sound types is important because 
they have differing potential to cause physical effects, particularly 
with regard to hearing (e.g., Ward, 1997 in Southall et al., 2007). 
Please see Southall et al. (2007) for an in-depth discussion of these 
concepts.
    Pulsed sounds (e.g., explosions, gunshots, sonic booms, impact pile 
driving) are brief, broadband, atonal transients (ANSI, 1986; Harris, 
1998) and occur either as isolated events or repeated in some 
succession. Pulsed sounds are all characterized by a relatively rapid 
rise from ambient pressure to a maximal pressure value followed by a 
decay period that may include a period of diminishing, oscillating 
maximal and minimal pressures. Pulsed sounds generally have an 
increased capacity to induce physical injury as compared with sounds 
that lack these features.
    Non-pulse (intermittent or continuous) sounds can be tonal, 
broadband, or both. Some of these non-pulse sounds can be transient 
signals of short duration but without the essential properties of 
pulses (e.g., rapid rise time). Examples of non-pulse sounds include 
those produced by vessels, aircraft, machinery operations such as 
drilling or dredging, vibratory pile driving, and active sonar systems. 
The duration of such sounds, as received at a distance, can be greatly 
extended in a highly reverberant environment. Many of the sounds 
produced by the project would be transient in nature (i.e., the source 
moves), such as during vessel docking. Regasification sounds are 
continuous (while the SRV is docked) and stationary. The positioning 
(maneuvering and docking) of SRVs using thrusters is intermittent 
(i.e., every 8 days) and of short duration (i.e., 10 to 30 minutes).
    For this project, the only pulsive sounds are associated with pile 
driving activities at the offshore Port location (i.e., associated with 
anchor installation activities). Impact hammers (proposed for use in 
driving buoy anchors) operate by repeatedly dropping a heavy piston 
onto a pile to drive the pile into the substrate. Sound generated by 
impact hammers is characterized by rapid rise times and high peak 
levels, a potentially injurious combination (Hastings and Popper, 
2005). Vibratory hammers, which would be used to install sheet pile and 
possibly pilings for goal posts inshore, install piles by vibrating 
them and allowing the weight of the hammer to push them into the 
sediment. Vibratory hammers produce significantly less sound than 
impact hammers. Peak SPLs may be 180 dB or greater but are generally 10 
to 20 dB lower than SPLs generated during impact pile driving of the 
same-sized pile (Caltrans, 2009). Rise time is slower, reducing the 
probability and severity of injury (USFWS, 2009), and sound energy is 
distributed over a greater amount of time (Nedwell and Edwards, 2002; 
Carlson et al., 2001).

Sound Attenuation Devices

    Sound levels can be greatly reduced during impact pile driving 
using sound attenuation devices. There are several types of sound 
attenuation devices including bubble curtains, cofferdams, and 
isolation casings (also called temporary sound attenuation piles 
[TNAP]), and cushion blocks. Port Dolphin considers the installation of 
cofferdams to be infeasible for this project. The information available 
suggests that bubble curtains, cushion blocks and caps, and TNAP design 
offer comparable levels of sound attenuation for pile driving. Port 
Dolphin proposes to implement one or more of these techniques during 
the pile driving activities needed to install components of the STL 
buoys and will make a final decision with regard to the technology to 
be used prior to beginning work.
    Bubble curtains create a column of air bubbles rising around a pile 
from the substrate to the water surface. The air bubbles absorb and 
scatter sound waves emanating from the pile, thereby reducing the sound 
energy. Bubble curtains may be confined or unconfined. An unconfined 
bubble curtain may consist of a ring seated on the substrate and 
emitting air bubbles from the bottom. A confined bubble curtain 
contains the air bubbles within a flexible or rigid sleeve made from 
plastic, cloth, or pipe. Confined bubble curtains generally offer 
higher attenuation levels than unconfined curtains because they may 
physically block sound waves and they prevent air bubbles from 
migrating away from the pile. For this reason, the confined bubble 
curtain is commonly used in areas with high current velocity (Caltrans, 
2009).
    An isolation casing is a hollow pipe that surrounds the pile, 
isolating it from the in-water work area. The casing is dewatered 
before pile driving. This device provides levels of sound attenuation 
similar to that of bubble curtains (Caltrans, 2009). Sound levels can 
be reduced by 8 to 14 dB. Cushion blocks consist of materials (e.g., 
wood, nylon) placed atop piles during impact pile driving activities to 
reduce source levels. Typically sound reduction can range from 4 to a 
maximum of 26 dB.
    Both environmental conditions and the characteristics of the sound 
attenuation device may influence the

[[Page 55655]]

effectiveness of the device. According to Caltrans (2009):
     In general, confined bubble curtains attain better sound 
attenuation levels in areas of high current than unconfined bubble 
curtains. If an unconfined device is used, high current velocity may 
sweep bubbles away from the pile, resulting in reduced levels of sound 
attenuation.
     Softer substrates may allow for a better seal for the 
device, preventing leakage of air bubbles and escape of sound waves. 
This increases the effectiveness of the device. Softer substrates also 
provide additional attenuation of sound traveling through the 
substrate.
     Flat bottom topography provides a better seal, enhancing 
effectiveness of the sound attenuation device, whereas sloped or 
undulating terrain reduces or eliminates its effectiveness.
     Air bubbles must be close to the pile; otherwise, sound 
may propagate into the water, reducing the effectiveness of the device.
     Harder substrates may transmit ground-borne sound and 
propagate it into the water column.
    The literature presents a wide array of observed attenuation 
results for bubble curtains (see, e.g., WSF, 2009; WSDOT, 2008; USFWS, 
2009; Caltrans, 2009). The variability in attenuation levels is due to 
variation in design, as well as differences in site conditions and 
difficulty in properly installing and operating in-water attenuation 
devices. As a general rule, reductions of greater than 10 dB cannot be 
reliably predicted (Caltrans, 2009).

Sound Thresholds

    Since 1997, NMFS has used generic sound exposure thresholds to 
determine when an activity in the ocean that produces sound might 
result in impacts to a marine mammal such that a take by harassment or 
injury might occur (NMFS, 2005b). To date, no studies have been 
conducted that examine impacts to marine mammals from which empirical 
sound thresholds have been established. Current NMFS practice regarding 
exposure of marine mammals to high level sounds is that cetaceans 
exposed to impulsive sounds of 180 dB rms or above are considered to 
have been taken by Level A (i.e., injurious) harassment. Behavioral 
harassment (Level B) is considered to have occurred when marine mammals 
are exposed to sounds at or above 160 dB rms for impulse sounds (e.g., 
impact pile driving) and 120 dB rms for continuous sound (e.g., vessel 
sound, vibratory pile driving) but below injurious thresholds.

Distance to Sound Thresholds

    This section details sound source modeling produced under contract 
by the applicant (JASCO, 2008, 2010) and describes the predicted 
distances to relevant regulatory sound thresholds for the specified 
activities. NMFS has determined that this information represents the 
best information available for project sound sources and has used the 
information to develop mitigation measures and to estimate potential 
incidental take in this document. The modeling scenarios considered all 
sound sources associated with the project and were developed to 
thoroughly characterize the various construction/installation and 
operation activities expected. The relevant information is summarized 
in Table 6. The equipment list associated with each activity is based 
on current construction plans for the Port (Ocean Specialists, 2007). 
For each piece of equipment specified, proxy vessels were selected from 
JASCO Research's database of underwater sound measurements. The sound 
propagation model used several parameters, including expected water 
column sound speeds, bathymetry (water depth and shape of the ocean 
bottom), and bottom geoacoustic properties (which indicate how much 
sound is reflected off of the ocean bottom), to estimate the radii of 
sound impacts (JASCO, 2008). Modeling scenario locations are depicted 
in Figure 1-4 of Port Dolphin's application. Please see Appendices C 
and D in Port Dolphin's application for a detailed description of this 
sound source modeling.

 Table 6--Representative Scenarios Modeled During the Port Dolphin Sound Source Analysis and Radial Distance to
                                                   Thresholds
----------------------------------------------------------------------------------------------------------------
                                                                                                Approximate area
           Activity                     Source            Modeled location       Distance to     encompassed by
                                                                                threshold 1,2     threshold \2\
----------------------------------------------------------------------------------------------------------------
Buoy installation.............  Crane vessel, cargo    North STL buoy;        180 dB: <0.2 km.  180 dB: <0.13 km
                                 barge, support         offshore DWP site.    120 dB: 3.9 km..   \2\
                                 vessel.                                                        120 dB: 48 km
                                                                                                 \2\
Impact hammering..............  Impact hammer........  Y-connector; offshore  180 dB: 0.18 km.  180 dB: 0.10 km
                                                        DWP site.             160 dB: 4.5 km..   \2\
                                                                                                160 dB: 64 km
                                                                                                 \2\
Pipelaying, offshore..........  Barge, two anchor      15-m isobath.........  180 dB: <0.2 km.  180 dB: <0.13 km
                                 handling tugs,                               120 dB: 7.5 km..   \2\
                                 support tug.                                                   120 dB: 177 km
                                                                                                 \2\
Pipelaying, inshore...........  Barge, two anchor      Tampa Bay............  180 dB: <0.2 km.  180 dB: <0.13 km
                                 handling tugs,                               120 dB: 6.0 km..   \2\
                                 support tug.                                                   120 dB: 113 km
                                                                                                 \2\
Pipeline burial, offshore.....  Plow system, two       15-m isobath.........  180 dB: <0.2 km.  180 dB: <0.13 km
                                 anchor handling tugs.                        120 dB: 8.4 km..   \2\
                                                                                                120 dB: 222 km
                                                                                                 \2\
Pipeline burial, inshore......  Plow system, two       Tampa Bay............  180 dB: <0.2 km.  180 dB: <0.13 km
                                 anchor handling tugs.                        120 dB: 6.7 km..   \2\
                                                                                                120 dB: 141 km
                                                                                                 \2\
HDD...........................  Floating spud barge,   Tampa Bay............  180 dB: <0.01 km  180 dB: <0.00 km
                                 crane mounted drill,                         120 dB: 0.24 km.   \2\
                                 welding equipment,                                             120 dB: 0.2 km
                                 air compressor,                                                 \2\
                                 generator.
HDD vibratory driving.........  Floating spud barge,   Tampa Bay............  180 dB: <0.01 km  180 dB: <0.00 km
                                 vibrator, welding                            120 dB: 12.6 km.   \2\
                                 equipment, air                                                 120 dB: 499 km
                                 compressor,                                                     \2\
                                 generator.
Docking at buoy, dead slow,     SRV..................  STL buoy; offshore     180 dB: <0.01 km  180 dB: <0.00 km
 two bow thrusters and one                              DWP site.             120 dB: 3.6 km..   \2\
 stern thruster.                                                                                120 dB: 41 km
                                                                                                 \2\
Regasification................  SRV..................  STL buoy; offshore     180 dB: 0.00 km.  180 dB: <0.00 km
                                                        DWP site.             120 dB: 0.17 km.   \2\
                                                                                                120 dB: 0.09 km
                                                                                                 \2\
----------------------------------------------------------------------------------------------------------------
Source: JASCO, 2008, 2010.
\1\ All distances are unweighted, 95th percentile radial distances.
\2\ For distances not given precisely (e.g., <0.2 km) area of ensonification was modeled using a radial distance
  of 200 m. Although the distance to threshold would be less than 200 m, it is not possible to specifically
  calculate the distance because the scenarios involve multiple vessel components.


[[Page 55656]]

    Note that in many cases the scenarios involve multiple pieces of 
equipment. Although equipment spacing would vary during the course of 
operations, a single layout must be assumed for modeling purposes. As 
such, where multiple vessels were involved in the scenarios listed in 
Table 6 the following layout was assumed:
     The barge used for the main operation in each scenario 
(e.g., crane vessel, pipe laying barge, pipe burial barge) was set in 
the middle of the group of vessels.
     For four or fewer tugs (anchor handling and/or support), 
tugs were spaced at a range of 100 m (328 ft) from the center of the 
barge. Note that the pipe laying/burial barge itself is 122 m long x 30 
m wide (400 x 100 ft).
    The radii to sound thresholds vary for the same activity depending 
on water depth, because the transmission of lower-frequency sound waves 
can be significantly reduced in shallower water. As a result, the radii 
to the Level A and Level B harassment isopleths in Tampa Bay (i.e., 
shallower water) are shorter than those that would occur offshore. In 
addition, much of the energy from the vessels associated with 
pipelaying occurs at low frequencies and would propagate poorly in 
shallower water.
    Although sounds created by construction equipment and vessels would 
be continuous during pipeline installation, activities would progress 
slowly along the pipeline route as the pipeline is laid and buried and 
the trench backfilled. Any one area would be subject to the maximum 
sound levels for only 1 to 2 days at a time as the construction 
activities pass that area. Sound modeling indicates that, overall, 
operational sound associated with the proposed project is consistent 
with other man-made underwater sound sources in the area (e.g., 
commercial shipping and dredging). Appendix E of Port Dolphin's 
application presents Level B harassment sound field graphics for 
construction activities.
    Specific Activity Descriptions--As described previously, the 
applicant provided detailed sound source modeling for all sound-
producing activities associated with the project. In the following 
sections, each specific type of activity is described in terms of the 
modeling scenario; the type, duration, and timing of sound produced by 
the activity; and the radial distances to relevant sound thresholds. 
All radial distances to thresholds presented in the following sections 
are modeled, and may be different from the actual distances as 
determined through site-specific acoustic monitoring conducted during 
the specified activities.
    Buoy Installation--Proxies were selected for the crane and support 
vessels based on vessel specifications. While a cargo barge may be 
present on-site for a portion of the operations, Port Dolphin assumed 
that this barge would typically not be under power. Installation of the 
buoys at the Port would produce continuous sound for a relatively short 
period of time during summer, with the 120-dB isopleth located 3.9 km 
(2.4 mi) from each STL buoy location.
    Impact Pile Driving--During the construction period, impact 
hammering would produce the loudest sound levels but would likely occur 
only for short periods of time. The source depth for pile driving was 
set to approximately half the local water depth. In actuality, sound 
would radiate from all portions of the pilings; this midwater column 
value is a precautionary estimate of the depth for an equivalent point 
source, as losses due to bottom and surface interactions would be less 
for a source at mid-depth than for one near the sea floor or surface. 
Impact hammering operations would involve a pipe lay barge and tugs, 
similar to pipe laying operations. However, because the potential 
impact to marine mammals is different for impulsive and continuous 
sources, impact hammering sound (an impulsive source) is considered 
separately from vessel sound (non-pulsed sources). Note that the source 
levels from impact hammering are much higher than those from the 
vessels that are likely to be on-site. Impact hammering offshore would 
encompass an area with a radius of approximately 180 m (591 ft) to the 
Level A threshold; radii to the 160-dB isopleths for this impulsive 
source would be at 4.5 km (2.8 mi).
    Pipe Laying--Pipe laying activities would generate continuous, 
transient, and variable sound levels during construction predominantly 
during fall, with some activity during late summer and early winter. 
Two sites were selected for pipe laying: one approximately midway along 
the offshore portion of the pipeline and another along the inshore 
portion. Equipment lists for the offshore and inshore sites are 
identical: a pipe laying barge, two tugs involved in re-setting of 
anchors, and a third tug in transit. Sound impacts from pipelaying 
would produce a 6.0 or 7.5 km (3.7-4.7 mi) radius to the 120-dB 
isopleth inshore and offshore, respectively.
    Pipe Burial--Pipeline burial using the plow system would generate 
continuous, transient, and variable sound levels during construction, 
primarily during fall and winter. Pipeline burial would be used 
infrequently during the construction period. Similarly to pipe laying, 
pipe burial using a trenching plow system would consist of an anchored 
barge accompanied by two anchor handling tugs. In addition, sound would 
be generated by the plow used to bury the pipeline. Detailed source 
level data were not available for plow operations. However, Aspen 
Environmental Group (2005) reported a broadband source level of 185 dB. 
Based on this information, similar source levels from dredge operations 
(Greene, 1987) were used for the applicant's modeling purposes. Note 
that the dredge source levels include the sound from the barge upon 
which the dredge is operated; consequently, a separate barge is not 
specified for plowing operations in Table 6. The modeling scenario used 
the depth of the barge hull under the water as the sound source depth, 
rather than the depth of the actual dredge work. This is because 
observations from clamshell dredging show that the highest levels of 
underwater sound are emitted from equipment on the barge (propagating 
through the hull) rather than from the scraping sounds of the dredge 
itself (Richardson et al., 1995). Pipeline burial using the plow system 
produces sound attenuating to the 120-dB isopleth at 6.7 km (4.2 mi) 
inshore and 8.4 km (5.2 mi) offshore.
    HDD--HDD within Tampa Bay would produce continuous sound levels and 
is expected to occur during summer. Installation of the goal posts 
(described previously under ``Pipeline Installation'') at each HDD 
location would produce a continuous sound for a relatively short period 
of time and would only occur during summer. HDD would be employed for 
installation of the pipeline at a number of locations along the inshore 
portion of the route, including the Port Manatee shore approach and two 
crossings of the existing Gulfstream pipeline. Drilling and vibratory 
driving (for goal posts/sheet pile) would be conducted from a floating 
spud barge approximately 41 m in length. Drilling would involve a 
crane-mounted drill, suspended from a crawler crane on the barge. The 
barge would also be equipped with welding equipment, an air compressor, 
and a generator.
    Source levels for drilling of the pilot holes are based on 
measurements made by Greene (1987) during drilling operations in the 
Beaufort Sea. As with drilling from a barge, these measurements include 
contributions from both the drill assembly itself and from equipment on 
the drill platform

[[Page 55657]]

(e.g., generators). Because the dominant sound source is equipment 
located on the drilling vessel (Richardson et al., 1995) rather than 
the drilling or scraping itself, a source level height of 2.2 m was 
used, as it was for other barge-mounted activities modeled by JASCO.
    Source levels for the vibratory driver were derived from 
measurements made by JASCO. The vibratory driver was mounted on a 
moored barge during the measurements, and so sound contributions from 
equipment on the barge are included in the source level estimates. The 
measured driver is larger than the vibratory driver planned for use at 
Port Dolphin. However, very few measurements of underwater sound exist 
for pile drivers of this size, and in most cases the available reports 
do not describe the vibratory driver used. Additionally, scaling by 
vibratory driver specifications (e.g., the eccentric moment) is made 
difficult by the fact that pile driving source levels depend not only 
on the equipment but also on the piling, substrate and environment. As 
such, JASCO's un-scaled measurements of underwater sound are used here 
as a conservative estimate of the sound likely to be generated during 
installation of the goal posts/sheet pile. As for the impact pile 
driving described previously, the source depth for pile driving was 
conservatively set to half the local water depth, i.e., 3.5 m.
    Modeling results (JASCO, 2010) indicate that the 120-dB isopleth 
would extend 240 m (787 ft) from the drilling operation, while the 120-
dB isopleth for HDD vibratory driving would extend 12.6 km (7.8 mi) 
from the source.
    SRV Docking--Once the SRV completes its approach to Port Dolphin 
and is within approximately 5.6 km (3.5 mi) of the Port, bow and stern 
thrusters would be utilized. Thruster use would vary, operating for 10 
to 30 minutes to allow for the proper positioning of the vessel and for 
connection to the STL buoy. Docking or berthing would occur at 
alternate STL buoys approximately every 8 days. Sound modeling, 
assessing the periodic use of the thrusters (i.e., every 8 days) 
producing an intermittent and moving sound, indicated that the 120-dB 
isopleth would occur at 3.6 km (2.2 mi) from the SRV.
    Operational procedures for the SRVs specify probable use of 
thrusters during approach and docking. Speed is gradually reduced as 
the SRV approaches the unloading buoys, until main propulsion is at 
dead slow. Bow and stern thrusters are used during docking. Once 
moored, ship's propulsion is not required for positioning. Based on 
these operational procedures, the sample situation described in Table 6 
was selected for modeling; i.e., docking at the northern buoy, using 
both bow thrusters and one stern thruster.
    Very little information is available on the underwater sound levels 
produced by LNG carriers. However, some data and empirical formulas 
have been developed for large tankers in general. At typical cruising 
speeds, source levels from such vessels are dominated by propeller 
cavitation (Sponagle, 1988; Seol et al., 2002). As described by LGL and 
JASCO (2005), an empirical expression for the source spectrum level (1 
Hz bandwidth) in the frequency range between 100 Hz and 10 kHz is

SL = 163 + 10 log BD\4\N\3\ f-2

where B is the number of blades, D is the propeller diameter in meters, 
N is the number of propeller revolutions per second, and f is the 
frequency in Hz. For frequencies less than 100 Hz, the source level is 
assumed to be constant at the 100 Hz level. In the case of ducted 
propellers (e.g., bow and stern thrusters), the constant is 
approximately 7 dB larger. Specifications for the main propulsion 
system are based on a typical carrier, and are similar to those 
described by LGL and JASCO (2005). Bow and stern thrusters are expected 
to be single-speed, controllable-pitch devices, with power ratings of 
2,000 kW each for the bow thrusters and 1,200 kW each for the stern 
thrusters. Based on these values, diameters and rates of revolution for 
the thrusters were based on specifications for the most common models 
currently available. The above model is not able to take into account 
the reduction in source levels that would result from a change in pitch 
at lower power outputs; hence, the modeled source levels are 
conservative (i.e., represent maximum expected levels of underwater 
sound).
    Regasification--The SRV would regasify its LNG cargo while moored 
at the STL buoy. Sound levels for regasification are low, and the 
modeling predicts that the 120-dB isopleths would be only 170 m (558 
ft) from the source.
    The following additional sources of underwater sound are expected 
to be present during construction of the DWP, but were not modeled:
     Dredging: Dredging would be involved in a few stages of 
construction, including HDD (discussed later) and pipelaying at the 
Sunshine Bridge crossing (Ocean Specialists, 2007). This would involve 
a clamshell or bucket-style dredge, operated from a barge while one or 
more additional barges carry out other tasks nearby. Measurements taken 
by JASCO during operation of a clamshell dredge indicated source levels 
of approximately 150-155 dB, i.e., roughly 20 dB lower than the source 
levels associated with the barge used during pipe laying operations. As 
such, dredging may be considered an insignificant source of sound 
compared with operation of the barges that would also be present.
     Transponders: Once the port is operational, an additional 
source of underwater sound in the vicinity of the unloading buoys would 
be the acoustic transponders installed on the buoys. Information was 
not available on the specific transponders intended for use at the DWP; 
however, specifications from commercially available buoy positioning 
transponders indicate operating frequencies of a few tens of kHz, and 
source levels of approximately 190 dB. Given this estimated broadband 
source level, we may estimate ranges to various threshold values 
assuming simple spherical spreading, i.e., RL = SL - 
20log10(r). Solving for r shows that received levels would 
drop to 180 dB at a range of approximately 3 m, and to 160 dB at a 
range of approximately 32 m; further, this sound source would be highly 
intermittent, as the transponders would only transmit, briefly, when 
interrogated by the SRV-based command unit. As such, only marine 
mammals passing very near the unloading buoys during the brief period 
of transmittance would potentially be affected, and effects from these 
sources may be considered discountable.

Comments and Responses

    On March 1, 2011, NMFS published a notice of receipt of an 
application for a Letter of Authorization (LOA) in the Federal Register 
(76 FR 11205) and requested comments and information from the public 
for 30 days. NMFS did not receive any substantive comments. Description 
of Marine Mammals in the Area of the Specified Activity
    Twenty-nine marine mammals (28 cetaceans and the Florida manatee 
[Trichechus manatus]) have documented occurrences in the GOM (Wursig et 
al., 2000). The manatee is under the jurisdiction of the U.S. Fish and 
Wildlife Service, and will not be discussed further in this document. 
Of the cetaceans, seven are mysticetes (baleen whales) and 21 are 
odontocetes (toothed whales, including dolphins). Table 7 contains a 
summary of relevant information for each of these 28 species.

[[Page 55658]]



                                  Table 7--Marine Mammals in the Gulf of Mexico
----------------------------------------------------------------------------------------------------------------
                                                                                  Typical habitat
             Species                Status \a\    Occurrence \b\ -----------------------------------------------
                                                                      Coastal          Shelf        Slope/Deep
----------------------------------------------------------------------------------------------------------------
                                                  Order Cetacea
----------------------------------------------------------------------------------------------------------------
                                               Suborder Mysticeti
----------------------------------------------------------------------------------------------------------------
Family Balaenidae:
    North Atlantic right whale                E               1   ..............              X               X
     (Eubalaena glacialis)......
Family Balaenopteridae.
    Blue whale (Balaenoptera                  E               1   ..............              X               X
     musculus)..................
    Bryde's whale (Balaenoptera   ..............              3   ..............              X               X
     edeni).....................
    Fin whale (Balaenoptera                   E               2   ..............              X               X
     physalus)..................
    Humpback whale (Megaptera                 E               2   ..............              X               X
     novaeangliae)..............
Minke whale (Balaenoptera         ..............              2   ..............              X               X
 acutorostrata).................
Sei whale (Balaenoptera                       E               2   ..............              X               X
 borealis)......................
----------------------------------------------------------------------------------------------------------------
                                               Suborder Odontoceti
----------------------------------------------------------------------------------------------------------------
Family Physeteridae:
    Dwarf sperm whale (Kogia      ..............              3   ..............              X               X
     sima)......................
    Pygmy sperm whale (Kogia      ..............              3   ..............              X               X
     breviceps).................
    Sperm whale (Physeter                     E               4   ..............              X               X
     macrocephalus).............
----------------------------------------------------------------------------------------------------------------
Family Ziphiidae:
    Blainville's beaked whale     ..............          2 \c\   ..............              X               X
     (Mesoplodon densirostris)..
    Cuvier's beaked whale         ..............          2 \c\   ..............              X               X
     (Ziphius cavirostris)......
    Gervais' beaked whale         ..............          3 \c\   ..............              X               X
     (Mesoplodon europaeus).....
    Sowerby's beaked whale        ..............          1 \c\   ..............              X               X
     (Mesoplodon bidens)........
Family Delphinidae:
    Atlantic spotted dolphin      ..............              4               X               X               X
     (Stenella frontalis).......
    Bottlenose dolphin (Tursiops  ..............              4               X               X               X
     truncatus).................
    Clymene dolphin (Stenella     ..............              4   ..............              X               X
     clymene)...................
    False killer whale            ..............              3   ..............              X               X
     (Pseudorca crassidens).....
    Fraser's dolphin              ..............              4   ..............              X               X
     (Lagenodelphis hosei)......
    Killer whale (Orcinus orca).  ..............              3   ..............  ..............              X
    Melon-headed whale            ..............              4   ..............  ..............              X
     (Peponocephala electra)....
    Pantropical spotted dolphin   ..............              4   ..............              X               X
     (Stenella attenuata).......
    Pygmy killer whale (Feresa    ..............              3   ..............              X               X
     attenuata).................
    Short-finned pilot whale      ..............              4   ..............              X               X
     (Globicephala
     macrorhynchus).............
    Risso's dolphin (Grampus      ..............              4   ..............              X               X
     griseus)...................
    Rough-toothed dolphin (Steno  ..............              4   ..............              X               X
     bredanensis)...............
    Spinner dolphin (Stenella     ..............              4   ..............              X               X
     longirostris)..............
    Striped dolphin (Stenella     ..............              4   ..............              X               X
     coeruleoalba)..............
----------------------------------------------------------------------------------------------------------------
Source: W[uuml]rsig et al., 2000
\a\ Status: E = Listed as endangered under the Endangered Species Act.
\b\ Occurrence: 1 = extralimital; 2 = rare; 3 = uncommon; 4 = common.
\c\ Beaked whales in the GOM may be somewhat more common than survey data indicate, as beaked whales are
  difficult to sight and identify to species. Most surveys have been conducted in sea states that are not
  optimal for sighting beaked whales.

    Of these 28 cetacean species, based on available survey data, only 
the bottlenose dolphin and Atlantic spotted dolphin are likely to occur 
regularly in the vicinity of the project area (i.e., coastal and shelf 
waters of the eastern GOM) (Fulling et al., 2003). Because a small 
portion of the sound produced by the activity is predicted to extend 
into the mid-shelf depth stratum, three other species of cetacean--
pygmy and dwarf sperm whales and the rough-toothed dolphin--could be 
affected. Other species of dolphins and an occasional whale are 
sometimes observed in nearshore GOM waters and might infrequently 
strand, but these are not considered normal occurrences for those 
deepwater species that occur more regularly in waters around and 
seaward of the continental shelf break (Mullin and Fulling, 2003a; 
Mullin et al., 2004). As a result, the potential effects of the 
specified activity are analyzed only for these five species. As the 
species to be most affected by the specified activity, bottlenose and 
spotted dolphin occurrences relative to the project area are discussed 
in more detail in the following paragraphs.
    The cetacean fauna of the northern and eastern GOM continental 
shelf, including the project area, typically consists of the bottlenose 
dolphin and the Atlantic spotted dolphin (Davis and Fargion, 1996; 
Jefferson and Schiro, 1997; Davis et al., 1998; Davis et al., 2000; 
W[uuml]rsig et al., 2000). At the shelf edge and within the deeper 
waters of the continental slope, the cetacean community typically 
includes nineteen species, including the Bryde's whale, sperm whale, 
pygmy and dwarf sperm whales, three species of beaked whales, and 
twelve species of oceanic dolphins. Oceanographic and bathymetric 
features (e.g., eddies, water temperature, salinity) are important 
factors in determining the distribution of marine mammals, in large 
part because the presence of prey is frequently influenced by such 
features (Katona and Whitehead, 1988; Biggs et al., 2000; Wormuth et 
al., 2000; Davis et al., 2002). The presence of specific hydrographic 
and/or bathymetric features and discontinuities (e.g., abrupt

[[Page 55659]]

temperature differentials, current edges, upwelling areas, sea mounts, 
banks, shoals, the continental shelf edge) may also affect marine 
mammal distribution (USDON, 2003).
    The following discussions of the population status of GOM marine 
mammals use categories adapted from W[uuml]rsig et al. (2000):
     Common: A species that is abundant and widespread 
throughout the region in which it occurs;
     Uncommon: A species that does not occur in large numbers 
and may or may not be widely distributed throughout the region in which 
it occurs;
     Rare: A species present in such small numbers throughout 
the region that it is seldom seen; and
     Extralimital: A species known on the basis of few records 
that are probably the result of unusual movements of few individuals 
into the region.
    Data historically acquired during aerial and shipboard surveys 
conducted within the eastern GOM were analyzed by marine mammal 
researchers and summarized in USDON (2003). To increase the utility of 
the species sightings data, marine mammal occurrence and distribution 
data were partitioned into both seasonal and water depth categories. 
This partitioning is supported by distribution patterns (e.g., 
sightings over the continental shelf, sightings beyond the continental 
shelf) observed during large[hyphen]scale surveys (e.g., Cetacean and 
Turtle Assessment Program [CETAP] surveys; CETAP, 1982; Hain et al., 
1985; Winn et al., 1987). Seasonal categories included in USDON (2003) 
and employed in this analysis were:
     Winter: December 21 through March 20;
     Spring: March 21 through June 20;
     Summer: June 21 through September 20; and
     Fall: September 21 through December 20.
    Water depth categories, or depth strata, included in USDON (2003) 
and employed in this analysis were as follows:
     Nearshore: 0 to 120 ft (0 to 36.6 m);
     Mid[hyphen]shelf: 120 to 300 ft (36.6 to 91.4 m);
     Shelf[hyphen]edge: 300 to 6,600 ft (91.4 to 2,000 m); and
     Slope: > 6,600 ft (> 2,000 m).
    The U.S. Department of the Navy (USDON, 2003) reviewed available 
marine mammal survey data for the eastern GOM and summarized species 
presence and distribution on a seasonal basis. Relevant findings 
pertinent to marine mammals include the following:
     Spring is the season with the highest number of cetacean 
occurrence records, although high numbers of cetacean occurrence 
records were also noted for summer;
     Fall and winter are the two seasons with the lowest number 
of occurrence records and total number of cetaceans;
     Higher numbers in spring and summer are possibly due to 
the higher survey effort usually expended during those months (when 
sighting conditions are optimal); and
     There are fewer sighting records in fall than in the other 
seasons, likely attributable to suboptimal survey conditions (i.e., 
reduction in sightability).

Mysticetes

    The Bryde's whale is the most frequently sighted mysticete in the 
Gulf, though considered uncommon. Strandings and sightings data suggest 
that this species may be present throughout the year, generally in the 
northeastern Gulf near the 100-m (328-ft) isobath between the 
Mississippi River delta and southern Florida (Davis et al., 2000; 
W[uuml]rsig et al., 2000). The remaining six mysticete whales (blue, 
fin, humpback, minke, sei, and North Atlantic right whales) are 
considered rare or extralimital in the GOM (Jefferson, 1996; Jefferson 
and Schiro, 1997). Mysticete whales, including the Bryde's whale, could 
occur within the project area although such occurrence would be 
extremely unlikely.

Odontocetes

    Bottlenose dolphins and spotted dolphins are known to occur 
regularly in the project area and are the species to be most affected 
by the project. In addition, there is some possibility that pygmy and 
dwarf sperm whales and rough-toothed dolphins could occur in deeper 
waters ensonified by some offshore project activities. Most of the 
odontocetes known to occur within the Gulf (Table 7) are considered 
common. Exceptions include the beaked whales, with most being rare or 
extralimital, and the dwarf and pygmy sperm whales, which are 
considered uncommon. The frequency of occurrence of beaked whales and 
dwarf and pygmy sperm whales are most likely underestimated because 
these cryptic species are submerged much of the time and avoid aircraft 
and ships (W[uuml]rsig et al., 1998). Consequently, these species may 
be somewhat more common than is indicated by survey data but are still 
likely to be relatively uncommon. The sperm whale is considered common 
in the Gulf (Jefferson, 1996; Jefferson and Schiro, 1997; Davis et al., 
2000; Waring et al., 2006). Sightings data suggest a Gulf[hyphen]wide 
distribution on the continental slope. Congregations of sperm whales 
are common along the continental shelf edge in the vicinity of the 
Mississippi River delta in water depths of 500 to 2,000 m (1,640-6,562 
ft). As a result of these consistent sightings, it is believed that 
there is a resident population of sperm whales in the Gulf consisting 
of adult females, calves, and immature individuals (Brandon and 
Fargion, 1993; Mullin et al., 1994; Sparks et al., 1993; Jefferson and 
Schiro, 1997). Though most odontocetes (including delphinids) are 
considered common in the GOM, they prefer waters of the continental 
shelf edge (approximately 200 m [656 ft]) or deeper waters of the 
continental slope. Therefore, it is unlikely that these species would 
occur within the project area (i.e., Tampa Bay and nearshore waters). 
Due to the rarity of the majority of odontocete species, as well as the 
mysticetes discussed previously, in the proposed project area and the 
remote chance they would be affected by Port Dolphin's proposed port 
operations, these species are not considered further in this analysis.
    The most commonly sighted cetaceans on the GOM continental shelf 
(in terms of numbers of individual sightings) during systematic surveys 
conducted in the mid to late 1990s (i.e., GulfCet II) were bottlenose 
dolphins and Atlantic spotted dolphins. Brief discussions of these 
commonly sighted marine mammal species are provided in the following 
subsections.
    Bottlenose dolphins--The bottlenose dolphin is a common inhabitant 
of both the continental shelf and slope in the GOM, generally in waters 
less than 20 m (66 ft) (Griffin and Griffin, 2003). The species is also 
distributed throughout the bays, sounds, and estuaries of the GOM 
(Mullin et al., 1990). Bottlenose dolphins are opportunistic feeders, 
taking a wide variety of fish, cephalopods, and shrimp (Wells and 
Scott, 1999) and using a wide variety of feeding strategies (Shane, 
1990). In the GOM, bottlenose dolphins often feed in association with 
shrimp trawlers (Fertl and Leatherwood, 1997). In addition to the use 
of active echolocation to find food, bottlenose dolphins likely detect 
and orient to fish prey by listening for the sounds prey produce--so-
called `passive listening' (Barros and Myrberg, 1987; Gannon et al., 
2005). Nearshore bottlenose dolphins prey predominately on coastal fish 
and cephalopods, while offshore individuals prey on pelagic cephalopods 
and a large variety of epi- and mesopelagic fish species (Van Waerebeek 
et al., 1990; Mead and Potter, 1995).

[[Page 55660]]

    NMFS recognizes several stocks of bottlenose dolphins in the GOM, 
including a northern oceanic stock; a continental shelf and slope 
stock; western, northern, and eastern coastal stocks; and a group of 32 
bay, sound, and estuarine stocks (Blaylock et al., 1995; Waring et al., 
2006). Bottlenose dolphins likely occur within both offshore and 
nearshore waters of the project area. Bottlenose dolphins present in 
the project area would likely be represented by individuals from the 
eastern coastal stock and the relevant bay, sound, and estuarine 
stocks.
    Bottlenose dolphins along the U.S. coastline are believed to be 
organized into local populations, or stocks, each occupying a small 
region of coast with some migration to and from inshore and offshore 
waters (Schmidly, 1981). The seaward boundary for coastal stocks, the 
20-m (66-ft) isobath, generally corresponds to survey strata (Scott, 
1990; Blaylock and Hoggard, 1994; Fulling et al., 2003) and represents 
a management boundary rather than an ecological boundary. Both 
``coastal/nearshore'' and ``offshore'' ecotypes of bottlenose dolphins 
(Hersh and Duffield, 1990) occur in the GOM (LeDuc and Curry, 1998), 
and both could potentially occur in coastal waters. The best abundance 
estimate available for the northern GOM eastern coastal stock of 
bottlenose dolphins is 7,702, with a minimum population estimate of 
6,551. The status of the eastern coastal stock relative to optimum 
sustainable population (OSP) level is not known and population trends 
cannot be determined due to insufficient data. The eastern coastal 
stock is not considered a strategic stock under the MMPA because the 
stock's average annual human-related mortality and serious injury does 
not exceed potential biological removal (PBR) (Waring et al., 2010).
    Bottlenose dolphins are distributed throughout the bays, sounds and 
estuaries of the GOM (Mullin, 1988). The identification of 
biologically-meaningful ``stocks'' of bottlenose dolphins in these 
waters is complicated by the high degree of behavioral variability 
exhibited by this species (Shane et al., 1986; Wells and Scott, 1999; 
Wells, 2003), and by the lack of requisite information for much of the 
region. However, distinct stocks are provisionally identified in each 
of 32 areas of contiguous, enclosed or semi-enclosed bodies of water 
adjacent to the northern GOM. Bay, sound, and estuarine dolphins found 
in the project area would likely be from Tampa Bay or Sarasota Bay.
    These ``communities'' include resident dolphins that regularly 
share large portions of their ranges, exhibit similar distinct genetic 
profiles, and interact with each other to a much greater extent than 
with dolphins in adjacent waters. While these communities do not 
constitute closed demographic populations, the geographic nature of 
these areas and long-term, multi-generational stability of residency 
patterns suggest that they may exist as discrete, functioning units of 
their ecosystems. Members of these stocks emphasize use of the bay, 
sound, or estuary waters, with limited movements through passes to the 
GOM (Shane, 1977, 1990; Gruber, 1981; Irvine et al., 1981; Maze and 
W[uuml]rsig, 1999; Lynn and W[uuml]rsig, 2002; Fazioli et al., 2006). 
These habitat use patterns are reflected in the ecology of the dolphins 
in some areas; for example, residents of Sarasota Bay, Florida, lack 
squid in their diet, unlike non-resident dolphins found stranded on 
nearby Gulf beaches (Barros and Wells, 1998).
    Genetic exchange occurs between resident communities; hence the 
application of the demographically and behaviorally-based term 
``community'' rather than ``population'' (Wells, 1986a; Sellas et al., 
2005). A variety of potential exchange mechanisms occur in the Gulf. 
Small numbers of inshore dolphins traveling between regions have been 
reported, with patterns ranging from traveling through adjacent 
communities (Wells, 1986b; Wells et al., 1996a,b) to movements over 
distances of several hundred kilometers in Texas waters (Gruber, 1981; 
Lynn and W[uuml]rsig, 2002). In many areas, year-round residents co-
occur with non-resident dolphins, providing potential opportunities for 
genetic exchange. Non-residents exhibit a variety of patterns, ranging 
from apparent nomadism recorded as transience to apparent seasonal or 
non-seasonal migrations. Passes, especially the mouths of the larger 
estuaries, serve as mixing areas. For example, several communities mix 
at the mouth of Tampa Bay (Wells, 1986a). Seasonal movements of 
dolphins into and out of some of the bays, sounds and estuaries provide 
additional opportunities for genetic exchange with residents, and 
complicate the identification of stocks in coastal and inshore waters.
    In larger bay systems (e.g., Tampa Bay), seasonal changes in 
abundance suggest possible migrations, and fall/winter increases in 
abundance have been noted for Tampa Bay (Scott et al., 1989). A number 
of geographically and socially distinct subgroupings of dolphins in 
some regions, including Tampa Bay, have been identified, but the 
importance of these distinctions to stock designations remains 
undetermined. For Tampa Bay, Urian et al. (2009) recently described 
fine-scale population structuring into five discrete communities 
(including the adjacent Sarasota Bay community) that differed in their 
social interactions and ranging patterns. Structure was found despite a 
lack of physiographic barriers to movement within this large, open 
embayment.
    In the vicinity of the action area, there are distinct geographic 
subdivisions with year-round resident animals from Tampa Bay, Sarasota 
Bay, and Charlotte Harbor as well as a seasonal coastal stock 
(discussed previously; 1 to 12 km [0.6-7.5 mi] offshore) with mixing on 
a limited basis (Wells et al., 1996; Wells and Scott, 2002; Sellas et 
al., 2005). The Sarasota community's range extends from southern Tampa 
Bay southward through Sarasota Bay, and into the GOM about 1 km 
offshore. Waring et al. (2010) identified the animals in Tampa Bay as 
having a best estimate of abundance of 559 individuals (based on 1994 
data) and those in Sarasota Bay as having a best abundance estimate of 
160 individuals (based on 2007 data). The status of the stock relative 
to OSP is unknown. Because most of the stock sizes are currently 
unknown, but likely small, and relatively few mortalities or serious 
injuries would exceed PBR, NMFS considers that each of these stocks is 
a strategic stock under the MMPA (Waring et al., 2010).
    Atlantic spotted dolphins--Atlantic spotted dolphins are widely 
distributed in warm temperate and tropical waters of the Atlantic 
Ocean, including the GOM (Waring et al., 2006). In the northern Gulf, 
these animals occur mainly on the continental shelf (Jefferson and 
Schiro, 1997). During GulfCet II aerial and shipboard surveys in the 
northern GOM, Atlantic spotted dolphins were seen at water depths 
ranging from 22 to 222 m (72-728 ft) (Mullin and Hoggard, 2000). On the 
shelf, they were second in abundance to bottlenose dolphins. Atlantic 
spotted dolphins can be expected to occur on the continental shelf 
during all seasons. However, they may be more common during spring 
(Jefferson and Schiro, 1997; Mullin and Hoggard, 2000). It is expected 
that Atlantic spotted dolphins could occur within offshore waters of 
the project area.
    Atlantic spotted dolphins in the northern GOM are abundant in 
continental shelf waters from between 10 and 200 m (33 to 656 ft) to 
slope waters < 500 m (1,640 ft) (Fulling et al. 2003; Mullin and 
Fulling, 2003a). Griffin and Griffin (2003) reported that

[[Page 55661]]

on the west Florida Shelf they are more common in waters from 20 to 180 
m (66 to 591 ft), while Mullin et al. (2004) found that Atlantic 
spotted dolphins were sighted in waters with a bottom depth typically < 
300 m (984 ft). Griffin and Griffin (2004) reported higher abundances 
of spotted dolphins on the west Florida Shelf between the months of 
November and May than during the rest of the year.
    Atlantic spotted dolphins in the GOM have been seen feeding 
cooperatively on clupeid fishes (e.g., herring, sardine) and are known 
to feed in association with shrimp trawlers (Fertl and W[uuml]rsig, 
1995; Fertl and Leatherwood, 1997, respectively). In the Bahamas, this 
species has been observed to chase and catch flying fish (MacLeod et 
al., 2004). The only information on dive depth for this species is 
based on a satellite-tagged individual from the GOM (Davis et al., 
1996). This individual made short, shallow dives (more than 76 percent 
of the time to depths < 10 m) over the continental shelf, although some 
dives were as deep as 40 to 60 m (Davis et al., 1996).
    The GOM population is considered a separate stock for management 
purposes. The most recent abundance estimate for Atlantic spotted 
dolphin in the GOM, based on pooled survey data from 2000 and 2001, was 
37,611 (Waring et al., 2009). These animals were found entirely in OCS 
waters; the abundance estimate for oceanic waters, from surveys 
conducted in 2003-04, was zero. There is insufficient information for 
this stock to determine PBR or its status relative to OSP. Despite an 
undetermined PBR and unknown population size, the GOM stock is not 
considered a strategic stock under the MMPA because previous estimates 
of population size have been large compared to the number of cases of 
documented human-related mortality and serious injury.
    In addition to bottlenose and spotted dolphins, three other species 
that frequent the mid-shelf stratum could be exposed to sound from 
certain project activities and the potential for incidental harassment 
of these species has been evaluated (see ESTIMATED INCIDENTAL 
HARASSMENT). Dwarf and pygmy sperm whales and rough-toothed dolphins 
may be expected to occur in the mid-shelf stratum on a seasonal basis. 
The area of actual construction and operations for Port Dolphin is 
entirely contained within the nearshore depth stratum (0 to 37 m; depth 
strata were listed earlier). Maximum depth at the DWP is approximately 
31 m, while the pipeline route transits increasingly shallower waters 
until entering Tampa Bay and subsequently making landfall. However, 
while the actual construction activities will be entirely contained 
within the nearshore stratum, the sound field produced by certain 
construction activity, and thus the area of effect, extends into the 
mid-shelf depth stratum (37 to 91 m). Most sound would be contained 
within the nearshore stratum. The one exception is for the offshore 
pipelaying activity, which would occur only from late summer 2013 
through early winter 2013-14. The Level B sound field for this activity 
would be 99.9 percent contained within the nearshore stratum, with 0.1 
percent potentially entering the mid-shelf stratum.

Background on Marine Mammal Hearing

    Different kinds of marine life are sensitive to different 
frequencies of sound. Based on available behavioral data, audiograms 
derived using auditory evoked potential techniques, anatomical 
modeling, and other data, Southall et al. (2007) designated functional 
hearing groups for marine mammals and estimated the lower and upper 
frequencies of functional hearing of the groups. The functional groups 
and the associated frequencies are indicated below (though animals are 
less sensitive to sounds at the outer edge of their functional range 
and most sensitive to sounds of frequencies within a smaller range 
somewhere in the middle of their functional hearing range):
     Low-frequency cetaceans (mysticetes): Functional hearing 
is estimated to occur between approximately 7 Hz and 22 kHz;
     Mid-frequency cetaceans (dolphins, larger toothed whales, 
beaked and bottlenose whales): Functional hearing is estimated to occur 
between approximately 150 Hz and 160 kHz;
     High-frequency cetaceans (true porpoises, river dolphins, 
Kogia sp.): Functional hearing is estimated to occur between 
approximately 200 Hz and 180 kHz; and
     Pinnipeds in water: Functional hearing is estimated to 
occur between approximately 75 Hz and 75 kHz, with the greatest 
sensitivity between approximately 700 Hz and 20 kHz.
    As mentioned previously in this document, two species of cetacean, 
bottlenose and Atlantic spotted dolphins, are likely to occur in the 
project area. These two species are both classified as mid-frequency 
cetaceans (Southall et al., 2007).

Potential Effects of the Specified Activity on Marine Mammals

    Potential effects of Port Dolphin's proposed port construction and 
subsequent operations are likely to be acoustic in nature. In-water 
construction activities (e.g., pile driving, pipeline installation) and 
LNG port operations introduce sound into the marine environment and 
have the potential to have adverse impacts on marine mammals. The 
potential effects of sound from the proposed activities associated with 
the Port might include one or more of the following: Tolerance, masking 
of natural sounds, behavioral disturbance, non-auditory physical 
effects, and temporary or permanent hearing impairment (Richardson et 
al., 1995). However, for reasons discussed later in this document, Port 
Dolphin's activities would not likely cause any cases of non-auditory 
physical effects or temporary or permanent hearing impairment. As 
outlined in previous NMFS documents, the effects of sound on marine 
mammals are highly variable and can be categorized as follows (based on 
Richardson et al., 1995):
     The sound may be too weak to be heard at the location of 
the animal (i.e., lower than the prevailing ambient sound level, the 
hearing threshold of the animal at relevant frequencies, or both);
     The sound may be audible but not strong enough to elicit 
any overt behavioral response;
     The sound may elicit reactions of varying degrees and 
variable relevance to the well-being of the marine mammal. Reactions 
can range from temporary alert responses to active avoidance reactions 
such as vacating an area until the stimulus ceases, but potentially for 
longer periods of time;
     Upon repeated exposure, a marine mammal may exhibit 
diminishing responsiveness (habituation), or disturbance effects may 
persist; the latter is most likely with sounds that are highly variable 
in characteristics and unpredictable in occurrence, and associated with 
situations that a marine mammal perceives as a threat;
     Any anthropogenic sound that is strong enough to be heard 
has the potential to result in masking, or reduce the ability of a 
marine mammal to hear biological sounds at similar frequencies, 
including calls from conspecifics and underwater environmental sounds 
such as surf sound;
     If mammals remain in an area for feeding, breeding, or 
some other biologically important purpose even though there is chronic 
exposure to sound, the possibility exists for sound-induced 
physiological stress; this might

[[Page 55662]]

in turn have negative effects on the well-being or reproduction of the 
animals involved; and
     Very strong sounds have the potential to cause a temporary 
or permanent reduction in hearing sensitivity, also referred to as 
threshold shift. In terrestrial mammals, and presumably marine mammals, 
received sound levels must far exceed the animal's hearing threshold 
for there to be any temporary threshold shift (TTS). For transient 
sounds, the sound level necessary to cause TTS is inversely related to 
the duration of the sound. Received sound levels must be even higher 
for there to be risk of permanent hearing impairment (PTS). In 
addition, intense acoustic or explosive events may cause trauma to 
tissues associated with organs vital for hearing, sound production, 
respiration, and other functions. This trauma may include minor to 
severe hemorrhage.

Tolerance

    Numerous studies have shown that underwater sounds from industrial 
activities are often readily detectable by marine mammals in the water 
at distances of many kilometers. However, other studies have shown that 
marine mammals at distances more than a few kilometers away often show 
no apparent response to industrial activities of various types (Miller 
et al. 2005). This is often true even in cases when the sounds must be 
readily audible to the animals based on measured received levels and 
the hearing sensitivity of that mammal group. Although various baleen 
whales, toothed whales, and (less frequently) pinnipeds have been shown 
to react behaviorally to underwater sound from sources such as airgun 
pulses or vessels under some conditions, at other times, mammals of all 
three types have shown no overt reactions (e.g., Malme et al., 1986; 
Richardson et al., 1995; Madsen and Mohl, 2000; Croll et al., 2001; 
Jacobs and Terhune, 2002; Madsen et al., 2002; Miller et al., 2005). In 
general, small odontocetes seem to be more tolerant of exposure to some 
types of underwater sound than are baleen whales.

Masking

    Masking is the obscuring of sounds of interest to an animal by 
other sounds, typically at similar frequencies. Marine mammals are 
highly dependent on sound, and their ability to recognize sound signals 
amid other sound is important in communication and detection of both 
predators and prey. Background ambient sound may interfere with or mask 
the ability of an animal to detect a sound signal even when that signal 
is above its absolute hearing threshold. Even in the absence of 
anthropogenic sound, the marine environment is often loud. Natural 
ambient sound includes contributions from wind, waves, precipitation, 
other animals, and thermal sound, at frequencies above 30 kHz, 
resulting from molecular agitation (Richardson et al., 1995).
    In general, masking effects are expected to be less severe when 
sounds are transient than when they are continuous. The majority of 
sound produced during the construction of Port Dolphin would be 
transient. Masking is typically of greater concern for those marine 
mammals that utilize low-frequency communications, such as baleen 
whales and, as such, is not likely to occur for the mid-frequency 
cetaceans in the project area.

Disturbance

    Behavioral disturbance is one of the primary potential impacts of 
anthropogenic sound on marine mammals. Disturbance can result in a 
variety of effects, such as subtle or dramatic changes in behavior or 
displacement but may be highly dependent upon the context in which the 
potentially disturbing stimulus occurs. For example, an animal that is 
feeding may be less prone to disturbance from a given stimulus than one 
that is not. For many species and situations, there is no detailed 
information about reactions to sound. While there are no specific 
studies of the reactions of marine mammals to sounds produced by the 
construction or operation of a LNG facility, information from studies 
of marine mammal reactions to other types of continuous and transient 
anthropogenic sound (e.g., drillships) are described here as a proxy.
    Behavioral reactions of marine mammals to sound are difficult to 
predict because they are dependent on numerous factors, including 
species, maturity, experience, activity, reproductive state, time of 
day, and weather. If a marine mammal does react to an underwater sound 
by changing its behavior or moving a small distance, the impacts of 
that change may not be important to the individual, the stock, or the 
species as a whole. However, if a sound source displaces marine mammals 
from an important feeding or breeding area for a prolonged period, 
impacts on the animals could be important.
    Based on the literature reviewed in Richardson et al. (1995), most 
small and medium-sized toothed whales exposed to prolonged or repeated 
underwater sounds are unlikely to be displaced unless the overall 
received level is at least 140 dB, although the limited available data 
indicate that the sperm whale is sometimes, though not always, more 
responsive to underwater sounds than other toothed whales. Baleen 
whales, with better hearing sensitivities at lower sound frequencies, 
have been shown in several studies to react to continuous sounds at 
received sound levels of approximately 120 dB. Toothed whales appear to 
exhibit a greater variety of reactions to anthropogenic underwater 
sound than do baleen whales. Toothed whale reactions can vary from 
attraction (e.g., bow riding) to strong avoidance, while baleen whale 
reactions range from neutral (little or no change in behavior) to 
strong avoidance. Potential disturbance reactions of odontocetes are 
discussed in somewhat more detail.
    In their comprehensive literature review, Southall et al. (2007) 
reported that combined field and laboratory data for mid-frequency 
cetaceans exposed to non-pulse sounds did not lead to clear conclusions 
about behavioral responses that may be expected from given received 
levels of sound. In some settings, individuals in the field showed 
significant behavioral responses to exposures from 90 to 120 dB, while 
others failed to exhibit such responses for exposure to received levels 
from 120 to 150 dB. Species differences, as well as uncontrolled 
contextual variables other than exposure, are the likely reasons for 
this variability. Captive subjects were often directly reinforced with 
food for tolerating exposure to high levels of sound, which likely 
explains the disparity seen in results from field and laboratory 
settings--where exposures typically exceeded 170 dB before inducing 
behavioral responses.
    Dolphins and other toothed whales may show considerable tolerance 
of floating and bottom-founded drill rigs and their support vessels, 
though reactions are variable. Kapel (1979) reported that pilot whales 
congregated within visual range of drillships and their support vessels 
off of Greenland. Beluga whales (Delphinapterus leucas) have been 
observed swimming within 100-150 m (328-492 ft) of an artificial island 
while drilling was underway and within 1 mi (1.6 km) of a drillship 
engaged in active drilling (Fraker and Fraker, 1979, 1981). However, 
other belugas, when exposed to playbacks of drilling sounds, showed 
avoidance reactions, including altering course, increased swimming 
speed, and reversed direction of travel (Stewart et al., 1982; 
Richardson et al., 1995). Reactions of beluga whales to semi-
submersible drillship sound were less

[[Page 55663]]

pronounced than were their reactions to motorboats with outboard 
engines (Thomas et al., 1990). There may be a significant contextual 
element to these reactions.
    Morton and Symonds (2002) used census data on killer whales in 
British Columbia to evaluate avoidance of non-pulse acoustic harassment 
devices (AHDs). Avoidance ranges around the AHDs were about 2.5 mi (4 
km). Also, there was a dramatic reduction in the number of days 
resident killer whales were sighted during AHD-active periods compared 
to pre- and post-exposure periods and a nearby control site.
    Some species of small toothed whales avoid vessels when they are 
approached to within 0.5-1.5 km (0.31-0.93 mi), with occasional reports 
of avoidance at greater distances (Richardson et al., 1995). Some 
toothed whale species, especially beaked whales and belugas, appear to 
be more responsive than others. However, dolphins may tolerate vessels 
of all sizes, often approaching and riding the bow and stern waves 
(Shane et al., 1986). At other times, dolphin species that are known to 
be attracted to vessels will avoid them. Such avoidance is often linked 
to previous vessel-based harassment of the animals (Richardson et al., 
1995). Coastal bottlenose dolphins that are the object of dolphin-
watching activities have been observed to swim erratically (Acevedo, 
1991), remain submerged for longer periods of time (Janik and Thompson, 
1996; Nowacek et al., 2001), display less cohesiveness among group 
members (Cope et al., 1999), whistle more frequently (Scarpaci et al., 
2000), and rest less often (Constantine et al., 2004) when vessels were 
nearby. Pantropical spotted dolphins and spinner dolphins in the 
Eastern Tropical Pacific, where they have been targeted by commercial 
fishing vessels because of their association with tuna, display 
avoidance of survey vessels of up to 11.1 km (6.9 mi; Au and Perryman, 
1982; Hewitt, 1985), whereas spinner dolphins in the GOM were observed 
bow riding the survey vessel in all fourteen sightings during one 
survey (W[uuml]rsig et al., 1998). As evidenced by these observations, 
the level of response of odontocetes to vessels is thought to be partly 
a learned behavior, e.g., a function of habituation or a response to 
some previous negative interaction.

Hearing Impairment and Other Physiological Effects

    Temporary or permanent hearing impairment is a possibility when 
marine mammals are exposed to very strong sounds. Non-auditory 
physiological effects might also occur in marine mammals exposed to 
strong underwater sound. Possible types of non-auditory physiological 
effects or injuries that may occur in mammals close to a strong sound 
source include stress, neurological effects, bubble formation, and 
other types of organ or tissue damage. Some marine mammal species 
(e.g., beaked whales) may be especially susceptible to injury and/or 
stranding when exposed to strong pulsed sounds, particularly at higher 
frequencies. Non-auditory physiological effects are not anticipated to 
occur as a result of the proposed activities, which largely do not 
include strong pulsed sounds. The following subsections discuss in more 
detail the possibilities of TTS and PTS.
    TTS--TTS, reversible hearing loss caused by fatigue of hair cells 
and supporting structures in the inner ear, is the mildest form of 
hearing impairment that can occur during exposure to a strong sound 
(Kryter, 1985). While experiencing TTS, the hearing threshold rises, 
and a sound must be stronger in order to be heard. TTS can last from 
minutes or hours to (in cases of strong TTS) days. For sound exposures 
at or somewhat above the TTS threshold, hearing sensitivity in both 
terrestrial and marine mammals recovers rapidly after exposure to the 
sound ends.
    NMFS considers TTS to be a form of Level B harassment rather than 
injury, as it consists of fatigue to auditory structures rather than 
damage to them. The NMFS-established 180-dB injury criterion is 
considered to be the received level above which, in the view of a panel 
of bioacoustics specialists convened by NMFS before TTS measurements 
for marine mammals became available, one could not be certain that 
there would be no injurious effects, auditory or otherwise, to 
cetaceans. Few data on sound levels and durations necessary to elicit 
mild TTS have been obtained for marine mammals, and none of the 
published data concern TTS elicited by exposure to multiple pulses of 
sound.
    Human non-impulsive sound exposure guidelines are based on 
exposures of equal energy (the same sound exposure level [SEL]; SEL is 
reported here in dB re: 1 [mu]Pa\2\-s for in-water sound) producing 
equal amounts of hearing impairment regardless of how the sound energy 
is distributed in time (NIOSH, 1998). Until recently, previous marine 
mammal TTS studies have also generally supported this equal energy 
relationship (Southall et al., 2007). Three newer studies, two by 
Mooney et al. (2009a,b) on a single bottlenose dolphin either exposed 
to playbacks of U.S. Navy mid-frequency active sonar or octave-band 
sound (4-8 kHz) and one by Kastak et al. (2007) on a single California 
sea lion exposed to airborne octave-band sound (centered at 2.5 kHz), 
concluded that for all sound exposure situations, the equal energy 
relationship may not be the best indicator to predict TTS onset levels. 
Generally, with sound exposures of equal energy, quieter sound 
exposures (lower SPL) with longer duration were found to induce TTS 
onset more than those of louder (higher SPL) and shorter duration. 
Given the available data, the received level of a single seismic pulse 
(with no frequency weighting) might need to be approximately 186 dB SEL 
in order to produce brief, mild TTS.
    Data on TTS from continuous sound (such as that produced by Port 
Dolphin's proposed activities) are limited, so the available data from 
seismic activities are used as a proxy. Exposure to several strong 
seismic pulses that each have received levels near 175-180 dB SEL might 
result in slight TTS in a small odontocete, assuming the TTS threshold 
is (to a first approximation) a function of the total received pulse 
energy. Given that the SPL is approximately 10-15 dB higher than the 
SEL value for the same pulse, an odontocete would need to be exposed to 
a SPL of 190 dB in order to incur TTS.
    TTS was measured in a single, captive bottlenose dolphin after 
exposure to a continuous tone with maximum SPLs at frequencies ranging 
from 4 to 11 kHz that were gradually increased in intensity to 179 dB 
and in duration to 55 minutes (Nachtigall et al., 2003). No threshold 
shifts were measured at SPLs of 165 or 171 dB. However, at 179 dB, TTSs 
greater than 10 dB were measured during different trials with exposures 
ranging from 47 to 54 minutes. Hearing sensitivity apparently recovered 
within 45 minutes after sound exposure.
    Although underwater sound levels produced by the Port Dolphin 
project may exceed levels produced in studies that have induced TTS in 
odontocetes, there is a general lack of controlled, quantifiable field 
studies related to this phenomenon, and existing studies have had 
varied results (Southall et al., 2007). Therefore, it is difficult to 
extrapolate from these data to site-specific conditions for the Port 
Dolphin project. For example, because most of the studies have been 
conducted in laboratories, rather than in field settings, the data are 
not conclusive as to whether elevated levels of sound will cause 
odontocetes to avoid the project area, thereby reducing the likelihood 
of TTS, or whether sound will attract them, increasing the likelihood 
of TTS. In any case, there are no universally

[[Page 55664]]

accepted standards for the amount of exposure time likely to induce 
TTS. While it may be inferred that TTS could theoretically result from 
the proposed activities, it is impossible to exactly quantify the 
magnitude of exposure, the duration of the effect, or the number of 
individuals likely to be affected. Exposure is likely to be brief 
because the majority of proposed activities would be transient. It is 
expected that elevated sound would have only a negligible probability 
of causing TTS in individual odontocetes because (1) of the relatively 
low SPLs produced by most project activities; (2) the transient nature 
of most sounds produced by the activities; (3) the short duration of 
certain activities that are expected to produce higher SPLs (i.e., 
offshore pile driving); and (4) the location of the project in, 
primarily, offshore open waters where marine mammals may easily avoid 
areas of ensonification.
    PTS--When PTS occurs, there is physical damage to the sound 
receptors in the ear. In some cases, there can be total or partial 
deafness, whereas in other cases the animal has an impaired ability to 
hear sounds in specific frequency ranges.
    There is no specific evidence that exposure to underwater 
industrial sounds can cause PTS in any marine mammal (see Southall et 
al., 2007). However, given the possibility that marine mammals might 
incur TTS, there has been further speculation about the possibility 
that some individuals occurring very close to industrial activities 
might incur PTS. Richardson et al. (1995) hypothesized that PTS caused 
by prolonged exposure to continuous anthropogenic sound is unlikely to 
occur in marine mammals, at least for sounds with source levels up to 
approximately 200 dB. Single or occasional occurrences of mild TTS are 
not indicative of permanent auditory damage in terrestrial mammals. 
Relationships between TTS and PTS thresholds have not been studied in 
marine mammals but are assumed to be similar to those in humans and 
other terrestrial mammals. PTS might occur at a received sound level at 
least several decibels above that inducing mild TTS.
    Southall et al. (2007) propose that sound levels inducing 40 dB of 
TTS may result in onset of PTS in marine mammals. The authors present 
this threshold with precaution, as there are no specific studies to 
support it. Because direct studies on marine mammals are lacking, the 
authors base these recommendations on studies performed on other 
mammals. Additionally, the authors assume that multiple pulses of 
underwater sound result in the onset of PTS in mid-frequency cetaceans 
when levels reach 230 dB peak or 198 dB SEL; non-pulsed (continuous) 
sound would require levels of 230 dB peak or 215 dB SEL (Southall et 
al., 2007). Sound levels this high are not expected to occur as a 
result of the proposed activities.
    The potential effects to marine mammals described in this section 
of the document do not take into consideration the proposed monitoring 
and mitigation measures described later in this document (see the 
PROPOSED MITIGATION and PROPOSED MONITORING AND REPORTING sections). 
Because of the characteristics of sound produced by most construction 
activities (i.e., they are typically low intensity, non-pulsed, and 
transient), it is highly unlikely that marine mammals would receive 
sounds strong enough (and over a sufficient duration) to cause PTS (or 
even TTS). When taking the mitigation measures proposed for inclusion 
in the regulations into consideration (e.g., shutdown zones to prevent 
Level A harassment), it is highly unlikely that any type of hearing 
impairment would occur as a result of the proposed activities.

Anticipated Effects on Habitat

    The proposed activities could have some impacts on marine mammal 
habitat, primarily by producing temporary disturbances through elevated 
levels of underwater sound, and to a lesser extent, temporarily reduced 
water quality and temporary and permanent physical habitat alteration. 
These impacts would not be expected to have tangible direct effects to 
marine mammals, but could result in minor effects to fish or other 
elements of the marine mammal prey base. Elevated levels of sound may 
be considered to affect the habitat of marine mammals through impacts 
to acoustic space (described in previous sections) or via impacts to 
prey species. The direct loss of habitat available during construction 
due to sound impacts is expected to be minimal.

Seafloor Disturbance

    Installation of port components and pipelines would cause short- 
and long-term disruption of benthic habitat in the immediate vicinity 
of the construction areas; permanent alteration of benthic habitat 
would result from buoy anchor sweep during port operations. Destruction 
of bottom habitat, along with resident benthic organisms within the 
area, is an unavoidable component of pipeline installation. This 
affects not only the benthic communities, but also the fish assemblages 
that rely on those communities for food and/or shelter; these fish may 
in turn be preyed upon by marine mammals. Immediately upon cessation of 
disturbance, the substrate would be available for recruitment of 
benthic organisms and reestablishment of the community.
    The areas affected by seafloor disturbance are essentially 
negligible in comparison with the habitat available to marine mammals 
in the surrounding area. The pipeline route was selected to avoid 
marine protected areas and areas of submerged aquatic vegetation to the 
extent possible. During and shortly after installation of the buoy 
array components and the pipeline, marine mammal prey species are 
expected to avoid feeding in the immediate vicinity of the project 
area, thus reducing the utility of habitat in the area. Displaced 
organisms would likely return to the area shortly after construction 
activities cease.

Turbidity

    Turbidity refers to any insoluble particulate matter suspended in 
the water column that impedes light passage by scattering and absorbing 
light energy. Decreased light penetration reduces the depth of the 
photic zone, in turn reducing the depth at which primary productivity 
could occur. Impacts to marine mammals would be indirect, resulting 
from impacts to prey species. Water turbidity appears to have little or 
no direct impact on bottlenose dolphins, which are regularly seen in 
turbid waters. Turbidity may adversely affect prey species by direct 
mortality or reduction of growth rates, modifying migration patterns, 
reducing available food abundance or habitat (in part by reducing 
primary production), or burial of benthic shellfish.
    However, these potential impacts would be spatially limited and 
short-term in nature, as the suspended sediment would redeposit soon 
after the buoy system array and pipeline components were installed.

Seawater Intake and Discharge

    During the construction phase, seawater would be used for 
hydrostatic testing of the offshore pipeline and flowlines. Hydrostatic 
testing is a one-time temporary event that would require filling the 
pipeline twice; a total of approximately 24 million gallons would be 
used. Hydrostatic integrity testing could nevertheless indirectly 
impact marine mammals, because plankton and fish larvae and eggs could 
be entrained and subsequently killed by the seawater intake system. 
This could have either primary or secondary indirect impacts

[[Page 55665]]

on marine mammals through impacts to prey species.
    During regasification, seawater would be taken into an SRV through 
one of two sea chests covered with a lattice screen. Similar to uptake 
described for hydrostatic testing, marine mammals may be indirectly 
impacted through the entrainment of plankton and fish eggs and larvae. 
Cooling water would be discharged at 10 [deg]C (18[emsp14][deg]F) above 
ambient seawater temperature, and would affect a relatively small area. 
The discharge would produce detectable temperature increases over a 
maximum radius of 106 m (348 ft). The cooling water discharge is not 
expected to reach the seafloor, and would thus not impact benthic 
communities. The cooling water plume would affect a relatively small 
area. Considering the short-term nature of impacts and the overall 
amount of plankton and fish eggs and larvae in the area, these impacts 
may be considered negligible.

Sound Disturbance

    Elevated levels of sound produced by port construction and 
operation could potentially directly impact marine mammals by reducing 
the attractiveness of a given area for foraging, i.e., marine mammals 
may be less likely to forage in a given area in the presence of 
elevated levels of sound. In addition, sound may indirectly impact 
marine mammals through effects to fish or other prey species. However, 
sound produced by project activities is unlikely to be of sufficient 
intensity or duration to result in significant pathological, 
physiological, or behavioral effects to fish.
    All of the potential adverse impacts to marine mammal habitat would 
likely be indirect, and would result from impacts on the food web 
(i.e., adverse impacts directly to marine mammal prey species or to 
species lower in the food chain) from the proposed activities. The 
impact to marine mammals of temporary and permanent habitat changes 
from the proposed activities is expected to be minimal. Any potential 
impacts would likely be negligible relative to the amount of habitat 
available on the west Florida Shelf or in adjacent nearshore waters. 
These effects are summarized here:
     Seafloor disturbance and turbidity: Marine mammals could 
be indirectly impacted if benthic prey species were displaced or 
destroyed. Affected species would be expected to recover after 
construction ceased, and would represent only a small portion of food 
available to marine mammals in the area. Indirect adverse impacts of 
limited spatial extent could occur as a result of short- and long-term 
turbidity increases caused by construction and operations.
     Seawater intake and discharge: This activity, primarily 
occurring during regasification, would result in the entrainment and 
destruction of plankton and larvae and discharge of heated seawater. 
The resulting adverse impact to the prey base would be negligible.
     Sound disturbance: Elevated levels of sound during 
construction would cause temporary modification of habitat and could 
harm prey species, potentially reducing utility of habitat for marine 
mammal foraging. Elevated levels of sound during operation of the DWP 
would result in essentially permanent habitat modification to a limited 
area in the immediate vicinity of each STL buoy.
    In conclusion, NMFS has preliminarily determined that Port 
Dolphin's proposed activities are not expected to have any habitat-
related effects that could cause significant or long-term consequences 
for individual marine mammals or on the food sources that they utilize.

Proposed Mitigation

    In order to issue an incidental take authorization under section 
101(a)(5)(A) of the MMPA, NMFS must, where applicable, set forth the 
permissible methods of taking pursuant to such activity, and other 
means of effecting the least practicable adverse impact on such species 
or stock and their habitat, paying particular attention to rookeries, 
mating grounds, and areas of similar significance, and on the 
availability of such species or stock for taking for certain 
subsistence uses (where relevant). NMFS and Port Dolphin worked to 
devise a number of mitigation measures designed to minimize impacts to 
marine mammals to the level of least practicable adverse impact, 
described in the following and in Port Dolphin's Marine Protected 
Species Management Plan; please see Appendix B of Port Dolphin's 
application to review that plan in detail.
    In addition to the measures described later, Port Dolphin would 
employ the following standard mitigation measures:
     All work would be performed according to the requirements 
and conditions of the regulatory permits issued by federal, state, and 
local governments.
     Briefings would be conducted between the Port Dolphin 
project construction supervisors and the crew, protected species 
observer(s) (PSO), and acoustical monitoring team (when present) prior 
to the start of all discrete construction activities, and when new 
personnel join the work, to explain responsibilities, communication 
procedures, marine mammal monitoring protocol, and operational 
procedures.
     Port Dolphin would comply with all applicable equipment 
sound standards and ensure that all construction equipment has sound 
control devices no less effective than those provided on the original 
equipment. In addition, vessel crew and contractors would be required 
to minimize sound to the extent possible. Equipment and/or procedures 
used may include the use of enclosures and mufflers on equipment, 
minimizing the use of thrusters, and turning off engines and equipment 
when not in use.
    Additional mitigation measures, which are discussed in greater 
detail below, include the following:
     Visual monitoring program (marine mammal watch);
     Vessel strike avoidance measures;
     Line and cable entanglement avoidance measures; and
     Marine debris and waste management protocols.

Monitoring and Shutdown

    The modeling results for acoustic zones of influence (ZOIs; 
described in following sections) were used to develop mitigation 
measures for the proposed activities. Those zones would initially be 
set at the distances derived through modeling (or be larger than those 
distances), but may be adjusted as necessary on the basis of acoustic 
monitoring conducted by Port Dolphin in order to verify source levels 
and local acoustic propagation characteristics (see Proposed Monitoring 
and Reporting, later in this document). The ZOIs effectively represent 
the mitigation zone that would be established around each activity to 
prevent Level A harassment and to monitor authorized Level B harassment 
of marine mammals.
    For each of the described proposed activities, a shutdown zone (to 
include areas where SPLs equal or exceed 180 dB rms) and a disturbance 
zone (defined as where SPLs equal or exceed 120 dB or 160 dB rms for 
non-pulsed or pulsed sound sources, respectively) would be established. 
Shutdown zones include all areas where the underwater SPLs are 
anticipated to equal or exceed the Level A (injury) harassment criteria 
for marine mammals and are used in concert with mitigation monitoring 
in order to prevent the occurrence of Level A harassment. Disturbance 
zones typically include all areas where the underwater SPLs are 
anticipated to equal or exceed the Level B (behavioral) harassment 
criteria. These are intended as zones in which occurrence of marine 
mammals would be noted and recorded as

[[Page 55666]]

incidental take while also alerting PSOs to potential close approach to 
the shutdown zone. In actual practice, the disturbance zones are often 
so large as to make comprehensive monitoring and fine-scale behavioral 
observation impracticable. The initial shutdown and disturbance zones 
would be established based on the worst-case underwater sound modeled 
as described, although shutdown zones may be larger than the actual 
modeled distances. Please see the discussion of ``Distance to Sound 
Thresholds'' under ``Description of Sound Sources,'' previously in this 
document.
    Conservative shutdown zones would be employed in most instances. 
Impact pile driving (described later) and non-stationary activities 
would employ zones larger than what is predicted for the Level A 
harassment threshold. Radial distances to shutdown zones for HDD 
activities were predicted to be less than 10 m. For all activities, and 
regardless of modeled shutdown zone (applicable to HDD activities), all 
equipment would be shut down if any marine mammal enters a 
precautionary 100 yd (91 m) zone in order to avoid potential risk of 
vessel strike or direct interaction with equipment. However, these 
shutdown requirements would not be required for cases in which 
delphinids voluntarily make such close approaches to vessels (e.g., for 
bow riding). In addition, for scenarios in which the modeled sound 
source is a spread of vessels employed for a given construction task, 
the shutdown/disturbance zone would be measured from the central vessel 
in the spread, or the vessel that is the primary sound producer if it 
is not the central vessel. In most cases, the disturbance zone is of 
sufficient size to make comprehensive monitoring impracticable, 
although PSOs would be aware of the size and location of the modeled 
zone and would record any observations made within the zone as takes. 
Radial distances to Level B thresholds range up to 12.6 km; please 
refer to Table 6 for those distances.

Monitoring Protocols

    The established zones would be monitored by qualified PSOs for 
mitigation purposes, as described here. Port Dolphin's marine mammal 
monitoring plan (see Appendix B of Port Dolphin's application) would be 
implemented, requiring collection of sighting data for each marine 
mammal observed during the proposed construction activities described 
in this document.
    At least two PSOs would conduct monitoring of shutdown and 
disturbance zones (as described previously) for all concurrent 
specified construction activities during daylight hours (civil dawn to 
civil dusk). PSOs would have no other duties for the duration of the 
watch. Shutdown and disturbance zones would be monitored from an 
appropriate vantage point that affords the PSOs an optimal view of the 
sea surface while not interfering with operation of the vessel or 
in[hyphen]water activities. Full observation of the shutdown zone would 
occur for the duration of the activity.
    Monitoring would occur before, during, and after specified 
construction activity, beginning 30 minutes prior to initiation and 
concluding 30 minutes after the activity ends. If marine mammals are 
present within the shutdown zone prior to initiation, the start would 
be delayed until the animals leave the shutdown zone of their own 
volition, or until 30 minutes elapse without resighting the animal(s). 
PSOs will be on watch at all times during daylight hours when 
in[hyphen]water operations are being conducted, unless conditions 
(e.g., fog, rain, darkness) make observations impossible. If conditions 
deteriorate during daylight hours such that the sea surface 
observations are halted, visual observations must resume as soon as 
conditions permit. While activities will be permitted during low-
visibility conditions, they (1) must have been initiated following 
proper clearance of the ZOI under acceptable observation conditions; 
and (2) must be restarted, if halted for any reason, using the 
appropriate ZOI clearance procedures.
    If a marine mammal is observed approaching or entering the shutdown 
zone, the PSO will call for the immediate shutdown of in[hyphen]water 
operations. The equipment operator must comply with the shutdown order 
unless human safety is at risk. Any disagreement must be resolved after 
the shutdown takes place. Construction operations would be discontinued 
until the animal has moved outside of the shutdown zone. The animal 
would be determined to have moved outside the shutdown zone through 
visual confirmation by a qualified PSO or after 15 minutes have elapsed 
since the last sighting of the animal within the shutdown zone. The 
following additional measures would apply to visual monitoring:
     Monitoring would be conducted using binoculars and the 
unaided eye. The limits of the designated ZOI will be determined using 
binocular reticle or other equipment (e.g., electronic rangefinder, 
range stick). A GPS unit or range finder would be used for determining 
the observation location and distance to marine mammals and sound 
sources.
     Each PSO would have a dedicated two-way radio for contact 
with the other PSO or field operations manager.
    Whenever a marine mammal species is observed, the PSO will note and 
monitor the position (including relative bearing and estimated distance 
to the animal) until the animal dives or moves out of visual range of 
the PSO. The PSO will continue to observe for additional animals that 
may surface in the area. Often, there are numerous animals that may 
surface at varying time intervals. Records will be maintained of all 
marine mammal species sightings in the area, including date and time, 
weather conditions, species identification, approximate distance from 
the activity, direction and heading in relation to the activity, and 
behavioral correlation to the activity. For animals observed in the 
shutdown zone, additional information regarding actions taken, such as 
duration of the shutdown, behavior of the animal, and time spent in the 
shutdown zone will be recorded. During pile driving activities, data 
regarding the type of pile driven (e.g., material construction and pile 
dimensions), type and power of the hammer used, number of cold starts, 
strikes per minute, and duration of the pile driving activities will be 
recorded.
    Monitoring would be conducted by qualified PSOs. In order to be 
considered qualified, PSOs must meet the following criteria:
     Visual acuity in both eyes (correction is permissible) 
sufficient for discernment of moving targets at the water's surface 
with ability to estimate target size and distance; use of binoculars 
may be necessary to correctly identify the target.
     Advanced education in biological science, wildlife 
management, mammalogy, or related fields (bachelor's degree or higher 
is required).
     Experience and ability to conduct field observations and 
collect data according to assigned protocols (this may include academic 
experience).
     Experience or training in the field identification of 
marine mammals, including the identification of behaviors.
     Sufficient training, orientation, or experience with the 
construction operation to provide for personal safety during 
observations.
     Writing skills sufficient to prepare a report of 
observations, including, but not limited to, the number and species of 
marine mammals observed; dates and times when in-water construction 
activities were conducted; dates and

[[Page 55667]]

times when in-water construction activities were suspended to avoid 
potential incidental injury from construction sound of marine mammals 
observed within a defined shutdown zone; and marine mammal behavior.
     Ability to communicate orally, by radio or in person, with 
project personnel to provide real-time information on marine mammals 
observed in the area as necessary.

Pile Driving

    Mitigation measures specific to pile driving would include use of 
(1) a sound attenuation device and (2) ramp-up procedures. In addition, 
the power of impact hammers will be reduced to minimum energy levels 
required to drive a pile, thus reducing the amount of sound produced in 
the marine environment. As for other construction activities, vibratory 
pile driving may continue into nighttime hours/low-visibility 
conditions only if ramp-up protocols have been conducted under 
acceptable observation conditions. Impact pile driving may occur only 
during daylight hours of good visibility. In the event of a shutdown 
during low-visibility conditions, the pile driving cannot resume until 
visual monitoring activities are resumed under acceptable observation 
conditions. The minimum shutdown zone for impact pile driving would be 
established conservatively at 250 m.
    One or more sound attenuation device will be utilized during all 
impact pile driving activities needed to install components of the STL 
buoys at the deepwater port. The sound attenuation device(s) will be 
selected and designed by the marine construction and design 
contractor(s), but would likely be either a bubble curtain or a 
temporary sound attenuation pile (TNAP), potentially used in 
conjunction with cushion block. Please see the discussion of ``Sound 
Attenuation Devices'' under ``Description of Sound Sources,'' 
previously in this document.
    The objective of a ramp-up is to alert any animals close to the 
activity and allow them time to move away, which would expose fewer 
animals to loud sounds. This procedure also ensures that any marine 
mammals missed during shutdown zone monitoring would move away from the 
activity and not be injured. The following ramp-up procedures would be 
used for in-water pile installation:
     To allow any marine mammals that may be in the immediate 
area to leave before pile driving reaches full energy, a ramp-up 
technique would be used at the beginning of each day's in-water pile 
driving activities or if pile driving has ceased for more than 1 hour.
     If a vibratory driver is used, contractors would be 
required to initiate sound from vibratory hammers for 15 seconds at 
reduced energy followed by a 1-minute waiting period. The procedure 
would be repeated two additional times before full energy may be 
achieved.
     If a non-diesel impact hammer is used, contractors would 
be required to provide an initial set of strikes from the impact hammer 
at reduced energy, followed by a 1-minute waiting period, then two 
subsequent sets.
     If a diesel impact hammer is used, contractors would be 
required to turn on the sound attenuation device (e.g., bubble curtain 
or other approved sound attenuation device) for 15 seconds prior to 
initiating pile driving to flush marine mammals from the area.

Vessel Strike Avoidance

    Several construction and support vessels will be used during 
offshore construction activities. Certain vessel activities, including 
transits, may not be subject to the visual monitoring and shutdown 
protocols described previously in this section. Consequently, there is 
the possibility for vessel strike of protected species to occur within 
the project area. Port Dolphin would inform all personnel associated 
with the project of the potential presence of protected species. All 
vessel crew members and contractors would participate in training for 
protected species presence and emergency procedures in the unlikely 
event a protected species is struck by a vessel. Construction and 
support vessels will follow the NMFS Vessel Strike Avoidance Measures 
and Reporting for Mariners. Standard measures would be implemented to 
reduce the risk associated with vessel strikes.
    The following vessel strike mitigation measures for cetaceans for 
active construction/installation vessel operations would be implemented 
during project activities:
     Vessel operators and crews must maintain a vigilant watch 
for marine mammals and slow down or stop their vessels, to the extent 
possible as dictated by safety concerns, to avoid striking sighted 
protected species.
     Construction or support vessels, while underway, would 
remain 100 yd (91 m) from all marine mammals to the extent possible.
     If a marine mammal is within 15 m of a construction or 
support vessel underway, all operations will cease until it is > 100 yd 
from the vessel. If the marine mammal is observed within 100 yd of an 
active construction or support vessel underway, the vessel would cease 
power to the propellers as long as sea conditions permit for safety. 
After the marine mammal leaves the area the vessel would proceed with 
caution, following the guidelines below:
    [ssquf] Resume vessel at slow speeds while avoiding abrupt changes 
in direction,
    [ssquf] Stay on parallel course with the marine mammal, following 
behind or next to at an equal or lesser speed,
    [ssquf] Do not cross the path of the animal,
    [ssquf] Do not attempt to steer or direct the marine mammal away,
    [ssquf] If a marine mammal exhibits evasive or defensive behavior, 
stop the vessel until the marine mammal has left the immediate area, 
and
    [ssquf] Do not allow the vessel to come between a mother and her 
calf.
     Cetaceans can surface in unpredictable locations or 
approach slowly moving vessels. When an animal is sighted in the 
vessel's path or in close proximity to a moving vessel, the Master 
would reduce speed and shift the engine to neutral and would not engage 
the engines until the animals are clear of the area.
     If a sighted marine mammal is believed to be a North 
Atlantic right whale, federal regulation requires a minimum distance of 
500 yd (457 m) from the animal be maintained (50 CFR 224.103 (c)).
     Practical speeds would be maintained to the extent 
possible. Guidelines for speeds include the following:
    [ssquf] Reduce vessel speed to 10 kn or less when mother/calf 
pairs, pods, or large assemblages of cetaceans are observed near an 
underway vessel, when safety permits. A single cetacean at the surface 
can indicate the presence of submerged animals in the vicinity of the 
vessel; therefore, prudent precautionary measures should always be 
exercised.
    [ssquf] No wake/idle speeds where the draft of the vessel provides 
less than a 4-ft (1.2-m) clearance from the bottom. All vessels would 
follow deep-water routes whenever possible.
    [ssquf] All construction vessels transiting to and from the port 
from shore would not exceed 14 kn during regular operations.
    [ssquf] Avoid sudden changes in speed and direction.
    [ssquf] Speeds approaching and departing the buoys would be reduced 
to 10 kn maximum.
    [ssquf] Speeds during installation would be well under 14 kn; 
vessels may be stationary during certain phases of installation.
     If a collision seems likely, emergency collision 
procedures would be followed.

[[Page 55668]]

     Members of the vessel crew would be encouraged to undergo 
NMFS training prior to activity, including instruction in reporting 
procedures, collision emergency procedures, and marine mammal presence 
detection (surfacing near wake).
     During construction of the facility, an Environmental 
Coordinator would be on site and responsible for communicating with 
NMFS and other relevant agencies, as appropriate.
     During construction/installation, transiting vessels would 
have lookouts required to scan for surfacing marine mammals and report 
sightings to the Master, who would notify the Environmental 
Coordinator.
     Offshore vessel activities not required to implement 
visual monitoring protocols described previously in this document would 
be temporarily terminated if marine mammals were observed in the area 
and there is the potential for harm of an individual. The Environmental 
Coordinator would be called in to determine the appropriate course of 
action.

Best Management Practices

    Port Dolphin, in conjunction with NMFS and other regulatory 
agencies, has proposed a number of BMPs that will reduce project 
environmental impacts. Although these measures are not designed 
specifically to reduce project impacts on marine mammals to the level 
of least practicable adverse impact, they do have the effect of either 
directly or indirectly reducing the potential for adverse effects to 
marine mammals. These BMPs are briefly described here. See Port 
Dolphin's application or Environmental Impact Statement for more 
details about these measures.
    Lighting--BMPs would be implemented to minimize the attraction of 
marine mammals to the project area and prevent potential impacts to 
protected species from nighttime lighting. Lighting would be down-
shielded to prevent unnecessary upward illumination while illuminating 
the vessel decks only. To the extent possible, they would not 
illuminate surrounding waters. Lighting used during all activities 
would be regulated according to USCG requirements, without using 
excessive wattage or quality of lights. Once an activity is completed, 
all lights used only for that activity would be extinguished.
    Entanglement--BMPs would be implemented to prevent entanglement in 
any lines or cables or siltation barriers used in any construction 
area. For example, lines, cables, and in-water barriers would not be 
made of any materials in which a protected species can become entangled 
(e.g., monofilament), would be properly secured, and would be regularly 
monitored to avoid protected species entrapment.
    Marine Debris--BMPs would be implemented to prevent potential 
impacts to protected species from debris discarded within any 
construction area, including mandatory marine debris training 
consistent with Bureau of Ocean Energy Management, Regulation, and 
Enforcement (BOEMRE) NTL 2007-G03 Marine Trash and Debris Awareness and 
Elimination (http://www.gomr.boemre.gov/homepg/regulate/regs/ntls/2007NTLs/07-g03.pdf).
    Turbidity--Measures related to turbidity are designed to reduce 
project impacts to water quality in the marine environment. These 
include requirements to reduce sediment resuspension from pipeline 
trenching and burial through the use of certain technology.

Benthic Habitat

     Anchor locations would be optimized to minimize impacts on 
benthic habitat; avoidance zones would be identified of critical 
habitat areas for placement of installation barge anchors. An anchoring 
plan would be developed that would provide procedures for anchor 
deployment to minimize impacts on hard- and live-bottom habitat.
     Required vessels would be selected to minimize the number 
and type of anchors, where possible, while still providing vessels 
adequate to perform the work.
     Midline buoys would be utilized to the extent practicable 
on anchor chains to reduce the amount of anchor chain sweep.
     A Mitigation Plan to compensate for unavoidable impacts on 
hard bottom would be developed.
    Pelagic Habitat--As described previously in this document, SRV 
seawater intake/discharge and other vessel discharge protocols would be 
designed to minimize impacts to water column habitat by reducing 
seawater intake requirements, creating limits for seawater intake 
velocity and discharge temperature, and reducing other vessel 
discharges.

Conclusions

    NMFS has carefully evaluated the applicant's proposed mitigation 
measures and considered a range of other measures in the context of 
ensuring that NMFS prescribes the means of effecting the least 
practicable adverse impact on the affected marine mammal species and 
stocks and their habitat. Our evaluation of potential measures included 
consideration of the following factors in relation to one another:
     The manner in which, and the degree to which, the 
successful implementation of the measure is expected to minimize 
adverse impacts to marine mammals;
     The proven or likely efficacy of the specific measure to 
minimize adverse impacts as planned; and
     The practicability of the measure for applicant 
implementation.
    Based on our evaluation of the applicant's proposed measures and 
the measures added by NMFS, NMFS has preliminarily determined that the 
mitigation measures proposed by both NMFS and Port Dolphin provide the 
means of effecting the least practicable adverse impact on marine 
mammal species or stocks and their habitat, paying particular attention 
to rookeries, mating grounds, and areas of similar significance.
    The proposed rule comment period will afford the public an 
opportunity to submit recommendations, views, and/or concerns regarding 
this action and the proposed mitigation measures. While NMFS has 
determined preliminarily that the proposed mitigation measures 
presented in this document would effect the least practicable adverse 
impact on the affected species or stocks and their habitat, NMFS will 
consider all public comments to help inform the final decision. 
Consequently, the proposed mitigation measures may be refined, 
modified, removed, or added to prior to the issuance of the final rule 
based on public comments received, and where appropriate, further 
analysis of any additional mitigation measures.

Proposed Monitoring and Reporting

    In order to issue an incidental take authorization (ITA) for an 
activity, section 101(a)(5)(A) of the MMPA states that NMFS must, where 
applicable, set forth ``requirements pertaining to the monitoring and 
reporting of such taking.'' The MMPA implementing regulations at 50 CFR 
216.104(a)(13) indicate that requests for ITAs must include the 
suggested means of accomplishing the necessary monitoring and reporting 
that would result in increased knowledge of the species and of the 
level of taking or impacts on populations of marine mammals that are 
expected to be present in the proposed action area.
    Port Dolphin proposed a protected species monitoring plan in their 
application (see Appendix B of Port

[[Page 55669]]

Dolphin's application). The plan may be modified or supplemented based 
on comments or new information received from the public during the 
public comment period. All monitoring methods identified herein have 
been developed through coordination between NMFS and Port Dolphin. The 
methods are based on the parties' professional judgment supported by 
their collective knowledge of marine mammal behavior, site conditions, 
and proposed project activities. Any modifications to this protocol 
would be coordinated with NMFS. A summary of the plan, as well as the 
proposed reporting requirements, is contained here.
    The intent of the monitoring plan is to:
     Comply with the requirements of the MMPA Letter of 
Authorization as well as the ESA section 7 consultation;
     Avoid injury to marine mammals through visual monitoring 
of identified shutdown zones; and
     To the extent possible, record the number, species, and 
behavior of marine mammals in disturbance zones for the proposed 
activities.
    As described previously, monitoring for marine mammals would be 
conducted in specific zones established to avoid or minimize effects of 
elevated levels of sound created by the specified activities. Initial 
shutdown and disturbance zones would be based on the applicant's 
modeled values. Shutdown zones for non-stationary activities would 
conform to NMFS Vessel Strike Avoidance Measures and Reporting for 
Mariners (i.e., 100 yd)--a distance much larger than actual areas 
ensonified to 180 dB rms or greater. However, shutdown requirements 
would not be triggered upon voluntary approach by small marine mammals 
(i.e., delphinids). The actual zone monitored for disturbance would be 
based upon logistical considerations, as described previously in this 
document, as the full disturbance zones would be so large as to make 
monitoring impracticable. Zones may be modified on the basis of actual 
recorded SPLs from acoustic monitoring.
    Port Dolphin proposed a visual monitoring program in its 
application. In cooperation with NMFS, Port Dolphin has supplemented 
that plan with an acoustic monitoring program that would be conducted 
primarily to verify the sound source levels and local acoustic 
propagation characteristics that were assumed in the acoustic modeling.

Acoustic Monitoring

    Port Dolphin would implement an acoustic monitoring program during 
construction and operation of the deepwater port and appurtenant marine 
facilities. Please see Port Dolphin's Sound Level Verification Plan 
(see Supplemental Information) for more detail. The objectives of this 
program are to: (1) Empirically measure the sound source levels 
associated with project activities and verify estimated source levels 
used in modelling, and (2) empirically determine ranges to relevant 
threshold levels, verifying the accuracy of the acoustic propagation 
model that was used to predict the size of sound fields generated by 
construction and operation of the port. Ambient sound levels would also 
be measured when no project activities are occurring.
    Source level measurements would be made using a combination of 
bottom deployed autonomous multi-channel acoustic recorders (AMARs) and 
cabled acoustic data acquisition and monitoring systems (ADAMs), and 
would require that accurate measurements of distance from source to the 
monitoring hydrophones be made. Range measurements are required for 
scaling the measured levels to a standard reference range (typically 
one meter from the source). Range measurements would be performed using 
a combination of GPS, radar and laser range finders. Both systems would 
obtain measurements at 1.5 m (5 ft) above the sea floor, with the depth 
of the hydrophones determined using collocated pressure-sensitive depth 
gauges. The hydrophone depth measurement is accurate to within 1 m. 
Received sound levels would be measured at pre-determined distances (as 
specified here) and would be used to determine site-specific 
propagation characteristics and verify ranges to the relevant sound 
exposure thresholds.
    The recording system would have a frequency response of 3 dB from 10 Hz to 64,000 Hz over the anticipated measurement 
range of 100 dB to 220 dB (linear peak re: 1 [mu]Pa). Hydrophones with 
differing sensitivities may be required at different locations 
depending upon the acoustic environment and source to be measured. 
Analysis of the recorded data would determine the amplitude, time 
history, and frequency of sounds associated with construction activity. 
Acoustic data to be reported include:
     Mean squared pressure (integral of the squared pressure 
for duration of impulse, divided by the impulse duration; dB re: 1 
[mu]Pa\2\/s, rms) for pulsed sounds;
     SPL (dB re: 1 [mu]Pa, rms) for non-pulsed sounds;
     The maximum averaging time and representative range of 
SPLs;
     Representative range of frequency spectra; 1/3rd octave 
band center frequency SPLs dB re:1 [mu]Pa measured over the frequency 
range of 10 Hz to 64,000 Hz; and
     Peak SPL (dB re: 1 [mu]Pa; the largest absolute value of 
the instantaneous sound pressure over the minimum frequency range of 10 
Hz to 64,000 Hz). The maximum and representative range of peak SPLs 
would be recorded for each activity.
    The activities to be monitored are:
     Pipelaying activities;
     Pipeline burial using the plow system and dredging;
     Pile driving at the buoy locations;
     Installation of the STL buoys;
     HDD within Tampa Bay;
     Vibratory driving (if conducted); and
     SRV maneuvering and docking.
    Verification of sound source levels emitted by each of the various 
activities is required. Although most types of construction activity 
would be conducted at more than one location and on more than one 
occasion during the construction period, it is only necessary to 
determine their sound source level once because local acoustic 
propagation characteristics should have little effect on the source 
level calculation. Some construction activities are of long duration 
and may vary in source level during the operation. For these longer-
duration activities (i.e., pipelaying and burial, HDD), a sound level 
monitoring program of 7 days of continuous recording at a sample rate 
of 128 kHz would be implemented to capture and consider potential 
variability when determining the source level associated with these 
activities. During the 7-day program, logs of the various activities 
would be collected, permitting a correlation between the activities 
occurring and the sound levels recorded. For all construction 
activities, sound level monitoring stations would consist of bottom 
deployed autonomous recorders at ranges of 500, 1,000 and 1,500 m, 
perpendicular to the construction spread's direction of travel when 
applicable. In addition a cabled recording system would be deployed 
from the appropriate vessel in order to capture close range data 
suitable for determining a source level estimate. The distances and 
directions of any of these sound monitoring locations from the activity 
may be changed if, in the opinion of either Port Dolphin or the marine 
construction contractors, activities at the planned monitoring 
locations could pose health and safety risks or impede vessels or 
construction. If the locations must be changed, the

[[Page 55670]]

monitoring would occur at the safest location that is closest to the 
proposed location that would not interfere with vessels or 
construction. Specific details of monitoring locations for each 
activity type are discussed in the next paragraph.
    For dredging, Port Dolphin is planning to monitor the operation at 
either the exit or entry pit dredges of the western Gulfstream HDD. The 
proposed HDD locations are drilling from land to water at the Port 
Manatee shore approach and from water-to-water at two crossings of the 
Gulfstream pipeline. Port Dolphin is planning to monitor the HDD 
operations at the entry pit of the western Gulfstream HDD. For the 
pipeline laying, plowing and backfilling the pipeline trench, Port 
Dolphin plans to conduct the sound level verification in the Sarasota 
Bay Estuarine System. During these activities, the construction spread 
would be moving relative to the acoustic monitoring stations. This 
would provide a more detailed record of data on received sounds levels 
as a function of range and direction from the construction spread.
    The commissioning of a new SRV type (i.e., different cargo 
containment capacity) at the port may involve the unloading of more 
than one shipment of LNG through the port. The sound level verification 
program is planned to be implemented only once for each new SRV type 
during the approach, unloading, and departure during the first 
commissioning shipment. Once the SRV completes its approach to Port 
Dolphin and is within approximately 5.6 km of the Port, bow and stern 
thrusters would be utilized. Thruster use would vary, operating for 10 
to 30 minutes to allow for the proper positioning of the vessel and 
allow for connection to the STL buoy. Docking or berthing is expected 
to occur at alternate STL buoys approximately every 8 days. The 
monitoring program would consist of a similar combination of autonomous 
and cabled acoustic recorders as outlined here.
    For SRV maneuvering (i.e., approach, docking, unloading, undocking 
and departure) operations, Port Dolphin would establish four sound 
level measuring stations. As part of the DWPL issued by the MarAd, a 
safety zone, an area to be avoided (ATBA), and a no-anchoring zone have 
been established around the deepwater port. The boundary of the safety 
zone has been set at a distance of 850 m (2,790 ft) from both the 
northern and southern STL buoys. The boundaries of both the ATBA and 
no-anchoring zone have been set at 1,500 m (4,925 ft) from both the 
northern and southern STL buoy.
    For the SRV maneuvering to docking/undocking at and departure from 
the two STL buoys, the sound level verification measurements would be 
taken at the boundary of the ATBA. Three bottom-deployed autonomous 
recording stations would therefore be set at a distance of 1,500 m from 
the STL buoys. This would ensure that sufficient data is collected 
regardless of the SRV's specific approach to the STL buoy. In addition, 
a fourth autonomous system would be deployed on a platform directly 
below the STL buoy. The recording system used here would have a 
frequency response of 1 dB from 10 Hz to 20,000 Hz over the 
anticipated measurement range of 100 dB to 220 dB (linear peak re: 1 
[mu]Pa) due to the lower frequencies expected.

Visual Monitoring

    Visual monitoring of relevant zones would be conducted as described 
previously (see `Proposed Mitigation'). Shutdown or delay of activities 
would occur as appropriate. The monitoring biologists would document 
all marine mammals observed in the monitoring area. Data collection 
would include a count of all marine mammals observed by species, sex, 
age class, their location within the zone, and their reaction (if any) 
to construction activities, including direction of movement, and type 
of construction that is occurring, time that activity begins and ends, 
any acoustic or visual disturbance, and time of the observation. 
Environmental conditions such as wind speed, wind direction, 
visibility, and temperature would also be recorded. No monitoring would 
be conducted during inclement weather that creates potentially 
hazardous conditions, as determined by the PSO(s). No monitoring would 
be conducted when visibility is significantly limited, such as during 
heavy rain or fog. During these times of inclement weather, in-water 
work that may produce sound levels in excess of 180 dB rms may 
continue, but may not be started. Impact pile driving shall not occur 
when visibility is significantly limited.
    All monitoring personnel must have appropriate qualifications as 
identified previously. These qualifications include education and 
experience identifying marine mammals and the ability to understand and 
document marine mammal behavior. All monitoring personnel would meet at 
least once for a training session provided by Port Dolphin, and Port 
Dolphin would be responsible for verifying to NMFS that PSOs meet the 
minimal qualifications described previously. Topics would include, at 
minimum, implementation of the monitoring protocol, identification of 
marine mammals, and reporting requirements. All monitoring personnel 
would be provided a copy of the LOA. Monitoring personnel must read and 
understand the contents of the LOA as they relate to coordination, 
communication, and identifying and reporting incidental harassment of 
marine mammals. All sightings must be recorded on approved marine 
mammal field sighting logs.

Proposed Reporting

    Reports of data collected during monitoring would be submitted to 
NMFS weekly. In addition, a final report summarizing all marine mammal 
monitoring and construction activities would be submitted to NMFS 
annually. The report would include:
     All data described previously under monitoring, including 
observation dates, times, and conditions; and
     Correlations of observed behavior with activity type and 
received levels of sound, to the extent possible.
    Port Dolphin would also submit a report(s), as necessary, 
concerning the results of all acoustic monitoring. The final report for 
acoustic monitoring of construction activities would be provided at the 
completion of all marine construction activities. Reporting for 
acoustic monitoring of operational activities would be provided at the 
completion of the commissioning period for each new SRV servicing the 
port. Port Dolphin would to submit these reports to NMFS within 60 
working days of the completion of each monitoring event.
    Acoustic monitoring reports would include:
     A detailed description of the monitoring protocol;
     A description of the sound monitoring equipment;
     Documentation of calibration activities;
     The depth of water at the hydrophone locations and the 
depth of the hydrophones;
     The background SPL reported as the 50 percent cumulative 
density function;
     A summary of the data recorded during monitoring; and
     Analysis of the recorded data and conclusions.
    Analysis of the data should include the frequency spectrum, ranges 
and means including the standard deviation/error for the peak and rms 
SPLs, and an estimation of the distance at which rms values reach the 
relevant marine mammal thresholds and background sound levels. 
Vibratory driving results

[[Page 55671]]

would include the maximum and overall average rms calculated from 30-s 
rms values during driving of the pile. In addition, for pile driving, 
the report would include:
     Size and type of any piles driven, correlated with SPLs;
     A detailed description of any sound attenuation device 
used, including design specifications;
     The impact hammer energy rating used to drive the piles, 
make and model of the hammer(s), and description of the vibratory 
hammer;
     The physical characteristics of the bottom substrate into 
which the piles were driven; and
     The total number of strikes to drive each pile.
    During all phases of construction activities and operation, 
sightings of any injured or dead marine mammals will be reported 
immediately (except as described later in this section) to the NMFS 
Southeast Region Marine Mammal Stranding Network, regardless of whether 
the injury or death is caused by project activities. In addition, if a 
marine mammal is struck by a project vessel (e.g., SRV, support 
vessel), or in the unanticipated event that project activity clearly 
resulted in the injury, serious injury, or death (e.g., gear 
interaction, and/or entanglement) of a marine mammal, USCG and NMFS 
must be notified immediately, and a full report must be provided to 
NMFS, Southeast Regional Office, and NMFS, Office of Protected 
Resources. The report must include the following information: (1) The 
time, date, and location (latitude/longitude) of the incident; (2) the 
name and type of vessel involved, if applicable; (3) the vessel's speed 
during and leading up to the incident, if applicable; (4) a description 
of the incident; (5) water depth; (6) environmental conditions (e.g., 
wind speed and direction, sea state, cloud cover, visibility); (7) the 
species identification or description of the animal(s) involved; (8) 
the fate of the animal(s); and (9) photographs or video footage of the 
animal (if equipment is available). Following such an incident, 
activities must cease until NMFS is able to review the circumstances of 
the incident. NMFS would work with Port Dolphin to determine what is 
necessary to minimize the likelihood of further prohibited take and 
ensure MMPA compliance. Port Dolphin may not resume activity until 
notified to do so by NMFS. If a prohibited take should occur, the NMFS 
Office of Law Enforcement and the Florida Fish and Wildlife 
Conservation Commission law enforcement would be notified.
    In the event that an injured or dead marine mammal is discovered, 
and the lead PSO determines that the cause of the injury or death is 
unknown and the death is relatively recent (i.e., in less than a 
moderate state of decomposition as described in the next paragraph), 
Port Dolphin will immediately report the incident to NMFS, Office of 
Protected Resources. The report must include the same information 
identified in the preceding paragraph. However, activity may continue 
while NMFS reviews the circumstances of the incident, and NMFS will 
work with Port Dolphin to determine whether modifications to the 
activities are appropriate. If the lead PSO determines that the 
discovered animal is not associated with or related to project 
activities (e.g., previously wounded animal, carcass with moderate to 
advanced decomposition, scavenger damage), Port Dolphin would report 
the incident to NMFS, Office of Protected Resources, within 24 hours of 
the discovery. Port Dolphin should provide photographs or video footage 
(if available) or other documentation of the sighting. Activities may 
continue while NMFS reviews the circumstances of the incident.
    An annual report on marine mammal monitoring and mitigation would 
be submitted to NMFS, Office of Protected Resources, and NMFS, 
Southeast Regional Office, each year. The weekly and annual reports 
would include data collected for each distinct marine mammal species 
observed in the project area. Description of marine mammal behavior, 
overall numbers of individuals observed, frequency of observation, and 
any behavioral changes and the context of the changes relative to 
activities would also be included in the annual reports. Additional 
information that would be recorded during activities and contained in 
the reports include: date and time of marine mammal detections, weather 
conditions, species identification, approximate distance from the 
source, and activity at the construction site when a marine mammal is 
sighted.
    In addition to annual reports, Port Dolphin would submit a draft 
comprehensive final report to NMFS, Office of Protected Resources, and 
NMFS, Southeast Regional Office, 180 days prior to the expiration of 
the regulations. This comprehensive technical report would provide full 
documentation of methods, results, and interpretation of all monitoring 
during the first 4.5 years of the regulations. A revised final 
comprehensive technical report, including all monitoring results during 
the entire period of the regulations would be due 90 days after the end 
of the period of effectiveness of the regulations.

Adaptive Management

    The final regulations governing the take of marine mammals 
incidental to the specified activities at Port Dolphin would contain an 
adaptive management component. In accordance with 50 CFR 216.105(c), 
regulations for the proposed activity must be based on the best 
available information. As new information is developed, through 
monitoring, reporting, or research, the regulations may be modified, in 
whole or in part, after notice and opportunity for public review. The 
use of adaptive management would allow NMFS to consider new information 
from different sources to determine if mitigation or monitoring 
measures should be modified (including additions or deletions) if new 
data suggest that such modifications are appropriate for subsequent 
LOAs.
    The following are some of the possible sources of applicable data:
     Results from Port Dolphin's monitoring from the previous 
year;
     Results from general marine mammal and acoustics research; 
or
     Any information which reveals that marine mammals may have 
been taken in a manner, extent or number not authorized by these 
regulations or subsequent LOAs.
    If, during the effective dates of the regulations, new information 
is presented from monitoring, reporting, or research, these regulations 
may be modified, in whole, or in part after notice and opportunity of 
public review, as allowed for in 50 CFR 216.105(c). In addition, LOAs 
would be withdrawn or suspended if, after notice and opportunity for 
public comment, the Assistant Administrator finds, among other things, 
that the regulations are not being substantially complied with or that 
the taking allowed is having more than a negligible impact on the 
species or stock, as allowed for in 50 CFR 216.106(e). That is, should 
substantial changes in marine mammal populations in the project area 
occur or monitoring and reporting show that Port Dolphin actions are 
having more than a negligible impact on marine mammals, then NMFS 
reserves the right to modify the regulations and/or withdraw or suspend 
LOAs after public review.

Estimated Take by Incidental Harassment

    Except with respect to certain activities not pertinent here, the 
MMPA defines ``harassment'' as: ``any act of pursuit, torment, or 
annoyance which (i) has the potential to injure a marine

[[Page 55672]]

mammal or marine mammal stock in the wild [Level A harassment]; or (ii) 
has the potential to disturb a marine mammal or marine mammal stock in 
the wild by causing disruption of behavioral patterns, including, but 
not limited to, migration, breathing, nursing, breeding, feeding, or 
sheltering [Level B harassment].'' Take by Level B harassment only is 
anticipated as a result of Port Dolphin's proposed activities. Take of 
marine mammals is anticipated to occur as a result of elevated levels 
of sound from the previously described activities associated with 
construction and installation of the port and from port operations. No 
take by injury, serious injury, or death is anticipated.
    As described previously in the ``Distance to Sound Thresholds'' 
section of this document, JASCO Research modeled a series of scenarios 
that thoroughly characterize the various construction/installation and 
operation activities expected. JASCO used proxy sound sources selected 
from a database of underwater sound measurements. The selected proxy 
sound sources were input to a sound propagation model with multiple 
parameters, including expected water column sound speeds, bathymetry, 
and bottom geoacoustic properties, to estimate the radii of sound 
impacts (JASCO, 2008, 2010). Note that for some scenarios, 180-dB 
threshold values only occur in the immediate vicinity of individual 
pieces of equipment that combine to form a construction ``spread,'' or 
modeled scenario, with little or no overlap of the sound fields from 
neighboring vessels. These scenarios are for transient activities--for 
example, pipelaying and burial activities require a spread of vessels 
and equipment (e.g., barges, tugs) rather than a single point source of 
sound. These modeled scenarios combine the sound output from multiple 
vessels/pieces of equipment. The overall radius depends primarily on 
the spacing between the vessels, and a single scenario-specific radius 
for the 180-dB threshold cannot sensibly be defined. All activity types 
considered here would produce sound source levels attenuating to less 
than 180 dB within 200 m; thus, 200 m is used as a conservative 
estimator for 180-dB area calculations in most cases.
    JASCO's modeling reports the radial distance from each modeled 
source to received levels in 10 dB increments (i.e., from 120 dB 
through 180 dB), and this information is used here to report the 
intensity of sound source levels relative to this 200 m radius in 
subsequent sections. Please see Appendices C and D in Port Dolphin's 
application for a detailed description of this sound source modeling 
and Appendix E for a graphical depiction of the sound fields from 
various activities. Results of the modeled underwater analysis for Port 
Dolphin construction and operation are summarized as follows:
     Buoy installation: Installation of the buoys at the Port 
would produce continuous, transient (non-pulsed) sound for a relatively 
short period of time during summer, with 120-dB isopleths located 3.9 
km from each STL buoy location and corresponding ensonification of 
approximately 48 km\2\. At 200 m distance, sound produced by buoy 
installation would attenuate to less than 150 dB.
     Pipelaying: Pipelaying activities would generate 
continuous (non-pulsed) sound, and would be transient as the pipelaying 
operation moved along the pipeline route. Construction is expected to 
occur during summer and fall. Depending on location, the 120[hyphen]dB 
isopleth for pipelaying activities would extend either 6.0 (offshore) 
or 7.5 km (inshore) from the source, encompassing approximately 113 or 
178 km\2\, respectively. At 200 m distance, sound produced by 
pipelaying would attenuate to less than 160 dB.
     Pipeline burial: Pipeline burial using the plow system 
would generate continuous, transient sound during construction similar 
to pipelaying and is expected to occur during fall and winter. Pipeline 
burial would only be used in those locations with suitable substrate 
conditions. Distances to the 120[hyphen]dB isopleth would be 6.7 
(offshore) or 8.4 km (inshore) from the source and would encompass 
approximately 141 or 222 km\2\. At 200 m distance, sound produced by 
pipeline burial would attenuate to less than 160 dB.
     Pile driving: Offshore installation of anchors via impact 
pile driving is slated to occur during summer. This impulsive sound 
source would produce a 160-dB isopleth at 4.5 km from each STL buoy 
location, encompassing approximately 64 km\2\. The 180-dB isopleths 
would extend to 180 m from the source, encompassing approximately 0.1 
km\2\.
     HDD: Horizontal directional drilling within Tampa Bay 
would produce continuous, non-pulsed sound and is expected to occur 
during summer. The 120-dB isopleth would extend 240 m from the drilling 
operation, encompassing approximately 0.2 km\2\. Calculations based on 
the area of ensonification for HDD indicate that no marine mammals 
would be harassed as a result of this activity. Source levels for this 
activity are expected to be below the 180-dB threshold; therefore, 
consideration of Level A harassment is not relevant.
     HDD vibratory driving: Installation of the goal posts at 
each HDD location would produce continuous, non-pulsed sound for a 
relatively short period of time, exclusively during summer. The 120-dB 
isopleth for HDD vibratory driving would extend 12.6 km from the 
source, encompassing approximately 499 km\2\. The 180-dB isopleths 
would be less than 10 m from the source.
     SRV maneuvering: Once an SRV completes its approach to 
Port Dolphin and is within approximately 5.6 km of the port, bow and 
stern thrusters would be utilized. Thruster use would vary, operating 
for 10 to 30 minutes to allow for the proper positioning of the vessel 
and connection to the STL buoy. Docking or berthing would occur at 
alternate STL buoys approximately every 8 days. The periodic use of the 
thrusters would produce continuous, non-pulsed sound that would be 
transient as the vessel moves, with the 120-dB isopleth occurring at 
3.6 km from the SRV, encompassing approximately 41 km\2\. The 180-dB 
isopleths would be less than 10 m from the source.
     Regasification: SRVs would regasify LNG cargo while docked 
at a STL buoy, producing continuous, non-pulsed sound. Sound levels for 
regasification are low, with the 120-dB isopleth at 170 m from the 
source, encompassing approximately 0.09 km\2\. Calculations based on 
this area of ensonification indicate that no marine mammals would be 
harassed as a result of this activity. Source levels for this activity 
are below the 180-dB threshold.
    Density of marine mammals in the project area was derived from a 
U.S. Navy review of available marine mammal survey data for the eastern 
Gulf of Mexico which summarized species presence and distribution on a 
seasonal basis (USDON, 2003). As described previously, marine mammal 
densities are determined on the basis of both seasonality and depth 
stratum. While the area of actual construction and operations for Port 
Dolphin is entirely contained within the nearshore depth stratum (0 to 
37 m), the sound field from certain construction activity, and thus the 
area of effect, extends into the mid-shelf depth stratum (37 to 91 m). 
This has implications for the species of marine mammals that may 
potentially be affected by the activity. Almost all sound produced by 
construction activities would occur within the nearshore stratum. The 
only activity with a sound field extending to the mid-shelf depth 
stratum is offshore pipelaying, which would occur only

[[Page 55673]]

during construction, from approximately late summer 2013 through early 
winter 2013-14. The Level B sound field for this activity would be 99.9 
percent contained within the nearshore stratum, with 0.1 percent 
projected to enter the mid-shelf stratum. Densities for marine mammals 
that may be affected by the proposed activities are presented in Table 
8.

     Table 8--Density Estimates for Marine Mammals in the Nearshore and Mid-Shelf Depth Strata, Eastern GOM
----------------------------------------------------------------------------------------------------------------
                                                            Density (Individuals/100 km\2\ (39 mi\2\))
                     Species                     ---------------------------------------------------------------
                                                      Winter          Spring          Summer           Fall
----------------------------------------------------------------------------------------------------------------
Nearshore depth stratum:
    Atlantic spotted dolphin....................           2.243          10.752           2.524          10.752
    Bottlenose dolphin..........................          10.913          21.986           8.241          26.744
Mid-shelf depth stratum:
    Atlantic spotted dolphin....................          11.630          21.699          17.354          22.916
    Bottlenose dolphin..........................           7.410           2.588          11.707          10.856
    Dwarf/pygmy sperm whale.....................           0.000           0.011           0.011           0.000
    Rough-toothed dolphin.......................           0.000           0.000           0.000           0.400
----------------------------------------------------------------------------------------------------------------
Source: USDON, 2003.

    Incidental take estimates are calculated based on: (1) The number 
of marine mammals that occur within each respective depth stratum, 
using species- and season-specific density estimates; (2) the 
percentage of sound field within each depth stratum, by source (this is 
relevant for offshore pipelaying only); (3) the areal extent of Level A 
and Level B sound fields, by sound source; and (4) the time or distance 
component of the activity. Areas of ensonification, by appropriate 
threshold, are presented in Table 6. With regard to the fourth 
component (time/distance), there are two types of construction 
activities: stationary and transient. Stationary activities would occur 
near specific sites (e.g., locations for buoy installation), while 
transient activities would occur while traveling along a pre-determined 
trackline (i.e., the pipeline route). Incidental take associated with 
stationary activities is determined by considering the estimated number 
of days of effect. Buoy installation, impact pile driving, and 
vibratory pile driving activities are expected to take 6, 32, and 8 
days, respectively. The pre-determined pipeline route along which the 
pipelaying and burial activities would occur is approximately 72 km 
long (37 km offshore, 35 km inshore). For these transient activities, 
the overall area of effect (i.e., distance x width of ensonified area) 
is used in calculating estimated incidental take.
    For stationary activities, season-specific estimated take was 
determined by first multiplying the modeled ZOI (i.e., the area 
ensonified using the appropriate thresholds) and the appropriate 
species-specific seasonal densities within each depth stratum (USDON, 
2003). These results were then rounded to the nearest whole number and 
multiplied by the estimated number of days of effect to provide an 
estimate of take.
    For transient activities, season-specific estimated take was 
determined by multiplying the overall area of effect for offshore and 
inshore portions, respectively, by the appropriate density and, because 
some of these activities are expected to occur during multiple seasons, 
by the proportion of trackline expected to be completed during a given 
season. For offshore pipelaying, approximately 43 percent of effort is 
expected to occur during summer and 57 percent occur during fall. The 
inshore portion would occur entirely during fall. For offshore pipe 
burial, approximately 12 percent of effort is expected to occur during 
fall and 88 percent occurring during winter. The inshore portion would 
occur entirely during winter.
    For offshore pipelaying, the estimated take within each depth 
stratum was then integrated into the seasonal, species-specific 
calculations. Calculations indicate that, on the basis of the densities 
shown in Table 8 and the 0.1 percent of the sound field for pipelaying 
that would occur in the mid-shelf depth stratum, no incidental take of 
dwarf/pygmy sperm whales (i.e., Kogia spp.) or rough-toothed dolphins 
would occur. Similarly, take of spotted and bottlenose dolphins would 
occur only in the nearshore depth stratum (i.e., the 0.1 percent of 
effect occurring in the mid-shelf depth stratum would not add to the 
total take). Dwarf/pygmy sperm whales and rough-toothed dolphins are 
not covered by this proposed rule because incidental take is not 
anticipated, and no incidental take is proposed to be authorized. The 
results of take estimation calculations for bottlenose dolphins and 
spotted dolphins for construction activities are shown in Table 9.

                           Table 9--Estimated Incidental Take, Construction Activities
----------------------------------------------------------------------------------------------------------------
                                                                                              Species
                                                                                 -------------------------------
                   Activity                                  Season                  Atlantic
                                                                                      spotted       Bottlenose
                                                                                      dolphin         dolphin
----------------------------------------------------------------------------------------------------------------
Buoy installation............................  Summer...........................               6              24
Impact pile driving..........................  Summer...........................              64             160
Pipelaying--Offshore.........................  Summer...........................               6              20
                                               Fall.............................              34              85
Pipelaying--Inshore..........................  Fall.............................              45             112
Pipeline burial--Offshore....................  Fall.............................               8              20
                                               Winter...........................              12              60
Pipeline burial--Inshore.....................  Winter...........................              11              51

[[Page 55674]]

 
Vibratory pile driving.......................  Summer...........................             104             328
                                                                                 -------------------------------
    Total, by species........................  .................................             290             860
----------------------------------------------------------------------------------------------------------------

    When the Port reaches operational status, an estimated 46 SRV 
visits would occur per year. Visits would be equally distributed across 
seasons, with 12 visits expected during winter and summer seasons and 
11 visits per season during spring and fall. Each visit includes 
arrival and departure of the SRV, so 46 visits would result in 92 
episodes that may result in incidental take. The results of take 
estimation calculations for operational activities, for a given year, 
are shown in Table 10.

                                               Table 10--Estimated Yearly Incidental Take, Port Operations
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                             Atlantic spotted dolphin           Bottlenose dolphin
                                                                                         ---------------------------------------------------------------
                 Activity                              Season                  Trips       Single visit                    Single visit
                                                                                                \1\          Seasonal           \1\          Seasonal
--------------------------------------------------------------------------------------------------------------------------------------------------------
SRV maneuvering..........................  Summer.......................              12               2              24               7              84
                                           Fall.........................              11               9              99              22             242
                                           Winter.......................              12               2              24               9             108
                                           Spring.......................              11               9              99              18             198
                                                                         -------------------------------------------------------------------------------
    Totals \2\...........................  .............................              46  ..............             246  ..............             632
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Single-visit take calculated by multiplying appropriate density and appropriate area, then doubling the result to account for arrival and departure
  of the SRV in a single trip.
\2\ Total represents the single visit take multiplied by the total number of trips.

    Assuming that this proposed rulemaking would be in effect during 1 
year of construction and 4 years of operations, the total estimated 
taking, by Level B harassment only, would be 1,274 Atlantic spotted 
dolphins and 3,388 bottlenose dolphins.

Negligible Impact and Small Numbers Analysis and Preliminary 
Determination

    NMFS has defined ``negligible impact'' in 50 CFR 216 as ``* * * an 
impact resulting from the specified activity that cannot be reasonably 
expected to, and is not reasonably likely to, adversely affect the 
species or stock through effects on annual rates of recruitment or 
survival.'' In making a negligible impact determination, NMFS considers 
a variety of factors, including but not limited to: (1) The number of 
anticipated mortalities; (2) the number and nature of anticipated 
injuries; (3) the number, nature, intensity, and duration of Level B 
harassment; and (4) the context in which the takes occur.
    Incidental take, in the form of Level B harassment only, is likely 
to occur primarily as a result of marine mammal exposure to elevated 
levels of sound resulting from the specified activities. No take by 
injury, serious injury, or death is anticipated or proposed for 
authorization. The expected impacts from this activity would be Level B 
harassment in the form of behavioral disturbance resulting in, for 
example, changed direction or speed, or temporary avoidance of an area. 
Anticipated behavioral disturbance is likely to be of low intensity due 
to the sound source characteristics--the majority of activities 
considered here would produce low source levels of non-pulsed sound 
that would be either intermittent or transient--and relatively short in 
duration associated with the specified activities. For the same 
reasons, no individual marine mammals are expected to incur any hearing 
impairment, whether temporary or permanent in nature. That is, non-
pulsed sound does not produce the rapid rise times that are more likely 
to produce hearing impairment in marine mammals, and the low intensity 
of the sources would result in Level A isopleths within a short 
distance. Several activities would produce source levels below those 
considered capable of causing hearing impairment, even in close 
proximity to marine mammals. The shutdown zone monitoring proposed as 
mitigation, and the small size of the zones in which injury may occur, 
further reduces the potential for any injury of marine mammals, making 
the possibility of hearing impairment extremely unlikely and therefore 
discountable.
    For the greater portion of the life of this proposed rule (i.e., 4 
years remaining after the first year of construction), only port 
operations would occur. Each episode of SRV arrival/departure 
(requiring thruster use for a period of several hours) would be 
separated by approximately 8 days of regasification, an activity not 
expected to result in incidental take. The likely effects of behavioral 
disturbance from port operations are minor, as many animals perform 
vital functions, such as feeding, resting, traveling, and socializing, 
on a diel (24-hour) cycle. Behavioral reactions to sound exposure (such 
as disruption of critical life functions, displacement, or avoidance of 
important habitat) are more likely to be significant if they last more 
than one diel cycle or recur on subsequent days (Southall et al., 
2007). Operational activities would occur on a single day (i.e., 
arrival or departure of a SRV), would not recur for a period of 8 days, 
and, as for the majority of construction activities, would produce only 
low levels of non-pulsed sound. NMFS' current criterion for Level B 
harassment from non-pulsed, underwater sound levels (the vast majority 
of sound produced by the proposed activities) is 120 dB rms. However, 
not all marine mammals react to sounds at this low level, and many will 
not show strong reactions (and in some cases any

[[Page 55675]]

reaction) until sounds are much stronger.
    Neither the bottlenose dolphin nor spotted dolphin is listed under 
the ESA. However, NMFS considers the bay, sound, and estuarine stock of 
bottlenose dolphins (of which the Tampa Bay/Sarasota Bay populations 
are a component) to be strategic under the MMPA. NMFS is in the process 
of writing individual stock assessment reports for each of the 32 bay, 
sound and estuary stocks of bottlenose dolphins, but none has been 
completed for the Tampa Bay/Sarasota Bay populations. There is 
insufficient data to determine population trends or status of the 
relevant stocks relative to optimum sustainable population. Population 
estimates for these species were provided earlier in this document (see 
the ``Description of Marine Mammals in the Area of the Specified 
Activity'' section).
    The maximum estimated take per year of Atlantic spotted dolphins 
(290) would be small relative to the stock size (37,611; 0.1 percent); 
this would decline for subsequent years of operations. As a result, 
only small numbers of Atlantic spotted dolphins would be taken. For 
bottlenose dolphins, the maximum estimated total take per year for all 
bottlenose dolphins (860) is small relative to the coastal stock size 
(7,702; 11 percent); this would decline for subsequent years of 
operations. As a result, only small numbers of bottlenose dolphins from 
the coastal stock could be taken. However, it is difficult to partition 
potential takings between the coastal stock (7,702) and the smaller 
bay, sound, and estuarine stock (719) because the possibility for 
mixing of the stocks precludes any quantitative understanding of how 
the total estimated taking might be apportioned between stocks.
    Although it is not possible to predict that portion of overall 
incidental take that might accrue to bay dolphin populations, NMFS 
believes that the potential effects of the proposed activities 
represent a negligible impact for bay dolphins. Only a subset of the 
specified activities has the potential to affect bay dolphins. Buoy 
installation and impact pile driving, as well as the entire offshore 
portion of pipelaying and burial, would occur offshore and would not 
have the potential to affect the bay dolphin populations. Vibratory 
pile driving would occur entirely within Tampa Bay, as would a portion 
of inshore pipelaying and burial, and could impact the bay populations. 
Vibratory pile driving would occur for only 8 days (at two piles per 
day), meaning that any harassment experienced by bay dolphins from this 
activity would be of very short duration. In addition, Tampa Bay is 
significantly industrialized and urbanized and is heavily used by 
recreational boaters. Bottlenose dolphins occurring in Tampa Bay are 
somewhat acclimated to disturbance and would not be expected to 
experience significant disruption to behavioral patterns on the basis 
of short-term and low intensity disturbance, such as is proposed for 
this project. The proposed activities would not take place in areas 
known to be of special significance for feeding or breeding.
    In summary, NMFS believes that potential impacts to bay dolphins 
represent a negligible impact for the following reasons: (1) Only a 
subset of project activities have the potential to affect bay dolphins; 
(2) any takes would be of low intensity (resulting from exposure to low 
levels of non-pulsed sound over a limited duration) and likely would 
not result in significant alteration of dolphin behavior in the heavily 
urbanized/industrialized area where the activity would occur; (3) any 
takes are likely to represent repeated takes of individuals using the 
area where the activity is occurring, rather than each take being of a 
new individual; and (4) an unknown, but possibly large, number of 
coastal stock dolphins may be mixing in inshore waters at any given 
time, and it is not possible to accurately determine how many of the 
takes may occur to individuals of the coastal stock versus individuals 
of the bay stock. Finally, following the initial year of construction, 
all operations would occur offshore, and there would be no potential 
for incidental take of bay dolphins.
    Based on the analysis contained herein of the likely effects of the 
specified activity on marine mammals and their habitat, and taking into 
consideration the implementation of the mitigation and monitoring 
measures, NMFS preliminarily finds that construction and operation of 
Port Dolphin would result in the incidental take of small numbers of 
marine mammals, by Level B harassment only, and that the total taking 
from Port Dolphin's proposed activities would have a negligible impact 
on the affected species or stocks.

Impact on Availability of Affected Species or Stock for Taking for 
Subsistence Uses

    There are no relevant subsistence uses of marine mammals implicated 
by this action.

Endangered Species Act (ESA)

    On August 4, 2009, NMFS concluded consultation with MarAd and USCG 
under section 7 of the ESA on the proposed construction and operation 
of the Port Dolphin LNG facility. The result of that consultation was 
NMFS' concurrence with Port Dolphin's determination that the proposed 
activities may affect, but are not likely to adversely affect, listed 
species under NMFS' jurisdiction. NMFS does not propose to authorize 
incidental take of any ESA-listed marine mammal species. No listed 
species will be impacted by the specified activities.

National Environmental Policy Act (NEPA)

    The USCG and the MarAd initiated the public scoping process in July 
2007, with the publication of a Notice of Intent (NOI) to prepare an 
Environmental Impact Statement (EIS) in the Federal Register. The NOI 
included information on public meetings and informational open houses; 
requested public comments on the scope of the EIS; and provided 
information on how the public could submit comments. A Notice of 
Availability for the Draft EIS was published in the Federal Register in 
April 2008. Subsequently, a final EIS was published in July 2009. MarAd 
issued a Record of Decision (ROD) approving, with conditions, the Port 
Dolphin Energy Deepwater Port License application on October 26, 2009.
    Because NMFS was a cooperating agency in the development of the 
Port Dolphin EIS, NMFS will adopt the EIS and, if appropriate, issue 
its own ROD for issuance of authorizations pursuant to section 
101(a)(5)(A) of the MMPA for the activities proposed by Port Dolphin.

Information Solicited

    NMFS requests interested persons to submit comments, information, 
and suggestions concerning the request and the content of the proposed 
regulations to authorize the taking (see ADDRESSES).

Classification

    The Office of Management and Budget (OMB) has determined that this 
proposed rule is not significant for purposes of Executive Order 12866.
    Pursuant to section 605(b) of the Regulatory Flexibility Act (RFA), 
the Chief Counsel for Regulation of the Department of Commerce has 
certified to the Chief Counsel for Advocacy of the Small Business 
Administration that this proposed rule, if adopted, would not have a 
significant economic impact on a substantial number of small entities. 
Port Dolphin Energy LLC is the only

[[Page 55676]]

entity that would be subject to the requirements in these proposed 
regulations. Port Dolphin is ultimately owned by the Norway-based 
shipping company H[ouml]egh LNG AS, which is itself held by Leif 
H[ouml]egh & Co, a global shipping company. Therefore, it is not a 
small governmental jurisdiction, small organization, or small business, 
as defined by the RFA. Because of this certification, a regulatory 
flexibility analysis is not required, and none has been prepared.
    Notwithstanding any other provision of law, no person is required 
to respond to nor shall a person be subject to a penalty for failure to 
comply with a collection of information subject to the requirements of 
the Paperwork Reduction Act (PRA) unless that collection of information 
displays a currently valid OMB control number. This proposed rule 
contains collection-of-information requirements subject to the 
provisions of the PRA. These requirements have been approved by OMB 
under control number 0648-0151 and include applications for 
regulations, subsequent LOAs, and reports. Send comments regarding any 
aspect of this data collection, including suggestions for reducing the 
burden, to NMFS and the OMB Desk Officer (see ADDRESSES).

List of Subjects in 50 CFR Part 217

    Exports, Fish, Imports, Indians, Labeling, Marine mammals, 
Penalties, Reporting and recordkeeping requirements, Seafood, 
Transportation.

    Dated: September 4, 2012.
Alan D. Risenhoover,
Director, Office of Sustainable Fisheries, performing the functions and 
duties of the Deputy Assistant Administrator for Regulatory Programs, 
National Marine Fisheries Service.

    For reasons set forth in the preamble, 50 CFR part 217 is proposed 
to be amended as follows:

PART 217--REGULATIONS GOVERNING THE TAKE OF MARINE MAMMALS 
INCIDENTAL TO SPECIFIED ACTIVITIES

    1. The authority citation for part 217 continues to read as 
follows:

    Authority: 16 U.S.C. 1361 et seq.

    2. Subpart P is added to part 217 to read as follows:
Subpart P--Taking Marine Mammals Incidental to Construction and 
Operation of a Liquefied Natural Gas Deepwater Port in the Gulf of 
Mexico
Sec.
217.151 Specified activity and specified geographical region.
217.152 Effective dates.
217.153 Permissible methods of taking.
217.154 Prohibitions.
217.155 Mitigation.
217.156 Requirements for monitoring and reporting.
217.157 Letters of Authorization.
217.158 Renewals and Modifications of Letters of Authorization.

Subpart P--Taking Marine Mammals Incidental to Construction and 
Operation of a Liquefied Natural Gas Deepwater Port in the Gulf of 
Mexico


Sec.  217.151  Specified activity and specified geographical region.

    (a) Regulations in this subpart apply only to Port Dolphin Energy 
LLC (Port Dolphin) and those persons it authorizes to conduct 
activities on its behalf for the taking of marine mammals that occurs 
in the area outlined in paragraph (b) of this section and that occur 
incidental to construction and operation of the Port Dolphin Deepwater 
Port (Port).
    (b) The taking of marine mammals by Port Dolphin may be authorized 
in a Letter of Authorization (LOA) only if it occurs in the vicinity of 
the Port Dolphin Deepwater Port in the eastern Gulf of Mexico or along 
the associated pipeline route.


Sec.  217.152  Effective dates.

    [Reserved]


Sec.  217.153  Permissible methods of taking.

    (a) Under LOAs issued pursuant to Sec.  216.106 and Sec.  217.157 
of this chapter, the Holder of the LOA (hereinafter ``Port Dolphin'') 
may incidentally, but not intentionally, take marine mammals within the 
area described in Sec.  217.151(b) of this chapter, provided the 
activity is in compliance with all terms, conditions, and requirements 
of the regulations in this subpart and the appropriate LOA.
    (b) The incidental take of marine mammals under the activities 
identified in Sec.  217.151(a) of this chapter is limited to the 
following species and is limited to Level B Harassment:
    (1) Bottlenose dolphin (Tursiops truncatus)--3,388 (860 the first 
year and an average of 632 annually thereafter)
    (2) Atlantic spotted dolphin (Stenella frontalis)--1,274 (290 the 
first year and an average of 246 annually thereafter)


Sec.  217.154  Prohibitions.

    Notwithstanding takings contemplated in Sec.  217.151 of this 
chapter and authorized by a LOA issued under Sec.  216.106 and Sec.  
217.157 of this chapter, no person in connection with the activities 
described in Sec.  217.151 of this chapter may:
    (a) Take any marine mammal not specified in Sec.  217.153(b) of 
this chapter;
    (b) Take any marine mammal specified in Sec.  217.153(b) of this 
chapter other than by incidental, unintentional Level B Harassment;
    (c) Take a marine mammal specified in Sec.  217.153(b) of this 
chapter if such taking results in more than a negligible impact on the 
species or stocks of such marine mammal; or
    (d) Violate, or fail to comply with, the terms, conditions, and 
requirements of this subpart or a LOA issued under Sec.  216.106 and 
Sec.  217.157 of this chapter.


Sec.  217.155  Mitigation.

    (a) When conducting the activities identified in Sec.  217.151(a) 
of this chapter, the mitigation measures contained in any LOA issued 
under Sec.  216.106 and Sec.  217.157 of this chapter must be 
implemented. These mitigation measures include but are not limited to:
    (1) General Conditions:
    (i) Briefings shall be conducted between the Port Dolphin project 
construction supervisors and the crew, protected species observer(s) 
(PSO), and acoustic monitoring team prior to the start of all 
construction activity, and when new personnel join the work, to explain 
responsibilities, communication procedures, protected species 
monitoring protocol, and operational procedures.
    (ii) Port Dolphin shall comply with all applicable equipment sound 
standards and ensure that all construction equipment has sound control 
devices no less effective than those provided on the original 
equipment. Vessel crew and contractors shall minimize the production of 
underwater sound to the extent possible. Equipment and/or procedures 
used may include the use of enclosures and mufflers on equipment, 
minimizing the use of thrusters, and turning off engines and equipment 
when not in use.
    (iii) All vessels associated with Port Dolphin construction and 
operations shall comply with NMFS Vessel Strike Avoidance Measures and 
Reporting for Mariners and applicable regulations. All vessels 
associated with Port Dolphin construction and operations shall remain 
500 yd (457 m) away from North Atlantic right whales (Eubalaena 
glacialis) and 100 yd (91 m) away from all other marine mammals, except 
in cases where small marine mammals (i.e., delphinids) voluntarily 
approach within 100 yd or unless constrained by human safety concerns 
or navigational constraints.
    (2) Shutdown and Monitoring:
    (i) Shutdown zone: For all activities, shutdown zones shall be 
established. These zones shall include all areas where underwater sound 
pressure levels

[[Page 55677]]

(SPLs) are anticipated to equal or exceed 180 dB re: 1 [mu]Pa rms, as 
determined by modeled scenarios approved by NMFS for each specific 
activity. The actual size of these zones shall be empirically 
determined and reported by Port Dolphin. For all non-stationary 
activities (e.g., pipeline burial, shuttle regasification vessel (SRV) 
maneuvering), Port Dolphin shall maintain a minimum 100 yd (91 m) 
distance from marine mammals, with the exception that voluntary 
approach (e.g., bow riding) within the 100 yd zone by delphinids shall 
not trigger shutdown requirements.
    (ii) Disturbance zone: For all activities, disturbance zones shall 
be established. For impact pile driving, these zones shall include all 
areas where underwater SPLs are anticipated to equal or exceed 160 dB 
re: 1 [mu]Pa rms. For all other activities these zones shall include 
all areas where underwater SPLs are anticipated to equal or exceed 120 
dB re: 1 [mu]Pa rms. These zones shall be established on the basis of 
modeled scenarios approved by NMFS for each specific activity. The 
actual size of disturbance zones shall be empirically determined and 
reported by Port Dolphin, and on-site PSOs shall be aware of the size 
of these zones. However, because of the large size of these zones, 
monitoring of the zone is required only to maximum line-of-sight 
distance from established monitoring locations.
    (iii) Monitoring of shutdown and disturbance zones shall occur for 
all activities. The following measures shall apply:
    (A) Shutdown and disturbance zones shall be monitored from the 
appropriate vessel or work platform, or other suitable vantage point. 
Port Dolphin shall at all times employ, at minimum, two PSOs in 
association with each concurrent specified construction activity.
    (B) The shutdown zone shall be monitored for the presence of marine 
mammals before, during, and after construction activity. For all 
activities, the shutdown zone shall be monitored for 30 minutes prior 
to initiating the start of activity and for 30 minutes following the 
completion of activity. If marine mammals are present within the 
shutdown zone prior to initiating activity, the start shall be delayed 
until the animals leave the shutdown zone of their own volition or 
until 15 minutes has elapsed without observing the animal. If a marine 
mammal is observed within or approaching the shutdown zone, activity 
shall be halted as soon as it is safe to do so, until the animal is 
observed exiting the shutdown zone or 15 minutes has elapsed. If a 
marine mammal is observed within the disturbance zone, a take shall be 
recorded and behaviors documented.
    (C) PSOs shall be on watch at all times during daylight hours when 
in[hyphen]water operations are being conducted, unless conditions 
(e.g., fog, rain, darkness) make observations impossible. If conditions 
deteriorate during daylight hours such that the sea surface 
observations are halted, visual observations must resume as soon as 
conditions permit. While activities will be permitted to continue 
during low-visibility conditions, they (1) must have been initiated 
following proper clearance of the shutdown zone under acceptable 
observation conditions; and (2) must be restarted, if halted for any 
reason, using the appropriate shutdown zone clearance procedures as 
described in Sec.  217.155(a)(2)(iii)(B) of this chapter.
    (3) Pile driving:
    (i) A minimum shutdown zone of 250 m radius shall be established 
around all impact pile driving activity.
    (ii) Contractors shall reduce the power of impact hammers to 
minimum energy levels required to drive a pile.
    (iii) Port Dolphin shall use a sound attenuation measure for impact 
driving of pilings. Prior to beginning construction, Port Dolphin must 
provide information to NMFS about the device to be used, including 
technical specifications. NMFS must approve use of the device before 
construction may begin. If a bubble curtain or similar measure is used, 
it shall distribute small air bubbles around 100 percent of the piling 
perimeter for the full depth of the water column. Any other attenuation 
measure (e.g., temporary sound attenuation pile) must provide 100 
percent coverage in the water column for the full depth of the pile. 
Prior to any impact pile driving, a performance test of the sound 
attenuation device must be conducted in accordance with a NMFS-approved 
acoustic monitoring plan. If a bubble curtain or similar measure is 
utilized, the performance test shall confirm the calculated pressures 
and flow rates at each manifold ring.
    (iv) Ramp-up:
    (A) A ramp-up technique shall be used at the beginning of each 
day's in-water pile driving activities and if pile driving resumes 
after it has ceased for more than 1 hour.
    (B) If a vibratory driver is used, contractors shall be required to 
initiate sound from vibratory hammers for 15 seconds at reduced energy 
followed by a 1-minute waiting period. The procedure shall be repeated 
two additional times before full energy may be achieved.
    (C) If a non-diesel impact hammer is used, contractors shall be 
required to provide an initial set of strikes from the impact hammer at 
reduced energy, followed by a 1-minute waiting period, then two 
subsequent sets.
    (D) If a diesel impact hammer is used, contractors shall be 
required to turn on the sound attenuation device for 15 seconds prior 
to initiating pile driving.
    (v) No impact pile driving shall occur when visibility in the 
shutdown zone is significantly limited, such as during heavy rain or 
fog.
    (4) Additional mitigation measures:
    (i) Use of lights during construction activities shall be limited 
to areas where work is actually occurring, and all other lights must be 
extinguished. Lights must be shielded such that they illuminate the 
deck and do not intentionally illuminate surrounding waters, to the 
extent possible.
    (ii) Additional mitigation measures as contained in a LOA issued 
under Sec.  216.106 and Sec.  217.157 of this chapter.
    (b) [Reserved]


Sec.  217.156  Requirements for monitoring and reporting.

    (a) Visual monitoring program:
    (1) Port Dolphin shall employ, at minimum, two qualified PSOs 
during specified construction-related activities at each site where 
such activities are occurring. All PSOs must be selected in conformance 
with NMFS' minimum qualifications, as described in the preamble to this 
rule, and must receive training sponsored by Port Dolphin, with topics 
to include, at minimum, implementation of the monitoring protocol, 
identification of marine mammals, and reporting requirements. The PSOs 
shall be responsible for visually locating marine mammals in the 
shutdown and disturbance zones and, to the extent possible, identifying 
the species. PSOs shall record, at minimum, the following information:
    (i) A count of all marine mammals observed by species, sex, and age 
class, when possible.
    (ii) Their location within the shutdown or disturbance zone, and 
their reaction (if any) to construction activities, including direction 
of movement.
    (iii) Activity that is occurring at the time of observation, 
including time that activity begins and ends, any acoustic or visual 
disturbance, and time of the observation.
    (iv) Environmental conditions, including wind speed, wind 
direction, visibility, and temperature.
    (2) Port Dolphin shall sponsor a training course to designated crew 
members assigned to vessels associated

[[Page 55678]]

with construction activities or support of operations who will have 
responsibilities for watching for marine mammals. This course shall 
cover topics including, but not limited to, descriptions of the marine 
mammals found in the area, mitigation and monitoring requirements 
contained in a LOA, sighting log requirements, provisions of NMFS 
Vessel Strike Avoidance Measures and Reporting for Mariners, and 
procedures for reporting injured or dead marine mammals.
    (3) Monitoring shall be conducted using appropriate binoculars, 
such as 8x50 marine binoculars. When possible, digital video or still 
cameras shall also be used to document the behavior and response of 
marine mammals to construction activities or other disturbances.
    (4) Each PSO shall have two-way communication capability for 
contact with other PSOs or work crews. PSOs shall implement shut-down 
or delay procedures when applicable by calling for the shut-down to the 
equipment/vessel operator.
    (5) A GPS unit and/or appropriate range finding device shall be 
used for determining the observation location and distance to marine 
mammals, vessels, and construction equipment.
    (6) During arrival and departure of SRVs and regasification, 
qualified PSOs may not be required. During SRV arrival and departure, 
while thrusters are engaged for maneuvering, an additional lookout 
shall be designated to exclusively and continuously monitor for marine 
mammals. All sightings of marine mammals by the designated lookout, 
individuals posted to navigational lookout duties, or any other crew 
member while the SRV is maneuvering or in transit to or from the Port 
shall be immediately reported to the watch officer who shall then alert 
the Master. The SRV must report to Port Dolphin any observations of 
marine mammals while maneuvering with thrusters.
    (b) Acoustic monitoring program:
    (1) Port Dolphin must provide NMFS with an acoustic monitoring plan 
describing the planned measurement of underwater sound pressure levels 
from designated construction and operation activities as well as the 
characterization of site-specific sound propagation. NMFS must approve 
this plan before activities may begin, and acoustic monitoring must be 
conducted in accordance with the plan.
    (2) Port Dolphin shall provide NMFS with empirically measured 
source level data for designated sources of sound associated with Port 
construction and operation activities and shall verify distances to 
relevant sound thresholds. Measurements shall be carefully coordinated 
with sound-producing activities.
    (3) [Reserved]
    (c) Reporting--Port Dolphin must implement the following reporting 
requirements:
    (1) A report of data collected during monitoring shall be submitted 
to NMFS following conclusion of construction activities. Subsequent 
reports concerning Port operations shall be submitted annually. The 
reports shall include:
    (i) All data required to be collected during monitoring, as 
described under 217.156(a) of this chapter, including observation 
dates, times, and conditions;
    (ii) Correlations of observed behavior with activity type and 
received levels of sound, to the extent possible; and
    (iii) Estimations of total incidental take of marine mammals, 
extrapolated from observed incidental take.
    (2) Port Dolphin shall also submit a report(s) concerning the 
results of all acoustic monitoring. Acoustic monitoring reports shall 
include information as described in a NMFS-approved acoustic monitoring 
plan.
    (3) Reporting injured or dead marine mammals:
    (i) In the unanticipated event that the specified activity clearly 
causes the take of a marine mammal in a manner prohibited by a LOA (if 
issued), such as an injury (Level A harassment), serious injury, or 
mortality, Port Dolphin shall immediately cease the specified 
activities and report the incident to the Chief of the Permits and 
Conservation Division, Office of Protected Resources, NMFS, and the 
Southeast Regional Stranding Coordinator, NMFS. The report must include 
the following information:
    (A) Time and date of the incident;
    (B) Description of the incident;
    (C) Environmental conditions (e.g., wind speed and direction, 
Beaufort sea state, cloud cover, and visibility);
    (D) Description of all marine mammal observations in the 24 hours 
preceding the incident;
    (E) Species identification or description of the animal(s) 
involved;
    (F) Fate of the animal(s); and
    (G) Photographs or video footage of the animal(s).
    Activities shall not resume until NMFS is able to review the 
circumstances of the prohibited take. NMFS will work with Port Dolphin 
to determine what measures are necessary to minimize the likelihood of 
further prohibited take and ensure MMPA compliance. Port Dolphin may 
not resume their activities until notified by NMFS.
    (ii) In the event that Port Dolphin discovers an injured or dead 
marine mammal, and the lead PSO determines that the cause of the injury 
or death is unknown and the death is relatively recent (e.g., in less 
than a moderate state of decomposition), Port Dolphin shall immediately 
report the incident to the Chief of the Permits and Conservation 
Division, Office of Protected Resources, NMFS, and the Southeast 
Regional Stranding Coordinator, NMFS. The report must include the same 
information identified in 217.156(b)(3)(i) of this chapter. Activities 
may continue while NMFS reviews the circumstances of the incident. NMFS 
will work with Port Dolphin to determine whether additional mitigation 
measures or modifications to the activities are appropriate.
    (iii) In the event that Port Dolphin discovers an injured or dead 
marine mammal, and the lead PSO determines that the injury or death is 
not associated with or related to the activities authorized in the LOA 
(e.g., previously wounded animal, carcass with moderate to advanced 
decomposition, or scavenger damage), Port Dolphin shall report the 
incident to the Chief of the Permits and Conservation Division, Office 
of Protected Resources, NMFS, and the Southeast Regional Stranding 
Coordinator, NMFS, within 24 hours of the discovery. Port Dolphin shall 
provide photographs or video footage or other documentation of the 
stranded animal sighting to NMFS.
    (4) Annual Reports.
    (i) A report summarizing all marine mammal monitoring and 
construction activities shall be submitted to NMFS, Office of Protected 
Resources, and NMFS, Southeast Regional Office (specific contact 
information to be provided in LOA) following the conclusion of 
construction activities. Thereafter, Port Dolphin shall submit annual 
reports summarizing marine mammal monitoring and operations activities.
    (ii) The annual reports shall include data collected for each 
distinct marine mammal species observed in the project area. 
Description of marine mammal behavior, overall numbers of individuals 
observed, frequency of observation, and any behavioral changes and the 
context of the changes relative to activities shall also be included in 
the reports. Additional information that shall be recorded during 
activities and contained in the reports include: Date and time of 
marine mammal detections, weather conditions, species

[[Page 55679]]

identification, approximate distance from the source, and activity at 
the construction site when a marine mammal is sighted.
    (5) Five-year Comprehensive Report.
    (i) Port Dolphin shall submit a draft comprehensive final report to 
NMFS, Office of Protected Resources, and NMFS, Southeast Regional 
Office (specific contact information to be provided in LOA) 180 days 
prior to the expiration of the regulations. This comprehensive 
technical report shall provide full documentation of methods, results, 
and interpretation of all monitoring during the first 4.5 years of the 
activities conducted under the regulations in this Subpart.
    (ii) Port Dolphin shall submit a revised final comprehensive 
technical report, including all monitoring results during the entire 
period of the LOAs, 90 days after the end of the period of 
effectiveness of the regulations to NMFS, Office of Protected 
Resources, and NMFS, Southeast Regional Office (specific contact 
information to be provided in LOA).


Sec.  217.157  Letters of Authorization.

    (a) To incidentally take marine mammals pursuant to these 
regulations, Port Dolphin must apply for and obtain a LOA.
    (b) A LOA, unless suspended or revoked, may be effective for a 
period of time not to exceed the expiration date of these regulations.
    (c) If an LOA expires prior to the expiration date of these 
regulations, Port Dolphin must apply for and obtain a renewal of the 
LOA.
    (d) In the event of projected changes to the activity or to 
mitigation and monitoring measures required by an LOA, Port Dolphin 
must apply for and obtain a modification of the LOA as described in 
Sec.  217.158 of this chapter.
    (e) The LOA shall set forth:
    (1) Permissible methods of incidental taking;
    (2) Means of effecting the least practicable adverse impact (i.e., 
mitigation) on the species, its habitat, and on the availability of the 
species for subsistence uses; and
    (3) Requirements for monitoring and reporting.
    (f) Issuance of the LOA shall be based on a determination that the 
level of taking will be consistent with the findings made for the total 
taking allowable under these regulations.
    (g) Notice of issuance or denial of a LOA shall be published in the 
Federal Register within 30 days of a determination.


Sec.  217.158  Renewals and modifications of Letters of Authorization.

    (a) A LOA issued under Sec.  216.106 and Sec.  217.157 of this 
chapter for the activity identified in Sec.  217.151(a) of this chapter 
shall be renewed or modified upon request by the applicant, provided 
that: (1) The proposed specified activity and mitigation, monitoring, 
and reporting measures, as well as the anticipated impacts, are the 
same as those described and analyzed for these regulations (excluding 
changes made pursuant to the adaptive management provision in Sec.  
217.158(c)(1) of this chapter), and (2) NMFS determines that the 
mitigation, monitoring, and reporting measures required by the previous 
LOA under these regulations were implemented.
    (b) For LOA modification or renewal requests by the applicant that 
include changes to the activity or the mitigation, monitoring, or 
reporting (excluding changes made pursuant to the adaptive management 
provision in Sec.  217.158(c)(1) of this chapter) that do not change 
the findings made for the regulations or result in no more than a minor 
change in the total estimated number of takes (or distribution by 
species or years), NMFS may publish a notice of proposed LOA in the 
Federal Register, including the associated analysis of the change, and 
solicit public comment before issuing the LOA.
    (c) A LOA issued under Sec.  216.106 and Sec.  217.157 of this 
chapter for the activity identified in Sec.  217.151(a) of this chapter 
may be modified by NMFS under the following circumstances:
    (1) Adaptive Management--NMFS may modify (including augment) the 
existing mitigation, monitoring, or reporting measures (after 
consulting with Port Dolphin regarding the practicability of the 
modifications) if doing so creates a reasonable likelihood of more 
effectively accomplishing the goals of the mitigation and monitoring 
set forth in the preamble for these regulations.
    (i) Possible sources of data that could contribute to the decision 
to modify the mitigation, monitoring, or reporting measures in an LOA:
    (A) Results from Port Dolphin's monitoring from the previous 
year(s).
    (B) Results from other marine mammal and/or sound research or 
studies.
    (C) Any information that reveals marine mammals may have been taken 
in a manner, extent or number not authorized by these regulations or 
subsequent LOAs.
    (ii) If, through adaptive management, the modifications to the 
mitigation, monitoring, or reporting measures are substantial, NMFS 
will publish a notice of proposed LOA in the Federal Register and 
solicit public comment.
    (2) Emergencies--If NMFS determines that an emergency exists that 
poses a significant risk to the well-being of the species or stocks of 
marine mammals specified in Sec.  217.153(b) of this chapter, an LOA 
may be modified without prior notice or opportunity for public comment. 
Notice would be published in the Federal Register within 30 days of the 
action.

[FR Doc. 2012-22092 Filed 9-7-12; 8:45 am]
BILLING CODE 3510-22-P