Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to Conductor Pipe Installation Activities at Harmony Platform in Santa Barbara Channel Offshore of California, 58913-58945 [2014-22758]

Download as PDF Vol. 79 Tuesday, No. 189 September 30, 2014 Part III Department of Commerce tkelley on DSK3SPTVN1PROD with NOTICES3 National Oceanic and Atmospheric Administration Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to Conductor Pipe Installation Activities at Harmony Platform in Santa Barbara Channel Offshore of California; Notice VerDate Sep<11>2014 19:40 Sep 29, 2014 Jkt 232001 PO 00000 Frm 00001 Fmt 4717 Sfmt 4717 E:\FR\FM\30SEN3.SGM 30SEN3 58914 Federal Register / Vol. 79, No. 189 / Tuesday, September 30, 2014 / Notices Background DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration RIN 0648–XD188 Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to Conductor Pipe Installation Activities at Harmony Platform in Santa Barbara Channel Offshore of California National Marine Fisheries Service (NMFS), National Oceanic and Atmospheric Administration (NOAA), Commerce. ACTION: Notice; issuance of an Incidental Take Authorization (ITA). AGENCY: In accordance with the Marine Mammal Protection Act (MMPA) regulations, notification is hereby given that NMFS has issued an Incidental Harassment Authorization (IHA) to the ExxonMobil Production Company (ExxonMobil), a Division of ExxonMobil Corporation, to take marine mammals, by Level B harassment only, incidental to installing six conductor pipes via hydraulic hammer driving at the Harmony Platform, Santa Ynez Production Unit, located in the Santa Barbara Channel offshore of California. DATES: Effective September 17, 2014, through September 16, 2015. ADDRESSES: A copy of the final IHA and application are available by writing to Jolie Harrison, Supervisor, Incidental Take Program, Permits and Conservation Division, Office of Protected Resources, National Marine Fisheries Service, 1315 East-West Highway, Silver Spring, MD 20910, by telephoning the contacts listed here, or by visiting the Internet at: https://www. nmfs.noaa.gov/pr/permits/incidental. htm#applications. NMFS prepared an Environmental Assessment (EA) in accordance with the National Environmental Policy Act (NEPA), which is also available at the same Internet address. NMFS also issued a Biological Opinion under section 7 of the Endangered Species Act (ESA) to evaluate the effects of the conductor pipe installation activities and IHA on marine species listed as threatened and endangered. Documents cited in this notice may be viewed, by appointment, during regular business hours, at the aforementioned address. FOR FURTHER INFORMATION CONTACT: Howard Goldstein or Jolie Harrison, Office of Protected Resources, NMFS, 301–427–8401. SUPPLEMENTARY INFORMATION: tkelley on DSK3SPTVN1PROD with NOTICES3 SUMMARY: VerDate Sep<11>2014 19:40 Sep 29, 2014 Jkt 232001 Sections 101(a)(5)(A) and (D) of the MMPA (16 U.S.C. 1361 et seq.), direct the Secretary of Commerce (Secretary) to allow, upon request, the incidental, but not intentional, taking of small numbers of marine mammals, by United States 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. An authorization for the incidental takings shall be granted if NMFS finds that the taking will have a negligible impact on the species or stock(s), and 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 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 March 3, 2014, NMFS received an application from ExxonMobil for the taking of marine mammals incidental to installing six conductor pipes by hydraulic hammering at the Harmony Platform, Santa Ynez Production Unit, in the Santa Barbara Channel offshore of California. Along with the IHA application, NMFS received an addendum titled ‘‘Assessment of Airborne and Underwater Noise from Pile Driving Activities at the Harmony Platform.’’ NMFS determined that the application was adequate and complete on April 28, 2014. The project’s estimated dates are from mid-September to mid-December 2014, but the planned action could occur PO 00000 Frm 00002 Fmt 4701 Sfmt 4703 anytime within a 12-month period from the effective date of the IHA. Acoustic stimuli (i.e., increased underwater and airborne sound) generated during the conductor pipe installation activities are likely to result in the take of marine mammals. Take, by Level B harassment only, of 32 species of marine mammals is anticipated to result from the activities. Description of the Specified Activity Overview ExxonMobil plans to install six conductor pipes by hydraulic hammering at the Harmony Platform, Santa Ynez Production Unit, in the Santa Barbara Channel offshore of California. Dates and Duration ExxonMobil estimates that the planned conductor pipe installation activities will occur from midSeptember to mid-December 2014, but the planned activities could occur anytime within a 12-month period from the effective date of the planned IHA. Precise scheduling is not presently available due to logistical and regulatory uncertainties. The estimated duration of the planned project is 91 days. Under normal working conditions, the planned project is expected to include approximately 84 days of installation activity on the Harmony Platform bounded by 7 days of project mobilization/demobilization activities. It will take approximately 14 days to install each conductor pipe (6 conductors × 14 days = 84 days). Figure 2–1 of the IHA application includes a timeline of pile-driving activities over the approximate three month duration. Specified Geographic Region Harmony Platform is located in the Santa Barbara Channel, which is approximately 100 km (54 nmi) long and 40 km (21.6 nmi) wide, situated between the Channel Islands and the east-west trending coastline of California. The Santa Barbara Channel is the site of several other producing oil fields, including Ellwood, Summerland, Carpinteria offshore, and Dos Cuadras. The Santa Barbara basin is the prominent feature of the Santa Barbara Channel, with sill depths of approximately 250 m (820.2 ft) and 450 m (1,467.4 ft) at eastern and western entrances, respectively, with shallow (60 m or 196.9 ft) inter-island passages to the south. Harmony Platform’s geographical position is 34° 22′ 35.906″ North, 120° 10′ 04.486″ West, at a water depth of 366 m (1,200.8 ft) on the continental slope below a relatively E:\FR\FM\30SEN3.SGM 30SEN3 Federal Register / Vol. 79, No. 189 / Tuesday, September 30, 2014 / Notices steep (7.5%) descent. The Harmony Platform is 43.5 km (27 miles) southwest of Santa Barbara, California (see Figure 1 of the IHA application). It is 4.7 km (2.5 nmi) from the shelf break, which is typically defined at the 100 m (328.1 ft) isobaths (USGS, 2009). It is 3.3 km (1.8 nmi) from the nearest buffered 200 m (656.2 ft) contour, which has been noted for its association with higher recorded densities of cetacean species (Redfern et al., 2013). It is also located 10 to 15 km (5.4 to 8.1 nmi) north of a common traffic route used by vessels to access the ports of Long Beach and Los Angeles. Figure 1–1 of the IHA application includes the location of the Harmony Platform, general site bathymetry, and Santa Barbara area boundaries. Detailed Description of the Specified Activity tkelley on DSK3SPTVN1PROD with NOTICES3 ExxonMobil plans to install six conductor pipes by hydraulic hammering at Harmony Platform. The conductor pipe installation activities are estimated to occur from mid-September to mid-December 2014, but the action could occur anytime within a 12-month period from the effective date of the IHA. Harmony Platform is located 10 kilometers (km) (5.4 nautical miles [nmi]) off the coast of California, between Point Conception and the City of Santa Barbara. Harmony Platform is one of three offshore platforms in ExxonMobil’s Santa Ynez Production Unit, and is located in the Hondo field (Lease OCS–P 0190) at a water depth of 336 meters (1,200.8 ft). Harmony Platform was installed on June 21, 1989 with the sole purpose of producing crude oil and gas condensate. It began production of crude oil, gas and gas condensate on December 30, 1993. A conductor pipe is installed prior to the commencement of drilling operations for oil and gas wells. It provides protection, stability/structural integrity, and a conduit for drill cuttings and drilling fluid to the platform. It also prevents unconsolidated sediment from caving into the wellbore, and provides structural support for the well loads. Drilling activities are currently ongoing at Harmony Platform utilizing the existing conductors and wells. The platform jacket structure (see Figure 1– 2 of the IHA application) currently has conductors installed in 51 out of 60 slots, as approved by the Bureau of Ocean Energy Management (BOEM, formerly the Minerals Management Service [MMS]) in the original Development Production Plan. Addition of eight straight conductors at the Harmony Platform was approved by the Bureau of Safety and Environmental Enforcement (BSEE) on February 11, 2013 to maintain current production levels from the existing platform. Conductor installation with a hydraulic hammer is consistent with approved development plans, and is the same method that was used to install conductors on all three Santa Ynez Production Unit platforms from 1981 (Hondo) through 1993 (Harmony and Heritage). Pipe-driving the conductors is the only proven installation method that enables management of potential interferences with the existing platform infrastructure that will also reach the target depth. Non-pipe-driving conductor installation methods are not deemed feasible at this time due to increased risk to platform structural integrity, offset well collision, and shallow-hole broaching. The total length of a single conductor pipe is approximately 505 m (1,656.8 ft). Each conductor consists of multiple sections of 66.04 centimeter (cm) (26 inch [in]) diameter steel pipe that will be sequentially welded end-to-end from an upper deck of the platform (see Figure 1–2 of the IHA application), and lowered into the 366 m water column through metal rings (conductor guides) affixed to the jacket structure that orient and guide the conductor. Once the conductor reaches the sediment surface, gravity-based penetration (i.e., the conductor will penetrate the seabed under its own weight) is expected to reach approximately 30 m (98.4 ft) below the seabed. A hydraulic hammer (S–90 IHC) with a manufacturer’s specified energy range of 9 to 90 kiloJoules (kJ) will be located on the drill deck and used to drive the conductor to a target depth of approximately 90 to 100 m (295.3 to 328.1 ft) below the seabed; therefore, only roughly 60 m (196.9 ft) of each 505 m (1,656.8 ft) long conductor pipe will require hydraulic driving. The S–90 IHC 58915 hydraulic hammer will sit on the conductor throughout pile-driving operations, but a ram internal to the hammer will stroke back and forth using hydraulic pressure to impart energy to the conductor. No physical dropping of a weight will be employed to drive the conductor. The S–90 IHC hydraulic hammer has an estimated blow rate of about 46 blows per minute. The portion of a complete conductor that must be actively driven (hammered) into the seafloor consists of 5 to 7 sections, which are sequentially welded end-toend. Setup and welding will take 3.5 to 7.3 hours per section, mostly depending on the type of welding equipment used (e.g., automated welder). Impact hammer pipe-driving will take an estimated 2.5 to 3.3 hours for each section, depending primarily on sediment physical properties, which affect penetration rate. Complete installation of each conductor is estimated at approximately 14 days based on 24-hour (continuous) operations. Table 1–1 of the IHA application presents a summary of driving activities and estimated number of joints [requiring welding] for each conductor pipe). Figure 1–3 of the IHA application shows the estimated time in days for each of these activities that are required to install a single conductor pipe. ExxonMobil conservatively assumes that active hammering will be 3.3 hours, followed by 7.3 hours of hammer downtime (i.e., ‘‘quiet time,’’ a time at which other activities are performed in preparation for the next section of pile) over approximately 53 hours (2.2 days) of the approximately 14 days required to install one conductor pipe. This schedule produces 4.125 days (99 hours) of cumulated hammer driving for all six conductors over the project duration. Figure 1–4 depicts the 3.3 hour pile-drive/7.3 hour downtime cycle for an isolated 24-hour period, showing a maximum of 9.4 hours of hammer driving. In the event that efficiencies produce a 2.5 hour drive/3.5 hour downtime cycle, a maximum of 10 hours of hammer pile-driving could occur in a single 24-hour period. The complete installation of the conductor pipes is estimated at 14 days of continuous operation. TABLE 1—SUMMARY OF CONDUCTOR PIPE INSTALLATION ACTIVITIES AND ASSOCIATED CHARACTERISTICS OF EACH CONDUCTOR PIPE AT HARMONY PLATFORM Estimated number of joints Pile-driving required Conductor pipe activity Pipe length (m) Installation level to sea level ...................................................................... Sea level to seafloor .................................................................................. 49 (160.8 ft) 366 (1,200.8 ft) 4 28 Sfmt 4703 30SEN3 VerDate Sep<11>2014 19:40 Sep 29, 2014 Jkt 232001 PO 00000 Frm 00003 Fmt 4701 E:\FR\FM\30SEN3.SGM No ..................... No ..................... Estimated number of days 3 2 5.6 58916 Federal Register / Vol. 79, No. 189 / Tuesday, September 30, 2014 / Notices TABLE 1—SUMMARY OF CONDUCTOR PIPE INSTALLATION ACTIVITIES AND ASSOCIATED CHARACTERISTICS OF EACH CONDUCTOR PIPE AT HARMONY PLATFORM—Continued Conductor pipe activity Pipe length (m) From 0 to ∼30 m below seafloor ............................................................... From ∼30 m to ∼90 m below seafloor ....................................................... Hammer downtime ..................................................................................... Clean up and completion ........................................................................... Estimated number of joints 30 1 (98.4 ft) 60 (196.9 ft) NA NA 3 5 to 7 NA NA Pile-driving required No ..................... Yes 2 ................. No ..................... No ..................... Estimated number of days 3 0.9 0.69 1.52 3.6 1 Estimated 2 See 3 See range of gravity-based penetration. Figure 1–4 of the IHA application. Figure 1–3 of the IHA application. NMFS provided a detailed description of the planned activities in a previous notice for the proposed IHA (79 FR 36743, June 30, 2014). The activities to be conducted have not changed between the proposed IHA notice and this final notice announcing the issuance of the IHA. For a more detailed description of the authorized action, including site bathymetry and sediment physical characteristics, hydrodynamics and water column physical properties, platform and acoustic source specifications, metrics, characteristics of sound sources, predicted sound levels of impact hammer pile-driving, etc., the reader should refer to the notice of the proposed IHA (79 FR 36743, June 30, 2014), the IHA application, addendum, and associated documents referenced above this section. Comments and Responses A notice of the proposed IHA for ExxonMobil’s conductor pipe installation activities was published in the Federal Register on June 30, 2014 (79 FR 36743). During the 30-day public comment period, NMFS received comments from approximately 4,700 private citizens (as supporters of SierraRise and Sierra Club), Center for Biological Diversity (CBD), California Coastal Commission (CCC), and the Marine Mammal Commission (Commission). The comments are online at: https://www.nmfs.noaa.gov/pr/ permits/incidental/. Following are the substantive comments and NMFS’s responses: MMPA Concerns Comment 1: The Commission states that the densities used to estimate the numbers of takes were derived using two different methods. For humpback, blue, and fin whales, ExxonMobil and NMFS stated that they used densities from Redfern et al. (2013) because those data were derived in the same project area—the Santa Barbara Channel. However, the estimated densities for blue and fin whales in the Federal Register notice do not match the upper boundary of the density contours from Redfern et al. (2013), which are shown in Table 6–3 and 6–4 of ExxonMobil’s IHA application. Those figures indicate that the density should be 0.006 whales/ km2 (not 0.008) for blue whales and 0.0065 whales/km2 (not 0.004) for fin whales. Therefore, the Commission recommends that NMFS revise the density estimates for blue and fin whales to reflect the density information from Redfern et al. (2013). Response: NMFS concurs with the Commission’s recommendation. The densities of blue and fin whales in the IHA application and the notice of the proposed IHA (79 FR 36743, June 30, 2014) are slightly below the upper boundary contours displayed in Redfern et al. (2013). NMFS agrees that the density estimates should be 0.006 for the blue whale and 0.0065 for the fin whale. These minor corrections to the density estimates have only a minor effect on the calculated takes by Level B harassment, as shown in the table below. However, NMFS has increased the authorized takes for fin and blue whales to account for group size. TABLE 2—PROPOSED AND CORRECTED DENSITY ESTIMATES FOR TWO OF THE SPECIES/STOCKS PROPOSED TO BE TAKEN INCIDENTAL TO EXXONMOBIL’S CONDUCTOR PIPE INSTALLATION ACTIVITIES Density estimates from Table 5 of the Federal Register notice of the proposed IHA Species tkelley on DSK3SPTVN1PROD with NOTICES3 Fin whale (Balaenoptera physalus) ......................................... Blue whale (Balaenoptera musculus) ...................................... Comment 2: The Commission states that for the species/stocks that are derived from Redfern et al. (2013), ExxonMobil and NMFS derived density estimates by dividing each species/ stock’s abundance estimate by the area of the Santa Barbara Channel (12,593 km2). The abundance estimates used by NMFS (in Table 5 of the notice of the proposed IHA [79 FR 36743, June 30, VerDate Sep<11>2014 19:40 Sep 29, 2014 Jkt 232001 Corrected density from Redfern et al. (2013) 0.004 0.008 0.0065 0.006 2014]) were different from those used by ExxonMobil (in Table 3–1 of its IHA application). Although the reason for this discrepancy is not provided, it appears to the Commission that the abundance estimates in Table 5 of the Federal Register notice of the proposed IHA (79 FR 36743, June 30, 2014) were taken from the NMFS 2013 Pacific Stock Assessment Report (Carretta et al., PO 00000 Frm 00004 Fmt 4701 Sfmt 4703 Calculated takes/requested takes from Table 5 of the Federal Register notice of the proposed IHA 0.005/1 0.011/1 Corrected calculated takes/ authorized takes 0.00392/2 0.000362/2 2013). However, NMFS’s derived density estimates were incorrect for four of the species identified. Table 3 (below) lists the four marine mammal species in question, NMFS’s density estimates, and the Commission’s corrected densities, based on the abundance estimates provided by NMFS in Table 5 of the Federal Register notice of the proposed IHA (79 FR 36743, June 30, 2014). E:\FR\FM\30SEN3.SGM 30SEN3 Federal Register / Vol. 79, No. 189 / Tuesday, September 30, 2014 / Notices 58917 TABLE 3—PROPOSED AND CORRECTED DENSITY ESTIMATES, IN ANIMALS/KM2, FOR FOUR OF THE SPECIES/STOCKS PROPOSED TO BE TAKEN INCIDENTAL TO EXXONMOBIL’S CONDUCTOR PIPE INSTALLATION ACTIVITIES Density estimates from Table 5 of the Federal Register notice of the proposed IHA Species tkelley on DSK3SPTVN1PROD with NOTICES3 Gray whale ............................................................................................................................................... Cuvier’s beaked whale ............................................................................................................................ Mesoplodon spp. ..................................................................................................................................... Bottlenose dolphin ................................................................................................................................... Therefore, the Commission recommends that NMFS revise the density estimates for gray whales, Cuvier’s beaked whales, Mesoplodon spp., and common bottlenose dolphins to reflect the best available abundance estimates from Carretta et al. (2013); the corrected density estimates should then be used in NMFS’s revised take estimates. Response: The differences in the calculated densities reported in the IHA application (Tables 3–1 and 6–1 and the notice of the proposed IHA (79 FR 36743, June 30, 2014) were largely due to differences in abundance estimates and/or assumptions on seasonal variability (gray whale only), or due to combining abundance estimates of closely related stocks of selected species (e.g., killer whales). Where available, NMFS uses the abundance estimates for NMFS 2013 Pacific Stock Assessment Report (Caretta et al., 2013). Therefore, NMFS concurs with the Commission’s recommendation regarding gray whales, Cuvier’s beaked whales, Mesoplodon spp. beaked whales, and bottlenose dolphins, and has revised the abundance estimates and associated calculated and corrected density estimates. NMFS notes that these corrections produce little or no change in the number of calculated takes by Level B harassment for each of the identified species. An explanation of the density estimates and authorized take for each of the four species referenced in the Commission’s comments follows: • The gray whale density in the notice of the proposed IHA (79 FR 36743, June 30, 2014) is incorrect and should be approximately 1.5, based on the NMFS 2013 Stock Abundance Report. However, the corrected density estimate produces no change in the estimated take of 10 animals, which was increased (made more conservative based on group size and the schedule moving into the fall season, which is a VerDate Sep<11>2014 19:40 Sep 29, 2014 Jkt 232001 higher density time period to account for the southward migration. • The Cuvier’s beaked whale density estimate in the notice of the proposed IHA (79 FR 36743, June 30, 2014) is incorrect and should be approximately 0.523. The notice of the proposed IHA also gave an incorrect abundance estimate for this species (6,950). The abundance of Cuvier’s beaked whale abundance is 6,590 based on NMFS 2013 Stock Abundance Report (Caretta et al., 2013). Based on the corrected density estimate of 0.523 and a corrected abundance estimate of 6,590 animals, NMFS estimates that approximately 4 animals may be taken. • NMFS provided a density estimate of 0.08 for the Mesoplodon spp. beaked whale in the notice of the proposed IHA (79 FR 36743, June 30, 2014) based on an abundance of 1,024. Using the abundance estimate of 694 in the NMFS 2013 Stock Assessment Report, NMFS agrees with the Commission that the density estimate is 0.0551. This produces an estimated calculated take of approximately 1 animal using either abundance estimate. However, NMFS is authorizing take of 2 animals based on group size. • The bottlenose dolphin density estimate in the notice of the proposed IHA (79 FR 36743, June 30, 2014) is incorrect and should be approximately 0.08, based on the offshore abundance of the stock. Common bottlenose dolphin densities in the IHA application and notice of the proposed IHA (79 FR 36743, June 30, 2014) were 0.11 based on an abundance of 1,329, derived from combining the coastal and offshore stocks (323 + 1,006). However, California coastal bottlenose dolphins are found within one km (0.54 nmi) of shore primarily from Point Conception south into Mexican waters, at least as far south as San Quintin, Mexico; therefore, we do not expect the coastal stock to be taken by the conductor pipe installation activities and do not consider this stock PO 00000 Frm 00005 Fmt 4701 Sfmt 4703 0.5067 0.17 0.08 0.11 Corrected density estimates, derived from abundance estimates in Table 5 of the Federal Register notice of the proposed IHA 1.519 0.523 0.055 0.080 further in this analysis (Hansen, 1990; Caretta et al., 1998; Defran and Weller, 1999). In southern California, animals are found within 500 m (0.27 nmi) of shoreline 99% of the time and within 250 m (0.13 nmi) 90% of the time (Hanson and Defran, 1993). The original calculated take estimates for bottlenose dolphins was 0.15, based on a density of 0.11. The corrected calculated take estimate is 0.4829, based on the corrected density of 0.0799. However, the corrected density estimate produces no change in the estimated take of 10 animals, which was increased (made more conservative) based on group size. Comment 3: The Commission states that ExxonMobil estimated the numbers of marine mammal takes by multiplying the species specific densities by the area of the Level B harassment buffer zone (0.3188 km2) and the duration of the proposed conductor pipe installation activities. ExxonMobil calculated the latter as a total of 4.125 days for all six conductor pipes, apparently by summing each period of proposed conductor pipe installation activities and then dividing that cumulative exposure time by 24 hours to determine the number of days of exposure. Because pipe-driving sessions are interspersed between periods of no pipe-driving, summing across only pipedriving periods underestimates the number of days of actual exposure. Instead, ExxonMobil should have summed across the entire pipe-driving timeframe, which includes period of no pipe-driving to determine the number of days animals would be exposed, because each day of pipe-driving has the potential to expose either the same animals repeatedly or different animals. The Commission states that the take estimates should account for multiple days of exposure rather than aggregated hours of exposure. In this instance, ExxonMobil should have added 3.3 hours of estimated pile-driving per section to 7.3 hours of downtime per E:\FR\FM\30SEN3.SGM 30SEN3 tkelley on DSK3SPTVN1PROD with NOTICES3 58918 Federal Register / Vol. 79, No. 189 / Tuesday, September 30, 2014 / Notices section for a total of 10.6 hours per section of pipe. Multiplying that by the projected seven sections to be driven for each conductor pipe would result in a total of 74.2 hours, which when divided by 24 hours per day equated to 3.1 days of potential exposure per pipe. Using that method would yield a total of 18.6 days of potential exposure (3.1 days per conductor pipe multiplied by 6 pipes), which more accurately represents the total duration of proposed conductor pipe installation activities for all six conductor pipes. Accordingly, the Commission recommends that NMFS revise its take estimates for all species/ stocks to account for the total number of days of potential exposure (i.e., 18.6 days), ensuring a more accurate estimate of potential takes. The CBD also states that NMFS underestimates the impacts as the planned conductor pipe installation activities are intermittent and not continuous as described in the notice of the proposed IHA (79 FR 36743, June 30, 2014). Authorizing take based on this assumption underestimates actual take, which would occur over a much greater amount of time as it could impact communication and navigation of marine mammals in the action area. Response: NMFS concurs with the Commission’s recommendations and has revised the take calculations to account for 18.6 days of potential exposure. See Table 7 for the updated re-calculated take estimates and authorized take numbers. Comment 4: The Commission states that ExxonMobil adjusted its take estimates by a factor of at least 10 for a number of species to account for group size. NMFS based its proposed take estimates on ExxonMobil’s requested takes for all species except two—sperm whales and short-beaked common dolphins. NMFS proposed takes for a single sperm whale and 45 common dolphins, derived directly from density estimates with no adjustment for group size. Those two species typically occur in groups that may exceed the requested numbers of takes. Sperm whales typically occur in groups of 2 to 10 whales (Barlow et al., 2005), and common dolphins occur in groups of hundreds to thousands of animals (Reeves et al., 2002). If those species were to be observed in the vicinity of the project area, they likely would occur in numbers that exceed the requested number of takes. That could result in actual takes exceeding the authorized numbers of takes and/or premature shut-down of the proposed activities. In other similar situations, NMFS has increased the requested number of takes of a particular species to reflect the VerDate Sep<11>2014 19:40 Sep 29, 2014 Jkt 232001 mean group size of that species (e.g., Table 4 in 78 FR 33811). Therefore, to ensure that the requested numbers of takes reflect numbers of individuals of each species that may be observed in the project area, the Commission recommends that NMFS increase its estimated numbers of takes for sperm whales and short-beaked common dolphins to reflect the minimum typical group size for each species (i.e., at least 2 and 450 animals, respectively). Response: NMFS concurs with the Commission’s recommendation and has increased the takes of sperm whales and short-beaked common dolphins from 1 and 45 to 2 and 450, respectively. NMFS has also increased the authorized take numbers for humpback (from 1 to 2), minke (from 1 to 2), sei (from 1 to 2), fin (from 1 to 2), blue (from 1 to 2), Baird’s beaked (from 1 to 6), Cuvier’s beaked (from 1 to 4), Mesoplodon spp. (from 1 to 2), killer (from 1 to 10), and short-finned pilot whales (from 1 to 40) as well as northern right whale dolphins (from 1 to 100) to account for average group size (Jefferson et al., 2008). Comment 5: The CBD states that NMFS underestimates the harmful impact of the proposed conductor pipe installation activities on endangered blue whales. The Santa Barbara Channel is important blue whale habitat. The global blue whale population has been reduced by commercial whaling from over 300,000 to likely fewer than 10,000 individuals. Blue whales off California are part of a population comprised of about 1,647 animals; scientists estimate that even three human-caused deaths each year will impede the recovery of the California population. Nine blue whales have died from collisions with ships from 2007 to 2011; this means that human-caused mortality of blue whales already exceeds the sustainable amount. Response: NMFS fully considered the potential impacts of the planned conductor pipe installation activities on endangered blue whales. As described in the notice of the proposed IHA (79 FR 36743, June 30, 2014), NMFS anticipates only low level disturbance of blue whales, if any, in the form of Level B harassment. NMFS is authorizing take of two blue whale by Level B harassment only; no injury, serious injury, or mortality is anticipated or authorized. The potential impacts of the conductor pipe installation activities are expected to be temporary and are is not expected to have adverse consequences on the affected stock, including reductions in reproduction, numbers, or distribution that might appreciably reduce the stock’s likelihood of surviving and recovering in the wild. PO 00000 Frm 00006 Fmt 4701 Sfmt 4703 NMFS’s Office of Protected Resources, Permits and Conservation Division, also initiated and engaged in formal consultation under section 7 of the ESA with NMFS’s West Coast Regional Office, Protected Resources Division, on the issuance of an IHA under section 101(a)(5)(D) of the MMPA for this activity. NMFS’s West Coast Regional Office, Protected Resources Division issued a Biological Opinion addressing the effects of the proposed action on threatened and endangered species, including the blue whale. The Biological Opinion concluded that the proposed action is not likely to jeopardize the continued existence of the blue whale. Comment 6: The CBD states that blue whales congregate throughout the Santa Barbara Channel (it hosts the world’s densest summer seasonal congregation), and Harmony Platform is in the region that is an important area for blue whales. A recent tagging study determined the areas of highest use by blue whales off the West Coast. Researchers tagged 171 blue whales between 1993 and 2008, and the area of highest use was the western area in the Santa Barbara Channel (see Figure 1 of CBD’s comments). The study showed that blue whales use the entire area of waters in southern California, but that the Santa Barbara Channel is the most heavily used. Between June and November, high densities of blue whales spend time feeding on the abundant planktonic krill in the area of this project (see Figure 2 of CBD’s comments). The blue whales use the project area for foraging, and the conductor pipe installation activities will interfere with this important life function. Blue whales will be exposed to sounds that could have auditory damage, but could also be displaced from important foraging grounds. Response: Harmony Platform, which is located at 34 22′35.906″ North and 120 10′04.48 West, is on the coastal side of the shipping lane in the Santa Barbara Channel (see Figure 1–1 of the IHA application). Based on Figure 1 from CBD’s letter (adapted from Irvine [2014]), this location is in the lowest density area of blue whales in the U.S. Exclusive Economic Zone near the Channel Islands based on satellite tracks, with only 1 to 5 blue whales observed from 1998 to 2008. The highest density area (20 to 26 blue whales) shown in Figure 1 of CBD’s letter is located further offshore from the shipping channel, and roughly coincides with the area of highest krill density in the California Current reported by Santora et al. (2011), which is approximately 30 to 50 km (16.2 to 27 E:\FR\FM\30SEN3.SGM 30SEN3 tkelley on DSK3SPTVN1PROD with NOTICES3 Federal Register / Vol. 79, No. 189 / Tuesday, September 30, 2014 / Notices nmi) from Harmony Platform. These distribution correlations are expected given that krill comprise the majority of the blue whale’s diet, and indicate that blue whales rarely forage or congregate within 5 to 10 km (2.7 to 5.4 nmi) of Harmony Platform, which is well outside of the expected 325 m buffer zone for Level B harassment. NMFS anticipates only low level disturbance of blue whales, if any, in the form of Level B harassment, as Harmony Platform is located in an area of lowest blue whale density and second lowest krill density in the California Current (see Santora et al., 2011, Figure 5). NMFS does not expect the conductor pipe installation activities to displace blue whales from foraging grounds. Comment 7: CBD states that new science shows that blue whales, and possible other baleen whales, are highly susceptible to behavioral disturbance from noise pollution. The Goldbogen et al. (2013) study raises substantial concern because it demonstrates the potential impacts of high intensity noise on the essential life functions of blue whales. The study found that midfrequency sonar can disrupt feeding and displace blue whales from high-quality prey patches, significantly impacting their foraging ecology, individual fitness, and population health. Even fairly low-received levels can have an adverse impact. Response: The Goldbogen et al. (2013) study analyzed behavioral responses of tagged blue whales in response to simulated military sonar and other midfrequency sounds used during a controlled exposure experiment in feeding areas within the Southern California Bight. The study concluded that the responses of animals to midfrequency sonar were complex, dependent on the behavioral state and sound exposure factors, and represented a general avoidance response of a perceived threat that appeared to subside quickly after sound exposure. ExxonMobil’s conductor pipe installation activities would not generate the same sound characteristics as the military sonar and other midfrequency sounds that were used during those controlled exposure experiments. Moreover, the IHA requires ExxonMobil to implement monitoring and mitigation measures to avoid exposing marine mammals, including blue whales, to sounds levels that could have potential adverse impacts. As described in the notice of the proposed IHA (79 FR 36743, June 30, 2014), NMFS anticipates only low level disturbance of marine mammals in the form of Level B harassment from ExxonMobil’s activities. NMFS does not anticipate VerDate Sep<11>2014 19:40 Sep 29, 2014 Jkt 232001 significant impacts to the foraging behavior, individual fitness, or population health of blue whales in the action area. Comment 8: The CBD states that the best available science indicates western North Pacific gray whales may be present in the survey area. Recently, a tagged western North Pacific gray whale traveled all the way from Sakhalin Island, Russia, to the west coast of North America, indicating that the population may merge with the eastern North Pacific population during migration and may therefore be taken by activity. There are currently an estimated 155 western North Pacific gray whales left in the world. With such low population numbers, the take of even one of these whales would have greater than negligible impacts on the species or stock. Response: Western North Pacific gray whales are not expected to occur in the action area. There is evidence of movement between ‘‘eastern’’ and ‘‘western’’ populations of North Pacific gray whales, but the evidence thus far only supports low inter-area movements. For gray whales that migrate along the continental U.S., evidence from photo-identification work supports only seven confirmed western gray whale sightings (as well as a single satellite-tracked individual) ever in the central and eastern Pacific Ocean compared to roughly 20,000 individuals composing the eastern North Pacific population, which has been tracked for decades (Mate et al., 2011; Burdin et al., 2011; Weller et al., 2011). These sightings occurred along Alaska, Washington, and Oregon, where foraging could occur. Urban et al. (2012) matched 13 individuals through photoidentification between summer feeding grounds in Russia and winter breeding lagoons in Mexico. The only motivation for an individual to continue further south (beyond foraging opportunities) is to participate in breeding and calving in lagoons of Baja California (Mexico) and the Gulf of California. However, numerous studies have found that genetic exchange between eastern and western populations is not occurring to a significant level (Leduc et al., 2002; Lang et al., 2004; Weller et al., 2004b; Lang et al., 2005; Swartz et al., 2006; Weller et al., 2006a; Weller et al., 2007; Brownell Jr. et al., 2009; Kanda et al., 2010; Lang et al., 2010b; Burdin et al., 2011). Moore and Weller (2012) determined the probability of taking a single gray whale from the western population during the proposed Makah Indian Tribe hunt as 0.014 to 0.051 during a single year. NMFS does not expect western North Pacific gray PO 00000 Frm 00007 Fmt 4701 Sfmt 4703 58919 whales to occur in the action area due to the lack of documented trans-Pacific movement (particularly as far as the action area) as well as the lack of rationale for gray whales from the western population to move through the area. Comment 9: The CBD states that the North Pacific right whale is a potentially impacted species for which no take may be authorized. There are an estimated 25 to 30 individuals in the eastern stock of North Pacific right whales, making it the most highly endangered large whale in the world (Wade et al., 2011). Although NMFS notes that North Pacific right whales may be present in the project area, it assumes, without support, that no North Pacific right whales will be taken. Response: The North Pacific right whale is rarely found off the U.S. west coast. The majority of North Pacific right whale sightings from the eastern North Pacific stock occur in the Bering Sea and adjacent areas of the Aleutian Islands and Gulf of Alaska. Sightings of this species have been reported as far south as central Baja California in the eastern North Pacific, as far south as Hawaii in the central North Pacific, and as far north as the sub-Arctic waters of the Bering Sea and Sea of Okhotsk in the summer. Data from passive acoustic monitoring indicates that North Pacific right whales are present year-round in the southeastern Bering Sea, with peaks in the late summer (August to September). Although individuals may travel south from the high-latitudes of the Bering Sea to lower-latitudes, animals that have been sighted in waters off Hawaii or tropical Mexico have been considered extralimital for this species (Brownell et al., 2001). The North Pacific right whale has not been observed near Harmony Platform. Therefore, no takes of North Pacific right whales are anticipated or authorized by NMFS. Although North Pacific right whales are not expected to occur in the action area, NMFS’s Office of Protected Resources, Permits and Conservation Division also considered the conservation status, rarity, and habitat of ESA-listed marine mammals (including the North Pacific right whale) when developing mitigation measures for the conductor pipe installation activities. Included in the IHA are special procedures for situations or species of concern (see ‘‘Mitigation’’ section below). If a North Pacific right whale is visually sighted during the conductor pipe installation activities, the pipe-driving activities must be shutdown regardless of the distance of the animal(s) to the sound source. The pipedriving will not resume firing until 30 E:\FR\FM\30SEN3.SGM 30SEN3 tkelley on DSK3SPTVN1PROD with NOTICES3 58920 Federal Register / Vol. 79, No. 189 / Tuesday, September 30, 2014 / Notices minutes after the last documented whale visual sighting. Comment 10: The CBD states that sperm whales reach peak abundance in California from April through mid-June and from the end of August through mid-November, which is during the time of the proposed conductor pipe installation activities. Any take of a sperm whale would have greater than negligible impacts on the stock because NMFS must take into account the cumulative take of sperm whales from other activities, including incidental catch by fisheries. The California drift gillnet fishery, which operates primarily in southern California from August through January, took an estimated sixteen endangered sperm whales in the 2010 to 2011 fishing season (Caretta and Enriquez, 2012). Including both fishery and ship-strike mortality, the average annual rate of kill and serious injury is four sperm whales, exceeding the potential biological removal level of 1.5 (Caretta et al., 2012). With an estimated 971 sperm whales in the population, this level of anthropogenic take cannot be considered a negligible impact. Response: Sperm whale abundance varied off California between 1979/1980 and 1991 (Barlow, 1994) and between 1991 and 2008 (Barlow and Forney, 2007). The most recent estimate from 2008 is the lowest to date, in sharp contrast to the highest abundance estimates obtained from NMFS’s 2001 and 2005 surveys. However, there is no reason to believe that the population has declined; the most recent survey estimate likely reflects inter-annual variability in the study area. To date, there has not been a statistical analysis to detect trends in abundance. NMFS’s 2013 Stock Assessment Report estimated a sperm whale abundance of 971 individuals for the California/ Oregon/Washington stock. A new analysis by Moore and Barlow (in press) estimates a population abundance of approximately 21,31 animals (1,332 minimum). NMFS expects potential impacts by Level B harassment only to sperm whales; no injury, serious injury, or mortality is anticipated or authorized. The potential impacts are expected to be temporary and the action is not expected to have adverse consequences on the stock, including reductions in reproduction, numbers, or distribution that might appreciably reduce the stock’s likelihood of surviving and recovering in the wild. Based on our analysis of the likely effects of the action on sperm whales and their habitat, and taking into consideration the implementation of the required monitoring and mitigation measures VerDate Sep<11>2014 19:40 Sep 29, 2014 Jkt 232001 (see ‘‘Mitigation’’ below), NMFS finds that the take of small numbers of sperm whales by Level B harassment incidental to ExxonMobil’s conductor pipe installation activities will have a negligible impact on the affected marine mammal species or stocks. NMFS’s Office of Protected Resources, Permits and Conservation Division, also initiated and engaged in formal consultation under section 7 of the ESA with NMFS’s West Coast Regional Office, Protected Resources Division, on the issuance of an IHA under section 101(a)(5)(D) of the MMPA for this activity. NMFS’s West Coast Regional Office, Protected Resources Division issued a Biological Opinion addressing the effects of the proposed action on threatened and endangered species, including the sperm whale. The Biological Opinion concluded that the proposed action is not likely to jeopardize the continued existence of the sperm whale. Comment 11: The CCC states that sea surface temperatures off of southern California and in the eastern north Pacific Ocean at large have been above normal for several months, and with an apparent El Nino event emerging in the equatorial Pacific Ocean later this year, are likely to remain elevated through the fall, winter, and into 2015. As a consequence of the unusually warm waters, marine mammal species more typical of subtropical latitudes have been sighted off of southern California and in the Santa Barbara Channel. These species may continue to be present in numbers and locations beyond those that can be reflected accurately by density estimates derived from long term survey and abundance datasets. These include cetaceans such as Bryde’s whales (Balaenoptera brydei), false killer whales (Pseudorca crassidens), and short-finned pilot whales (Globicephala macrorhynchus), which have rarely been seen off the California coast in recent years. In light of these unusual environmental conditions, it may be necessary for NMFS to consider whether additional species could be exposed to the conductor pipe installation activities, and to revisit the species abundance assumptions underlying its incidental take calculations for the species already evaluated in the proposed IHA. Response: NMFS has received anecdotal reports from the public, whale watching companies, and other sources of recent sightings of Bryde’s, false killer, and short-finned pilot whales. As discussed in the notice of the proposed IHA (79 FR 36743, June 30, 2014), these three species are generally found south of the Santa Barbara Channel and are PO 00000 Frm 00008 Fmt 4701 Sfmt 4703 unlikely to be found in the action area. Bryde’s whales are extremely rare in the Southern California Bight, with fewer than ten confirmed sightings from August 2006 to September 2010 (Smultea et al., 2012). NMFS West Coast Regional Office has received reports of up to 4 individual Bryde’s whales sighted in the summer of 2014 and has had a total of 12 sightings ever documented in the past. NMFS West Coast Regional Office has received reports of up to 40 short-finned pilot whales sighted off the Channel Islands and elsewhere. A group of approximately 50 short-finned pilot whales were sighted off the coast of Dana Point in Orange County in June 2014. A group of approximately 40 to 70 false killer whales were sighted off the coast of Dana Point in March 2014. NMFS concurs with the CCC’s recommendation and has authorized take, by Level B harassment, for Bryde’s, false killer, and short-finned pilot whales based on the possibility of encountering a single individual Bryde’s whale or a group of false killer and/or short-finned pilot whales in the action area of the planned conductor pipe installation activities at Harmony Platform. NMFS has also revisited the species abundance assumptions for all of the marine mammal species and has adjusted density estimates for those that occur in the California Current ecosystem. See Table 7 for the revised density estimates and authorized take numbers for these marine mammal species. Comment 12: The CBD is concerned with NMFS’s conclusion to exclude consideration of Guadalupe fur seals, which are rarely sighted animals with ranges within the action area. Response: NMFS does not expect Guadalupe fur seals to be in the immediate action area or exposed to sounds generated by the conductor pipe installation activities. Guadalupe fur seals occur primarily near Guadalupe Island, Mexico, their primary breeding area. They are found north of the U.S.Mexican border with a very small number of adults and pups observed on San Miguel Island (the western-most Channel Island in the Southern California Bight). Guadalupe fur seal strandings have occurred in California and north into Washington, which indicates that they must transit through southern California from Mexico to these areas where they have stranded. However, the encounter rate in the action area is considered to be very low. While they could potentially transit through the general area, NMFS considers it unlikely that they would be exposed to levels of sound associated E:\FR\FM\30SEN3.SGM 30SEN3 Federal Register / Vol. 79, No. 189 / Tuesday, September 30, 2014 / Notices tkelley on DSK3SPTVN1PROD with NOTICES3 with take, given their rare occurrence in the area, the duration of the activities, and the size of the ensonified area. Mitigation Comment 13: The CBD states that the mitigation measures are inadequate to ensure the least practicable adverse impact. If NMFS decides to approve the action it must require additional monitoring and mitigation measures to implement the least practicable impact on marine mammals. Response: NMFS’s Office of Protected Resources, Permits and Conservation Division considered a number of mitigation measures before issuing the IHA, including measures proposed by ExxonMobil and additional measures recommended by the public. NMFS’s Office of Protected Resources, Permits and Conservation Division has determined that the monitoring and mitigation measures required by the IHA provide the means of effecting the least practicable impact on species or stocks and their habitat, paying particular attention to rookeries, mating grounds, and areas of similar significance. Comment 14: The CBD states that NMFS must fully analyze time-area restrictions as a mitigation measure. NMFS must not allow pipe-driving when blue whales aggregate in the Santa Barbara Channel during June through November. The western portion of the Santa Barbara Channel, where Harmony Platform is located, provides a core area for the blue whales, and pipe-driving should be restricted in this important habitat for blue whales. This closure should further be extended to avoid overlap with the presence of other whales. Response: NMFS disagrees with the CBD that time-area restrictions are necessary as a mitigation measure. The Harmony Platform is located at 34 22’ 35.906’’ North and 120 10’ 04.48’’ West, on the coastal side of the shipping lane in the Santa Barbara Channel (see Figure 1 of the IHA application). Based on Figure 1 in CBD’s comment letter (adapted from Irvine, 2014), this location is in the lowest density of blue whales in the U.S. Exclusive Economic Zone near the Channel Islands based on satellite tracks, with only 1 to 5 blue whales observed from 1998 to 2008 (yellow zone in Figure 1). The highest density area shown in Figure 1 (20 to 26 blue whales) is located further offshore from the shipping lane, and roughly coincides with the area of highest krill density in the California Current reported by Santora et al. (2011), which is approximately 30 to 50 km from Harmony Platform. These distribution VerDate Sep<11>2014 19:40 Sep 29, 2014 Jkt 232001 correlations are expected given that krill comprise the majority of the blue whale’s diet, and indicate that blue whales rarely forage or congregate within 5 to 10 km of Harmony Platform. Therefore, given that the areas of highest blue whale density and krill density near the Channel Islands are well outside the 325 m buffer zone for the pipe-driving activities, NMFS disagrees that time-area restrictions for the blue whale are necessary. Comment 16: The CBD states that NMFS must fully analyze larger exclusion zones as a mitigation measure. The use of more accurate thresholds would lead to larger exclusion zones. Additionally, the modeled distances disagree with measured sound levels for other piledriving activities. The exclusion zone of 3.5 m for pinnipeds and 10 m for cetaceans is woefully inadequate to mitigate Level A harassment. Bailey et al. (2010) measured 205 dB of broadband sound at 10 m from the piledriving source. While the source was louder at 226 dB in that study, it indicates that the exclusion zone should be much larger. Response: NMFS disagrees with the CBD’s comment. For a response to CBD’s comment regarding NMFS’ thresholds for Level A harassment, see the response to comment 21 (below) X. NMFS and ExxonMobil are not aware of any available in-situ measurements of underwater sound using a 90 kJ impact hammer with a 66 cm (26 in) diameter steel, 426.7 to 457.2 m (1,400 to 1,500 ft) pipe, in which case, acoustic modeling is an appropriate and oft-used scientifically defensible method available to estimate the buffer and exclusion zones established for potential impact and mitigation purposes. A detailed acoustic modeling report by JASCO titled ‘‘Assessment of Airborne and Underwater Noise from Pile Driving Activities at the Harmony Platform’’ was provided to NMFS with the IHA application, and includes detailed information on the computer model, uncertainties, and associated input parameters used to calculate distance to the buffer (Level B harassment) and exclusion (Level A harassment) zones. NMFS evaluated the report and determined that it provided sufficient support to establish predicted buffer and exclusion zones. Moreover, these predicted underwater and in-air sound levels will be assessed for accuracy when the monitoring data is analyzed after installation of the first conductor pipe, and the buffer and exclusion zones will be revised as necessary for the installation of the PO 00000 Frm 00009 Fmt 4701 Sfmt 4703 58921 remaining pipes based on the results of the sound source verification. Bailey et al. (2010) assessed the potential effects of underwater noise levels during pile-driving at an offshore windfarm on marine mammals; however, the piles and pile-driving technical details as well as the sound analysis in that study are different than those planned to be used during ExxonMobil’s conductor pipe installation activities. The Bailey et al. (2010) study was conducted for the installation of wind turbines using much shorter ‘‘piles’’ in water depths of approximately 40 m (131.2 ft) (hammer specifications unknown); therefore, the underwater and in-air noise estimates and corresponding buffer and exclusion zones are not comparable between the two projects. This is because underwater sound propagation is a function of sound source energy and frequency, water depth and physical structure (e.g., salinity, temperature), bottom sediment type (hardness, porosity), and pipe material (e.g., steel, concrete) and size; all of which differ between the Bailey et al. (2010) site and the Harmony Platform site. Comment 16: The CBD states that NMFS must fully analyze air bubble curtains, which can reduce sound by 20 to 30 dB depending on their design, or explore the use of other noise reduction technologies (e.g., pile caps, dewatered cofferdams, and other physical barriers) for mitigating underwater sound from impact hammer pipe-driving. Response: NMFS and ExxonMobil evaluated the potential use of air bubble curtains to reduce the underwater sound generated during pipe-driving activities in a water depth of 365.8 m (1,200 ft). The use of an air bubble curtain is not feasible due to interference of the jacket infrastructure at Harmony Platform, and the water depth and current speed (greater than 10 meters per second) at the activity site, which prevents the ability to maintain a constant air bubble density along the conductor length that would be effective at reducing underwater sound from the conductor pipe installation activities. The conductor pipes are being installed in 365.8 m of water through 76.2 cm (30 in) guides that are attached to structural members on the Harmony Platform; therefore, an air bubble curtain would be ineffective at reducing the output sound level, as bubbles would be dispersed and carried by currents away from the pipe and redirected by interference from the surrounding jacket members and conductor infrastructure. Because the conductors pass through 365.8 m of water column, another issue that eliminated this sound reduction E:\FR\FM\30SEN3.SGM 30SEN3 tkelley on DSK3SPTVN1PROD with NOTICES3 58922 Federal Register / Vol. 79, No. 189 / Tuesday, September 30, 2014 / Notices technique from consideration was that the air nozzles used to generate the air bubbles would most likely freeze-up before reaching the sea bottom due to the pressure and cold temperatures of the water, which would render the air bubble curtain ineffective. All known applications of air bubble curtains that have effectively reduced sound by 20 to 30 dB have been used at depths shallower than 365.8 m and in waters with current velocities that are less than those commonly encountered in Santa Barbara Channel. NMFS and ExxonMobil also evaluated the potential use of a dewatered cofferdam to reduce the underwater sound generated during conductor pipe installation activities. The installation of a dewatered cofferdam around each conductor installation is not feasible due to the 365.8 ft water depth and corresponding pressure. In addition, each conductor has a limited footprint and has subsea interference from the jacket infrastructure. Also, a cofferdam would have to be driven into the sea bottom at a depth of 365.8 m to provide structural stability and protection from water currents, which would create additional potential impacts to marine mammals in the action area. NMFS and ExxonMobil also explored a physical noise abatement technology using flexible air-filled resonators that are lowered in multiple long hoses along the sides of each conductor prior to conductor pipe installation activities. The resonators would be filled with air in a hose-like structure that would close the gap around the conductors. This technology is not fully developed, and the scale of this noise abatement system would be unprecedented and impossible to install around Harmony Platform. The deepest known noise abatement system was installed in approximately 36.6 m (120 ft) of water, which is just one tenth of the depth where the planned conductor pipe installation activities will occur. This technology also has the same limitations as a bubble curtain, in that it uses air as the delivery system to fill the resonator and attenuate sound. At a water depth of 365.8 m, air would likely form hydrates prior to filling the resonators, which would render this approach ineffective. Comment 17: The CBD states that NMFS must fully analyze and should restrict conductor pipe installation activities so that they do not occur during low visibility. The action is a 24hour, continuous activity with pipedriving potentially happening at night and during low visibility. The PSOs are ineffective at night and during low visibility. This means that during those VerDate Sep<11>2014 19:40 Sep 29, 2014 Jkt 232001 times the exclusion zone will not be effective in mitigating take by Level A harassment. Furthermore, artificial lighting, while better for PSOs, brings hazards to migratory birds. Response: NMFS disagrees with the CBD’s comment. The IHA does consider and address conductor pipe installation activities during low-visibility and nighttime conditions. If inclement weather conditions (i.e., fog, rain, or rough Beaufort sea state) limit or impair PSO’s visibility of the water’s surface to less than 30.5 m (100 ft) within the action area, all noise-generating conductor pipe installation activities must be stopped until visibility improves. To facilitate visual monitoring during non-daylight hours, the exclusion zones must be illuminated by lights to allow for more effective viewing of the area by the PSO on-duty. ExxonMobil is providing artificial lighting for conductor pipe installation activities during nighttime and low visibility operations at the +15 ft level of the Harmony Platform that will provide adequate visibility to allow observation of the 3.5 m and 10 m exclusion zones for pinnipeds and cetaceans, respectively, as well as the surrounding areas. The lighting will only be on for those periods when conductor pipes are being driven at night or during periods of low visibility which typically occur for only a short period of time during the activities using the impact hammer. The artificial lighting that will be installed will have light shields attached to direct the light downward toward the water. Note that the Harmony Platform has existing lighting to allow for safe operations and to comply with regulations. ExxonMobil will continue its current monitoring practices throughout the planned conductor pipe installation activities, and will note any increase in bird activity during nighttime operations. Monitoring and Reporting Comment 18: The Commission states that the accurate characterization of the sizes of the buffer and exclusion zones is critical for implementing mitigation measures and estimating the numbers of animals taken. In the past, the Commission has recommended a rapid turnaround of the in-situ sound source verification analysis to ensure that buffer and exclusion zones are the appropriate size. However, in at least one instance, rapid turnaround has resulted in errors, as occurred with ION’s measurements of source levels during its 2012 Arctic in-ice survey. In that case, the size of the exclusion zone was decreased from that modeled based on erroneous field-report results. The PO 00000 Frm 00010 Fmt 4701 Sfmt 4703 error was not discovered until the end of the field season, when it was determined that the in-season adjustments resulted in unauthorized Level A harassment takes of bowhead whales. Since the purpose of sound source verification is to ensure protection of marine mammals, one way to reduce risk to marine mammals would be to allow only for expansion, but not contraction, of the buffer and/or exclusion zones after in-situ adjustment in the size of the buffer and/or exclusion zones if the size(s) of the estimated zones are determined to be too small. The CCC also supports an adaptive approach to adjusting the buffer and exclusion zones based on in-situ data collected during the sound source verification. The process of adjusting the zones should begin from a protective baseline. Response: Monitoring will be performed during all impact hammer pipe-driving operations. Hydrophones will be deployed prior to the start of impact hammer pipe-driving the first pipe section. Data will be collected and analyzed upon completion of the conductor pipe’s last pipe section. Monitoring equipment will be redeployed prior to installation of the remaining five conductor pipes. Upon completion of the first conductor pipe, acoustic data will be retrieved from the near field (approximately 10 m) and far field (approximately 325 to 500 m) recorders, analyzed, and compared to the predicted rms radii distances for the buffer and exclusion zones. ExxonMobil will consult with NMFS prior to proceeding with conductor pipe installation activities in the event that acoustic field data indicate that predicted radii distances for the buffer and exclusion zones need to adjusted (either expanded or contracted). Distances will be recalculated using field data, and monitoring equipment will be redeployed at the corrected distances prior to installation of the remaining conductor pipes, following authorization from NMFS. The planned extended down period (non-hammering) between the completion of the first pipe installation and the start of the second pipe installation will be used to determine the actual size of buffer and exclusion zones (i.e., Level B and Level A harassment zones) to ensure that the radii estimated from acoustic modeling are not too small. Comment 19: The CCC states that due to the uncertainties with modeling, site specific, and/or seasonal oceanographic conditions, they request being provided copies of the monitoring reports referenced in the notice of the proposed IHA (79 FR 36743, June 30, 2014) for E:\FR\FM\30SEN3.SGM 30SEN3 Federal Register / Vol. 79, No. 189 / Tuesday, September 30, 2014 / Notices tkelley on DSK3SPTVN1PROD with NOTICES3 ExxonMobil’s conductor pipe installation activities. If monitoring indicates impacts greater than anticipated, CCC intends to continue to work with NMFS to assure the activity can be modified accordingly to minimize effects on marine mammals. Response: NMFS will provide copies of the in-water and in-air monitoring and sound source verification report for ExxonMobil’s conductor pipe installation activities to the CCC when the document has been completed (after the first conductor pipe has been installed and, the in-situ measurements taken). NMFS will also provide the final 90-day monitoring report required by the IHA to the CCC and make it publicly available on our Web site at: https:// www.nmfs.noaa.gov/pr/permits/ incidental.htm#iha. Acoustic Thresholds Comment 20: CBD states that NMFS’s current 160 dB threshold for Level B harassment in the notice of the proposed IHA (79 FR 36743, June 30, 2014) does not reflect the best available science and is not sufficiently conservative. CBD state that in particular, the 160 dB threshold is nonconservative, because the scientific literature establishes that behavioral disruption can occur at substantially lower received levels for some species. Response: NMFS’s practice has been to apply the 160 dB received level threshold for underwater impulse sound levels to determine whether take by Level B harassment occurs. Specifically, NMFS derived the 160 dB threshold data from mother-calf pairs of migrating gray whales (Malme et al., 1983, 1984) and bowhead whales (Richardson et al., 1985, 1986) responding to airgun operations. NMFS acknowledge there is more recent information bearing on behavioral reactions to sound sources such as pile-driving, seismic airguns, sonars, electromechanical devices, etc., but those data only illustrate how complex and context-dependent the relationship is between the various sound sources, and do not, as a whole, invalidate the current threshold. Accordingly, it is not a matter of merely replacing the existing threshold with a new one. NMFS discussed the science on this issue qualitatively in our analysis of potential effects to marine mammals in the Federal Register notice of the proposed IHA (79 FR 36743, June 30, 2014). NMFS is currently developing revised acoustic guidelines for assessing the effects of anthropogenic sound on marine mammals. Until NMFS finalizes these guidelines (a process that includes internal agency review, public notice and comment, and peer review), NMFS VerDate Sep<11>2014 19:40 Sep 29, 2014 Jkt 232001 will continue to rely on the existing criteria for Level A and Level B harassment shown in Table 4 of the notice of the proposed IHA (79 FR 36743, June 30, 2014). As mentioned in the Federal Register notice of the proposed IHA (79 FR 36743, June 30, 2014), NMFS expects that the onset for behavioral harassment is largely context dependent (e.g., behavioral state of the animals, distance from the sound source, etc.) when evaluating behavioral responses of marine mammals to acoustic sources. Although using a uniform sound pressure level of 160 dB for the onset of behavioral harassment for impulse noises may not capture all of the nuances of different marine mammal reactions to sound, it is an appropriate way to manage and regulate anthropogenic noise impacts on marine mammals until NMFS finalizes its acoustic guidelines. Comment 21: CBD states that NMFS’s use of the 180 and 190 dB thresholds for estimating Level A harassment and the likelihood of temporary and/or permanent threshold shift do not consider the best available science and is not sufficiently conservative. CBD cites Kastak et al. (2008), Lucke et al. (2009), Wood et al. (2012) and Kajawa and Liberman (2009). Response: As explained in the notice of the proposed IHA (79 FR 36743, June 30, 2014), ExxonMobil will be required to establish a 180 and 190 dB re 1 mPa exclusion zone for marine mammals before the conductor pipe installation activities begin. NMFS expects that the required platform-based visual monitoring of the exclusion zones is appropriate to implement mitigation measures to prevent Level A harassment. If the PSOs observe marine mammals approaching the exclusion zone, ExxonMobil must shut-down pipe driving to ensure that the marine mammal does not approach the applicable exclusion radius. The avoidance behaviors discussed in the notice of the proposed IHA (79 FR 36743, June 30, 2014) also supports our expectations that individuals will avoid exposure at higher levels. NMFS’s current Level A thresholds, which identify levels above which PTS could be incurred, were designed to be precautionary in that they were based on levels were animals had incurred TTS. NMFS is currently working on finalizing acoustic guidance that will identify revised TTS and PTS thresholds that references the studies identified by CBD. In order to ensure the best possible product, the process for developing the revised thresholds includes both peer and public review PO 00000 Frm 00011 Fmt 4701 Sfmt 4703 58923 (both of which have already occurred) and NMFS will begin applying the new thresholds once the peer and public input have been addressed and the acoustic guidance is finalized. Regarding the Lucke et al. (2009) study, the authors found a threshold shift (TS) of a harbor porpoise after exposing it to airgun noise (single pulse) with a received sound pressure level (SPL) at 200.2 dB (peak–to-peak) re 1 mPa, which corresponds to a sound exposure level of 164.5 dB re 1 mPa2 s after integrating exposure. NMFS currently uses the root-mean-square (rms) of received SPL at 180 dB and 190 dB re 1 mPa as the threshold above which permanent threshold shift (PTS) could occur for cetaceans and pinnipeds, respectively. Because the pipe-driving noise is a broadband impulse, one cannot directly extrapolate the equivalent of rms SPL from the reported peak-to-peak SPLs reported in Lucke et al. (2009). However, applying a conservative conversion factor of 16 dB for broadband signals from seismic surveys (Harris et al., 2001; McCauley et al., 2000) to correct for the difference between peak-to-peak levels reported in Lucke et al. (2009) and rms SPLs; the rms SPL for TTS would be approximately 184 dB re 1 mPa, and the received levels associated with PTS (Level A harassment) would be higher. This is still above the current 180 dB rms re 1 mPa threshold for injury. Yet, NMFS recognizes that the temporary threshold shift (TTS) of harbor porpoise is lower than other cetacean species empirically tested (Finneran et al., 2002; Finneran and Schlundt, 2010; Kastelein et al., 2012). NMFS considered this information in the notice of the proposed IHA (79 FR 36743, June 30, 2014). A Thompson et al. (1998) telemetry study on harbor (Phoca vitulina) and grey seals (Halichoerus grypus) suggested that avoidance and other behavioral reactions by individual seals to small airgun sources may at times be strong, but short-lived. The researchers conducted 1-hour controlled exposure experiments exposing individual seals fitted with telemetry devices to small airguns with a reported source level of 215–224 dB re 1 mPa (peak-to-peak) (Thompson et al., 1998; Gordon et al., 2003). The researchers measured dive behavior, swim speed heart rate and stomach temperature (indicator for feeding), but they did not measure hearing threshold shift in the animals. The researchers observed startle responses, decreases in heart rate, and temporary cessation of feeding. In six out of eight trials, harbor seals exhibited strong avoidance behaviors, and swam E:\FR\FM\30SEN3.SGM 30SEN3 tkelley on DSK3SPTVN1PROD with NOTICES3 58924 Federal Register / Vol. 79, No. 189 / Tuesday, September 30, 2014 / Notices rapidly away from the source (Thompson et al., 1998; Gordon et al., 2003). One seal showed no detectable response to the airguns, approaching within 300 m (984 ft) of the source (Gordon et al., 2003). However, they note that the behavioral responses were short-lived and the seals’ behavior returned to normal after the trials (Thompson et al., 1998; Gordon et al., 2003). The study does not discuss temporary threshold shift or permanent threshold shift in harbor seals and the estimated rms SPL for this survey is approximately 200 dB re 1 mPa, well above NMFS’s current 180 dB rms re 1 mPa threshold for injury for cetaceans and NMFS’ current 190 dB rms re 1 mPa threshold for injury for pinnipeds (accounting for the fact that the rms sound pressure level (in dB) is typically 16 dB less than the peak-to-peak level). In a study on the effect of nonimpulsive sound sources on marine mammal hearing, Kastak et al. (2008) exposed one harbor seal to an underwater 4.1 kHz pure tone fatiguing stimulus with a maximum received sound pressure of 184 dB re 1 mPa for 60 seconds (Kastak et al., 2008; Finneran and Branstetter, 2013). A second 60-second exposure resulted in an estimated threshold shift of greater than 50 dB at a test frequency of 5.8 kHz (Kastak et al., 2008). The seal recovered at a rate of ¥10 dB per log (min). However, 2 months post-exposure, the researchers observed incomplete recovery from the initial threshold shift resulting in an apparent permanent threshold shift of 7 to 10 dB in the seal (Kastak et al., 2008). NMFS notes that pipe-driving using an impact hammer sound is an impulsive source, and the context of Kastak et al. (2008) study is related to the effect of non-impulsive sounds on marine mammals. NMFS also considered two other Kastak et al. (1999, 2005) studies. Kastak et al. (1999) reported TTS of approximately 4–5 dB in three species of pinnipeds (harbor seal, California sea lion, and northern elephant seal) after underwater exposure for approximately 20 minutes to sound with frequencies ranging from 100 to 2,000 Hz at received levels 60 to 75 dB above hearing threshold. This approach allowed similar effective exposure conditions to each of the subjects, but resulted in variable absolute exposure values depending on subject and test frequency. Recovery to near baseline levels was reported within 24 hours of sound exposure. Kastak et al. (2005) followed up on their previous work, exposing the same test subjects to higher levels of sound for longer durations. The animals were exposed to octave-band VerDate Sep<11>2014 19:40 Sep 29, 2014 Jkt 232001 sound for up to 50 minutes of net exposure. The study reported that the harbor seal experienced TTS of 6 dB after a 25-minute exposure to 2.5 kHz of octave-band sound at 152 dB (183 dB SEL). The California sea lion demonstrated onset of TTS after exposure to 174 dB (206 dB SEL). NMFS acknowledges that PTS could occur if an animal experiences repeated exposures to TTS levels. However, an animal would need to stay very close to the sound source for an extended amount of time to incur a serious degree of PTS, which in this case would be highly unlikely due to the required mitigation measures in place to avoid Level A harassment and the expectation that a mobile marine mammal would generally avoid an area where received sound pulse levels exceed 160 dB re 1 mPa (rms) (review in Richardson et al., 1995; Southall et al., 2007). NMFS also considered recent studies by Kujawa and Liberman (2009) and Lin et al. (2011). These studies found that despite completely reversible threshold shifts that leave cochlear sensory cells intact, large threshold shifts (40 to 50 dB) could cause synaptic level changes and delayed cochlear nerve degeneration in mice and guinea pigs, respectively. NMFS notes that the high level of TTS that led to the synaptic changes shown in these studies is in the range of the high degree of TTS that Southall et al. (2007) used to calculate PTS levels. It is not known whether smaller levels of TTS would lead to similar changes. NMFS, however, acknowledges the complexity of noise exposure on the nervous system, and will re-examine this issue as more data become available. In contrast, a recent study on bottlenose dolphins (Schlundt, et al., 2013) measured hearing thresholds at multiple frequencies to determine the amount of TTS induced before and after exposure to a sequence of impulses produced by a seismic airgun. The airgun volume and operating pressure varied from 40 to 150 in3 and 1,000 to 2,000 psi, respectively. After three years and 180 sessions, the authors observed no significant TTS at any test frequency, for any combinations of airgun volume, pressure, or proximity to the dolphin during behavioral tests (Schlundt, et al., 2013). Schlundt et al. (2013) suggest that the potential for airguns (or in this case pipe-driving using an impact hammer) to cause hearing loss in dolphins is lower than previously predicted, perhaps as a result of the low-frequency content of airgun impulses compared to the highfrequency hearing ability of dolphins. Although the sounds from pipe-driving PO 00000 Frm 00012 Fmt 4701 Sfmt 4703 using an impact hammer are not equivalent to those produced by a seismic airgun, they are both considered impulse sounds. Comment 22: CBD states that NMFS must consider that even behavioral disturbance can amount to Level A take if it interferes with essential life functions. Response: NMFS notes that Level B take has been defined previously in this document and specifically relates to behavioral disturbance. NMFS acknowledge that behavioral harassment in certain contexts, or continued over long durations, may, in certain situations have impacts on health and fitness of marine mammals. The discussion of whether these more severse impacts on individuals (which could lead to population-level impacts) occur as a result of any particular project are included in the negligible impact analysis. They are also considered qualitatively in the development of mitigation measures, via consideration of biologically important areas in the analysis and for time-area closures, or other important factors. Please see the response to comment 21 for a discussion of studies addressing PTS (Level A harassment). Comment 23: CBD requested that NMFS use a behavioral threshold below 160 dB for estimating take based on results reported in Bain and Williams (2006), Clark and Gagnon (2006), MacLeod et al. (2006), Risch et al. (2012), and DeRuiter et al. (2013). Response: NMFS is constantly evaluating new science and how to best incorporate it into our decisions. This process involves careful consideration of new data and how it is best interpreted within the context of a given management framework. Each of these articles emphasizes the importance of context (e.g., behavioral state of the animals, distance from the sound source, etc.) in evaluating behavioral responses of marine mammals to acoustic sources. These papers and the studies discussed in the notice of the proposed IHA (79 FR 36743, June 30, 2014) note that there is variability in the behavioral responses of marine mammals to noise exposure. However, it is important to consider the context in predicting and observing the level and type of behavioral response to anthropogenic signals (Ellison et al., 2012). There are many studies showing that marine mammals do not show behavioral responses when exposed to multiple pulses at received levels at or above 160 dB re 1 mPa (e.g., Malme et al., 1983; Malme et al., 1984; Richardson et al., 1986; Akamatsu et al., 1993; Madsen E:\FR\FM\30SEN3.SGM 30SEN3 tkelley on DSK3SPTVN1PROD with NOTICES3 Federal Register / Vol. 79, No. 189 / Tuesday, September 30, 2014 / Notices and Mohl, 2000; Harris et al., 2001; Miller et al., 2005; and Weir, 2008). And other studies show that whales continue important behaviors in the presence of seismic pulses (e.g., Richardson et al., 1986; McDonald et al., 1995; Greene et al., 1999a, 1999b; Nieukirk et al., 2004; Smultea et al., 2004; Holst et al., 2005, 2006; Dunn and Hernandez, 2009). In a passive acoustic research program that mapped the soundscape in the North Atlantic, Clark and Gagnon (2006) reported that some fin whales stopped singing for an extended period starting soon after the onset of a seismic survey in the area. The study did not provide information on received levels or distance from the sound source. The authors could not determine whether or not the whales left the area ensonified by the survey, but the evidence suggests that most if not all singers remained in the area (Clark and Gagnon, 2006). Support for this statement comes from the fact that when the survey stopped temporarily, the whales resumed singing within a few hours and the number of singers increased with time (Clark and Gagnon, 2006). Also, they observed that one whale continued to sing while the seismic survey was actively operating (Figure 4; Clark and Gagnon, 2006). The authors conclude that there is not enough scientific knowledge to adequately evaluate whether or not these effects on singing or mating behaviors are significant or would alter survivorship or reproductive success (Clark and Gagnon, 2006). Thus, to address CBD’s concerns related to the results of this action, it is important to note that ExxonMobil’s action area is well away from any known breeding/ calving grounds for low frequency cetaceans, thereby reducing further the likelihood of causing an effect on marine mammals. MacLeod et al. (2006) discussed the possible displacement of fin and sei whales related to distribution patterns of the species during a large-scale seismic survey offshore the west coast of Scotland in 1998. The authors hypothesized about the relationship between the whale’s absence and the concurrent seismic activity, but could not rule out other contributing factors (Macleod et al., 2006; Parsons et al., 2009). NMFS would expect that marine mammals may briefly respond to underwater sound produced by the pipe-driving activities by slightly changing their behavior or relocating a short distance. Based on the best available information, NMFS expects short-term disturbance reactions that are confined to relatively small distances and durations (Thompson et al., 1998; VerDate Sep<11>2014 19:40 Sep 29, 2014 Jkt 232001 Thompson et al., 2013), with no longterm effects on recruitment or survival. Risch et al. (2012) documented reductions in humpback whale (Megaptera novaeangliae) vocalizations in the Stellwagen Bank National Marine Sanctuary concurrent with transmissions of the Ocean Acoustic Waveguide Remote Sensing (OAWRS) low-frequency fish sensor system at distances of 200 km (108 nmi) from the source. The recorded OAWRS produced series of frequency modulated pulses and the signal received levels ranged from 88 to 110 dB re 1 mPa (Risch et al., 2012). The authors hypothesize that individuals did not leave the area but instead ceased singing and noted that the duration and frequency range of the OAWRS signals (a novel sound to the whales) were similar to those of natural humpback whale song components used during mating (Risch et al., 2012). Thus, the novelty of the sound to humpback whales in the study area provided a compelling contextual probability for the observed effects (Risch et al., 2012). However, the authors did not state or imply that these changes had long-term effects on individual animals or populations (Risch et al., 2012), nor did they necessarily rise to the level of an MMPA take. Thus, to address CBD’s concerns related to the results of this study, NMFS again notes that the ExxonMobil’s action area is well away from any known breeding/calving grounds for low frequency cetaceans, thereby reducing further the likelihood of causing an effect on marine mammals. With repeated exposure to sound, many marine mammals may habituate to the sound at least partially (Richardson & Wursig, 1997). Bain and Williams (2006) examined the effects of a large airgun array (maximum total discharge volume of 1,100 in3) on six species in shallow waters off British Columbia and Washington: harbor seal, California sea lion (Zalophus californianus), Steller sea lion (Eumetopias jubatus), gray whale (Eschrichtius robustus), Dall’s porpoise (Phocoenoides dalli), and the harbor porpoise. Harbor porpoises showed ‘‘apparent avoidance response’’ at received levels less than 145 dB re 1 mPa at a distance of greater than 70 km (37.8 nmi) from the seismic source (Bain and Williams, 2006). However, the tendency for greater responsiveness by harbor porpoise is consistent with their relative responsiveness to boat traffic and some other acoustic sources (Richardson et al. 1995; Southall et al., 2007). In contrast, the authors reported that gray whales seemed to tolerate exposures to sound up to approximately 170 dB re 1 mPa PO 00000 Frm 00013 Fmt 4701 Sfmt 4703 58925 (Bain and Williams, 2006) and Dall’s porpoises occupied and tolerated areas receiving exposures of 170 to 180 dB re 1 mPa (Bain and Williams, 2006; Parsons et al., 2009). The authors observed several gray whales that moved away from the airguns toward deeper water where sound levels were higher due to propagation effects resulting in higher noise exposures (Bain and Williams, 2006). However, it is unclear whether their movements reflected a response to the sounds (Bain and Williams, 2006). Thus, the authors surmised that the gray whale data (i.e., voluntarily moving to areas where they are exposed to higher sound levels) are ambiguous at best because one expects the species to be the most sensitive to the low-frequency sound emanating from the airguns (Bain and Williams, 2006). DeRuiter et al. (2013) recently observed that beaked whales (considered a particularly sensitive species to sound) exposed to playbacks (i.e., simulated) of U.S. tactical midfrequency sonar from 89 to 127 dB re 1 mPa at close distances responded notably by altering their dive patterns. In contrast, individuals showed no behavioral responses when exposed to similar received levels from actual U.S. tactical mid-frequency sonar operated at much further distances (DeRuiter et al., 2013). As noted earlier, one must consider the importance of context (for example, the distance of a sound source from the animal) in predicting behavioral responses. Regarding the public comments submitted by Clark et al. (2012) in reference to NMFS’s use of the current acoustic exposure criteria; please refer to our earlier response to CBD. None of these studies on the effects of airgun noise on marine mammals point to any associated mortalities, strandings, or permanent abandonment of habitat by marine mammals. Bain and Williams (2006) specifically conclude that ‘‘. . . although behavioral changes were observed, the precautions utilized in the SHIPS survey did not result in any detectable marine mammal mortalities during the survey, nor were any reported subsequently by the regional marine mammal stranding network . . .’’ The ExxonMobil’s 160-dB threshold radius will likely not reach the threshold distances reported in these studies. Currently NMFS is in the process of revising its behavioral noise exposure criteria based on the best and most recent scientific information. NMFS will use these criteria to develop methodologies to predict behavioral responses of marine mammals exposed to sound associated with conductor pipe E:\FR\FM\30SEN3.SGM 30SEN3 tkelley on DSK3SPTVN1PROD with NOTICES3 58926 Federal Register / Vol. 79, No. 189 / Tuesday, September 30, 2014 / Notices installation activities (primary source impact hammer operations). Although using a uniform sound pressure level of 160-dB re 1 mPa for the onset of behavioral harassment for impulse noises may not capture all of the nuances of different marine mammal reactions to sound, it is an appropriate way to manage and regulate anthropogenic noise impacts on marine mammals until NMFS finalizes its acoustic guidelines. Comment 24: The CCC states that it applies a more conservative approach to permitting pile-driving in state waters and recommends using the modelgenerated 160-dB threshold as the initial exclusion zone that would trigger a shut-down of conductor pipe installation activities using the impact hammer if marine mammals are sighted by PSOs approaching or entering this area. The more protective 160 dB exclusion zone generated by modeling could subsequently be reduced if in-situ measurements taken during the sound source verification indicate that this is warranted. If use of the model-generated 160 dB threshold for this purpose was found to be infeasible, the CCC staff would recommend an alternate strategy of imposing an additional protective buffer to the model-generated 180 and 190 dB based exclusion zones. Response: NMFS expects that acoustic stimuli resulting from the impact hammer pipe-driving associated with the conductor pipe installation activities has the potential to result in Level B harassment of marine mammals. NMFS disagrees with the CCC’s recommendation to use the modelgenerated 160 dB threshold for underwater sounds as the initial exclusion zone that would trigger a shut-down for all marine mammals. Current NMFS practice, regarding exposure of marine mammals to highlevel underwater sounds is that cetaceans and pinnipeds exposed to impulsive sounds at or above 180 and 190 dB (rms), respectively, have the potential to be injured (i.e., Level A harassment). NMFS considers the potential for Level B (behavioral) harassment to occur when marine mammals are exposed to sounds below injury thresholds but at or above the 160 dB (rms) threshold for impulse sounds (e.g., impact pile-driving) and the 120 dB (rms) threshold for continuous noise (e.g., vibratory pile-driving). No vibratory pile-driving is planned for ExxonMobil’s planned activities in the Santa Barbara Channel. The CCC’s recommendation to use the estimated 160 dB exclusion zone as a trigger for shut-down is inconsistent with existing NMFS practice, and would VerDate Sep<11>2014 19:40 Sep 29, 2014 Jkt 232001 effectively expand the Level A harassment exclusion zone for cetaceans and pinnipeds. It should be noted that a much larger exclusion zone for triggering shut-downs of conductor pipe installation activities has the potential to result in operational delays which could extend impact hammer pipedriving time and/or result of losing a conductor pipe because successful completion of installation relies on consistent movement of the steel pipe through the bed sediment. NMFS also disagrees with the CCC’s recommendation regarding the use of a protective buffer to the model-generated 180 and 190 dB based exclusion zones. Monitoring will be performed during all impact hammer pipe-driving operations. Hydrophones will be deployed prior to the start of impact hammer pipe-driving the first pipe section. Data will be collected and analyzed upon completion of the conductor pipe’s last pipe section. Monitoring equipment will be redeployed prior to installation of the remaining five conductor pipes. Upon completion of the first conductor pipe, acoustic data will be retrieved from the near field (approximately 10 m) and far field (approximately 325 to 500 m) recorders, analyzed, and compared to the predicted rms radii distances for the buffer and exclusion zones. ExxonMobil will consult with NMFS prior to proceeding with conductor pipe installation activities in the event that acoustic field data indicate that predicted radii distances for the buffer and exclusion zones need to adjusted (either expanded or contracted). Distances will be recalculated using field data, and monitoring equipment will be redeployed at the corrected distances prior to installation of the remaining conductor pipes, following authorization from NMFS. The planned extended down period (non-hammering) between the completion of the first pipe installation and the start of the second pipe installation will be used to determine the actual size of buffer and exclusion zones (i.e., Level B and Level A harassment zones) to ensure that the radii estimated from acoustic modeling are not determined to be too small. NMFS and ExxonMobil acknowledges that in-situ measurements of the sound may not agree with the modeled acoustic data due to uncertainties and model limitations identified by the CCC; however, it is not possible to improve model accuracy without obtaining data from the field. For this reason, a sound source verification will be conducted during the driving of the impact hammer for the first conductor pipe. The data collected and analyzed will be used to establish more accurate buffer PO 00000 Frm 00014 Fmt 4701 Sfmt 4703 and exclusion zones, and refine the acoustic model, if needed, before installation of the second conductor pipe begins. Finally, the CCC cites IHAs issued previously by NMFS as precedent for its recommended approach to establishing exclusion zones using the 160 dB threshold as the trigger for implementing a shut-down procedure. Based on the citation provided by CCC (e.g., Naval Base Kitsap wharfs/piers, 2011 and 2014), it is not clear whether the CCC believes there are additional examples of precedent or what specific action is referred to for 2011 (no references are provided in the CCC’s letter, and NMFS issued two IHAs for construction activities at Naval Base Kitsap in 2011). However, referring to the 2014 example, in which NMFS issued an IHA to the Navy for take that could occur incidental to the third year of work associated with construction of a wharf (79 FR 43429, July 25, 2014), the exclusion zone was in fact established on the basis of in-situ sound source measurements, following initial definition based on modeling results. This approach was identical to that described by NMFS in our notice of the proposed IHA (79 FR 36743, June 30, 2014), and the example does not provide supportive precedent for the CCC’s recommendation. Effects Analyses Comment 25: The CBD states that NMFS’s evaluation in the notice of the proposed IHA (79 FR 36743, June 30, 2014) regarding the impacts from loss of prey on foraging are unknown; therefore, NMFS must get such data and analyze it to make its negligible impact determination. Response: NMFS disagrees with the CBD’s comment. The anticipated effects on marine mammal habitat, including effects on potential prey and potential foraging habitat were described in the notice of the proposed IHA (79 FR 36743, June 30, 2014). Secondary effects, such as impacts to prey and habitat, are very important to NMFS’s analysis and are considered in both the negligible impact analysis as well as qualitatively in the development of mitigation measures, via consideration of biologically important areas in the analysis and for time-area closures, or other important factors. NEPA Concerns Comment 26: The CBD states that NMFS must comply fully with the National Environmental Policy Act (NEPA). The CBD states that NMFS notes that it will complete an EA prior to its decision on the IHA. Based on E:\FR\FM\30SEN3.SGM 30SEN3 tkelley on DSK3SPTVN1PROD with NOTICES3 Federal Register / Vol. 79, No. 189 / Tuesday, September 30, 2014 / Notices multiple factors in NEPA’s regulations, that the proposed activities do constitute a significant impact, and NMFS should prepare a full EIS. The purpose and need for the action is unclear and unnecessary. The IHA application does not fully explain the need and purpose of the additional conductor pipes. The notice of the proposed IHA (79 FR 36743, June 30, 2014) states that the conductors are ‘‘to maintain current production levels from the existing platform.’’ This indicates that there is no need for the proposed action because maintenance of the current production levels should be able to be attained through the status quo. Response: In accordance with the National Environmental Policy Act (NEPA; 42 U.S.C. 4321 et seq.), NMFS completed an EA titled, ‘‘Environmental Assessment on the Issuance of an Incidental Harassment Authorization to ExxonMobil Production Company to Take Marine Mammals by Harassment Incidental to Conductor Pipe Installation Activities at Harmony Platform in the Santa Barbara Channel Offshore of California.’’ NMFS’s EA includes all required components, including a brief discussion of need for the proposed action, a listing of the alternatives to the proposed action, a description of the affected environment, a brief discussion of the environmental impacts of the proposed action and alternatives, and sufficient evidence and analysis for determining whether to prepare an EIS or a Finding of No Significant Impact (FONSI). NOAA Administrative Order (NAO) 216–6 contains criteria for determining the significance of the impacts of a proposed action. In addition, the Council on Environmental Quality (CEQ) regulations at 40 CFR 1508.27 state that the significance of an action should be analyzed both in terms of ‘‘context’’ and ‘‘intensity.’’ NMFS evaluated the significance of this action based on the NAO 216–6 criteria and CEQ’s context and intensity criteria. Based on this evaluation, NMFS determined that issuance of this IHA to ExxonMobil would not significantly impact the quality of the human environment and issued a FONSI. Accordingly, preparation of an EIS is not necessary. NMFS’s determination and evaluation of the NAO 216–6 criteria and CEQ’s context and intensity criteria are contained within the FONSI issued for this action, which is available on NMFS’s Web site at: https:// www.nmfs.noaa.gov/pr/permits/ incidental/. Comment 27: The CBD states NMFS must consider the additional suggested VerDate Sep<11>2014 19:40 Sep 29, 2014 Jkt 232001 mitigation measures as alternatives in its NEPA analysis. An environmental review must ‘‘inform decision-makers and the public of the reasonable alternatives which would avoid or minimize adverse impacts or enhance the quality of the human environment.’’ NMFS must ‘‘rigorously explore and objectively evaluate all reasonable alternatives, and for alternatives which were eliminated from detailed study, briefly discuss the reasons for their having been eliminated.’’ In addition, an agency must discuss measures designed to mitigate its action’s impact on the environment. Accordingly, time-area closures, larger exclusion zones, lowvisibility limitations, and noise reducing techniques should be considered in the range of alternatives. Response: In accordance with the National Environmental Policy Act (NEPA; 42 U.S.C. 4321 et seq.), NMFS completed an EA titled, ‘‘Environmental Assessment on the Issuance of an Incidental Harassment Authorization to ExxonMobil Production Company to Take Marine Mammals by Harassment Incidental to Conductor Pipe Installation Activities at Harmony Platform in the Santa Barbara Channel Offshore of California.’’ The EA analyzes the impacts on the human environment of the issuance of an IHA by NMFS to ExxonMobil for conductor pipe installation activities at Harmony Platform in Santa Barbara Channel. It includes an evaluation of two alternatives: (1) Issuance of an IHA with mitigation measures, and (2) A no action alternative (i.e., do not issue an IHA and do not conduct the seismic survey). The EA also included a section on alternatives that were considered but eliminated from further consideration. NMFS considered whether other alternatives could meet the purpose and need and support ExxonMobil’s conductor pipe installation activities. NMFS considered an alternative with additional mitigation measures; including the specific measures suggested by CBD, but eliminated that alternative from further consideration because the additional mitigation measures were considered not practicable or not likely to minimize adverse impacts. NMFS also considered an alternative that would allow for the issuance of an IHA with no required mitigation or monitoring but eliminated that alternative from further consideration, as it would not be in compliance with the MMPA and therefore would not meet the purpose and need. PO 00000 Frm 00015 Fmt 4701 Sfmt 4703 58927 The EA will be available on the NMFS ITA Web site at: https:// www.nmfs.noaa.gov/pr/permits/ incidental/. Comment 29: The CBD states that NMFS has a duty to consider the indirect impacts of its action. Indirect effects ‘‘are caused by the action and are later in time or farther removed in distance, but are still reasonably foreseeable.’’ Although the purpose of the conductor pipes is unclear, any changes in production, drilling, waste, techniques, or lifetime of the oil and gas operations at Harmony Platform must be fully disclosed and adequately evaluated. If, for example, the conductor pipes will be used for or enable hydraulic fracturing or other unconventional well stimulation techniques then the environmental effects must evaluated. Response: Changes to the production, drilling, waste, techniques, or lifetime of the oil and gas operations at Harmony Platform are regulated by the Bureau of Ocean Energy Management and the Bureau of Safety and Environmental Enforcement. As stated in the notice of the proposed IHA (79 FR 36743, June 30, 2014), ExxonMobil requested an IHA from NMFS to take marine mammals, by harassment, incidental to installing six conductor pipes at Harmony Platform. In accordance with the National Environmental Policy Act (NEPA; 42 U.S.C. 4321 et seq.), NMFS completed an EA to evaluate the environmental effects of authorizing the take of marine mammals incidental to ExxonMobil’s activities. The EA considers the direct, indirect, and cumulative impacts related to the issuance of an IHA authorizing the take of marine mammals incidental ExxonMobil’s activities. NMFS notes that all produced fluids from ExxonMobil’s offshore Santa Ynez Production Unit are routed to the onshore treating facilities located in Las Flores Canyon, where it is treated and re-routed via pipeline, and discharged under an existing Environmental Protection Agency National Pollutant Discharge Elimination System (NPDES) permit. ExxonMobil has not used hydraulic fracturing on any of the wells on the three platforms in the Santa Ynez Production Unit located offshore of California. ExxonMobil has not and does not plan to use hydraulic fracturing or other unconventional well techniques in its offshore operations. Comment 29: The CBD states that NMFS must also look at the cumulative effects (past, present, and reasonably foreseeable future actions) of the action. For example, the Santa Barbara Channel is a busy shipping lane which means that the cumulative effects of noise E:\FR\FM\30SEN3.SGM 30SEN3 58928 Federal Register / Vol. 79, No. 189 / Tuesday, September 30, 2014 / Notices tkelley on DSK3SPTVN1PROD with NOTICES3 pollution from ship traffic and ship strikes must be evaluated. Whales fleeing pile-driving activities may be forced into shipping lanes to continue their foraging. Additionally, hydraulic fracturing activities from offshore oil and gas platforms in the area threaten endangered species and marine mammals in numerous ways—from oil spills and vessel strikes to air and water pollution. More than half of the platforms in federal waters discharge their wastewater, which can include toxic fracking chemicals, into the ocean. Harmony Platform alone is permitted to discharge over 33,000 barrels of wastewater into the ocean each year. Response: The NMFS EA analyzes the effects of NMFS’s issuance of an IHA with mitigation and monitoring measures for the conductor pipe installation activities in light of other past, present, and reasonably foreseeable actions in the area including (1) other impact pipe-driving activities; (2) research activities; (3) military testing and training activities; (4) oil and gas activities; (5) vessel traffic, noise, and collisions; (6) commercial and recreational fishing; and (7) climate change. The EA concludes that the impacts of the issuance of an IHA for ExxonMobil’s proposed conductor pipe installation activities in the Santa Barbara Channel offshore of California are expected to be no more than minor and short-term with no potential to contribute to cumulatively significant impacts. NMFS notes that Harmony Platform is located on the coastal side of the shipping lane in Santa Barbara Channel, while foraging areas are concentrated on the seaward side of the shipping lane; thus the whales would not be forced into the area busy with vessel traffic to forage. The shipping channel is located 12 to 14 km (6.5 to 7.6 nmi) from the Harmony Platform, and underwater sounds are within normal ambient ranges at the platform (e.g., 120 dB). As stated previously in this document, ExxonMobil does not perform hydraulic fracturing at Harmony Platform or elsewhere offshore of California. All produced water, including any fluids that are produced through the wells, are treated at the Las Flores Canyon facility and discharged as permitted under the Clean Water Act. General Concerns Comment 30: Numerous private citizens, as supporters of SierraRise and Sierra Club, and the CBD, oppose the issuance of the IHA to ExxonMobil. They call on the government to stop destructive actions in the Santa Barbara Channel that lead to impairment, injury, VerDate Sep<11>2014 19:40 Sep 29, 2014 Jkt 232001 and death of marine mammals. ExxonMobil’s conductor pipe installation activities could lead to the death of many whales, otters, and more animals that are already threatened by toxic fracking fluids that have been dumped into their water. The commenters state that marine mammals deserve a safe, healthy ocean environment to live in, a healthy ocean is more important than more climatekilling offshore drilling. Response: As described in detail in the Federal Register notice for the proposed IHA (79 FR 36743, June 30, 2014), as well as in this document, NMFS anticipates only behavioral disturbance to occur during the conductor pipe installation activities. NMFS has determined that ExxonMobil’s conductor pipe installation activities will not cause injury, serious injury, or mortality to marine mammals managed under NMFS’s jurisdiction, and not takes by injury, serious injury, or mortality are authorized. Further, ExxonMobil is required to implement a number of mitigation and monitoring measures during the impact hammer pipe-driving activities, which are described below in the ‘‘Mitigation’’ and ‘‘Monitoring and Reporting’’ sections. NMFS has determined that the required mitigation measures provide the means of effecting the least practicable impact on marine mammal species or stocks and their habitat, paying particular attention to rookeries, mating grounds, and areas of similar significance. The sea otter is managed by the U.S. Fish and Wildlife Service. Comment 31: The CBD states that NMFS should consider the environmental impacts of the activity on nearby marine protected areas (MPAs), reserves, and the Channel Islands National Marine Sanctuary that are located in the vicinity of the conductor pipe installation activities. Response: NMFS has considered environmental impacts of the conductor pipe installation activities on nearby MPAs as well as the Channel Islands National Marine Sanctuary. Individual mainland MPAs in southern California include: Point Conception State Marine Reserve (SMR), Kashtayit State Marine Conservation Area (SMCA), Naples SMCA, Campus Point SMCA, Goleta Slough SMCA, Point Dume SMCA, Point Dume SMR, Point Vicente SMCA, Abalone Cove SMCA, Bolsa Chica Basin SMCA, Upper Newport Bay SMCA, Crystal Cove SMCA, Laguna Beach SMR, Laguna Beach SMCA, Dana Point SMCA, Batiquitos Lagoon SMCA, Swami’s SMCA, San Elijo Lagoon SMCA, San Diego-Scripps Coastal PO 00000 Frm 00016 Fmt 4701 Sfmt 4703 SMCA, Matlahuayl SMR, South La Jolla SMR, South La Jolla SMCA, Famosa Slough SMCA, Cabrillow SMR, and Tijuana River Mouth SMCA. Individual island MPAs include: Richardson Rock SMR and Federal MR, San Miguel Island Special Closure, Harris Point SMR and Federal MR, Judith Rock SMR, Carrington Point SMR, Skunk Point SMR, South Point SMR and Federal MR, Painted Cave SMCA, Gull Island SMR and Federal MR, Anacapa Island Special Closure, Anacapa Island SMR and Federal MR, Anacapa Island SMCA and Federal MCA, Footprint SMR and Federal MR, Begg Rock SMR, Santa Barbara Island MR and Federal MR, Arrow Point to Lion Head Point SMCA, Blue Cavern SMCA, Bird Rock SMCA, Long Point SMR, Casino Point SMCA, Lover’s Cover SMCA, Farnsworth Onshore SMCA, Farnsworth Offshore SMCA, and Cat Harbor SMCA. The closest MPAs, which are Naples SMCA and Point Conception SMR, are over 18.5 km (10 nmi) east-southeast and 27.8 km (15 nmi) west-northwest at its closest boundary to Harmony Platform, respectively. Sound levels generated during the planned conductor pipe installation activities will not have significant consequences on MPAs because all MPAs are a minimum of 18.5 km from the Harmony Platform and the platform is not in shallow water depths. The Channel Islands National Marine Sanctuary is about 25.9 km (14 nmi) southwest at its closest boundary to Harmony Platform. NMFS has contacted Channel Islands National Marine Sanctuary regarding ExxonMobil’s planned conductor pipe installation activities and the associated issuance of an IHA. NMFS has determined that a consultation under the National Marine Sanctuary Act is not necessary as the planned action is not anticipated to have impacts on sanctuary resources. Comment 32: The CBD states that noise from conductor pipe installation activities can impact EFH and NMFS must fully comply with its statutory obligation to consult on the impact of federal activities on essential fish habitat (EFH) under the MagnusonStevens Fishery Conservation and Management Act (MSA). The EFH consultation should include an evaluation of the effects of the action on EFH, proposed mitigation, and make conservation recommendations. Response: NMFS disagrees with the commenter’s assessment. NMFS’s issuance of an IHA and the mitigation and monitoring measures required by the IHA would not affect ocean and coastal habitat or EFH. Therefore, NMFS, Office of Protected Resources, E:\FR\FM\30SEN3.SGM 30SEN3 tkelley on DSK3SPTVN1PROD with NOTICES3 Federal Register / Vol. 79, No. 189 / Tuesday, September 30, 2014 / Notices Permits and Conservation Division determined that an EFH consultation is not required. Comment 33: The CBD states that NMFS must comply fully with the Endangered Species Act (ESA) and develop a robust Biological Opinion based on the best available science. The proposed conductor pipe installation activities may have harmful impacts on ESA-listed marine mammals (including North Pacific right, humpback, sei, fin, blue, and sperm whales, as well as southern sea otters and Guadalupe fur seals), which must be fully and accurately vetted through the consultation process. Accordingly, NMFS must complete consultation and obtain any take authorization before authorizing the proposed activities. They further urge NMFS to establish more stringent mitigation measures to avoid adverse impacts to ESA-listed species. Response: Section 7(a)(2) of the ESA requires that each federal agency insure that any action authorized, funded, or carried out by such agency is not likely to jeopardize the continued existence of any endangered or threatened species or result in the destruction or adverse modification of critical habitat of such species. Of the species of marine mammals that may occur in the action area, several are listed as endangered under the ESA, including the North Pacific right, Western North Pacific gray, humpback, sei, fin, blue, and sperm whales as well as the Guadalupe fur seal. Although critical habitat is designated for the North Pacific right whale, no critical habitat for North Pacific right whales occurs in the action area. The North Pacific right whale critical habitat in the Pacific Ocean can be found online at: https:// www.nmfs.noaa.gov/pr/pdfs/ criticalhabitat/ northpacificrightwhale.pdf. NMFS’s Office of Protected Resources, Permits and Conservation Division, initiated and engaged in formal consultation under section 7 of the ESA with NMFS’s West Coast Regional Office, Protected Resources Division, on the issuance of an IHA under section 101(a)(5)(D) of the MMPA for this activity. NMFS’s West Coast Regional Office, Protected Resources Division issued a Biological Opinion addressing the effects of the proposed actions on threatened and endangered species as well as designated critical habitat in September 2014. The Biological Opinion concluded that NMFS’s issuance of an IHA to ExxonMobil is not likely to jeopardize the existence of any threatened and endangered species and would have no effect on critical habitat. VerDate Sep<11>2014 19:40 Sep 29, 2014 Jkt 232001 NMFS’s West Coast Regional Office, Protected Resources Division, relied on the best scientific and commercial data available in conducting its analysis. NMFS’s Office of Protected Resources, Permits and Conservation Division also considered the conservation status and habitat of ESA-listed marine mammals. Included in the IHA are special procedures for situations or species of concern (see ‘‘Mitigation’’ section below). If a North Pacific right whale is visually sighted during the conductor pipe installation activities, the pipedriving activities must be shut-down regardless of the distance of the animal(s) to the sound source. The pipedriving will not resume firing until 30 minutes after the last documented whale visual sighting. Concentrations of humpback, sei, fin, blue, and/or sperm whales will be avoided if possible (i.e., exposing concentrations of animals to 160 dB), and the activities will be shutdown if necessary. For purposes of the conductor pipe installation activities, a concentration or group of whales will consist of three or more individuals visually sighted that do not appear to be traveling (e.g., feeding, socializing, etc.). NMFS’s West Coast Regional Office, Protected Resources Division, issued an Incidental Take Statement (ITS) incorporating the requirements of the IHA as Terms and Conditions of the ITS. Compliance with the ITS is likewise a mandatory requirement of the IHA. NMFS’s Office of Protected Resources, Permits and Conservation Division has determined that the mitigation measures required by the IHA provide the means of effecting the least practicable impact on species or stocks and their habitat, including ESA-listed species. Comment 34: The CBD states that NMFS must comply fully with the Coastal Zone Management Act (CZMA). The CZMA requires that applicants for federal permits to conduct an activity affecting a natural resource of the coastal zone of a state ‘‘shall provide in the application to the licensing or permitting agency a certification that the proposed activity complies with the enforceable policies of the state’s approved program and that such activity will be conducted in a manner consistent with the program.’’ CBD states that marine species that will be affected by the project are ‘‘natural resources’’ protected by California’s coastal management program, and that California should be given the opportunity to review the IHA for consistency with their coastal management programs. Response: As the lead federal agency for the IHA, NMFS considered whether the action would have effects on the PO 00000 Frm 00017 Fmt 4701 Sfmt 4703 58929 coastal resources of any state along the U.S. West Coast. As concluded in the notice of the proposed IHA (79 FR 36743, June 30, 2014), any potential impacts from the conductor pipe installation activities would mainly be to marine species in close proximity to the Harmony Platform and would be of a short duration and temporary in nature. The Harmony Platform is located at 34° 22′35.906″ North and 120°10′04.48″ West, which is located approximately 10 km (5.4 nmi) off the coast of California, in federal waters. NMFS discussed issuance of the IHA and ExxonMobil’s planned conductor pipe installation activities with the California Coastal Commission. Therefore, NMFS has concluded that we have met all of the responsibilities under the CZMA. Comment 35: The CBD is concerned that ExxonMobil is not in full compliance with the Outer Continental Shelf Lands Act (OCSLA). The CBD states that NMFS provided no support for its statement that the proposed conductor pipe installation activities are considered in the existing Development and Production Plan. Response: The OCSLA is administered by the Department of the Interior. NMFS does not have the regulatory authority to permit ExxonMobil’s activities under the OCSLA. As stated in the notice of the proposed IHA (79 FR 36743, June 30, 2014), ExxonMobil requested an IHA from NMFS to take marine mammals, by harassment, incidental to installing six conductor pipes at Harmony Platform in the Santa Barbara Channel. Consistent with its regulatory authority under the MMPA, NMFS determined that authorizing the take of small numbers of marine mammals by Level B harassment incidental to ExxonMobil’s activities would have a negligible impact on marine mammals species or stocks and would not have an unmitigable adverse impact on the availability of species or stocks for taking for subsistence uses, and prescribed the permissible methods of taking by harassment pursuant such activity and other means of effecting the least practicable impact on species or stocks and their habitat. Description of the Marine Mammals in the Area of the Specified Activity The marine mammals that generally occur in the planned action area belong to four taxonomic groups: mysticetes (baleen whales), odontocetes (toothed whales), pinnipeds (seals and sea lions), and fissipeds (sea otters). The marine mammal species that potentially occur within the Pacific Ocean in proximity to the action area in the Santa Barbara E:\FR\FM\30SEN3.SGM 30SEN3 58930 Federal Register / Vol. 79, No. 189 / Tuesday, September 30, 2014 / Notices Channel off the coast of California (ranging from Point Conception and south, including the entire Southern California Bight) include 31 species of cetaceans (whales, dolphins, and porpoises) and 6 species of pinnipeds. The southern sea otter (Enhydra lutris nereis) is listed as threatened under the ESA and is managed by the U.S. Fish and Wildlife Service and is not considered further in this IHA notice. Marine mammal species listed as threatened or endangered under the U.S. Endangered Species Act of 1973 that could potentially occur in the action area (ESA; 16 U.S.C. 1531 et seq.), include the North Pacific right (Eubalaena japonica), Western North Pacific population gray (Eschrichtius robustus), humpback (Megaptera novaeangliae), sei (Balaenoptera borealis), fin (Balaenoptera physalus), blue (Balaenoptera musculus), and sperm (Physeter macrocephalus) whale as well as the Guadalupe fur seal (Arctocephalus townsendi). Of those threatened and endangered species, the humpback, sei, fin, blue, and sperm whale are likely to be encountered in the action area. Cetaceans occur throughout the Santa Barbara Channel action area, including nearby the Harmony Platform, from the surf zone to open ocean environments beyond the Channel Islands. Distribution is influenced by a number of factors, but primary among these are patterns of major ocean currents, bottom relief, and sea surface temperature. These physical oceanographic conditions affect prey abundance, which may attract marine mammals during periods of high productivity, and vice versa. Water movement is near continuous, varying seasonally, and is generally greatest from late spring to early fall in response to varying wind stress. This phenomenon is much greater in the western Santa Barbara Channel. This near continuous movement of water from the ocean bottom to the surface creates a nutrientrich, highly productive environment for marine mammal prey (Jefferson et al., 2008). Most of the large cetaceans are migratory, but many small cetaceans do not undergo extensive migrations. Instead, they undergo local or regional dispersal, on a seasonal basis or in response to food availability. Population centers may shift on spatial scales exceeding 100 km (54 nmi) over small time scales (days or weeks) (Dailey and Bonnell, 1993). Systematic surveys (1991 to 1993, 1996, 2001, 2005) in the southern California region have been carried out via aircraft (Carretta and Forney, 1993) and vessel (Ferguson and Barlow, 2001; Barlow, 2003) by NMFS. In addition, a vessel survey in the U.S. Exclusive Economic Zone (EEZ), and out to 556 km (300.2 nmi) offshore of California, Oregon, and Washington, was conducted in the summer and fall of 2005 by NMFS (Forney, 2007). Many other regional surveys have also been conducted (Carretta, 2003). Becker (2007) analyzed data from vessel surveys conducted since 1986, and compiled marine mammal densities. There are 31 cetacean and 6 pinniped species with ranges that are known to occur in the Eastern North Pacific Ocean waters of the project area. These include the North Pacific right whale, dwarf sperm whale (Kogia sima), harbor porpoise (Phocoena phocoena), Steller sea lion (Eumatopias jubatus), and Guadalupe fur seal. However, these species are extremely rare, found in the Channel Islands, or are primarily found north or south of the Santa Barbara Channel, and are unlikely to be found in the action area. The harbor porpoise occurs north of Point Conception, California. Guadalupe fur seals are most common at Guadalupe Island, Mexico, which is their primary breeding ground (Melin and Delong, 1999). Although adult and juvenile males have been observed at San Miguel Island, California, since the mid-1960’s, and in the late 1990’s a pup was born on the islands (Melin and Delong, 1999), more recent sightings are extremely rare. These species are not considered further in this document. Table 4 (below) presents information on the occurrence, abundance, distribution, population status, and conservation status of the species of marine mammals that may occur in the project area during September to December 2014. TABLE 4—THE HABITAT, OCCURRENCE, RANGE, REGIONAL ABUNDANCE, AND CONSERVATION STATUS OF MARINE MAMMALS THAT MAY OCCUR IN OR NEAR THE PIPE INSTALLATION PROJECT AREA OFF THE COAST OF CALIFORNIA IN THE PACIFIC OCEAN [See text and Tables 3–1 in ExxonMobil’s IHA application for further details] Species Habitat Occurrence Range Best population estimate (Minimum) 1 ESA 2 NA (26)—Eastern North Pacific stock. EN ............................ D 19,126 (18,107)— Eastern North Pacific stock 155 (142)—Western North Pacific population. 1,918 (1,855)—California/Oregon/ Washington (CA/ OR/WA) stock. 478 (202)—CA/OR/ WA stock. DL—Eastern North Pacific stock EN— Western North Pacific population. NC—Eastern North Pacific stock D— Western North Pacific population EN ............................ D NL ............................ NC NA—No stock for CA/OR/WA. NL ............................ NC E:\FR\FM\30SEN3.SGM 30SEN3 MMPA 3 Mysticetes Coastal and pelagic Rare ......................... Coastal and shelf ..... Transient during seasonal migrations. Humpback whale (Megaptera novaeangliae). Pelagic, nearshore waters, and banks. Seasonal, sightings near northern Channel Islands. Cosmopolitan ........... Minke whale (Balaenoptera acutorostrata). tkelley on DSK3SPTVN1PROD with NOTICES3 North Pacific right whale (Eubalaena japonica). Gray whale (Eschrichtius robustus). Pelagic and coastal Less common in summer, small number around northern Channel Islands. Rare, infrequent summer off California. Tropics and sub-tropics to ice edges. Bryde’s whale Pelagic and coastal (Balaenoptera edeni). VerDate Sep<11>2014 19:40 Sep 29, 2014 Jkt 232001 PO 00000 Frm 00018 North Pacific Ocean between 20 to 60° North. North Pacific Ocean, Gulf of California to Arctic—Eastern North Pacific stock. Tropical and subtropical zones between 40° North and 40° South. Fmt 4701 Sfmt 4703 58931 Federal Register / Vol. 79, No. 189 / Tuesday, September 30, 2014 / Notices TABLE 4—THE HABITAT, OCCURRENCE, RANGE, REGIONAL ABUNDANCE, AND CONSERVATION STATUS OF MARINE MAMMALS THAT MAY OCCUR IN OR NEAR THE PIPE INSTALLATION PROJECT AREA OFF THE COAST OF CALIFORNIA IN THE PACIFIC OCEAN—Continued [See text and Tables 3–1 in ExxonMobil’s IHA application for further details] Species Habitat Occurrence Sei whale (Balaenoptera borealis). Primarily offshore, pelagic. Rare, infrequent summer off California. Fin whale (Balaenoptera physalus). Blue whale (Balaenoptera musculus). Continental slope, pelagic. Year-round presence Pelagic, shelf, coastal. Seasonal, arrive April to May, common late-summer to fall off Southern California. Range Best population estimate (Minimum) 1 ESA 2 Tropical to polar zones, favor midlatitude temperate areas. Tropical, temperate, and polar zones of all oceans. Tropical waters to pack ice edges. 126 (83)—Eastern North Pacific stock. EN ............................ D 3,051 (2,598)—CA/ OR/WA stock. EN ............................ D 1,647 (1,551)—Eastern North Pacific stock. EN ............................ D 971 (751)—CA/OR/ WA stock. EN ............................ D 579 (271)—CA/OR/ WA stock. NL ............................ NC NA—CA/OR/WA stock. NL ............................ NC 847 (466)—CA/OR/ WA stock. NL ............................ NC 6,590 (4,481)—CA/ OR/WA stock. 694 (389)— Mesoplodon spp. CA/OR/WA stock. NL ............................ NC NL ............................ NC 694 (389)— Mesoplodon spp. CA/OR/WA stock. NL ............................ NC 694 (389)— Mesoplodon spp. CA/OR/WA stock. NL ............................ NC 694 (389)— Mesoplodon spp. CA/OR/WA stock. NL ............................ NC 694 (389)— Mesoplodon spp. CA/OR/WA stock. NL ............................ NC 694 (389)— Mesoplodon spp. CA/OR/WA stock. NL ............................ NC 240 (162)—Eastern North Pacific Offshore stock 346 (346)—Eastern North Pacific Transient stock 354 (354)—West Coast Transient stock. NA—No stock for CA/OR/WA. NL ............................ NC NL ............................ NC 760 (465)—CA/OR/ WA stock. NL ............................ NC E:\FR\FM\30SEN3.SGM 30SEN3 MMPA 3 Odontocetes Sperm whale (Physeter macrocephalus). Pygmy sperm whale (Kogia breviceps). Pelagic, deep sea .... Dwarf sperm whale (Kogia sima). Deep waters off the shelf. Baird’s beaked whale (Berardius bairdii). Pelagic ..................... Cuvier’s beaked whale (Ziphius cavirostris). Blainville’s beaked whale (Mesoplodon densirostris). Pelagic ..................... Pelagic, slope .......... Pelagic ..................... Perrin’s beaked whale Pelagic ..................... (Mesoplodon perrini). Common year-round, Tropical waters to more likely in pack ice edges. waters >1,000 m. Seaward of 500 to Tropical to warm 1,000 m, Limited temperate zones sightings in South(temperate prefern California Bight. erence). Rare ......................... Tropical to warm temperate zones (warmer preference). Primarily along conti- North Pacific Ocean nental slope late and adjacent seas. spring to early fall. Possible year-round Cosmopolitan ........... occurrence. Rare, continental Temperate and tropslope region, genical waters worlderally seaward of wide. 500 to 1,000 m depth. Rare, continental North Pacific Ocean slope region, generally seaward of 500 to 1,000 m depth. Rare, continental Temperate and tropslope region, genical waters Eastern erally seaward of Pacific Ocean. 500 to 1,000 m depth. Rare, continental North Pacific Ocean slope region, generally seaward of 500 to 1,000 m depth. Rare, continental Temperate and tropslope region, genical waters Indoerally seaward of Pacific Ocean. 500 to 1,000 m depth. Rare, continental North Pacific Ocean slope region, generally seaward of 500 to 1,000 m depth. Varies on inter-anCosmopolitan ........... nual basis, likely in winter (January to February). Pelagic ..................... Stejneger’s beaked whale (Mesoplodon stejnegeri). Pelagic ..................... Ginkgo-toothed beaked whale (Mesoplodon ginkgodens). Pelagic ..................... Hubbs’ beaked (Mesoplodon carlhubbsi). Pelagic ..................... Killer whale (Orcinus orca). tkelley on DSK3SPTVN1PROD with NOTICES3 Lesser beaked whale (Mesoplodon peruvianis). Pelagic, shelf, coastal, pack ice. False killer whale (Pseudorca crassidens). Short-finned pilot whale (Globicephala macrorhynchus). Pelagic ..................... Rare ......................... Tropical to warm temperate zones. Pelagic, shelf, coastal. Uncommon, more common before 1982. Warm temperate to tropical waters, ∼50° North to 40° South. VerDate Sep<11>2014 19:40 Sep 29, 2014 Jkt 232001 PO 00000 Frm 00019 Fmt 4701 Sfmt 4703 58932 Federal Register / Vol. 79, No. 189 / Tuesday, September 30, 2014 / Notices TABLE 4—THE HABITAT, OCCURRENCE, RANGE, REGIONAL ABUNDANCE, AND CONSERVATION STATUS OF MARINE MAMMALS THAT MAY OCCUR IN OR NEAR THE PIPE INSTALLATION PROJECT AREA OFF THE COAST OF CALIFORNIA IN THE PACIFIC OCEAN—Continued [See text and Tables 3–1 in ExxonMobil’s IHA application for further details] Species Habitat Occurrence Range Best population estimate (Minimum) 1 ESA 2 Bottlenose dolphin (Tursiops truncatus). Offshore, inshore, coastal, estuaries. Tropical and temperate waters between 45° North and South. 1,006 (684)—CA/OR/ WA Offshore stock 323 (290)—California Coastal stock. NL ............................ NC Striped dolphin (Stenella coeruleoalba). Short-beaked common dolphin (Delphinus delphis). Long-beaked common dolphin (Delphinus capensis). Off continental shelf Offshore stock— Year-round presence Coastal stock—Limited, small population within 1 km of shore. Occasional visitor ..... Tropical to temperate waters, 50° North to 40° South. Tropical to temperate waters of Atlantic and Pacific Ocean. Nearshore and tropical waters. 10,908 (8,231)—CA/ OR/WA stock. NL ............................ NC 411,211 (343,990)— CA/OR/WA stock. NL ............................ NC 107,016 (76,224)— California stock. NL ............................ NC Pacific white-sided dolphin (Lagenorhynchus obliquidens). Northern right whale dolphin (Lissodelphis borealis). Risso’s dolphin (Grampus griseus). Offshore, slope ........ Temperate waters of North Pacific Ocean. 26,930 (21,406)— CA/OR/WA, Northern and Southern stock. 8,334 (6,019)—CA/ OR/WA stock. NL ............................ NC NL ............................ NC 6,272 (4,913)—CA/ OR/WA stock. NL ............................ NC Dall’s porpoise (Phocoenoides dalli). Shelf, slope, offshore Continental slope and outer shelf of tropical to temperate waters. North Pacific Ocean, 30 to 62° North. 42,000 (32,106)— CA/OR/WA stock. NL ............................ NC Harbor porpoise (Phocoena phocoena). Coastal and inland waters. Shallow temperate to sub-polar waters of Northern Hemisphere. NA ............................ NL ............................ NC 296,750 (153,337)— U.S. stock. NL ............................ NC 49,685 (45,916)— Western stock 58,334 to 72,223 (52,847)—Eastern stock. 30,196 (26,667)— California stock. EN—Western stock DL—Eastern stock. D NL ............................ NC Eastern and Central North Pacific Ocean—Alaska to Mexico. 124,000 (74,913)— California breeding stock. NL ............................ NC North Pacific Ocean—Mexico to Japan. 12,844 (6,722)—California stock. NL ............................ NC California to Baja California, Mexico. 7,408 (3,028)—Mexico to California stock. T ............................... D E:\FR\FM\30SEN3.SGM 30SEN3 Shelf, pelagic, seamounts. Inshore ..................... Pelagic ..................... Deep water, seamounts. Common, more abundant in summer. Common, more inshore distribution, year-round presence. Common, yearround, more abundant November to April. Common, more abundant November to April. Common, present in summer, more abundant November to April. Common, more abundant November to April. AK to Point Conception, CA. North Pacific Ocean, 30 to 50° North. MMPA 3 Pinnipeds Coastal, shelf ........... Pacific harbor seal (Phoca vitulina richardii). tkelley on DSK3SPTVN1PROD with NOTICES3 California sea lion (Zalophus californianus). Steller sea lion (Eumetopias jubatus). Common, Channel Island breeding sites in summer. Rare ......................... Eastern North Pacific Ocean—Alaska to Mexico. North Pacific Ocean—Central California to Korea. Coastal ..................... Common, haul-outs and rookeries in Channel Islands, bulk of stock north of Point Conception. Northern elephant seal Coastal, pelagic Common, haul-outs (Mirounga when not migrating. and rookeries in angustirostris). Channel Islands, December to March and April to August, spend 8 to 10 months at sea. Northern fur seal Pelagic, offshore ...... Common, small pop(Callorhinus ursinus). ulation breeds on San Miguel Island May to October. Guadalupe fur seal Coastal, shelf ........... Rare, observed in (Arctocephalus Channel Islands. townsendi). Coastal temperate to polar regions in Northern Hemisphere. VerDate Sep<11>2014 Coastal, shelf ........... 19:40 Sep 29, 2014 Jkt 232001 PO 00000 Frm 00020 Fmt 4701 Sfmt 4703 58933 Federal Register / Vol. 79, No. 189 / Tuesday, September 30, 2014 / Notices TABLE 4—THE HABITAT, OCCURRENCE, RANGE, REGIONAL ABUNDANCE, AND CONSERVATION STATUS OF MARINE MAMMALS THAT MAY OCCUR IN OR NEAR THE PIPE INSTALLATION PROJECT AREA OFF THE COAST OF CALIFORNIA IN THE PACIFIC OCEAN—Continued [See text and Tables 3–1 in ExxonMobil’s IHA application for further details] Species Habitat Occurrence Range Best population estimate (Minimum) 1 ESA 2 2,826 (2,723)—California stock. T ............................... MMPA 3 Fissipeds Southern sea otter (Enhydra lutris nereis). Coastal ..................... Mainland coastline from San Mateo County to Santa Barbara County, CA San Nicolas Island. North Pacific Rim— Japan to Mexico. D NA = Not available or not assessed. 1 NMFS Marine Mammal Stock Assessment Reports. 2 U.S. Endangered Species Act: EN = Endangered, T = Threatened, DL = Delisted, and NL = Not listed. 3 U.S. Marine Mammal Protection Act: D = Depleted, S = Strategic, and NC = Not Classified. Further detailed information regarding the biology, distribution, seasonality, life history, and occurrence of these marine mammal species in the planned project area can be found in sections 3 and 4 of ExxonMobil’s IHA application. NMFS has reviewed these data and determined them to be the best available scientific information for the purposes of the IHA. tkelley on DSK3SPTVN1PROD with NOTICES3 Potential Effects of the Specified Activity on Marine Mammals This section includes a summary and discussion of the ways that the types of stressors associated with the specified activity (e.g., impact hammer pipedriving) have been observed to impact marine mammals. This discussion may also include reactions that we consider to rise to the level of a take and those that we do not consider to revise to the level of take (for example, with acoustics), we may include a discussion of studies that showed animals not reacting at all to sound or exhibiting barely measureable avoidance). This section is intended as a background of potential effects and does not consider either the specific manner in which this activity will be carried out or the mitigation that will be implemented, and how either of those will shape the anticipated impacts from this specific activity. The ‘‘Estimated Take by Incidental Harassment’’ section later in this document will include a quantitative analysis of the number of individuals that are expected to be taken by this activity. The ‘‘Negligible Impact Analysis’’ section will include the analysis of how this specific activity will impact marine mammals and will consider the content of this section, the ‘‘Estimated Take by Incidental Harassment’’ section, the ‘‘Mitigation’’ section, and the ‘‘Anticipated Effects on Marine Mammal Habitat’’ section to draw conclusions regarding the likely VerDate Sep<11>2014 19:40 Sep 29, 2014 Jkt 232001 impacts of this activity on the reproductive success or survivorship of individuals and from that on the affected marine mammal populations or stocks. When considering the influence of various kinds of sound on the marine environment, it is necessary to understand that different kinds of marine life are sensitive to different frequencies of sound. Based on available behavioral data, audiograms have been derived using auditory evoked potentials, anatomical modeling, and other data, Southall et al. (2007) designate ‘‘functional hearing groups’’ for marine mammals and estimate 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 (13 species of mysticetes): functional hearing is estimated to occur between approximately 7 Hz and 30 kHz; • Mid-frequency cetaceans (32 species of dolphins, six species of larger toothed whales, and 19 species of beaked and bottlenose whales): functional hearing is estimated to occur between approximately 150 Hz and 160 kHz; • High-frequency cetaceans (eight species of true porpoises, six species of river dolphins, Kogia spp., the franciscana (Pontoporia blainvillei), and four species of cephalorhynchids): functional hearing is estimated to occur between approximately 200 Hz and 180 kHz; and • Phocid pinnipeds in water: functional hearing is estimated to occur between approximately 75 Hz and 100 kHz; PO 00000 Frm 00021 Fmt 4701 Sfmt 4703 • Otariid pinnipeds in water: functional hearing is estimated to occur between approximately 100 Hz and 40 kHz. As mentioned previously in this document, 32 marine mammal species managed under NMFS jurisdiction (28 cetacean and 4 pinniped species) are likely to occur in the action area. Of the 28 cetacean species likely to occur in ExxonMobil’s action area, 7 are classified as low-frequency cetaceans (i.e., gray, humpback, minke, Bryde’s, sei, fin, and blue whale), 19 are classified as mid-frequency cetaceans (i.e., sperm, Baird’s beaked, Cuvier’s beaked, Blainville’s beaked, Perrin’s beaked, Lesser beaked, Stejneger’s beaked, Ginkgo-toothed beaked, Hubb’s beaked, killer, false killer, and shortfinned pilot whale, as well as bottlenose, striped, short-beaked common, long-beaked common, Pacific white-sided, northern right whale, and Risso’s dolphin), 2 are classified as high-frequency cetaceans (i.e., pygmy sperm whale and Dall’s porpoise), 2 are classified as phocids (i.e., harbor and northern elephant seal), and 2 are classified as otariid pinnipeds (i.e., California sea lion and northern fur seal) (Southall et al., 2007). A species’ functional hearing group is a consideration when we analyze the effects of exposure to sound on marine mammals. Current NMFS practice, regarding exposure of marine mammals to highlevel underwater sounds is that cetaceans and pinnipeds exposed to impulsive sounds at or above 180 and 190 dB (rms), respectively, have the potential to be injured (i.e., Level A harassment). NMFS considers the potential for Level B (behavioral) harassment to occur when marine mammals are exposed to sounds below injury thresholds but at or above the 160 dB (rms) threshold for impulse sounds E:\FR\FM\30SEN3.SGM 30SEN3 58934 Federal Register / Vol. 79, No. 189 / Tuesday, September 30, 2014 / Notices (e.g., impact pile-driving) and the 120 dB (rms) threshold for continuous noise (e.g., vibratory pile-driving). No vibratory pile-driving is planned for ExxonMobil’s planned activities in the Santa Barbara Channel. Current NMFS practice, regarding exposure of marine mammals to high-level in-air sounds, as a threshold for potential Level B harassment, is at or above 90 dB re 20 mPa for harbor seals and at or above 100 dB re 20 mPa for all other pinniped species (Lawson et al., 2002; Southall et al., 2007). NMFS has not established a threshold for Level A harassment for marine mammals exposed to in-air noise; however, Southall et al. (2007) recommends 149 dB re 20 mPa (peak) (flat) as the potential threshold for injury from in-air noise for all pinnipeds. Acoustic stimuli generated by the conductor pipe installation activities, which introduce sound into the marine environment and in-air, may have the potential to cause Level B harassment of marine mammals in the action area. The effects of sounds from impact hammer pile-driving activities might include one or more of the following: tolerance, masking of natural sounds, behavioral disturbance, temporary or permanent hearing impairment, or non-auditory physical or physiological effects (Richardson et al., 1995; Gordon et al., 2004; Nowacek et al., 2007; Southall et al., 2007). Permanent hearing impairment, in the unlikely event that it occurred, will constitute injury, but temporary threshold shift (TTS) is not an injury (Southall et al., 2007). Although the possibility cannot be entirely excluded, it is unlikely that the planned project will result in any cases of temporary or permanent hearing impairment, or any significant nonauditory physical or physiological effects. Based on the available data and studies described here, some behavioral disturbance is expected. The notice of the proposed IHA (79 FR 36743, June 30, 2014) included a discussion of the effects of impact hammer pile-driving on mysticetes, odontocetes, and pinnipeds including tolerance, masking, behavioral disturbance, hearing impairment, other non-auditory physical effects, and airborne sound effects. NMFS refers readers to that document, ExxonMobil’s IHA application and addendum and NMFS’s EA for additional information on the behavioral reactions (or lack thereof) by all types of marine mammals to pile-driving activities. Anticipated Effects on Marine Mammal Habitat, Fish, and Invertebrates NMFS included a detailed discussion of the potential effects of this action on marine mammal habitat, including anticipated effects on potential prey and anticipated effects on potential foraging habitat in the notice of the proposed IHA (79 FR 36743, June 30, 2014). The conductor pipe installation activities will not result in any permanent impact on habitats used by the marine mammals in the action area, including the food sources they use (i.e., fish and invertebrates), and there will be not physical damage to any habitat. While NMFS anticipates that the specified activity may result in marine mammals avoiding certain areas due to temporary ensonification, this impact to habitat is temporary and inconsequential, which was considered in further detail in the notice of the proposed IHA (79 FR 36743, June 30, 2014), as behavioral modification. The main impact associated with the activity will be temporarily elevated noise levels and the associated direct effects on marine mammals. Mitigation In order to issue an Incidental Take Authorization (ITA) under section 101(a)(5)(D) of the MMPA, NMFS must set forth the permissible methods of taking pursuant to such activity, and other means of effecting the least practicable impact on such species or stock and its habitat, paying particular attention to rookeries, mating grounds, and areas of similar significance, and the availability of such species or stock for taking for certain subsistence uses (where relevant). ExxonMobil incorporated a suite of appropriate mitigation measures into its project description (see Section 11 of the IHA application). NMFS reevaluated these mitigation measures after receiving public comments on the notice of the proposed IHA. To reduce the potential for disturbance from acoustic stimuli associated with the proposed activities, ExxonMobil and/or its designees will implement the following mitigation measures for marine mammals: (1) Buffer and exclusion zones around the sound source; (2) Hours of operation; (3) Shut-down procedures; (4) Ramp-up procedures; and Special procedures for situations or species of concern. Exclusion Zones—ExxonMobil uses radii to designate exclusion and buffer zones and to estimate take for marine mammals. Table 5 (see below) shows the distances at which one will expect marine mammal exposures to three received sound levels (160, 180, and 190 dB) from the impact hammer. The 180 and 190 dB level shut-down criteria are applicable to cetaceans and pinnipeds, respectively, as specified by NMFS (2000). ExxonMobil used these levels to establish the exclusion and buffer zones. TABLE 5—MODELED MAXIMUM DISTANCES TO WHICH IN-WATER SOUND LEVELS ≥190, 180 AND 160 dB re 1 μPa (rms) AND IN-AIR SOUND LEVELS ≥90 (FOR HARBOR SEALS) AND 100 dB re 20 μPa (rms) (FOR ALL OTHER PINNIPEDS) COULD BE RECEIVED DURING THE IMPACT HAMMER PILE-DRIVING ACTIVITIES (BASED ON MAXIMUM HAMMER ENERGY OF 90 KJ) IN THE SANTA BARBARA CHANNEL OFF THE COAST OF CALIFORNIA Water depth (m) Source Predicted RMS radii distances (m) for in-water pile-driving Modeled RMS radii distances (m) for in-air pile-driving 160 dB 180 dB 90 dB 190 dB 100 dB 325 (1,066.3 ft) 10 (32.8 ft) 3.5 (11.5 ft) 123 (403.5 ft) 41 (134.5 ft) tkelley on DSK3SPTVN1PROD with NOTICES3 90 kJ Impact Hammer Pile-Driver ........... 366 Based on the modeling, exclusion zones (for triggering a shut-down) for Level A harassment will be established for cetaceans and pinnipeds at 3.5 m (11.5 ft) and 10 m (32.8 ft) from the conductor pipe sound source, respectively. These shut-down zones will be monitored by a dedicated PSO. If the PSO detects a marine mammal(s) within or about to enter the appropriate exclusion zone, the pile-driving activities will be shut-down VerDate Sep<11>2014 19:40 Sep 29, 2014 Jkt 232001 PO 00000 Frm 00022 Fmt 4701 Sfmt 4703 immediately. If marine mammals are present within the shut-down zone before impact pile-driving activities begin, start of operations will be delayed until the exclusion zones are clear for at least 30 minutes. If marine mammals E:\FR\FM\30SEN3.SGM 30SEN3 tkelley on DSK3SPTVN1PROD with NOTICES3 Federal Register / Vol. 79, No. 189 / Tuesday, September 30, 2014 / Notices appear in the shut-down zone during pile-driving activities, the PSO will instruct the hammer operator to halt all operations in a safe, but immediate manner. Pile-driving activities will only resume once the exclusion zone has been cleared for at least 30 minutes. In the unlikely event that the marine mammal enters the exclusion zone during pile-driving activities, the exposure and behaviors will be documented and reported by the PSO and NMFS will be contacted within 24 hours. A non-PSO safety spotter will also be assigned to the lower deck observation area. All personnel operating at the lower observation levels will be required to wear appropriate personal protective equipment. Hours of Operation—The planned activities will be conducted on a continual 24-hour basis; therefore, some of the 2.5 to 3.3 hours of active impact pile-driving periods will be expected to occur during non-daylight hours. To facilitate visual monitoring during nondaylight hours, the exclusion zones will be illuminated to allow more effective viewing by the PSO. Lighting will not be expected to attract marine mammals. The areas where the exclusion zones occur fall within the jacket structure of the platform, and therefore could be easily illuminated by lights and monitored during non-daylight hours. For the buffer zone, which will extend out to 325 m (1,066.3 ft) from the conductor pipe, PSOs will be stationed on an upper deck of the Harmony Platform to monitor for marine mammals during the pile-driving activities. During non-daylight hours, PSOs will utilize night-vision devices and other appropriate equipment to monitor marine mammals. If nighttime visual aids are insufficient, ExxonMobil plans to use daytime visual counts of marine mammals as an estimate of the number of marine mammals present during non-daylight hours (within a 24hour period), noting that diurnal activities for most marine mammals are expected to vary somewhat. Shut-down Procedures—ExxonMobil will shut-down the operating hammer if a marine mammal is detected outside the exclusion zone, and the sound source will be shut-down before the animal is within the exclusion zone. Likewise, if a marine mammal is already within the exclusion zone when first detected, the sound source will be shutdown immediately. Following a shut-down, ExxonMobil will not resume pile-driving activities until the marine mammal has cleared the exclusion zone. ExxonMobil will consider the animal to have cleared the exclusion zone if: VerDate Sep<11>2014 19:40 Sep 29, 2014 Jkt 232001 • A PSO has visually observed the animal leave the exclusion zone, or • A PSO has not sighted the animal within the exclusion zone for 15 minutes for species with shorter dive durations (i.e., small odontocetes and pinnipeds), or 30 minutes for species with longer dive durations (i.e., mysticetes and large odontocetes, including sperm, pygmy and dwarf sperm, killer, and beaked whales). All visual monitoring will be conducted by qualified PSOs. Visual monitoring will be conducted continuously during active pile-driving activities. PSOs will not have any tasks other than visual monitoring and will conduct monitoring from the best vantage point(s) practicable (e.g., on the Harmony Platform or other suitable location) that provides 360° visibility of the Level A harassment exclusion zones and Level B harassment buffer zone, as far as possible. The PSO will be in radio communication with the hammer operator during pile-driving activities, and will call for a shut-down in the event a pinniped or cetacean appears to be headed toward its respective exclusion zone for cetaceans and pinnipeds. Ramp-up Procedures—Ramp-up (sometimes referred to as a ‘‘soft-start’’) of the impact hammer provides a gradual increase in sound levels until the full sound level is achieved. The purpose of a ramp-up is to ‘‘warn’’ marine mammals in the vicinity of the impact hammer and to provide the time for them to leave the area avoiding any potential injury or impairment of their hearing abilities. A ramp-up consists of an initial set of three strikes from the impact hammer at 40% energy, followed by a 30-second waiting period, then two subsequent three strike sets. The buffer zone will be monitored by PSOs beginning 30 minutes before piledriving activities, during pile-driving, and for 30 minutes after pile-driving stops. During ramp-up, the PSOs will monitor the exclusion zone, and if marine mammals are sighted, a shutdown will be implemented. If the complete exclusion zone has not been visible for at least 30 minutes prior to the start of operations in either daylight or nighttime, ExxonMobil will not commence the ramp-up. ExxonMobil will not initiate a ramp-up of the impact hammer if a marine mammal is sighted within or near the applicable exclusion zones during the day or close to the Harmony Platform at night. Special Procedures for Situations of Species of Concern—It is unlikely that a North Pacific right whale will be encountered during the conductor pipe PO 00000 Frm 00023 Fmt 4701 Sfmt 4703 58935 installation activities, but if so, the pipedriving activities will be shut-down immediately if one is visually sighted at any distance from the Harmony Platform because of its rarity and conservation status. The pipe-driving activities shall not resume (with rampup) until 30 minutes after the last documented North Pacific right whale visual sighting. Concentrations of humpback, sei, fin, blue and/or sperm whales shall be avoided if possible (i.e., exposing concentrations of animals to 160 dB), and the sound source shall be shut-down if necessary. For purposes of this planned conductor pipe installation activities, a concentration or group of whales will consist of three or more individuals visually sighted that do not appear to be traveling (e.g., feeding, socializing, etc.). Oil Spill Plan—ExxonMobil has developed an Oil Spill Response Plan and it is on file with BOEM. Mitigation Conclusions NMFS has carefully evaluated the applicant’s mitigation measures and has considered a range of other measures in the context of ensuring that NMFS prescribes the means of effecting the least practicable impact on the affected marine mammal species and stocks and their habitat. NMFS’s evaluation of potential measures included consideration of the following factors in relation to one another: (1) The manner in which, and the degree to which, the successful implementation of the measure is expected to minimize adverse impacts to marine mammals; (2) The proven or likely efficacy of the specific measure to minimize adverse impacts as planned; and (3) The practicability of the measure for applicant implementation, including consideration of personnel safety, practicality of implementation, and impact on the effectiveness of the activity. Any mitigation measure(s) prescribed by NMFS should be able to accomplish, have a reasonable likelihood of accomplishing (based on current science), or contribute to the accomplishment of one or more of the general goals listed below: (1) Avoidance or minimization of injury or death of marine mammals wherever possible (goals 2, 3, and 4 may contribute to this goal). (2) A reduction in the numbers of marine mammals (total number or number at biologically important time or location) exposed to received levels of hammer pile-driving, or other activities expected to result in the take of marine mammals (this goal may E:\FR\FM\30SEN3.SGM 30SEN3 58936 Federal Register / Vol. 79, No. 189 / Tuesday, September 30, 2014 / Notices tkelley on DSK3SPTVN1PROD with NOTICES3 contribute to 1, above, or to reducing harassment takes only). (3) A reduction in the number of times (total number or number at biologically important time or location) individuals will be exposed to received levels of hammer pile-driving, or other activities expected to result in the take of marine mammals (this goal may contribute to 1, above, or to reducing harassment takes only). (4) A reduction in the intensity of exposures (either total number or number at biologically important time or location) to received levels of hammer pile-driving, or other activities expected to result in the take of marine mammals (this goal may contribute to a, above, or to reducing the severity of harassment takes only). (5) Avoidance of minimization of adverse effects to marine mammal habitat, paying special attention to the food base, activities that block or limit passage to or from biologically important areas, permanent destruction of habitat, or temporary destruction/ disturbance of habitat during a biologically important time. (6) For monitoring directly related to mitigation—an increase in the probability of detecting marine mammals, thus allowing for more effective implementation of the mitigation. Based on NMFS’s evaluation of the applicant’s measures, as well as other measures considered by NMFS or recommended by the public, NMFS has determined that the mitigation measures provide the means of effecting the least practicable impact on marine mammal species or stocks and their habitat, paying particular attention to rookeries, mating grounds, and areas of similar significance. Monitoring and Reporting In order to issue an ITA for an activity, section 101(a)(5)(D) of the MMPA states that NMFS must 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 will 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 action area. ExxonMobil submitted a marine mammal monitoring plan as part of the IHA application. It can be found in Section 13 of the IHA application. The plan may be modified or supplemented based on comments or new information VerDate Sep<11>2014 19:40 Sep 29, 2014 Jkt 232001 received from the public during the public comment period. Monitoring measures prescribed by NMFS should accomplish one or more of the following general goals: (1) An increase in the probability of detecting marine mammals, both within the mitigation zone (thus allowing for more effective implementation of the mitigation) and in general to generate more data to contribute to the analyses mentioned below; (2) An increase in our understanding of how many marine mammals are likely to be exposed to levels of sound from impact hammer pile-driving activities that we associate with specific adverse effects, such as behavioral harassment, TTS or PTS; (3) An increase in our understanding of how marine mammals respond to stimuli expected to result in take and how anticipated adverse effects on individuals (in different ways and to varying degrees) may impact the population, species, or stock (specifically through effects on annual rates of recruitment or survival) through any of the following methods: • Behavioral observations in the presence of stimuli compared to observations in the absence of stimuli (need to be able to accurately predict received level, distance from source, and other pertinent information); • Physiological measurements in the presence of stimuli compared to observations in the absence of stimuli (need to be able to accurately predict receive level, distance from the source, and other pertinent information); • Distribution and/or abundance comparisons in times or areas with concentrated stimuli versus times or areas without stimuli; (4) An increased knowledge of the affected species; and (5) An increase in our understanding of the effectiveness of certain mitigation and monitoring measures. Monitoring ExxonMobil will conduct to sponsor marine mammal monitoring during the conductor pipe installation activities, in order to implement the mitigation measures that require real-time monitoring, and to satisfy the anticipated monitoring requirements of the IHA. ExxonMobil’s ‘‘Monitoring Plan’’ is described below this section. ExxonMobil understand that this monitoring plan will be subject to review by NMFS and that refinements may be required. Two main types of monitoring will be performed for this planned project: (1) In-situ measurement of sound pressure levels; and (2) visual observations of the PO 00000 Frm 00024 Fmt 4701 Sfmt 4703 number and type of marine mammals that enter sound exposure zones. In-situ acoustic data will be used to validate model predictions of sound pressure levels near and with distance from the conductor pipe sound source, including the predicted maximum distances for the buffer and exclusion zones. If measured results differ from modeled results, measured data will be used to revise buffer and exclusion zone boundaries to reflect actual conditions during planned project activities. Data from visual monitoring will be used to validate take estimate calculations. Acoustic Monitoring Acoustic monitoring using hydrophones and microphones will be conducted to obtain and validate modeled in-water and in-air sound levels during the pipe-driving activities. Each hydrophone (in-water) and microphone (in-air) will be calibrated following the manufacturer’s recommendations prior to the start of the planned project and checked for accuracy and precision at the end of the data collection for each conductor pipe or as practical during conductor pipe installation activities. Environmental data will be collected to supplement the acoustic monitoring and include: wind speed and direction, air temperature, humidity, near-surface water temperature, weather conditions, and other appropriate factors that could contribute to influencing either in-air or in-water sound transmission levels. Prior to deploying monitoring equipment, the acoustics specialist will be provided with the hammer model and size, hammer energy settings, and projected blows per minute for the conductor pipe segments requiring hammer pipe-driving. Background in-air and in-water sound levels will be measured at Harmony Platform in the absence of pipe-driving activities to obtain an ambient noise level, and recorded over a frequency range of 10 Hz to 20 kHz. Ambient noise level measurements will be conducted before, during, and after the project. The measured in-air and in-water sound data will be used to recalibrate and refine the sound propagation model used to determine the buffer and exclusion zones. Also, sound pressure levels associated with ramp-up techniques will be measured. In-Water Monitoring—Acoustic monitoring will be performed at a minimum of two fixed stations located at 14 to 30 m (45.9 to 98.4 ft) and approximately 325 to 500 m (+/¥33 m 10%, 1,066.3 to 1,640.4 ft) depending on the conductor pipe sound source location to the monitoring location. E:\FR\FM\30SEN3.SGM 30SEN3 tkelley on DSK3SPTVN1PROD with NOTICES3 Federal Register / Vol. 79, No. 189 / Tuesday, September 30, 2014 / Notices These distances represent the 180 dB and 160 dB (rms) modeled sound levels. The following general approach will be used to measure in-water sound levels: • Acoustic monitoring will be conducted over the entire conductor pipe installation period for each conductor pipe, starting approximately 1 hour prior to conductor pipe installation through 1 hour after impact hammering has stopped. Pre- and posthammer conductor pipe installation data will be used to determine ambient/ background noise levels. • A stationary hydrophone system with the ability to measure and record sound pressure levels will be deployed at a minimum of two monitoring locations (stations). SPLs will be recorded in voltage, converted to microPascals (mPa), and post-processed to decibels (dB [re 1 mPa]). For the first conductor pipe installation, hydrophones are placed at 14 to 30 m (+/¥1 m) and at 325 to 500 (+/¥33 m) depending on the conductor pipe sound source location to the monitoring location at depths ranging from 10 to 30 m (32.8 to 98.4 ft) below the water surface to avoid potential inferences for surface water energy, and to target the depth range of maximum occurrence of marine mammals most likely in the area during the operations. The equipment will obtain data for the most likely depth range of marine mammal occurrence. Horizontal displacement of +/¥10% may be expected for instrument movement due to the water depth and forces from tides, currents, and storms. Additional hydrophone mooring systems may be deployed at additional distances and/or depths. Following each successive conductor pipe installation, the water depth and geographical orientation of the hydrophone may be changed to validate modeled SPLs at varying water depths and direction. • At a minimum, the following sound data will be analyzed (post-processed) from recorded sound levels: Absolute peak overpressure and under pressure levels for each conductor pipe; average, minimum, and maximum sound pressure levels (rms), integrated from 3 Hz to 20 kHz; average duration of each hammer strike (blow), and total number of strikes per continuous impact hammer conductor pipe installation period for each conductor. In the event that field measurements indicate different sound pressure levels (rms) values than those predicted by modeling for either the maximum distances of the buffer or exclusion zones from the conductor sound source, corresponding boundaries for the buffer and appropriate exclusion zones will be VerDate Sep<11>2014 19:40 Sep 29, 2014 Jkt 232001 increased/decreased accordingly, following NMFS notification, concurrence, and authorization. In-Air Monitoring—Reference measurements will be made at approximately 10 to 20 m (32.8 to 65.6 ft) from the initial hammer strike position using a stationary microphone. The microphone will be placed as far away from other large sound sources as practical. The in-air buffer zone predicted for pinnipeds (non-harbor seal, 100 dB re 20 mPa) was estimated at 41 m (134.5 ft) from the hammer impact point on the conductor pipe. Inair sound levels will be recorded at several points around the base of the Harmony Platform at sea level to validate modeled sound levels. Distances closer to the sound source may be monitored for model validation purposes, but only if safety issues are not introduced. Recorded data will be recorded as dB (re 20 mPa, A-weighted and unweighted) for comparison to inair noise thresholds for Level B harassment for pinnipeds. Sound Source Verification—At the initiation of conductor pipe installation activities using the impact hammer (i.e., the installation of the first pipe), direct measurements will be taken in the near and far field of the received levels of underwater and in-air sound versus distance and direction from the sound source using calibrated hydrophones. The acoustic data from the sound source verification will be analyzed as quickly as reasonably practicable in the field and used to verify and adjust (based on the predicted distances) the buffer and exclusion zones distances. The field report will be made available to NMFS for review and approval and PSOs after completing the measurements and before beginning the installation of the remaining conductor pipes. Platform-Based Visual Monitoring ExxonMobil’s PSOs will be based aboard the Harmony Platform and will watch for marine mammals near the platform during conductor pipe installation activities during daytime and nighttime pipe-driving activities. Visual monitoring for marine mammals will be performed at a minimum during periods of active hammer pipe-driving throughout the planned project following general procedures in Baker et al. (2013). Monitoring by PSOs will begin at least 30 minutes before the start of impact hammer pipe-driving, continue through an estimated 2.5 to 3.3 hours of pipe-driving, and conclude 30 minutes after pipe-driving stops (up to 4.3 hours of monitoring per a period of pipe-driving). Five to 7 periods of impact hammer pipe-driving will be PO 00000 Frm 00025 Fmt 4701 Sfmt 4703 58937 required for each conductor pipe. When feasible, PSOs will conduct observations during periods when the impact hammer pipe-driving is not operating for comparison of sighting rates and behavior with and without operations and between pipe-driving periods. In addition to monitoring during pipedriving activities, baseline monitoring of marine mammals will be performed up to one week before and one week after conductor pipe installation, as well as selected periods in between impact hammer pipe-driving activities. The exclusion zone will be monitored to prevent injury to marine mammal species. Based on PSO observations, the impact hammer pipe-driving will be shut-down when marine mammals are observed within or about to enter the designated exclusion zone. The exclusion zone is a region in which a possibility exists of adverse effects on animal hearing or physical effects. A comprehensive monitoring plan will be developed to ensure compliance with the IHA for this project. Methods—There will be a team of 3 PSOs based aboard Harmony Platform conducting monitoring during active hammer pipe-driving periods. Visual observations will take place during active hammering periods which includes both daylight and nighttime operations. This monitoring will occur for approximately 4.3 hours (3.3 hour monitoring plus 0.5 hour pre- and posthammering) during a single hammering phase followed by approximately 6.3 hours of off-duty rest. A total of 5 to 7 observation periods corresponding to the driving of the pipe segments will be anticipated for each of the six conductors. It is possible that an impact hammer pipe-driving session will take less than 3.3 hours and that the ‘‘rest interval’’ for the visual monitors separating driving segments will be less than 6.3 hours. If driving and rest intervals are reduced and additional segments are added (e.g., seven instead of five), two alternating teams of three PSOs may be required. At the conclusion of impact hammer pipedriving activities for a single conductor pipe, PSOs may be transferred to shore to await the next active pipe-driving phase. PSOs will be placed at the best practicable vantage point(s) (e.g., lower platform level, upper platform level) to monitor the applicable buffer and exclusion zones for marine mammals. The PSOs will have authority to implement shut-down/delay ramp-up procedures, if applicable, by calling the hammer operator for a shut-down via radio communication. For the buffer zone, two PSOs will be stationed on an E:\FR\FM\30SEN3.SGM 30SEN3 tkelley on DSK3SPTVN1PROD with NOTICES3 58938 Federal Register / Vol. 79, No. 189 / Tuesday, September 30, 2014 / Notices upper platform deck where they have a clear view of the monitoring area. They will be approximately 180 degrees apart and each will monitor approximately one-half of the corresponding buffer zone and beyond with binoculars and other appropriate equipment. For exclusion zone area, one PSO will concurrently monitor the applicable radii for pinnipeds and cetaceans, respectively, from a lower level observation post that provides a clear view of the sea surface around the actively driven conductor pipe. The lower observation area will be illuminated during nighttime observations. Visual aids may be used but will not be required, providing the PSO has a clear view of the sea surface with the naked eye. A non-PSO safety spotter will also be assigned to the lower deck observation area. The safety spotter will be available to deter errant California sea lions using NMFSrecommended methods (see below) (NMFS, 2008). All personnel operating on the Harmony Platform will be required to receive required training and wear appropriate personal protective equipment. Personal protective equipment is specific to the task, location, and environmental conditions (e.g., weather, operations risks). It includes items such as floatation vests, hard hats, steel-toed shoes, gloves, fireresistant clothing, gear, eye protection, and other protective equipment. Details on specific personal protective equipment items required for PSO and acoustic monitoring will be determined via the regular work risk assessment process, and will be presented in the associated monitoring plans for the project. Equipment for monitoring will include hearing protection from where observations are made from high noise areas of the platform, marine radios with headsets, time keeping device (e.g., watch or cell phone), day and night range finding binoculars (7 x 50 or greater), notebooks with standardized recording forms, species identification guides, and a project-specific monitoring plan approved by NMFS (to be submitted separately). PSO Qualifications—Monitoring will be conducted by qualified PSOs defined in Baker et al. (2013) and approved by NMFS. PSOs dedicated to the planned project will have no other activityrelated tasks. PSO Data and Documentation PSOs will record data to estimate the numbers of marine mammals exposed to various received sound levels and to document apparent disturbance reactions or lack thereof. Data will be used to estimate numbers of animals potentially ‘‘taken’’ by harassment (as defined in the MMPA). They will also provide information needed to order a shut-down of the impact hammer when a marine mammal is within or near the exclusion zone. Visual observations will also be made during pipe-driving activities as well as daytime periods from the Harmony Platform when the regular operations will be underway without pipe-driving activities to collect baseline biological data. When a sighting is made, the following information about the sighting will be recorded: 1. Species, group size, age/size/sex categories (if determinable), behavior when first sighted and after initial sighting, heading (if consistent), bearing and distance from platform, sighting cue, apparent reaction to the sound source (e.g., none, avoidance, approach, paralleling, etc., and including responses to ramp-up), speed of travel, and duration of presence. 2. Date, time, location, heading, speed, activity of the conductor pipe installation activities, weather conditions, Beaufort sea state and wind force, visibility, and sun glare. The data listed under (2) will also be recorded at the start and end of each observation watch, and during a watch whenever there is a change in one or more of the variables. All observations, as well as information regarding ramp-ups or shutdowns will be recorded in a standardized format. Results from the platform-based visual observations will provide the following information: 1. The basis for real-time mitigation (impact hammer shut-down). 2. Information needed to estimate the number of marine mammals potentially taken by harassment, which must be reported to NMFS. 3. Data on the occurrence, distribution, and activities of marine mammals in the area where the conductor pipe installation activities are conducted. 4. Information to compare the distance and distribution of marine mammals relative to the source platform at times with and without pipe-driving activities. 5. Data on the behavior and movement patterns of marine mammals seen at times with and without pipedriving activities. Reporting ExxonMobil will submit a comprehensive report to NMFS within 90 days after the end of the conductor VerDate Sep<11>2014 19:40 Sep 29, 2014 Jkt 232001 PO 00000 Frm 00026 Fmt 4701 Sfmt 4703 pipe installation activities and the expiration of the IHA (if issued). The report would describe the pipe-driving activities that were conducted and sightings of marine mammals near the operations. The report submitted to NMFS will provide full documentation of methods, results, and interpretation pertaining to all monitoring. The 90-day report will summarize the dates and location of impact hammer pipe-driving activities and all marine mammal sightings (i.e., dates, times, locations, activities, and associated seismic survey activities). The report will minimally include: • Summaries of monitoring effort— total hours, total distances, and distribution of marine mammals through the activity period accounting for Beaufort sea state and other factors affecting visibility and detectability of marine mammals; • Analyses of the effects of various factors influencing detectability of marine mammals including Beaufort sea state, number of PSOs, and fog/glare; • Species composition, occurrence, and distribution of marine mammals sightings including date, water depth, numbers, age/size/gender, and group sizes; and analyses of the effects of activities; • Sighting rates of marine mammals during periods with and without impact hammer pipe-driving activities (and other variables that could affect detectability); • Initial sighting distances versus operational activity state; • Closest point of approach versus operational activity state; • Observed behaviors and types of movements versus operational activity state; • Numbers of sightings/individuals seen versus operational activity state; and • Distribution around the platform versus operational activity state. The report will also include estimates of the number and nature of exposures that could result in ‘‘takes’’ of marine mammals by harassment or in other ways (based on presence in the buffer and/or exclusion zones). After the report is considered final, it will be publicly available on the NMFS Web site at: https://www.nmfs.noaa.gov/pr/permits/ incidental/. Reporting Prohibited Take—In the unanticipated event that the specified activity clearly causes the take of a marine mammal in a manner prohibited by this IHA, such as an injury (Level A harassment), serious injury, or mortality (e.g., ship-strike, gear interaction, and/or entanglement), ExxonMobil will E:\FR\FM\30SEN3.SGM 30SEN3 Federal Register / Vol. 79, No. 189 / Tuesday, September 30, 2014 / Notices immediately cease the specified activities and immediately report the incident to the Chief of the Permits and Conservation Division, Office of Protected Resources, NMFS at 301–427– 8401 and/or by email to Jolie.Harrison@ noaa.gov and Howard.Goldstein@ noaa.gov and the West Coast Regional Stranding Coordinator (562–980–3230). The report must include the following information: • Time, date, and location (latitude/ longitude) of the incident; • Type of activity involved; • Description of the circumstances during and leading up to the incident; • Status of all sound source use in the 24 hours preceding the incident; • Water depth; • Environmental conditions (e.g., wind speed and direction, Beaufort sea state, cloud cover, and visibility); • Description of all marine mammal observations in the 24 hours preceding the incident; • Species identification or description of the animal(s) involved; • Fate of the animal(s); and • Photographs or video footage of the animal(s) (if equipment is available). Activities shall not resume until NMFS is able to review the circumstances of the prohibited take. NMFS shall work with ExxonMobil to determine what is necessary to minimize the likelihood of further prohibited take and ensure MMPA compliance. ExxonMobil may not resume their activities until notified by NMFS via letter or email, or telephone. Reporting an Injured or Dead Marine Mammal with an Unknown Cause of Death—In the event that ExxonMobil 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 (i.e., in less than a moderate state of decomposition as described in the next paragraph), ExxonMobil will immediately report the incident to the Chief of the Permits and Conservation Division, Office of Protected Resources, NMFS, at 301–427–8401, and/or by email to Jolie.Harrison@noaa.gov and Howard.Goldstein@noaa.gov, and the NMFS West Coast Regional Office (1– 866–767–6114) and/or to the West Coast Regional Stranding Coordinator (562– 980–3230). The report must include the same information identified in the paragraph above. Activities may continue while NMFS reviews the circumstances of the incident. NMFS will work with ExxonMobil to determine whether modifications to the activities are appropriate. Reporting an Injured or Dead Marine Mammal Not Related to the Activities— In the event that ExxonMobil 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 IHA (e.g., previously wounded animal, carcass with moderate or advanced 58939 decomposition, or scavenger damage), ExxonMobil will report the incident to the Chief of the Permits and Conservation Division, Office of Protected Resources, NMFS, at 301– 427–8401, and/or by email to Jolie.Harrison@noaa.gov and Howard.Goldstein@noaa.gov, and the NMFS West coast Regional Office (1– 866–767–6114) and/or to the West Coast Regional Stranding Coordinator (562– 980–3230), within 24 hours of discovery. ExxonMobil will provide photographs or video footage (if available) or other documentation of the stranded animal sighting to NMFS and the Marine Mammal Stranding Network. Activities may continue while NMFS reviews the circumstances of the incident. 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 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]. TABLE 6—NMFS’S CURRENT UNDERWATER AND IN-AIR ACOUSTIC EXPOSURE CRITERIA Criterion Criterion definition Threshold Impulsive (Non-Explosive) Sound Level A harassment (injury) ............................... Permanent threshold shift (PTS) (Any level above that which is known to cause TTS). Level B harassment ........................................... Level B harassment ........................................... Behavioral disruption (for impulsive noise) ...... Behavioral disruption (for continuous noise) ... 180 dB re 1 μPa-m (root means square [rms]) (cetaceans). 190 dB re 1 μPa-m (rms) (pinnipeds). 160 dB re 1 μPa-m (rms). 120 dB re 1 μPa-m (rms). In-Air Sound tkelley on DSK3SPTVN1PROD with NOTICES3 Level A harassment ........................................... Level B harassment ........................................... NA .................................................................... Behavioral disruption ........................................ NA. 90 dB re 20 μPa (harbor seals). 100 dB re 20 μPa (all other pinniped species). NA (cetaceans). Level B harassment is anticipated and authorized as a result of the conductor pipe installation activities at the Harmony Platform in the Santa Barbara Channel offshore of California. Acoustic stimuli (i.e., increased underwater and in-air sound) generated during the pipedriving activities are expected to result in the behavioral disturbance of some marine mammals. There is no evidence that the planned activities could result in injury, serious injury, or mortality for which ExxonMobil seeks the IHA. The required mitigation and monitoring measures will minimize any potential risk for injury, serious injury, or mortality. VerDate Sep<11>2014 19:40 Sep 29, 2014 Jkt 232001 PO 00000 Frm 00027 Fmt 4701 Sfmt 4703 E:\FR\FM\30SEN3.SGM 30SEN3 58940 Federal Register / Vol. 79, No. 189 / Tuesday, September 30, 2014 / Notices The following sections describe ExxonMobil and NMFS’s methods to estimate take by incidental harassment and present the total take authorized incidental to the conductor pipe installation activities at the Harmony Platform in the Santa Barbara Channel offshore of California. The estimated takes were calculated using information on sound source levels, sound propagation, maximum distances from the sound source to Level A and Level B harassment exposure thresholds, and estimated density of marine mammals in the action area. Take estimates were calculated for in-water (cetaceans and pinnipeds) and in-air (pinnipeds only). The estimates are based on the following information: • Thresholds for marine mammals to in-water and in-air noise; • Sound levels at the conductor pipe from hammer strike; • Sound propagation (transmission/ spreading loss) through the environment (i.e., air, water); • Maximum distances from the sound sources to the corresponding impact zones (based on Level A and Level B harassment thresholds) for marine mammals; • Density estimate for each species of marine mammals (calculated as stock abundance divided by 12,592 km2 [3,671.2 nmi2]area [except where noted]); and • Number of takes for each species of marine mammals within a group (calculated as density multiplied by buffer/exclusion zone multiplied by days of activity). Sound levels for impulsive (impact) pipe-driving by the hammer and propagation through water and in-air at the Harmony Platform were modeled by JASCO Applied Sciences, Ltd. The modeling results are presented in JASCO’s acoustic modeling report as an addendum to the IHA application titled ‘‘Assessment of Airborne and Underwater Noise from Pile Driving Activities at the Harmony Platform.’’ Methods used to estimate marine mammal densities and takes for the action area in the Santa Barbara Channel are presented in Sections 6.1.5 and 6.1.6 of the IHA application for likely exposures to species of marine mammals. Densities of marine mammal species likely to occur in the action area of the Santa Barbara Channel were taken directly from scientific literature or calculated using corresponding abundances in NMFS Stock Assessment Reports. Density estimates for sperm and Baird’s beaked whale, and shortbeaked common, Pacific white-sided, Risso’s, and northern right whale dolphin, and Dall’s porpoise were determined using the Strategic Environmental and Development Program (SERDP)/National Aeronautics and Space Administration (NASA)/ NOAA Marine Animal Mapper and OBIS–SEAMAP database using NMFS Southwest Fisheries Science Center (SWFSC) summer densities for the California Current ecosystem. Density estimates for the blue, fin, and humpback whale were taken directly from Redfern et al. (2013), using the upper limit reported for the density contour that includes the Harmony Platform. Redfern et al. (2013) estimated densities for these three species using NMFS sightings collected from primarily August through November over a period from 1991 to 2009 throughout the Santa Barbara Channel. Results for blue, fin, and humpback whales are presented in Figures 6–3, 6– 4, and 6–5 of the IHA application. These densities are considered more accurate than those based on reported stock abundances because even though they are for the same monthly period and geographical location, they include a correction factor to correct for nonobservational periods. For calculated densities of likely affected marine mammal species, stock abundances, which generally range from the state of Washington to northern Baja California, Mexico, were assumed to be concentrated within the 12,593 km2 (3,671.5 nmi2) action area in the Santa Barbara Channel. The action area includes the Harmony Platform, and extends 18 km (9.7 nmi) to the north, 60 km (32.4 nmi) to the west, and 70 km (37.8 nmi) to the south of Point Conception, California. The eastern boundary is 35 km (18.9 nmi) east of Anacapa Island. Use of this area produces a conservative density estimate because the geographical range of each marine mammal species evaluated is much greater than 70 km (nmi) of the coastline selected to represent the action area, including season-specific ranges for species that migrate (e.g., gray whale). For marine mammal species potentially exposed to in-air noise, pinniped densities were calculated by dividing the stock abundance for each marine mammal species by the 1,130 m2 (12,163.2 ft2) impact area of the Harmony Platform near sea level where the animals could potentially haul-out and/or have their heads out of the water. Tables 6–7 and 6–8 of the IHA application describe the calculated densities and estimated take by marine mammal species as well as associated data for the in-water and inair sound thresholds, respectively. Although there is some uncertainty about the representativeness of the data and the assumptions used in the calculations below, the approach used here is believed to be the best available approach. TABLE 7—ESTIMATED DENSITIES AND POSSIBLE NUMBER OF MARINE MAMMAL SPECIES THAT MIGHT BE EXPOSED TO GREATER THAN OR EQUAL TO 160 dB (PIPE-DRIVING ACTIVITIES) DURING EXXONMOBIL’S CONDUCTOR PIPE INSTALLATION ACTIVITIES IN THE SANTA BARBARA CHANNEL OFFSHORE OF CALIFORNIA Density in action area (#/km2)1 tkelley on DSK3SPTVN1PROD with NOTICES3 Species Calculated take from pipe-driving activities in-water (i.e., estimated number of individuals exposed to sound levels ≥160 dB re 1 μPa) 4 Calculated take from pipe-driving activities in-air (i.e., estimated number of individuals exposed to sound levels ≥90 dB re 20 μPa for harbor seals and 90 dB re 20 μPa for all other pinnipeds) 5 Total authorized Take 6 Approximate percentage of population/ stock estimate (for authorized take) 8 Abundance 7 Population trend 7 Mysticetes North Pacific right whale. VerDate Sep<11>2014 19:40 Sep 29, 2014 NA Jkt 232001 0 PO 00000 0 Frm 00028 Fmt 4701 0 Sfmt 4703 NA (26)—Eastern North Pacific stock. E:\FR\FM\30SEN3.SGM 30SEN3 NA NA. 58941 Federal Register / Vol. 79, No. 189 / Tuesday, September 30, 2014 / Notices TABLE 7—ESTIMATED DENSITIES AND POSSIBLE NUMBER OF MARINE MAMMAL SPECIES THAT MIGHT BE EXPOSED TO GREATER THAN OR EQUAL TO 160 dB (PIPE-DRIVING ACTIVITIES) DURING EXXONMOBIL’S CONDUCTOR PIPE INSTALLATION ACTIVITIES IN THE SANTA BARBARA CHANNEL OFFSHORE OF CALIFORNIA—Continued Density in action area (#/km2)1 Calculated take from pipe-driving activities in-water (i.e., estimated number of individuals exposed to sound levels ≥160 dB re 1 μPa) 4 Calculated take from pipe-driving activities in-air (i.e., estimated number of individuals exposed to sound levels ≥90 dB re 20 μPa for harbor seals and 90 dB re 20 μPa for all other pinnipeds) 5 1.5188 3.063 0 10 Humpback whale ......... 3 0.0055 0.0332 0 2 Minke whale ................. 0.04 0.2418 0 2 Bryde’s whale ............... Sei whale ..................... NA 0.01 0 0.0605 0 0 2 2 Fin whale ...................... 3 0.0065 0.0392 0 2 Blue whale ................... 2 0.006 0.00362 0 2 Sperm whale ................ 2 0.0000542 0.000327 0 2 Pygmy sperm whale .... 0.05 0.302 0 1 Dwarf sperm whale ...... Baird’s beaked whale ... NA 2 0.001224 0 0.0074 0 0 0 6 Cuvier’s beaked whale 0.5233 3.1633 0 4 Mesoplodon beaked whale. Killer whale ................... 0.0551 0.3331 0 2 0.07464 0.4512 0 10 False killer whale ......... Short-finned pilot whale NA 0.06 0 0.3627 0 0 50 40 Bottlenose dolphin ....... 0.0799 0.4829 0 10 Striped dolphin ............. 2 0.002711 0.0164 0 20 Short-beaked common dolphin. Long-beaked common dolphin. Pacific white-sided dolphin. Northern right whale dolphin. Risso’s dolphin ............. 2 0.946007 5.7186 0 450 8.5 51.3825 0 120 2 0.068630 0.4149 0 30 2 0043996 0.2659 0 100 2 0.053323 0.3223 0 10 Dall’s porpoise ............. 0.028931 0.1749 0 50 Harbor porpoise ........... 0 0 0 0 Species Eastern North Pacific Gray whale. Total authorized Take 6 Approximate percentage of population/ stock estimate (for authorized take) 8 Abundance 7 19,126 (18,107)—Eastern North Pacific stock 155 (142)— Western North Pacific population. 1,918 (1,855)—CA/OR/ WA stock. 478 (202)—CA/OR/WA stock. NA ................................ 126 (83)—Eastern North Pacific stock. 3,051 (2,598)—CA/OR/ WA stock. 1,647 (1,551)—Eastern North Pacific stock. 0.05 0.1 Population trend 7 Increasing over past several decades— Eastern North Pacific stock. Increasing. 0.42 NA. NA 1.58 NA. NA. 0.07 Increasing. 0.12 NA. 0.21 NA. 0.17 NA. NA 0.71 NA. NA. 0.06 Declining off CA/OR/ WA. Declining off CA/OR/ WA. NA—Eastern North Pacific Offshore stock; NA—Eastern North Pacific Transient stock; Increasing— West Coast Transient stock. NA. NA. tkelley on DSK3SPTVN1PROD with NOTICES3 Odontocetes 971 (751)—CA/OR/WA stock. 579 (271)—CA/OR/WA stock. NA—CA/OR/WA stock 847 (466)—CA/OR/WA stock. 6,590 (4,481)—CA/OR/ WA stock. 694 (389)—CA/OR/WA stock. 240 (162)—Eastern North Pacific stock 346 (346)—Eastern North Pacific Transient stock 354 (354)—West Coast Transient stock. NA ................................ 760 (465)—CA/OR/WA stock. 1,006 (684)—CA/OR/ WA stock. 0.29 4.17/2.89/2.82 10,908 (8,231)—CA/ OR/WA stock. 411,211 (343,990)— CA/OR/WA stock. 107,016 (76,224)—CA stock. 26,930 (21,406)—CA/ OR/WA stock. 8,334 (6,019)—CA/OR/ WA stock. 6,272 (4,913)—CA/OR/ WA stock. 42,000 (32,106)—CA/ OR/WA stock. NA ................................ NA 5.26 0.99 0.18 0.11 NA—CA/OR/WA Offshore stock; NA—CA Coastal stock. NA. 0.11 Varies with oceanographic conditions. Increasing over last 30 years. NA. 1.19 NA. 0.16 NA. 0.12 NA. NA NA. 0.11 Pinnipeds California sea lion ........ 23.6 142.662 17.997 Steller sea lion ............. NA 0 0 143 + 18 = 161 0 Pacific harbor seal ....... 2.4 14.508 5.491 15 + 6 = 21 Fmt 4701 Sfmt 4703 VerDate Sep<11>2014 19:40 Sep 29, 2014 Jkt 232001 PO 00000 Frm 00029 296,750 (153,337)— U.S. stock. 49,685 (42,366)—Western stock 58,334 (72,223)—Eastern stock. 30,196 (26,667)—CA stock. E:\FR\FM\30SEN3.SGM 30SEN3 0.05 NA 0.07 Increasing. Declining—Western stock; Increasing— Eastern stock; Declining in CA. Increased 1981 to 2004. 58942 Federal Register / Vol. 79, No. 189 / Tuesday, September 30, 2014 / Notices TABLE 7—ESTIMATED DENSITIES AND POSSIBLE NUMBER OF MARINE MAMMAL SPECIES THAT MIGHT BE EXPOSED TO GREATER THAN OR EQUAL TO 160 dB (PIPE-DRIVING ACTIVITIES) DURING EXXONMOBIL’S CONDUCTOR PIPE INSTALLATION ACTIVITIES IN THE SANTA BARBARA CHANNEL OFFSHORE OF CALIFORNIA—Continued Density in action area (#/km2)1 Calculated take from pipe-driving activities in-water (i.e., estimated number of individuals exposed to sound levels ≥160 dB re 1 μPa) 4 Calculated take from pipe-driving activities in-air (i.e., estimated number of individuals exposed to sound levels ≥90 dB re 20 μPa for harbor seals and 90 dB re 20 μPa for all other pinnipeds) 5 Northern elephant seal 9.85 59.5433 7.512 60 + 8 = 68 Northern fur seal .......... 0.79 4.7756 0.602 5+1=6 Guadalupe fur seal ...... NA 0 0 0 Species Total authorized Take 6 Abundance 7 Approximate percentage of population/ stock estimate (for authorized take) 8 124,000 (74,913)—CA breeding stock. 12,844 (6,722)—California stock. 7,408 (3,028)—Mexico to CA stock. 0.05 0.05 NA Population trend 7 Increasing through 2005. Increasing. Increasing. tkelley on DSK3SPTVN1PROD with NOTICES3 NA = Not available or not assessed. 1 Planned action area (12,593 km2) in the Santa Barbara Channel off the coast of California. 2 OBIS–SEAMAP SERDP–SDSS NMFS SWFSC summer density data for the California Current ecosystem. 3 Redfern et al. (2013) 4 Calculated take is the estimated number of animals in the in-water ensonified buffer zone multiplied by the number of days (18.6). 5 Calculated take is the estimated number of animals in the in-air ensonified buffer zone multiplied by the number of days (18.6). 6 Authorized take includes calculated takes for animals in the ensonified in-water and in-air buffer zones. Authorized takes for cetaceans were increased to account for group size. 7 NMFS Marine Mammal Stock Assessment Reports (Caretta et al., 2013) 8 Total authorized (and calculated) takes expressed as percentages of the species or stock. Numbers of marine mammals that might be present and potentially disturbed are estimated based on the available data about marine mammal distribution and densities in the Santa Barbara Channel action area. ExxonMobil estimated the number of different individuals of marine mammal species that may be exposed to in-water and in-air sounds with received levels greater than or equal to 160 dB re 1 mPa (rms) and in-air sounds with received levels greater than or equal to 90 dB re 20 mPa (rms) (for harbor seals)/100 dB re 20 mPa (rms) (for all other pinniped species) for impact hammer pipedriving activities on one or more occasions by considering the total marine area that will be within the 160 dB in-water radius and 90 dB (for harbor seals)/100 dB (for all other pinniped species) in-air radius around the impact hammer pipe-driving on at least one occasion and the expected density of marine mammals in the area (in the absence of the conductor pipe installation activities). The number of possible exposures can be estimated by considering the total marine area that will be within the in-water 160 dB radius and in-air 90 dB (for harbor seals)/100 dB (for all other pinniped species) radius around the impact hammer pipe-driving activities. The inwater 160 dB and in-air 90dB (harbor seal)/100 dB (for all other pinniped species) radii are based on acoustic modeling data for the impact hammer pipe-driving activities that may be used during the action (see the addendum to the IHA application). It is unlikely that VerDate Sep<11>2014 19:40 Sep 29, 2014 Jkt 232001 a particular animal will stay in the area during the entire impact hammer pipedriving activities. The number of different individuals potentially exposed to received levels greater than or equal to 160 dB re 1 mPa (rms) for in-water noise and 90 dB re 20 mPa (rms) (for harbor seals)/100 dB re 20 mPa (rms) (for all other pinniped species) for in-air noise from impact hammer pipe-driving activities was calculated by multiplying: (1) The expected species density (in number/km2), times (2) The anticipated area to be ensonified to that level during conductor pipe installation (buffer zone = p x [maximum distance]2), times (3) The number of days of the conductor pipe installation activities. NMFS notes that ExxonMobil had estimated the total number of days of the conductor pipe installation activities as 4.125 in its application, based on the total number of estimated hours of impact pipe-driving. NMFS received comments during the public comment period stating that this approach underestimates the number of days of actual exposure to the installation activities because pipe-driving sessions will be interspersed between periods of no pipe-driving. Specifically, the Commission commented that ExxonMobil should have added 3.3 hours of estimated pile-driving per section to 7.3 hours of downtime per section for a total of 10.6 hours per section of pipe. Multiplying that by the projected seven sections to be driven for each conductor pipe would result in a PO 00000 Frm 00030 Fmt 4701 Sfmt 4703 total of 74.2 hours, which when divided by 24 hours per day equates to 3.1 days of potential exposure per pipe. Using this method would yield a total of 18.6 days of potential exposure (3.1 days per conductor pipe multiplied by 6 pipes), which more accurately represents the total duration of proposed conductor pipe installation activities for all six conductor pipes. NMFS agrees, and revised the total number of days of installation activities to 18.6. Applying the approach described above, approximately 0.3318 km2 will be ensonified within the in-water 160 dB isopleth and approximately 0.0053 km2/0.0475 km2 will be ensonified within the in-air 90 dB (harbor seals)/ 100 dB (for all other pinniped species) isopleths for impact hammer pipedriving activities (assuming omnidirectional spreading of sound from the conductor pipe) during the conductor pipe installation activities. The take calculations within the action area account for animals in the initial density snapshot and account for new (i.e., turnover) or previously exposed animals over an approximate 18.6 day period that approach and enter the area ensonified above or equal to the 160 dB isopleth for in-water noise and 90/100 dB isopleth for in-air noise from the impact hammer pipe-driving activities; however, studies suggest that many marine mammals will avoid exposing themselves to sounds at these levels, which suggests that there will not necessarily be a large number of new animals entering the action area once the conductor pipe installation activities E:\FR\FM\30SEN3.SGM 30SEN3 Federal Register / Vol. 79, No. 189 / Tuesday, September 30, 2014 / Notices tkelley on DSK3SPTVN1PROD with NOTICES3 started. Also, the approach assumes that no cetaceans or pinnipeds will move away or toward the Harmony Platform. The take estimates represent the number of individuals that are expected (in absence of conductor pipe installation activities) to occur over an approximate 18.6 day period of time in the waters that will be exposed to greater than or equal to 160 dB (rms) in-water and greater than or equal to 90/100 dB (rms) in-air for impact hammer pipe-driving activities. ExxonMobil’s estimates of exposures to various sound levels assume that the planned activities will be carried out in full. The estimates of the numbers of marine mammals potentially exposed to 160 dB (rms) for in-water noise and 90 dB re 20 mPa (rms) (for harbor seals)/100 dB re 20 mPa (rms) (for all other pinniped species) for in-air noise received levels are precautionary and probably overestimate the actual numbers of marine mammals that could be involved. These estimates include standard contingencies for weather, equipment, or mitigation delays in the time planned for the planned activities. The authorized takes were increased for certain marine mammal species (i.e., gray, humpback, minke, sei, fin, blue, sperm, Baird’s beaked, Cuvier’s beaked, Mesoplodont beaked, killer, and shortfinned pilot whales and bottlenose, striped, short-beaked common, longbeaked common, Pacific white-sided, northern right whale, and Risso’s dolphins and Dall’s porpoise) to account for group behavior. Based on recommendations from the CCC received during the 30-day public comment period on the notice of the proposed IHA (79 FR 36743, June 30, 2014), NMFS has authorized takes for Bryde’s whales and false killer whales, which are considered warmer water species. Table 7 shows the estimates of the number of different individual marine mammals anticipated to be exposed to greater than or equal to 160 dB re 1 mPa (rms) for the conductor pipe installation activities if no animals moved away from the Harmony Platform. No takes by Level A harassment have been authorized. The total take authorization is given in the fifth column of Table 7. Encouraging and Coordinating Research ExxonMobil will coordinate the planned marine mammal monitoring program associated with the conductor pipe installation activities with researchers and other parties that express interest in this activity, area, and anthropogenic sound effects on marine mammals. ExxonMobil will VerDate Sep<11>2014 19:40 Sep 29, 2014 Jkt 232001 coordinate with applicable U.S. agencies (e.g., NMFS), and will comply with their requirements. ExxonMobil supports research on marine mammals and sound in the environment through academic, industry, and private sector collaborations. ExxonMobil is a founding member and largest contributor to the Sound and Marine Life Joint Industry Program (JIP) through the International Oil and Gas Producers (OGP), and the International Association of Geophysical Contractors (IAGC). Through JIP and other venues, ExxonMobil provides annual funding and support for fundamental and applied scientific research to better understand the effects of anthropogenic sound on marine life. ExxonMobil also conducts internal research and monitoring programs specific to sound effects from exploration and production activities. These efforts have helped produce effective mitigation strategies and techniques to reduce potential sound effects on marine mammals from their operations and those from the oil and gas industry as a whole. More information on selected examples of ExxonMobil’s involvement and contributions to scientific research on marine mammals and sound can be found in section 14 of the IHA application. Impact on Availability of Affected Species or Stock for Taking for Subsistence Uses Section 101(a)(5)(D) of the MMPA also requires NMFS to determine that the authorization will not have an unmitigable adverse effect on the availability of marine mammal species or stocks for subsistence use. There are no relevant subsistence uses of marine mammals implicated by this action. Therefore, NMFS has determined that the total taking of affected species or stocks will not have an unmitigable adverse impact on the availability of such species or stocks for taking for subsistence purposes. Analysis and Determinations Negligible Impact Negligible impact is ‘‘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’’ (50 CFR 216.103). A negligible impact finding is based on the lack of likely adverse effects on annual rates of recruitment or survival (i.e., populationlevel effects). An estimate of the number of Level B harassment takes, alone, is PO 00000 Frm 00031 Fmt 4701 Sfmt 4703 58943 not enough information on which to base an impact determination. In addition to considering estimates of the number of marine mammals that might be ‘‘taken’’ through behavioral harassment, NMFS must consider other factors such as the likely nature of any responses (their intensity, duration, etc.), the context of any responses (critical reproductive time or location, migration, etc.), as well as the number and nature of estimated Level A harassment takes, the number of estimated mortalities, and effects on habitat. In making a negligible impact determination, NMFS evaluated factors such as: (1) The number of anticipated injuries, serious injuries, or mortalities; (2) The number, nature, and intensity, and duration of Level B harassment (all relatively limited); and (3) The context in which the takes occur (i.e., impacts to areas of significance, impacts to local populations, and cumulative impacts when taking into account successive/ contemporaneous actions when added to baseline data); (4) The status of stock or species of marine mammals (i.e., depleted, not depleted, decreasing, increasing, stable, impact relative to the size of the population); (5) Impacts on habitat affecting rates of recruitment/survival; and (6) The effectiveness of monitoring and mitigation measures. As described above and based on the following factors, the specified activities associated with the conductor pipe installation activities are not likely to cause PTS, or other non-auditory injury, serious injury, or death. The factors include: (1) The likelihood that marine mammals are expected to move away from a noise source that is annoying prior to its becoming potentially injurious; (2) The potential for temporary or permanent hearing impairment is relatively low and will likely be avoided through the implementation of the required monitoring and mitigation (i.e., shut-down) measures; (3) The fact that cetaceans and pinnipeds will have to be closer than 10 m and 3.5 m, respectively, during impact hammer pipe-driving activities to be exposed to levels of underwater sound believed to have a minimal chance of causing a permanent threshold shift (PTS; i.e., Level A harassment); and (4) The likelihood that marine mammal detection ability by trained E:\FR\FM\30SEN3.SGM 30SEN3 tkelley on DSK3SPTVN1PROD with NOTICES3 58944 Federal Register / Vol. 79, No. 189 / Tuesday, September 30, 2014 / Notices PSOs is high at close proximity to the platform. No injuries, serious injuries, or mortalities are anticipated to occur as a result of ExxonMobil’s planned conductor pipe installation activities, and none are authorized by NMFS. Table 7 of this document outlines the number of authorized Level B harassment takes that are anticipated as a result of these activities. NMFS’s practice has been to apply the 160 dB re 1 mPa (rms) received level threshold for underwater impulse sound levels to determine whether take by Level B harassment occurs. Southall et al. (2007) provide a severity scale for ranking observed behavioral responses of both free-ranging marine mammals and laboratory subjects to various types of anthropogenic sound (see Table 4 in Southall et al. [2007]). Current NMFS practice, regarding exposure of marine mammals to high-level in-air sounds, as a threshold for potential Level B harassment, is at or above 90 dB re 20 mPa for habor seals and at or above 100 dB re 20 mPa for all other pinniped species (Lawson et al., 2002; Southall et al., 2007). NMFS has not determined Level A harassment thresholds for marine mammals for in-air noise. As mentioned previously, NMFS estimates that 32 species of marine mammals under its jurisdiction could be potentially affected by Level B harassment over the course of the IHA. The population estimates for the marine mammal species that may be taken by Level B harassment were provided in Table 4 and 7 of this document. Due to the nature, degree, and context of Level B (behavioral) harassment anticipated and described (see ‘‘Potential Effects on Marine Mammals’’ section above) in this notice, the planned activity is not expected to impact rates of annual recruitment or survival for any affected species or stock, particularly given NMFS’s and the applicant’s requirement to implement mitigation, monitoring, and reporting measures to minimize impacts to marine mammals. Additionally, the conductor pipe installation activities will not adversely impact marine mammal habitat. For the marine mammal species that may occur within the action area, there are no known designated or important feeding and/or reproductive areas. Many animals perform vital functions, such as feeding, resting, traveling, and socializing, on a diel cycle (i.e., 24 hr cycle). Behavioral reactions to noise 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 VerDate Sep<11>2014 19:40 Sep 29, 2014 Jkt 232001 subsequent days (Southall et al., 2007). Potential impacts are not likely to be significant from the pipe-driving activities as the use of the impact hammer will occur over 30 intermittent intervals of 2.5 to 3.3 hours each interspersed with period of downtime, for a cumulative total of about 18.6 days of potential exposure spread out over a 91-day period. Additionally, the conductor pipe installation activities will be increasing sound levels in the marine environment in a relatively small area surrounding the Harmony Platform (compared to the range of the animals), and some animals may only be exposed to and harassed by sound for less than a day. Of the 37 marine mammal species under NMFS jurisdiction that may or are known to likely to occur in the action area, seven are listed as threatened or endangered under the ESA: North Pacific right, western North Pacific gray whale, humpback, sei, fin, blue, and sperm whale and Guadalupe fur seal. These species are also considered depleted under the MMPA. Of these ESA-listed species, incidental take has been requested to be authorized for humpback, sei, fin, blue, and sperm whales. There is generally insufficient data to determine population trends for the other depleted species in the action area. To protect these animals (and other marine mammals in the action area), ExxonMobil must cease impact hammer pipe-driving activities if any marine mammal enters designated exclusion zones. No injury, serious injury, or mortality is expected to occur and due to the nature, degree, and context of the Level B harassment anticipated, and the activities are not expected to impact rates of recruitment or survival. NMFS has determined, provided that the aforementioned mitigation and monitoring measures are implemented, the impact of conducting pipe-driving activities in the Santa Barbara Channel off the coast of California, may result, at worst, in a modification in behavior and/or low-level physiological effects (Level B harassment) of certain species of marine mammals. Changes in diving/surfacing patterns, habitat abandonment due to loss of desirable acoustic environment, and cessation of feeding or social interaction are some of the significant behavioral modifications that could potentially occur as a result of the conductor pipe installation activities. While behavioral modifications, including temporarily vacating the area during the impact hammer pipe-driving activities, may be made by these marine mammal species to avoid the resultant acoustic PO 00000 Frm 00032 Fmt 4701 Sfmt 4703 disturbance, the availability of alternate areas within these areas for species and the short and sporadic duration of the conductor pipe installation activities have led NMFS to determine that the taking by Level B harassment from the specified activity will have a negligible impact on the affected species in the specified geographic region. NMFS believes that the length of the conductor pipe installation activities (approximately 18.6 days total), the requirement to implement mitigation measures (e.g., shut-down of impact hammer pipe-driving activities), and the inclusion of the monitoring and reporting measures, will reduce the amount and severity of the potential impacts from the activity to the degree that it will have a negligible impact on the species or stocks in the action area. 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 required monitoring and mitigation measures, NMFS finds that the total marine mammal take from ExxonMobil’s conductor pipe installation activities will have a negligible impact on the affected marine mammal species or stocks. Small Numbers The estimate of the number of individual cetaceans and pinnipeds that could be exposed to pipe-driving sounds with received levels greater than or equal to 160 dB re 1 mPa (rms) for all marine mammals for in-water sound levels and at or above 90 dB re 20 mPa for harbor seals and at or above 100 dB re 20 mPa for all other pinniped species for in-air sound levels during the conductor pipe installation activities is in Table 7 of this document. In total, 10 gray, 2 humpback, 2 minke, 2 Bryde’s, 2 sei, 2 fin, 2 blue, and 2 sperm whale could be taken by Level B harassment during the conductor pipe installation activities, which will represent 0.05, 0.05, 0.2, unknown, 0.8, 0.03, 0.06, and 0.21% of the stock populations, respectively. Some of the cetaceans potentially taken by Level B harassment are delphinids and porpoises with estimates of 1 pygmy sperm, 6 Baird’s beaked, 4 Cuvier’s beaked, 2 Mesoplodon spp. beaked, 10 killer, 50 false killer, and 40 short-finned pilot whale, 10 bottlenose, 20 striped, 450 short-beaked common, 120 long-beaked common, 20 Pacific white-sided, 100 northern right whale, and 10 Risso’s dolphin as well as 50 Dall’s porpoise, which will represent 0.17, 0.71, 0.06, 0.29, 4.17/2.89/2.82, unknown, 5.26, 0.99, 0.18, 0.11, 0.11, E:\FR\FM\30SEN3.SGM 30SEN3 tkelley on DSK3SPTVN1PROD with NOTICES3 Federal Register / Vol. 79, No. 189 / Tuesday, September 30, 2014 / Notices 0.11, 1.19, 0.16, and 0.12% of the affected stock populations, respectively. The pinnipeds that could potentially be taken by Level B harassment are the California sea lion, Pacific harbor and northern elephant seal, and northern fur seal with estimates of 161, 21, 68, and 6 individuals, which will represent 0.05, 0.07, 0.05, and 0.05% of the affected stock populations, respectively. NMFS has determined that the authorized take estimates represent small numbers relative to the affected species or stocks sizes (i.e., all are less than 6%). 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 finds that small numbers of marine mammals will be taken relative to the populations of the affected species or stocks. See Table 7 for the authorized take numbers of marine mammals. No known current regional population or stock abundance estimates for the northeast Pacific Ocean offshore of California are available for the two species under NMFS’s jurisdiction that could potentially be affected by Level B harassment over the course of the IHA. These species include the Bryde’s whale and false killer whale. Bryde’s whales are distributed worldwide in tropical and sub-tropical waters and their occurrence in the action area is rare. Surveys have shown them to be common and distributed throughout the eastern tropical Pacific Ocean with a concentration around the equator east of 110° West and a reduction west of 140° West. Bryde’s whales in California are likely to belong to a larger population inhabiting at least the eastern part of the tropical Pacific Ocean. In the western North Pacific Ocean, Bryde’s whale abundance in the early 1980s was estimated to be 22,000 to 24,000 (Tillman and Mizroch, 1982; Miyashita, 1986). Bryde’s whale abundance has never been estimated for the entire eastern Pacific Ocean; however, a portion of that stock in the eastern tropical Pacific Ocean was estimated as 13,000 (Wade and Gerrodette, 1993). The false killer whale is distributed worldwide throughout warm temperate and tropical oceans and their occurrence in the action area is rare. In VerDate Sep<11>2014 19:40 Sep 29, 2014 Jkt 232001 the North Pacific Ocean, this species is well known from southern Japan, Hawaii, and the eastern tropical Pacific Ocean. This species occurs in the U.S. waters of the northern Gulf of Mexico, Hawaiian Islands, around Palmyra and Johnston Atolls, and American Samoa. These two species did not have density model outputs within the SERDP/NASA/NOAA and OBIS– SEAMAP database. However, limited OBIS–SEAMAP sightings data exist for these species within or adjacent to the action area. Even where the limited number of sightings suggests that density is very low and encounters are less likely, for any species with OBIS– SEAMAP sightings data within or adjacent to the action area, NMFS believes it is wise to include coverage for potential takes. Generally, to quantify this coverage, NMFS assumed that ExxonMobil could potentially encounter one group of each species during the conductor pipe installation activities, and NMFS thinks it is reasonable to use the average group size to estimate the take from these potential encounters. Therefore, even though we do not have abundance data for these species, because of the limited sightings and low probability of encountering them, we have predicted take of no more than one individual group of each of these species of animals during the conductor pipe installation activities. Qualitatively, given what is known about cetacean biology and the range of these species, one group as a portion of the total population abundance within the U.S. EEZ would be considered small for both species. Endangered Species Act Of the species of marine mammals that may occur in the action area, several are listed as threatened or endangered under the ESA, including the North Pacific right, western North Pacific gray, humpback, sei, fin, blue, and sperm whale and Guadalupe fur seal. ExxonMobil did not request take of endangered North Pacific right whales, western North Pacific gray whales, or Guadalupe fur seals due to the low likelihood of encountering these species during the pipe-driving activities. NMFS’s Office of Protected Resources, Permits and Conservation Division, initiated formal consultation under section 7 of the ESA with NMFS’s West Coast Regional Office, Protected PO 00000 Frm 00033 Fmt 4701 Sfmt 9990 58945 Resources Division, to obtain a Biological Opinion evaluating the effects of issuing the IHA to ExxonMobil under section 101(a)(5)(D) of the MMPA on threatened and endangered marine mammals. NMFS’s Biological Opinion concluded that the action and issuance of the IHA are not likely to jeopardize the continued existence of listed species and included an Incidental Take Statement incorporating the requirements of the IHA as Terms and Conditions. The Biological Opinion also concluded that designated critical habitat of these species does not occur in the action area. National Environmental Policy Act To meet National Environmental Policy Act (NEPA; 42 U.S.C. 4321 et seq.) requirements published by the Council of Environmental Quality (CEQ) and NOAA Administrative Order 126–6, Environmental Review Procedures for Implementing the National Environmental Policy Act, NMFS conducted a NEPA analysis to evaluate the effects of authorizing the take of marine mammals. NMFS prepared an Environmental Assessment titled ‘‘Environmental Assessment on the Issuance of an Incidental Harassment Authorization to ExxonMobil Production Company to Take Marine Mammals by Harassment Incidental to Conductor Pipe Installation Activities at Harmony Platform in the Santa Barbara Channel offshore of California.’’ NMFS has determined that the issuance of the IHA is not likely to result in significant impacts on the human environment and issued a Finding of No Significant Impact (FONSI). Authorization NMFS has issued an IHA to ExxonMobil for the take, by Level B harassment, of small numbers of marine mammals incidental to conducting conductor pipe installation activities at Harmony Platform in Santa Barbara Channel offshore of California, provided the previously mentioned mitigation, monitoring, and reporting requirements are incorporated. Dated: September 19, 2014. Perry F. Gayaldo, Deputy Director, Office of Protected Resources, National Marine Fisheries Service. [FR Doc. 2014–22758 Filed 9–29–14; 8:45 am] BILLING CODE 3510–22–P E:\FR\FM\30SEN3.SGM 30SEN3

Agencies

[Federal Register Volume 79, Number 189 (Tuesday, September 30, 2014)]
[Notices]
[Pages 58913-58945]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2014-22758]

[[Page 58913]]

Vol. 79

Tuesday,

No. 189

September 30, 2014

Part III

Department of Commerce

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National Oceanic and Atmospheric Administration

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Takes of Marine Mammals Incidental to Specified Activities; Taking
Marine Mammals Incidental to Conductor Pipe Installation Activities at
Harmony Platform in Santa Barbara Channel Offshore of California;
Notice

Federal Register / Vol. 79, No. 189 / Tuesday, September 30, 2014 /
Notices

[[Page 58914]]

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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

RIN 0648-XD188

Takes of Marine Mammals Incidental to Specified Activities;
Taking Marine Mammals Incidental to Conductor Pipe Installation
Activities at Harmony Platform in Santa Barbara Channel Offshore of
California

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

ACTION: Notice; issuance of an Incidental Take Authorization (ITA).

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SUMMARY: In accordance with the Marine Mammal Protection Act (MMPA)
regulations, notification is hereby given that NMFS has issued an
Incidental Harassment Authorization (IHA) to the ExxonMobil Production
Company (ExxonMobil), a Division of ExxonMobil Corporation, to take
marine mammals, by Level B harassment only, incidental to installing
six conductor pipes via hydraulic hammer driving at the Harmony
Platform, Santa Ynez Production Unit, located in the Santa Barbara
Channel offshore of California.

DATES: Effective September 17, 2014, through September 16, 2015.

ADDRESSES: A copy of the final IHA and application are available by
writing to Jolie Harrison, Supervisor, Incidental Take Program, Permits
and Conservation Division, Office of Protected Resources, National
Marine Fisheries Service, 1315 East-West Highway, Silver Spring, MD
20910, by telephoning the contacts listed here, or by visiting the
Internet at: https://www.nmfs.noaa.gov/pr/permits/incidental.htm#applications.
NMFS prepared an Environmental Assessment (EA) in accordance with
the National Environmental Policy Act (NEPA), which is also available
at the same Internet address. NMFS also issued a Biological Opinion
under section 7 of the Endangered Species Act (ESA) to evaluate the
effects of the conductor pipe installation activities and IHA on marine
species listed as threatened and endangered. Documents cited in this
notice may be viewed, by appointment, during regular business hours, at
the aforementioned address.

FOR FURTHER INFORMATION CONTACT: Howard Goldstein or Jolie Harrison,
Office of Protected Resources, NMFS, 301-427-8401.

SUPPLEMENTARY INFORMATION:

Background

Sections 101(a)(5)(A) and (D) of the MMPA (16 U.S.C. 1361 et seq.),
direct the Secretary of Commerce (Secretary) to allow, upon request,
the incidental, but not intentional, taking of small numbers of marine
mammals, by United States 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.
An authorization for the incidental takings shall be granted if
NMFS finds that the taking will have a negligible impact on the species
or stock(s), and 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 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 March 3, 2014, NMFS received an application from ExxonMobil for
the taking of marine mammals incidental to installing six conductor
pipes by hydraulic hammering at the Harmony Platform, Santa Ynez
Production Unit, in the Santa Barbara Channel offshore of California.
Along with the IHA application, NMFS received an addendum titled
``Assessment of Airborne and Underwater Noise from Pile Driving
Activities at the Harmony Platform.'' NMFS determined that the
application was adequate and complete on April 28, 2014.
The project's estimated dates are from mid-September to mid-
December 2014, but the planned action could occur anytime within a 12-
month period from the effective date of the IHA. Acoustic stimuli
(i.e., increased underwater and airborne sound) generated during the
conductor pipe installation activities are likely to result in the take
of marine mammals. Take, by Level B harassment only, of 32 species of
marine mammals is anticipated to result from the activities.

Description of the Specified Activity

Overview

ExxonMobil plans to install six conductor pipes by hydraulic
hammering at the Harmony Platform, Santa Ynez Production Unit, in the
Santa Barbara Channel offshore of California.

Dates and Duration

ExxonMobil estimates that the planned conductor pipe installation
activities will occur from mid-September to mid-December 2014, but the
planned activities could occur anytime within a 12-month period from
the effective date of the planned IHA. Precise scheduling is not
presently available due to logistical and regulatory uncertainties. The
estimated duration of the planned project is 91 days. Under normal
working conditions, the planned project is expected to include
approximately 84 days of installation activity on the Harmony Platform
bounded by 7 days of project mobilization/demobilization activities. It
will take approximately 14 days to install each conductor pipe (6
conductors x 14 days = 84 days). Figure 2-1 of the IHA application
includes a timeline of pile-driving activities over the approximate
three month duration.

Specified Geographic Region

Harmony Platform is located in the Santa Barbara Channel, which is
approximately 100 km (54 nmi) long and 40 km (21.6 nmi) wide, situated
between the Channel Islands and the east-west trending coastline of
California. The Santa Barbara Channel is the site of several other
producing oil fields, including Ellwood, Summerland, Carpinteria
offshore, and Dos Cuadras. The Santa Barbara basin is the prominent
feature of the Santa Barbara Channel, with sill depths of approximately
250 m (820.2 ft) and 450 m (1,467.4 ft) at eastern and western
entrances, respectively, with shallow (60 m or 196.9 ft) inter-island
passages to the south. Harmony Platform's geographical position is
34[deg] 22' 35.906'' North, 120[deg] 10' 04.486'' West, at a water
depth of 366 m (1,200.8 ft) on the continental slope below a relatively

[[Page 58915]]

steep (7.5%) descent. The Harmony Platform is 43.5 km (27 miles)
southwest of Santa Barbara, California (see Figure 1 of the IHA
application). It is 4.7 km (2.5 nmi) from the shelf break, which is
typically defined at the 100 m (328.1 ft) isobaths (USGS, 2009). It is
3.3 km (1.8 nmi) from the nearest buffered 200 m (656.2 ft) contour,
which has been noted for its association with higher recorded densities
of cetacean species (Redfern et al., 2013). It is also located 10 to 15
km (5.4 to 8.1 nmi) north of a common traffic route used by vessels to
access the ports of Long Beach and Los Angeles. Figure 1-1 of the IHA
application includes the location of the Harmony Platform, general site
bathymetry, and Santa Barbara area boundaries.

Detailed Description of the Specified Activity

ExxonMobil plans to install six conductor pipes by hydraulic
hammering at Harmony Platform. The conductor pipe installation
activities are estimated to occur from mid-September to mid-December
2014, but the action could occur anytime within a 12-month period from
the effective date of the IHA. Harmony Platform is located 10
kilometers (km) (5.4 nautical miles [nmi]) off the coast of California,
between Point Conception and the City of Santa Barbara. Harmony
Platform is one of three offshore platforms in ExxonMobil's Santa Ynez
Production Unit, and is located in the Hondo field (Lease OCS-P 0190)
at a water depth of 336 meters (1,200.8 ft). Harmony Platform was
installed on June 21, 1989 with the sole purpose of producing crude oil
and gas condensate. It began production of crude oil, gas and gas
condensate on December 30, 1993. A conductor pipe is installed prior to
the commencement of drilling operations for oil and gas wells. It
provides protection, stability/structural integrity, and a conduit for
drill cuttings and drilling fluid to the platform. It also prevents
unconsolidated sediment from caving into the wellbore, and provides
structural support for the well loads. Drilling activities are
currently ongoing at Harmony Platform utilizing the existing conductors
and wells. The platform jacket structure (see Figure 1-2 of the IHA
application) currently has conductors installed in 51 out of 60 slots,
as approved by the Bureau of Ocean Energy Management (BOEM, formerly
the Minerals Management Service [MMS]) in the original Development
Production Plan. Addition of eight straight conductors at the Harmony
Platform was approved by the Bureau of Safety and Environmental
Enforcement (BSEE) on February 11, 2013 to maintain current production
levels from the existing platform. Conductor installation with a
hydraulic hammer is consistent with approved development plans, and is
the same method that was used to install conductors on all three Santa
Ynez Production Unit platforms from 1981 (Hondo) through 1993 (Harmony
and Heritage). Pipe-driving the conductors is the only proven
installation method that enables management of potential interferences
with the existing platform infrastructure that will also reach the
target depth. Non-pipe-driving conductor installation methods are not
deemed feasible at this time due to increased risk to platform
structural integrity, offset well collision, and shallow-hole
broaching.
The total length of a single conductor pipe is approximately 505 m
(1,656.8 ft). Each conductor consists of multiple sections of 66.04
centimeter (cm) (26 inch [in]) diameter steel pipe that will be
sequentially welded end-to-end from an upper deck of the platform (see
Figure 1-2 of the IHA application), and lowered into the 366 m water
column through metal rings (conductor guides) affixed to the jacket
structure that orient and guide the conductor. Once the conductor
reaches the sediment surface, gravity-based penetration (i.e., the
conductor will penetrate the seabed under its own weight) is expected
to reach approximately 30 m (98.4 ft) below the seabed. A hydraulic
hammer (S-90 IHC) with a manufacturer's specified energy range of 9 to
90 kiloJoules (kJ) will be located on the drill deck and used to drive
the conductor to a target depth of approximately 90 to 100 m (295.3 to
328.1 ft) below the seabed; therefore, only roughly 60 m (196.9 ft) of
each 505 m (1,656.8 ft) long conductor pipe will require hydraulic
driving. The S-90 IHC hydraulic hammer will sit on the conductor
throughout pile-driving operations, but a ram internal to the hammer
will stroke back and forth using hydraulic pressure to impart energy to
the conductor. No physical dropping of a weight will be employed to
drive the conductor.
The S-90 IHC hydraulic hammer has an estimated blow rate of about
46 blows per minute. The portion of a complete conductor that must be
actively driven (hammered) into the seafloor consists of 5 to 7
sections, which are sequentially welded end-to-end. Setup and welding
will take 3.5 to 7.3 hours per section, mostly depending on the type of
welding equipment used (e.g., automated welder). Impact hammer pipe-
driving will take an estimated 2.5 to 3.3 hours for each section,
depending primarily on sediment physical properties, which affect
penetration rate. Complete installation of each conductor is estimated
at approximately 14 days based on 24-hour (continuous) operations.
Table 1-1 of the IHA application presents a summary of driving
activities and estimated number of joints [requiring welding] for each
conductor pipe). Figure 1-3 of the IHA application shows the estimated
time in days for each of these activities that are required to install
a single conductor pipe. ExxonMobil conservatively assumes that active
hammering will be 3.3 hours, followed by 7.3 hours of hammer downtime
(i.e., ``quiet time,'' a time at which other activities are performed
in preparation for the next section of pile) over approximately 53
hours (2.2 days) of the approximately 14 days required to install one
conductor pipe. This schedule produces 4.125 days (99 hours) of
cumulated hammer driving for all six conductors over the project
duration. Figure 1-4 depicts the 3.3 hour pile-drive/7.3 hour downtime
cycle for an isolated 24-hour period, showing a maximum of 9.4 hours of
hammer driving. In the event that efficiencies produce a 2.5 hour
drive/3.5 hour downtime cycle, a maximum of 10 hours of hammer pile-
driving could occur in a single 24-hour period. The complete
installation of the conductor pipes is estimated at 14 days of
continuous operation.

Table 1--Summary of Conductor Pipe Installation Activities and Associated Characteristics of Each Conductor Pipe
at Harmony Platform
----------------------------------------------------------------------------------------------------------------
Estimated Estimated
Conductor pipe activity Pipe length (m) number of Pile-driving required number of
joints days \3\
----------------------------------------------------------------------------------------------------------------
Installation level to sea level 49 (160.8 ft) 4 No.................... 2
Sea level to seafloor.......... 366 (1,200.8 ft) 28 No.................... 5.6

[[Page 58916]]

From 0 to ~30 m below seafloor. 30 \1\ (98.4 ft) 3 No.................... 0.9
From ~30 m to ~90 m below 60 (196.9 ft) 5 to 7 Yes \2\............... 0.69
seafloor.
Hammer downtime................ NA NA No.................... 1.52
Clean up and completion........ NA NA No.................... 3.6
----------------------------------------------------------------------------------------------------------------
\1\ Estimated range of gravity-based penetration.
\2\ See Figure 1-4 of the IHA application.
\3\ See Figure 1-3 of the IHA application.

NMFS provided a detailed description of the planned activities in a
previous notice for the proposed IHA (79 FR 36743, June 30, 2014). The
activities to be conducted have not changed between the proposed IHA
notice and this final notice announcing the issuance of the IHA. For a
more detailed description of the authorized action, including site
bathymetry and sediment physical characteristics, hydrodynamics and
water column physical properties, platform and acoustic source
specifications, metrics, characteristics of sound sources, predicted
sound levels of impact hammer pile-driving, etc., the reader should
refer to the notice of the proposed IHA (79 FR 36743, June 30, 2014),
the IHA application, addendum, and associated documents referenced
above this section.

Comments and Responses

A notice of the proposed IHA for ExxonMobil's conductor pipe
installation activities was published in the Federal Register on June
30, 2014 (79 FR 36743). During the 30-day public comment period, NMFS
received comments from approximately 4,700 private citizens (as
supporters of SierraRise and Sierra Club), Center for Biological
Diversity (CBD), California Coastal Commission (CCC), and the Marine
Mammal Commission (Commission). The comments are online at: https://www.nmfs.noaa.gov/pr/permits/incidental/. Following are the substantive
comments and NMFS's responses:

MMPA Concerns

Comment 1: The Commission states that the densities used to
estimate the numbers of takes were derived using two different methods.
For humpback, blue, and fin whales, ExxonMobil and NMFS stated that
they used densities from Redfern et al. (2013) because those data were
derived in the same project area--the Santa Barbara Channel. However,
the estimated densities for blue and fin whales in the Federal Register
notice do not match the upper boundary of the density contours from
Redfern et al. (2013), which are shown in Table 6-3 and 6-4 of
ExxonMobil's IHA application. Those figures indicate that the density
should be 0.006 whales/km\2\ (not 0.008) for blue whales and 0.0065
whales/km\2\ (not 0.004) for fin whales. Therefore, the Commission
recommends that NMFS revise the density estimates for blue and fin
whales to reflect the density information from Redfern et al. (2013).
Response: NMFS concurs with the Commission's recommendation. The
densities of blue and fin whales in the IHA application and the notice
of the proposed IHA (79 FR 36743, June 30, 2014) are slightly below the
upper boundary contours displayed in Redfern et al. (2013). NMFS agrees
that the density estimates should be 0.006 for the blue whale and
0.0065 for the fin whale. These minor corrections to the density
estimates have only a minor effect on the calculated takes by Level B
harassment, as shown in the table below. However, NMFS has increased
the authorized takes for fin and blue whales to account for group size.

Table 2--Proposed and Corrected Density Estimates for Two of the Species/Stocks Proposed To Be Taken Incidental
to ExxonMobil's Conductor Pipe Installation Activities
----------------------------------------------------------------------------------------------------------------
Calculated takes/
Density estimates requested takes
from Table 5 of Corrected from Table 5 of Corrected
Species the Federal density from the Federal calculated takes/
Register notice Redfern et al. Register notice authorized
of the proposed (2013) of the proposed takes
IHA IHA
----------------------------------------------------------------------------------------------------------------
Fin whale (Balaenoptera physalus)... 0.004 0.0065 0.005/1 0.00392/2
Blue whale (Balaenoptera musculus).. 0.008 0.006 0.011/1 0.000362/2
----------------------------------------------------------------------------------------------------------------

Comment 2: The Commission states that for the species/stocks that
are derived from Redfern et al. (2013), ExxonMobil and NMFS derived
density estimates by dividing each species/stock's abundance estimate
by the area of the Santa Barbara Channel (12,593 km\2\). The abundance
estimates used by NMFS (in Table 5 of the notice of the proposed IHA
[79 FR 36743, June 30, 2014]) were different from those used by
ExxonMobil (in Table 3-1 of its IHA application). Although the reason
for this discrepancy is not provided, it appears to the Commission that
the abundance estimates in Table 5 of the Federal Register notice of
the proposed IHA (79 FR 36743, June 30, 2014) were taken from the NMFS
2013 Pacific Stock Assessment Report (Carretta et al., 2013). However,
NMFS's derived density estimates were incorrect for four of the species
identified. Table 3 (below) lists the four marine mammal species in
question, NMFS's density estimates, and the Commission's corrected
densities, based on the abundance estimates provided by NMFS in Table 5
of the Federal Register notice of the proposed IHA (79 FR 36743, June
30, 2014).

[[Page 58917]]

Table 3--Proposed and Corrected Density Estimates, in Animals/km\2\, for
Four of the Species/Stocks Proposed To Be Taken Incidental to
ExxonMobil's Conductor Pipe Installation Activities
------------------------------------------------------------------------
Corrected density
Density estimates estimates, derived
from Table 5 of from abundance
the Federal estimates in
Species Register notice Table 5 of the
of the proposed Federal Register
IHA notice of the
proposed IHA
------------------------------------------------------------------------
Gray whale...................... 0.5067 1.519
Cuvier's beaked whale........... 0.17 0.523
Mesoplodon spp.................. 0.08 0.055
Bottlenose dolphin.............. 0.11 0.080
------------------------------------------------------------------------

Therefore, the Commission recommends that NMFS revise the density
estimates for gray whales, Cuvier's beaked whales, Mesoplodon spp., and
common bottlenose dolphins to reflect the best available abundance
estimates from Carretta et al. (2013); the corrected density estimates
should then be used in NMFS's revised take estimates.
Response: The differences in the calculated densities reported in
the IHA application (Tables 3-1 and 6-1 and the notice of the proposed
IHA (79 FR 36743, June 30, 2014) were largely due to differences in
abundance estimates and/or assumptions on seasonal variability (gray
whale only), or due to combining abundance estimates of closely related
stocks of selected species (e.g., killer whales). Where available, NMFS
uses the abundance estimates for NMFS 2013 Pacific Stock Assessment
Report (Caretta et al., 2013). Therefore, NMFS concurs with the
Commission's recommendation regarding gray whales, Cuvier's beaked
whales, Mesoplodon spp. beaked whales, and bottlenose dolphins, and has
revised the abundance estimates and associated calculated and corrected
density estimates. NMFS notes that these corrections produce little or
no change in the number of calculated takes by Level B harassment for
each of the identified species. An explanation of the density estimates
and authorized take for each of the four species referenced in the
Commission's comments follows:
The gray whale density in the notice of the proposed IHA
(79 FR 36743, June 30, 2014) is incorrect and should be approximately
1.5, based on the NMFS 2013 Stock Abundance Report. However, the
corrected density estimate produces no change in the estimated take of
10 animals, which was increased (made more conservative based on group
size and the schedule moving into the fall season, which is a higher
density time period to account for the southward migration.
The Cuvier's beaked whale density estimate in the notice
of the proposed IHA (79 FR 36743, June 30, 2014) is incorrect and
should be approximately 0.523. The notice of the proposed IHA also gave
an incorrect abundance estimate for this species (6,950). The abundance
of Cuvier's beaked whale abundance is 6,590 based on NMFS 2013 Stock
Abundance Report (Caretta et al., 2013). Based on the corrected density
estimate of 0.523 and a corrected abundance estimate of 6,590 animals,
NMFS estimates that approximately 4 animals may be taken.
NMFS provided a density estimate of 0.08 for the
Mesoplodon spp. beaked whale in the notice of the proposed IHA (79 FR
36743, June 30, 2014) based on an abundance of 1,024. Using the
abundance estimate of 694 in the NMFS 2013 Stock Assessment Report,
NMFS agrees with the Commission that the density estimate is 0.0551.
This produces an estimated calculated take of approximately 1 animal
using either abundance estimate. However, NMFS is authorizing take of 2
animals based on group size.
The bottlenose dolphin density estimate in the notice of
the proposed IHA (79 FR 36743, June 30, 2014) is incorrect and should
be approximately 0.08, based on the offshore abundance of the stock.
Common bottlenose dolphin densities in the IHA application and notice
of the proposed IHA (79 FR 36743, June 30, 2014) were 0.11 based on an
abundance of 1,329, derived from combining the coastal and offshore
stocks (323 + 1,006). However, California coastal bottlenose dolphins
are found within one km (0.54 nmi) of shore primarily from Point
Conception south into Mexican waters, at least as far south as San
Quintin, Mexico; therefore, we do not expect the coastal stock to be
taken by the conductor pipe installation activities and do not consider
this stock further in this analysis (Hansen, 1990; Caretta et al.,
1998; Defran and Weller, 1999). In southern California, animals are
found within 500 m (0.27 nmi) of shoreline 99% of the time and within
250 m (0.13 nmi) 90% of the time (Hanson and Defran, 1993). The
original calculated take estimates for bottlenose dolphins was 0.15,
based on a density of 0.11. The corrected calculated take estimate is
0.4829, based on the corrected density of 0.0799. However, the
corrected density estimate produces no change in the estimated take of
10 animals, which was increased (made more conservative) based on group
size.
Comment 3: The Commission states that ExxonMobil estimated the
numbers of marine mammal takes by multiplying the species specific
densities by the area of the Level B harassment buffer zone (0.3188
km\2\) and the duration of the proposed conductor pipe installation
activities. ExxonMobil calculated the latter as a total of 4.125 days
for all six conductor pipes, apparently by summing each period of
proposed conductor pipe installation activities and then dividing that
cumulative exposure time by 24 hours to determine the number of days of
exposure. Because pipe-driving sessions are interspersed between
periods of no pipe-driving, summing across only pipe-driving periods
underestimates the number of days of actual exposure. Instead,
ExxonMobil should have summed across the entire pipe-driving timeframe,
which includes period of no pipe-driving to determine the number of
days animals would be exposed, because each day of pipe-driving has the
potential to expose either the same animals repeatedly or different
animals.
The Commission states that the take estimates should account for
multiple days of exposure rather than aggregated hours of exposure. In
this instance, ExxonMobil should have added 3.3 hours of estimated
pile-driving per section to 7.3 hours of downtime per

[[Page 58918]]

section for a total of 10.6 hours per section of pipe. Multiplying that
by the projected seven sections to be driven for each conductor pipe
would result in a total of 74.2 hours, which when divided by 24 hours
per day equated to 3.1 days of potential exposure per pipe. Using that
method would yield a total of 18.6 days of potential exposure (3.1 days
per conductor pipe multiplied by 6 pipes), which more accurately
represents the total duration of proposed conductor pipe installation
activities for all six conductor pipes. Accordingly, the Commission
recommends that NMFS revise its take estimates for all species/stocks
to account for the total number of days of potential exposure (i.e.,
18.6 days), ensuring a more accurate estimate of potential takes.
The CBD also states that NMFS underestimates the impacts as the
planned conductor pipe installation activities are intermittent and not
continuous as described in the notice of the proposed IHA (79 FR 36743,
June 30, 2014). Authorizing take based on this assumption
underestimates actual take, which would occur over a much greater
amount of time as it could impact communication and navigation of
marine mammals in the action area.
Response: NMFS concurs with the Commission's recommendations and
has revised the take calculations to account for 18.6 days of potential
exposure. See Table 7 for the updated re-calculated take estimates and
authorized take numbers.
Comment 4: The Commission states that ExxonMobil adjusted its take
estimates by a factor of at least 10 for a number of species to account
for group size. NMFS based its proposed take estimates on ExxonMobil's
requested takes for all species except two--sperm whales and short-
beaked common dolphins. NMFS proposed takes for a single sperm whale
and 45 common dolphins, derived directly from density estimates with no
adjustment for group size. Those two species typically occur in groups
that may exceed the requested numbers of takes. Sperm whales typically
occur in groups of 2 to 10 whales (Barlow et al., 2005), and common
dolphins occur in groups of hundreds to thousands of animals (Reeves et
al., 2002). If those species were to be observed in the vicinity of the
project area, they likely would occur in numbers that exceed the
requested number of takes. That could result in actual takes exceeding
the authorized numbers of takes and/or premature shut-down of the
proposed activities. In other similar situations, NMFS has increased
the requested number of takes of a particular species to reflect the
mean group size of that species (e.g., Table 4 in 78 FR 33811).
Therefore, to ensure that the requested numbers of takes reflect
numbers of individuals of each species that may be observed in the
project area, the Commission recommends that NMFS increase its
estimated numbers of takes for sperm whales and short-beaked common
dolphins to reflect the minimum typical group size for each species
(i.e., at least 2 and 450 animals, respectively).
Response: NMFS concurs with the Commission's recommendation and has
increased the takes of sperm whales and short-beaked common dolphins
from 1 and 45 to 2 and 450, respectively. NMFS has also increased the
authorized take numbers for humpback (from 1 to 2), minke (from 1 to
2), sei (from 1 to 2), fin (from 1 to 2), blue (from 1 to 2), Baird's
beaked (from 1 to 6), Cuvier's beaked (from 1 to 4), Mesoplodon spp.
(from 1 to 2), killer (from 1 to 10), and short-finned pilot whales
(from 1 to 40) as well as northern right whale dolphins (from 1 to 100)
to account for average group size (Jefferson et al., 2008).
Comment 5: The CBD states that NMFS underestimates the harmful
impact of the proposed conductor pipe installation activities on
endangered blue whales. The Santa Barbara Channel is important blue
whale habitat. The global blue whale population has been reduced by
commercial whaling from over 300,000 to likely fewer than 10,000
individuals. Blue whales off California are part of a population
comprised of about 1,647 animals; scientists estimate that even three
human-caused deaths each year will impede the recovery of the
California population. Nine blue whales have died from collisions with
ships from 2007 to 2011; this means that human-caused mortality of blue
whales already exceeds the sustainable amount.
Response: NMFS fully considered the potential impacts of the
planned conductor pipe installation activities on endangered blue
whales. As described in the notice of the proposed IHA (79 FR 36743,
June 30, 2014), NMFS anticipates only low level disturbance of blue
whales, if any, in the form of Level B harassment. NMFS is authorizing
take of two blue whale by Level B harassment only; no injury, serious
injury, or mortality is anticipated or authorized. The potential
impacts of the conductor pipe installation activities are expected to
be temporary and are is not expected to have adverse consequences on
the affected stock, including reductions in reproduction, numbers, or
distribution that might appreciably reduce the stock's likelihood of
surviving and recovering in the wild.
NMFS's Office of Protected Resources, Permits and Conservation
Division, also initiated and engaged in formal consultation under
section 7 of the ESA with NMFS's West Coast Regional Office, Protected
Resources Division, on the issuance of an IHA under section
101(a)(5)(D) of the MMPA for this activity. NMFS's West Coast Regional
Office, Protected Resources Division issued a Biological Opinion
addressing the effects of the proposed action on threatened and
endangered species, including the blue whale. The Biological Opinion
concluded that the proposed action is not likely to jeopardize the
continued existence of the blue whale.
Comment 6: The CBD states that blue whales congregate throughout
the Santa Barbara Channel (it hosts the world's densest summer seasonal
congregation), and Harmony Platform is in the region that is an
important area for blue whales. A recent tagging study determined the
areas of highest use by blue whales off the West Coast. Researchers
tagged 171 blue whales between 1993 and 2008, and the area of highest
use was the western area in the Santa Barbara Channel (see Figure 1 of
CBD's comments). The study showed that blue whales use the entire area
of waters in southern California, but that the Santa Barbara Channel is
the most heavily used. Between June and November, high densities of
blue whales spend time feeding on the abundant planktonic krill in the
area of this project (see Figure 2 of CBD's comments). The blue whales
use the project area for foraging, and the conductor pipe installation
activities will interfere with this important life function. Blue
whales will be exposed to sounds that could have auditory damage, but
could also be displaced from important foraging grounds.
Response: Harmony Platform, which is located at 34 22'35.906''
North and 120 10'04.48 West, is on the coastal side of the shipping
lane in the Santa Barbara Channel (see Figure 1-1 of the IHA
application). Based on Figure 1 from CBD's letter (adapted from Irvine
[2014]), this location is in the lowest density area of blue whales in
the U.S. Exclusive Economic Zone near the Channel Islands based on
satellite tracks, with only 1 to 5 blue whales observed from 1998 to
2008. The highest density area (20 to 26 blue whales) shown in Figure 1
of CBD's letter is located further offshore from the shipping channel,
and roughly coincides with the area of highest krill density in the
California Current reported by Santora et al. (2011), which is
approximately 30 to 50 km (16.2 to 27

[[Page 58919]]

nmi) from Harmony Platform. These distribution correlations are
expected given that krill comprise the majority of the blue whale's
diet, and indicate that blue whales rarely forage or congregate within
5 to 10 km (2.7 to 5.4 nmi) of Harmony Platform, which is well outside
of the expected 325 m buffer zone for Level B harassment. NMFS
anticipates only low level disturbance of blue whales, if any, in the
form of Level B harassment, as Harmony Platform is located in an area
of lowest blue whale density and second lowest krill density in the
California Current (see Santora et al., 2011, Figure 5). NMFS does not
expect the conductor pipe installation activities to displace blue
whales from foraging grounds.
Comment 7: CBD states that new science shows that blue whales, and
possible other baleen whales, are highly susceptible to behavioral
disturbance from noise pollution. The Goldbogen et al. (2013) study
raises substantial concern because it demonstrates the potential
impacts of high intensity noise on the essential life functions of blue
whales. The study found that mid-frequency sonar can disrupt feeding
and displace blue whales from high-quality prey patches, significantly
impacting their foraging ecology, individual fitness, and population
health. Even fairly low-received levels can have an adverse impact.
Response: The Goldbogen et al. (2013) study analyzed behavioral
responses of tagged blue whales in response to simulated military sonar
and other mid-frequency sounds used during a controlled exposure
experiment in feeding areas within the Southern California Bight. The
study concluded that the responses of animals to mid-frequency sonar
were complex, dependent on the behavioral state and sound exposure
factors, and represented a general avoidance response of a perceived
threat that appeared to subside quickly after sound exposure.
ExxonMobil's conductor pipe installation activities would not generate
the same sound characteristics as the military sonar and other mid-
frequency sounds that were used during those controlled exposure
experiments. Moreover, the IHA requires ExxonMobil to implement
monitoring and mitigation measures to avoid exposing marine mammals,
including blue whales, to sounds levels that could have potential
adverse impacts. As described in the notice of the proposed IHA (79 FR
36743, June 30, 2014), NMFS anticipates only low level disturbance of
marine mammals in the form of Level B harassment from ExxonMobil's
activities. NMFS does not anticipate significant impacts to the
foraging behavior, individual fitness, or population health of blue
whales in the action area.
Comment 8: The CBD states that the best available science indicates
western North Pacific gray whales may be present in the survey area.
Recently, a tagged western North Pacific gray whale traveled all the
way from Sakhalin Island, Russia, to the west coast of North America,
indicating that the population may merge with the eastern North Pacific
population during migration and may therefore be taken by activity.
There are currently an estimated 155 western North Pacific gray whales
left in the world. With such low population numbers, the take of even
one of these whales would have greater than negligible impacts on the
species or stock.
Response: Western North Pacific gray whales are not expected to
occur in the action area. There is evidence of movement between
``eastern'' and ``western'' populations of North Pacific gray whales,
but the evidence thus far only supports low inter-area movements. For
gray whales that migrate along the continental U.S., evidence from
photo-identification work supports only seven confirmed western gray
whale sightings (as well as a single satellite-tracked individual) ever
in the central and eastern Pacific Ocean compared to roughly 20,000
individuals composing the eastern North Pacific population, which has
been tracked for decades (Mate et al., 2011; Burdin et al., 2011;
Weller et al., 2011). These sightings occurred along Alaska,
Washington, and Oregon, where foraging could occur. Urban et al. (2012)
matched 13 individuals through photo-identification between summer
feeding grounds in Russia and winter breeding lagoons in Mexico. The
only motivation for an individual to continue further south (beyond
foraging opportunities) is to participate in breeding and calving in
lagoons of Baja California (Mexico) and the Gulf of California.
However, numerous studies have found that genetic exchange between
eastern and western populations is not occurring to a significant level
(Leduc et al., 2002; Lang et al., 2004; Weller et al., 2004b; Lang et
al., 2005; Swartz et al., 2006; Weller et al., 2006a; Weller et al.,
2007; Brownell Jr. et al., 2009; Kanda et al., 2010; Lang et al.,
2010b; Burdin et al., 2011). Moore and Weller (2012) determined the
probability of taking a single gray whale from the western population
during the proposed Makah Indian Tribe hunt as 0.014 to 0.051 during a
single year. NMFS does not expect western North Pacific gray whales to
occur in the action area due to the lack of documented trans-Pacific
movement (particularly as far as the action area) as well as the lack
of rationale for gray whales from the western population to move
through the area.
Comment 9: The CBD states that the North Pacific right whale is a
potentially impacted species for which no take may be authorized. There
are an estimated 25 to 30 individuals in the eastern stock of North
Pacific right whales, making it the most highly endangered large whale
in the world (Wade et al., 2011). Although NMFS notes that North
Pacific right whales may be present in the project area, it assumes,
without support, that no North Pacific right whales will be taken.
Response: The North Pacific right whale is rarely found off the
U.S. west coast. The majority of North Pacific right whale sightings
from the eastern North Pacific stock occur in the Bering Sea and
adjacent areas of the Aleutian Islands and Gulf of Alaska. Sightings of
this species have been reported as far south as central Baja California
in the eastern North Pacific, as far south as Hawaii in the central
North Pacific, and as far north as the sub-Arctic waters of the Bering
Sea and Sea of Okhotsk in the summer. Data from passive acoustic
monitoring indicates that North Pacific right whales are present year-
round in the southeastern Bering Sea, with peaks in the late summer
(August to September). Although individuals may travel south from the
high-latitudes of the Bering Sea to lower-latitudes, animals that have
been sighted in waters off Hawaii or tropical Mexico have been
considered extralimital for this species (Brownell et al., 2001). The
North Pacific right whale has not been observed near Harmony Platform.
Therefore, no takes of North Pacific right whales are anticipated or
authorized by NMFS. Although North Pacific right whales are not
expected to occur in the action area, NMFS's Office of Protected
Resources, Permits and Conservation Division also considered the
conservation status, rarity, and habitat of ESA-listed marine mammals
(including the North Pacific right whale) when developing mitigation
measures for the conductor pipe installation activities. Included in
the IHA are special procedures for situations or species of concern
(see ``Mitigation'' section below). If a North Pacific right whale is
visually sighted during the conductor pipe installation activities, the
pipe-driving activities must be shut-down regardless of the distance of
the animal(s) to the sound source. The pipe-driving will not resume
firing until 30

[[Page 58920]]

minutes after the last documented whale visual sighting.
Comment 10: The CBD states that sperm whales reach peak abundance
in California from April through mid-June and from the end of August
through mid-November, which is during the time of the proposed
conductor pipe installation activities. Any take of a sperm whale would
have greater than negligible impacts on the stock because NMFS must
take into account the cumulative take of sperm whales from other
activities, including incidental catch by fisheries. The California
drift gillnet fishery, which operates primarily in southern California
from August through January, took an estimated sixteen endangered sperm
whales in the 2010 to 2011 fishing season (Caretta and Enriquez, 2012).
Including both fishery and ship-strike mortality, the average annual
rate of kill and serious injury is four sperm whales, exceeding the
potential biological removal level of 1.5 (Caretta et al., 2012). With
an estimated 971 sperm whales in the population, this level of
anthropogenic take cannot be considered a negligible impact.
Response: Sperm whale abundance varied off California between 1979/
1980 and 1991 (Barlow, 1994) and between 1991 and 2008 (Barlow and
Forney, 2007). The most recent estimate from 2008 is the lowest to
date, in sharp contrast to the highest abundance estimates obtained
from NMFS's 2001 and 2005 surveys. However, there is no reason to
believe that the population has declined; the most recent survey
estimate likely reflects inter-annual variability in the study area. To
date, there has not been a statistical analysis to detect trends in
abundance. NMFS's 2013 Stock Assessment Report estimated a sperm whale
abundance of 971 individuals for the California/Oregon/Washington
stock. A new analysis by Moore and Barlow (in press) estimates a
population abundance of approximately 21,31 animals (1,332 minimum).
NMFS expects potential impacts by Level B harassment only to sperm
whales; no injury, serious injury, or mortality is anticipated or
authorized. The potential impacts are expected to be temporary and the
action is not expected to have adverse consequences on the stock,
including reductions in reproduction, numbers, or distribution that
might appreciably reduce the stock's likelihood of surviving and
recovering in the wild. Based on our analysis of the likely effects of
the action on sperm whales and their habitat, and taking into
consideration the implementation of the required monitoring and
mitigation measures (see ``Mitigation'' below), NMFS finds that the
take of small numbers of sperm whales by Level B harassment incidental
to ExxonMobil's conductor pipe installation activities will have a
negligible impact on the affected marine mammal species or stocks.
NMFS's Office of Protected Resources, Permits and Conservation
Division, also initiated and engaged in formal consultation under
section 7 of the ESA with NMFS's West Coast Regional Office, Protected
Resources Division, on the issuance of an IHA under section
101(a)(5)(D) of the MMPA for this activity. NMFS's West Coast Regional
Office, Protected Resources Division issued a Biological Opinion
addressing the effects of the proposed action on threatened and
endangered species, including the sperm whale. The Biological Opinion
concluded that the proposed action is not likely to jeopardize the
continued existence of the sperm whale.
Comment 11: The CCC states that sea surface temperatures off of
southern California and in the eastern north Pacific Ocean at large
have been above normal for several months, and with an apparent El Nino
event emerging in the equatorial Pacific Ocean later this year, are
likely to remain elevated through the fall, winter, and into 2015. As a
consequence of the unusually warm waters, marine mammal species more
typical of subtropical latitudes have been sighted off of southern
California and in the Santa Barbara Channel. These species may continue
to be present in numbers and locations beyond those that can be
reflected accurately by density estimates derived from long term survey
and abundance datasets. These include cetaceans such as Bryde's whales
(Balaenoptera brydei), false killer whales (Pseudorca crassidens), and
short-finned pilot whales (Globicephala macrorhynchus), which have
rarely been seen off the California coast in recent years. In light of
these unusual environmental conditions, it may be necessary for NMFS to
consider whether additional species could be exposed to the conductor
pipe installation activities, and to revisit the species abundance
assumptions underlying its incidental take calculations for the species
already evaluated in the proposed IHA.
Response: NMFS has received anecdotal reports from the public,
whale watching companies, and other sources of recent sightings of
Bryde's, false killer, and short-finned pilot whales. As discussed in
the notice of the proposed IHA (79 FR 36743, June 30, 2014), these
three species are generally found south of the Santa Barbara Channel
and are unlikely to be found in the action area. Bryde's whales are
extremely rare in the Southern California Bight, with fewer than ten
confirmed sightings from August 2006 to September 2010 (Smultea et al.,
2012). NMFS West Coast Regional Office has received reports of up to 4
individual Bryde's whales sighted in the summer of 2014 and has had a
total of 12 sightings ever documented in the past. NMFS West Coast
Regional Office has received reports of up to 40 short-finned pilot
whales sighted off the Channel Islands and elsewhere. A group of
approximately 50 short-finned pilot whales were sighted off the coast
of Dana Point in Orange County in June 2014. A group of approximately
40 to 70 false killer whales were sighted off the coast of Dana Point
in March 2014. NMFS concurs with the CCC's recommendation and has
authorized take, by Level B harassment, for Bryde's, false killer, and
short-finned pilot whales based on the possibility of encountering a
single individual Bryde's whale or a group of false killer and/or
short-finned pilot whales in the action area of the planned conductor
pipe installation activities at Harmony Platform. NMFS has also
revisited the species abundance assumptions for all of the marine
mammal species and has adjusted density estimates for those that occur
in the California Current ecosystem. See Table 7 for the revised
density estimates and authorized take numbers for these marine mammal
species.
Comment 12: The CBD is concerned with NMFS's conclusion to exclude
consideration of Guadalupe fur seals, which are rarely sighted animals
with ranges within the action area.
Response: NMFS does not expect Guadalupe fur seals to be in the
immediate action area or exposed to sounds generated by the conductor
pipe installation activities. Guadalupe fur seals occur primarily near
Guadalupe Island, Mexico, their primary breeding area. They are found
north of the U.S.-Mexican border with a very small number of adults and
pups observed on San Miguel Island (the western-most Channel Island in
the Southern California Bight). Guadalupe fur seal strandings have
occurred in California and north into Washington, which indicates that
they must transit through southern California from Mexico to these
areas where they have stranded. However, the encounter rate in the
action area is considered to be very low. While they could potentially
transit through the general area, NMFS considers it unlikely that they
would be exposed to levels of sound associated

[[Page 58921]]

with take, given their rare occurrence in the area, the duration of the
activities, and the size of the ensonified area.

Mitigation

Comment 13: The CBD states that the mitigation measures are
inadequate to ensure the least practicable adverse impact. If NMFS
decides to approve the action it must require additional monitoring and
mitigation measures to implement the least practicable impact on marine
mammals.
Response: NMFS's Office of Protected Resources, Permits and
Conservation Division considered a number of mitigation measures before
issuing the IHA, including measures proposed by ExxonMobil and
additional measures recommended by the public. NMFS's Office of
Protected Resources, Permits and Conservation Division has determined
that the monitoring and mitigation measures required by the IHA provide
the means of effecting the least practicable impact on species or
stocks and their habitat, paying particular attention to rookeries,
mating grounds, and areas of similar significance.
Comment 14: The CBD states that NMFS must fully analyze time-area
restrictions as a mitigation measure. NMFS must not allow pipe-driving
when blue whales aggregate in the Santa Barbara Channel during June
through November. The western portion of the Santa Barbara Channel,
where Harmony Platform is located, provides a core area for the blue
whales, and pipe-driving should be restricted in this important habitat
for blue whales. This closure should further be extended to avoid
overlap with the presence of other whales.
Response: NMFS disagrees with the CBD that time-area restrictions
are necessary as a mitigation measure. The Harmony Platform is located
at 34 22' 35.906'' North and 120 10' 04.48'' West, on the coastal side
of the shipping lane in the Santa Barbara Channel (see Figure 1 of the
IHA application). Based on Figure 1 in CBD's comment letter (adapted
from Irvine, 2014), this location is in the lowest density of blue
whales in the U.S. Exclusive Economic Zone near the Channel Islands
based on satellite tracks, with only 1 to 5 blue whales observed from
1998 to 2008 (yellow zone in Figure 1). The highest density area shown
in Figure 1 (20 to 26 blue whales) is located further offshore from the
shipping lane, and roughly coincides with the area of highest krill
density in the California Current reported by Santora et al. (2011),
which is approximately 30 to 50 km from Harmony Platform. These
distribution correlations are expected given that krill comprise the
majority of the blue whale's diet, and indicate that blue whales rarely
forage or congregate within 5 to 10 km of Harmony Platform. Therefore,
given that the areas of highest blue whale density and krill density
near the Channel Islands are well outside the 325 m buffer zone for the
pipe-driving activities, NMFS disagrees that time-area restrictions for
the blue whale are necessary.
Comment 16: The CBD states that NMFS must fully analyze larger
exclusion zones as a mitigation measure. The use of more accurate
thresholds would lead to larger exclusion zones. Additionally, the
modeled distances disagree with measured sound levels for other pile-
driving activities. The exclusion zone of 3.5 m for pinnipeds and 10 m
for cetaceans is woefully inadequate to mitigate Level A harassment.
Bailey et al. (2010) measured 205 dB of broadband sound at 10 m from
the pile-driving source. While the source was louder at 226 dB in that
study, it indicates that the exclusion zone should be much larger.
Response: NMFS disagrees with the CBD's comment. For a response to
CBD's comment regarding NMFS' thresholds for Level A harassment, see
the response to comment 21 (below) X. NMFS and ExxonMobil are not aware
of any available in-situ measurements of underwater sound using a 90 kJ
impact hammer with a 66 cm (26 in) diameter steel, 426.7 to 457.2 m
(1,400 to 1,500 ft) pipe, in which case, acoustic modeling is an
appropriate and oft-used scientifically defensible method available to
estimate the buffer and exclusion zones established for potential
impact and mitigation purposes. A detailed acoustic modeling report by
JASCO titled ``Assessment of Airborne and Underwater Noise from Pile
Driving Activities at the Harmony Platform'' was provided to NMFS with
the IHA application, and includes detailed information on the computer
model, uncertainties, and associated input parameters used to calculate
distance to the buffer (Level B harassment) and exclusion (Level A
harassment) zones. NMFS evaluated the report and determined that it
provided sufficient support to establish predicted buffer and exclusion
zones. Moreover, these predicted underwater and in-air sound levels
will be assessed for accuracy when the monitoring data is analyzed
after installation of the first conductor pipe, and the buffer and
exclusion zones will be revised as necessary for the installation of
the remaining pipes based on the results of the sound source
verification.
Bailey et al. (2010) assessed the potential effects of underwater
noise levels during pile-driving at an offshore windfarm on marine
mammals; however, the piles and pile-driving technical details as well
as the sound analysis in that study are different than those planned to
be used during ExxonMobil's conductor pipe installation activities. The
Bailey et al. (2010) study was conducted for the installation of wind
turbines using much shorter ``piles'' in water depths of approximately
40 m (131.2 ft) (hammer specifications unknown); therefore, the
underwater and in-air noise estimates and corresponding buffer and
exclusion zones are not comparable between the two projects. This is
because underwater sound propagation is a function of sound source
energy and frequency, water depth and physical structure (e.g.,
salinity, temperature), bottom sediment type (hardness, porosity), and
pipe material (e.g., steel, concrete) and size; all of which differ
between the Bailey et al. (2010) site and the Harmony Platform site.
Comment 16: The CBD states that NMFS must fully analyze air bubble
curtains, which can reduce sound by 20 to 30 dB depending on their
design, or explore the use of other noise reduction technologies (e.g.,
pile caps, dewatered cofferdams, and other physical barriers) for
mitigating underwater sound from impact hammer pipe-driving.
Response: NMFS and ExxonMobil evaluated the potential use of air
bubble curtains to reduce the underwater sound generated during pipe-
driving activities in a water depth of 365.8 m (1,200 ft). The use of
an air bubble curtain is not feasible due to interference of the jacket
infrastructure at Harmony Platform, and the water depth and current
speed (greater than 10 meters per second) at the activity site, which
prevents the ability to maintain a constant air bubble density along
the conductor length that would be effective at reducing underwater
sound from the conductor pipe installation activities. The conductor
pipes are being installed in 365.8 m of water through 76.2 cm (30 in)
guides that are attached to structural members on the Harmony Platform;
therefore, an air bubble curtain would be ineffective at reducing the
output sound level, as bubbles would be dispersed and carried by
currents away from the pipe and redirected by interference from the
surrounding jacket members and conductor infrastructure. Because the
conductors pass through 365.8 m of water column, another issue that
eliminated this sound reduction

[[Page 58922]]

technique from consideration was that the air nozzles used to generate
the air bubbles would most likely freeze-up before reaching the sea
bottom due to the pressure and cold temperatures of the water, which
would render the air bubble curtain ineffective. All known applications
of air bubble curtains that have effectively reduced sound by 20 to 30
dB have been used at depths shallower than 365.8 m and in waters with
current velocities that are less than those commonly encountered in
Santa Barbara Channel.
NMFS and ExxonMobil also evaluated the potential use of a dewatered
cofferdam to reduce the underwater sound generated during conductor
pipe installation activities. The installation of a dewatered cofferdam
around each conductor installation is not feasible due to the 365.8 ft
water depth and corresponding pressure. In addition, each conductor has
a limited footprint and has subsea interference from the jacket
infrastructure. Also, a cofferdam would have to be driven into the sea
bottom at a depth of 365.8 m to provide structural stability and
protection from water currents, which would create additional potential
impacts to marine mammals in the action area.
NMFS and ExxonMobil also explored a physical noise abatement
technology using flexible air-filled resonators that are lowered in
multiple long hoses along the sides of each conductor prior to
conductor pipe installation activities. The resonators would be filled
with air in a hose-like structure that would close the gap around the
conductors. This technology is not fully developed, and the scale of
this noise abatement system would be unprecedented and impossible to
install around Harmony Platform. The deepest known noise abatement
system was installed in approximately 36.6 m (120 ft) of water, which
is just one tenth of the depth where the planned conductor pipe
installation activities will occur. This technology also has the same
limitations as a bubble curtain, in that it uses air as the delivery
system to fill the resonator and attenuate sound. At a water depth of
365.8 m, air would likely form hydrates prior to filling the
resonators, which would render this approach ineffective.
Comment 17: The CBD states that NMFS must fully analyze and should
restrict conductor pipe installation activities so that they do not
occur during low visibility. The action is a 24-hour, continuous
activity with pipe-driving potentially happening at night and during
low visibility. The PSOs are ineffective at night and during low
visibility. This means that during those times the exclusion zone will
not be effective in mitigating take by Level A harassment. Furthermore,
artificial lighting, while better for PSOs, brings hazards to migratory
birds.
Response: NMFS disagrees with the CBD's comment. The IHA does
consider and address conductor pipe installation activities during low-
visibility and nighttime conditions. If inclement weather conditions
(i.e., fog, rain, or rough Beaufort sea state) limit or impair PSO's
visibility of the water's surface to less than 30.5 m (100 ft) within
the action area, all noise-generating conductor pipe installation
activities must be stopped until visibility improves. To facilitate
visual monitoring during non-daylight hours, the exclusion zones must
be illuminated by lights to allow for more effective viewing of the
area by the PSO on-duty.
ExxonMobil is providing artificial lighting for conductor pipe
installation activities during nighttime and low visibility operations
at the +15 ft level of the Harmony Platform that will provide adequate
visibility to allow observation of the 3.5 m and 10 m exclusion zones
for pinnipeds and cetaceans, respectively, as well as the surrounding
areas. The lighting will only be on for those periods when conductor
pipes are being driven at night or during periods of low visibility
which typically occur for only a short period of time during the
activities using the impact hammer. The artificial lighting that will
be installed will have light shields attached to direct the light
downward toward the water. Note that the Harmony Platform has existing
lighting to allow for safe operations and to comply with regulations.
ExxonMobil will continue its current monitoring practices throughout
the planned conductor pipe installation activities, and will note any
increase in bird activity during nighttime operations.

Monitoring and Reporting

Comment 18: The Commission states that the accurate
characterization of the sizes of the buffer and exclusion zones is
critical for implementing mitigation measures and estimating the
numbers of animals taken. In the past, the Commission has recommended a
rapid turnaround of the in-situ sound source verification analysis to
ensure that buffer and exclusion zones are the appropriate size.
However, in at least one instance, rapid turnaround has resulted in
errors, as occurred with ION's measurements of source levels during its
2012 Arctic in-ice survey. In that case, the size of the exclusion zone
was decreased from that modeled based on erroneous field-report
results. The error was not discovered until the end of the field
season, when it was determined that the in-season adjustments resulted
in unauthorized Level A harassment takes of bowhead whales. Since the
purpose of sound source verification is to ensure protection of marine
mammals, one way to reduce risk to marine mammals would be to allow
only for expansion, but not contraction, of the buffer and/or exclusion
zones after in-situ adjustment in the size of the buffer and/or
exclusion zones if the size(s) of the estimated zones are determined to
be too small. The CCC also supports an adaptive approach to adjusting
the buffer and exclusion zones based on in-situ data collected during
the sound source verification. The process of adjusting the zones
should begin from a protective baseline.
Response: Monitoring will be performed during all impact hammer
pipe-driving operations. Hydrophones will be deployed prior to the
start of impact hammer pipe-driving the first pipe section. Data will
be collected and analyzed upon completion of the conductor pipe's last
pipe section. Monitoring equipment will be redeployed prior to
installation of the remaining five conductor pipes. Upon completion of
the first conductor pipe, acoustic data will be retrieved from the near
field (approximately 10 m) and far field (approximately 325 to 500 m)
recorders, analyzed, and compared to the predicted rms radii distances
for the buffer and exclusion zones. ExxonMobil will consult with NMFS
prior to proceeding with conductor pipe installation activities in the
event that acoustic field data indicate that predicted radii distances
for the buffer and exclusion zones need to adjusted (either expanded or
contracted). Distances will be recalculated using field data, and
monitoring equipment will be redeployed at the corrected distances
prior to installation of the remaining conductor pipes, following
authorization from NMFS. The planned extended down period (non-
hammering) between the completion of the first pipe installation and
the start of the second pipe installation will be used to determine the
actual size of buffer and exclusion zones (i.e., Level B and Level A
harassment zones) to ensure that the radii estimated from acoustic
modeling are not too small.
Comment 19: The CCC states that due to the uncertainties with
modeling, site specific, and/or seasonal oceanographic conditions, they
request being provided copies of the monitoring reports referenced in
the notice of the proposed IHA (79 FR 36743, June 30, 2014) for

[[Page 58923]]

ExxonMobil's conductor pipe installation activities. If monitoring
indicates impacts greater than anticipated, CCC intends to continue to
work with NMFS to assure the activity can be modified accordingly to
minimize effects on marine mammals.
Response: NMFS will provide copies of the in-water and in-air
monitoring and sound source verification report for ExxonMobil's
conductor pipe installation activities to the CCC when the document has
been completed (after the first conductor pipe has been installed and,
the in-situ measurements taken). NMFS will also provide the final 90-
day monitoring report required by the IHA to the CCC and make it
publicly available on our Web site at: https://www.nmfs.noaa.gov/pr/permits/incidental.htm#iha.

Acoustic Thresholds

Comment 20: CBD states that NMFS's current 160 dB threshold for
Level B harassment in the notice of the proposed IHA (79 FR 36743, June
30, 2014) does not reflect the best available science and is not
sufficiently conservative. CBD state that in particular, the 160 dB
threshold is non-conservative, because the scientific literature
establishes that behavioral disruption can occur at substantially lower
received levels for some species.
Response: NMFS's practice has been to apply the 160 dB received
level threshold for underwater impulse sound levels to determine
whether take by Level B harassment occurs. Specifically, NMFS derived
the 160 dB threshold data from mother-calf pairs of migrating gray
whales (Malme et al., 1983, 1984) and bowhead whales (Richardson et
al., 1985, 1986) responding to airgun operations. NMFS acknowledge
there is more recent information bearing on behavioral reactions to
sound sources such as pile-driving, seismic airguns, sonars,
electromechanical devices, etc., but those data only illustrate how
complex and context-dependent the relationship is between the various
sound sources, and do not, as a whole, invalidate the current
threshold. Accordingly, it is not a matter of merely replacing the
existing threshold with a new one. NMFS discussed the science on this
issue qualitatively in our analysis of potential effects to marine
mammals in the Federal Register notice of the proposed IHA (79 FR
36743, June 30, 2014). NMFS is currently developing revised acoustic
guidelines for assessing the effects of anthropogenic sound on marine
mammals. Until NMFS finalizes these guidelines (a process that includes
internal agency review, public notice and comment, and peer review),
NMFS will continue to rely on the existing criteria for Level A and
Level B harassment shown in Table 4 of the notice of the proposed IHA
(79 FR 36743, June 30, 2014).
As mentioned in the Federal Register notice of the proposed IHA (79
FR 36743, June 30, 2014), NMFS expects that the onset for behavioral
harassment is largely context dependent (e.g., behavioral state of the
animals, distance from the sound source, etc.) when evaluating
behavioral responses of marine mammals to acoustic sources. Although
using a uniform sound pressure level of 160 dB for the onset of
behavioral harassment for impulse noises may not capture all of the
nuances of different marine mammal reactions to sound, it is an
appropriate way to manage and regulate anthropogenic noise impacts on
marine mammals until NMFS finalizes its acoustic guidelines.
Comment 21: CBD states that NMFS's use of the 180 and 190 dB
thresholds for estimating Level A harassment and the likelihood of
temporary and/or permanent threshold shift do not consider the best
available science and is not sufficiently conservative. CBD cites
Kastak et al. (2008), Lucke et al. (2009), Wood et al. (2012) and
Kajawa and Liberman (2009).
Response: As explained in the notice of the proposed IHA (79 FR
36743, June 30, 2014), ExxonMobil will be required to establish a 180
and 190 dB re 1 [mu]Pa exclusion zone for marine mammals before the
conductor pipe installation activities begin. NMFS expects that the
required platform-based visual monitoring of the exclusion zones is
appropriate to implement mitigation measures to prevent Level A
harassment. If the PSOs observe marine mammals approaching the
exclusion zone, ExxonMobil must shut-down pipe driving to ensure that
the marine mammal does not approach the applicable exclusion radius.
The avoidance behaviors discussed in the notice of the proposed IHA (79
FR 36743, June 30, 2014) also supports our expectations that
individuals will avoid exposure at higher levels.
NMFS's current Level A thresholds, which identify levels above
which PTS could be incurred, were designed to be precautionary in that
they were based on levels were animals had incurred TTS. NMFS is
currently working on finalizing acoustic guidance that will identify
revised TTS and PTS thresholds that references the studies identified
by CBD. In order to ensure the best possible product, the process for
developing the revised thresholds includes both peer and public review
(both of which have already occurred) and NMFS will begin applying the
new thresholds once the peer and public input have been addressed and
the acoustic guidance is finalized.
Regarding the Lucke et al. (2009) study, the authors found a
threshold shift (TS) of a harbor porpoise after exposing it to airgun
noise (single pulse) with a received sound pressure level (SPL) at
200.2 dB (peak-to-peak) re 1 [mu]Pa, which corresponds to a sound
exposure level of 164.5 dB re 1 [mu]Pa\2\ s after integrating exposure.
NMFS currently uses the root-mean-square (rms) of received SPL at 180
dB and 190 dB re 1 [mu]Pa as the threshold above which permanent
threshold shift (PTS) could occur for cetaceans and pinnipeds,
respectively. Because the pipe-driving noise is a broadband impulse,
one cannot directly extrapolate the equivalent of rms SPL from the
reported peak-to-peak SPLs reported in Lucke et al. (2009). However,
applying a conservative conversion factor of 16 dB for broadband
signals from seismic surveys (Harris et al., 2001; McCauley et al.,
2000) to correct for the difference between peak-to-peak levels
reported in Lucke et al. (2009) and rms SPLs; the rms SPL for TTS would
be approximately 184 dB re 1 [mu]Pa, and the received levels associated
with PTS (Level A harassment) would be higher. This is still above the
current 180 dB rms re 1 [mu]Pa threshold for injury. Yet, NMFS
recognizes that the temporary threshold shift (TTS) of harbor porpoise
is lower than other cetacean species empirically tested (Finneran et
al., 2002; Finneran and Schlundt, 2010; Kastelein et al., 2012). NMFS
considered this information in the notice of the proposed IHA (79 FR
36743, June 30, 2014).
A Thompson et al. (1998) telemetry study on harbor (Phoca vitulina)
and grey seals (Halichoerus grypus) suggested that avoidance and other
behavioral reactions by individual seals to small airgun sources may at
times be strong, but short-lived. The researchers conducted 1-hour
controlled exposure experiments exposing individual seals fitted with
telemetry devices to small airguns with a reported source level of 215-
224 dB re 1 [mu]Pa (peak-to-peak) (Thompson et al., 1998; Gordon et
al., 2003). The researchers measured dive behavior, swim speed heart
rate and stomach temperature (indicator for feeding), but they did not
measure hearing threshold shift in the animals. The researchers
observed startle responses, decreases in heart rate, and temporary
cessation of feeding. In six out of eight trials, harbor seals
exhibited strong avoidance behaviors, and swam

[[Page 58924]]

rapidly away from the source (Thompson et al., 1998; Gordon et al.,
2003). One seal showed no detectable response to the airguns,
approaching within 300 m (984 ft) of the source (Gordon et al., 2003).
However, they note that the behavioral responses were short-lived and
the seals' behavior returned to normal after the trials (Thompson et
al., 1998; Gordon et al., 2003). The study does not discuss temporary
threshold shift or permanent threshold shift in harbor seals and the
estimated rms SPL for this survey is approximately 200 dB re 1 [mu]Pa,
well above NMFS's current 180 dB rms re 1 [mu]Pa threshold for injury
for cetaceans and NMFS' current 190 dB rms re 1 [mu]Pa threshold for
injury for pinnipeds (accounting for the fact that the rms sound
pressure level (in dB) is typically 16 dB less than the peak-to-peak
level).
In a study on the effect of non-impulsive sound sources on marine
mammal hearing, Kastak et al. (2008) exposed one harbor seal to an
underwater 4.1 kHz pure tone fatiguing stimulus with a maximum received
sound pressure of 184 dB re 1 [mu]Pa for 60 seconds (Kastak et al.,
2008; Finneran and Branstetter, 2013). A second 60-second exposure
resulted in an estimated threshold shift of greater than 50 dB at a
test frequency of 5.8 kHz (Kastak et al., 2008). The seal recovered at
a rate of -10 dB per log (min). However, 2 months post-exposure, the
researchers observed incomplete recovery from the initial threshold
shift resulting in an apparent permanent threshold shift of 7 to 10 dB
in the seal (Kastak et al., 2008). NMFS notes that pipe-driving using
an impact hammer sound is an impulsive source, and the context of
Kastak et al. (2008) study is related to the effect of non-impulsive
sounds on marine mammals.
NMFS also considered two other Kastak et al. (1999, 2005) studies.
Kastak et al. (1999) reported TTS of approximately 4-5 dB in three
species of pinnipeds (harbor seal, California sea lion, and northern
elephant seal) after underwater exposure for approximately 20 minutes
to sound with frequencies ranging from 100 to 2,000 Hz at received
levels 60 to 75 dB above hearing threshold. This approach allowed
similar effective exposure conditions to each of the subjects, but
resulted in variable absolute exposure values depending on subject and
test frequency. Recovery to near baseline levels was reported within 24
hours of sound exposure. Kastak et al. (2005) followed up on their
previous work, exposing the same test subjects to higher levels of
sound for longer durations. The animals were exposed to octave-band
sound for up to 50 minutes of net exposure. The study reported that the
harbor seal experienced TTS of 6 dB after a 25-minute exposure to 2.5
kHz of octave-band sound at 152 dB (183 dB SEL). The California sea
lion demonstrated onset of TTS after exposure to 174 dB (206 dB SEL).
NMFS acknowledges that PTS could occur if an animal experiences
repeated exposures to TTS levels. However, an animal would need to stay
very close to the sound source for an extended amount of time to incur
a serious degree of PTS, which in this case would be highly unlikely
due to the required mitigation measures in place to avoid Level A
harassment and the expectation that a mobile marine mammal would
generally avoid an area where received sound pulse levels exceed 160 dB
re 1 [mu]Pa (rms) (review in Richardson et al., 1995; Southall et al.,
2007).
NMFS also considered recent studies by Kujawa and Liberman (2009)
and Lin et al. (2011). These studies found that despite completely
reversible threshold shifts that leave cochlear sensory cells intact,
large threshold shifts (40 to 50 dB) could cause synaptic level changes
and delayed cochlear nerve degeneration in mice and guinea pigs,
respectively. NMFS notes that the high level of TTS that led to the
synaptic changes shown in these studies is in the range of the high
degree of TTS that Southall et al. (2007) used to calculate PTS levels.
It is not known whether smaller levels of TTS would lead to similar
changes. NMFS, however, acknowledges the complexity of noise exposure
on the nervous system, and will re-examine this issue as more data
become available.
In contrast, a recent study on bottlenose dolphins (Schlundt, et
al., 2013) measured hearing thresholds at multiple frequencies to
determine the amount of TTS induced before and after exposure to a
sequence of impulses produced by a seismic airgun. The airgun volume
and operating pressure varied from 40 to 150 in\3\ and 1,000 to 2,000
psi, respectively. After three years and 180 sessions, the authors
observed no significant TTS at any test frequency, for any combinations
of airgun volume, pressure, or proximity to the dolphin during
behavioral tests (Schlundt, et al., 2013). Schlundt et al. (2013)
suggest that the potential for airguns (or in this case pipe-driving
using an impact hammer) to cause hearing loss in dolphins is lower than
previously predicted, perhaps as a result of the low-frequency content
of airgun impulses compared to the high-frequency hearing ability of
dolphins. Although the sounds from pipe-driving using an impact hammer
are not equivalent to those produced by a seismic airgun, they are both
considered impulse sounds.
Comment 22: CBD states that NMFS must consider that even behavioral
disturbance can amount to Level A take if it interferes with essential
life functions.
Response: NMFS notes that Level B take has been defined previously
in this document and specifically relates to behavioral disturbance.
NMFS acknowledge that behavioral harassment in certain contexts, or
continued over long durations, may, in certain situations have impacts
on health and fitness of marine mammals. The discussion of whether
these more severse impacts on individuals (which could lead to
population-level impacts) occur as a result of any particular project
are included in the negligible impact analysis. They are also
considered qualitatively in the development of mitigation measures, via
consideration of biologically important areas in the analysis and for
time-area closures, or other important factors. Please see the response
to comment 21 for a discussion of studies addressing PTS (Level A
harassment).
Comment 23: CBD requested that NMFS use a behavioral threshold
below 160 dB for estimating take based on results reported in Bain and
Williams (2006), Clark and Gagnon (2006), MacLeod et al. (2006), Risch
et al. (2012), and DeRuiter et al. (2013).
Response: NMFS is constantly evaluating new science and how to best
incorporate it into our decisions. This process involves careful
consideration of new data and how it is best interpreted within the
context of a given management framework. Each of these articles
emphasizes the importance of context (e.g., behavioral state of the
animals, distance from the sound source, etc.) in evaluating behavioral
responses of marine mammals to acoustic sources.
These papers and the studies discussed in the notice of the
proposed IHA (79 FR 36743, June 30, 2014) note that there is
variability in the behavioral responses of marine mammals to noise
exposure. However, it is important to consider the context in
predicting and observing the level and type of behavioral response to
anthropogenic signals (Ellison et al., 2012). There are many studies
showing that marine mammals do not show behavioral responses when
exposed to multiple pulses at received levels at or above 160 dB re 1
[micro]Pa (e.g., Malme et al., 1983; Malme et al., 1984; Richardson et
al., 1986; Akamatsu et al., 1993; Madsen

[[Page 58925]]

and Mohl, 2000; Harris et al., 2001; Miller et al., 2005; and Weir,
2008). And other studies show that whales continue important behaviors
in the presence of seismic pulses (e.g., Richardson et al., 1986;
McDonald et al., 1995; Greene et al., 1999a, 1999b; Nieukirk et al.,
2004; Smultea et al., 2004; Holst et al., 2005, 2006; Dunn and
Hernandez, 2009).
In a passive acoustic research program that mapped the soundscape
in the North Atlantic, Clark and Gagnon (2006) reported that some fin
whales stopped singing for an extended period starting soon after the
onset of a seismic survey in the area. The study did not provide
information on received levels or distance from the sound source. The
authors could not determine whether or not the whales left the area
ensonified by the survey, but the evidence suggests that most if not
all singers remained in the area (Clark and Gagnon, 2006). Support for
this statement comes from the fact that when the survey stopped
temporarily, the whales resumed singing within a few hours and the
number of singers increased with time (Clark and Gagnon, 2006). Also,
they observed that one whale continued to sing while the seismic survey
was actively operating (Figure 4; Clark and Gagnon, 2006).
The authors conclude that there is not enough scientific knowledge
to adequately evaluate whether or not these effects on singing or
mating behaviors are significant or would alter survivorship or
reproductive success (Clark and Gagnon, 2006). Thus, to address CBD's
concerns related to the results of this action, it is important to note
that ExxonMobil's action area is well away from any known breeding/
calving grounds for low frequency cetaceans, thereby reducing further
the likelihood of causing an effect on marine mammals.
MacLeod et al. (2006) discussed the possible displacement of fin
and sei whales related to distribution patterns of the species during a
large-scale seismic survey offshore the west coast of Scotland in 1998.
The authors hypothesized about the relationship between the whale's
absence and the concurrent seismic activity, but could not rule out
other contributing factors (Macleod et al., 2006; Parsons et al.,
2009). NMFS would expect that marine mammals may briefly respond to
underwater sound produced by the pipe-driving activities by slightly
changing their behavior or relocating a short distance. Based on the
best available information, NMFS expects short-term disturbance
reactions that are confined to relatively small distances and durations
(Thompson et al., 1998; Thompson et al., 2013), with no long-term
effects on recruitment or survival.
Risch et al. (2012) documented reductions in humpback whale
(Megaptera novaeangliae) vocalizations in the Stellwagen Bank National
Marine Sanctuary concurrent with transmissions of the Ocean Acoustic
Waveguide Remote Sensing (OAWRS) low-frequency fish sensor system at
distances of 200 km (108 nmi) from the source. The recorded OAWRS
produced series of frequency modulated pulses and the signal received
levels ranged from 88 to 110 dB re 1 [mu]Pa (Risch et al., 2012). The
authors hypothesize that individuals did not leave the area but instead
ceased singing and noted that the duration and frequency range of the
OAWRS signals (a novel sound to the whales) were similar to those of
natural humpback whale song components used during mating (Risch et
al., 2012). Thus, the novelty of the sound to humpback whales in the
study area provided a compelling contextual probability for the
observed effects (Risch et al., 2012). However, the authors did not
state or imply that these changes had long-term effects on individual
animals or populations (Risch et al., 2012), nor did they necessarily
rise to the level of an MMPA take. Thus, to address CBD's concerns
related to the results of this study, NMFS again notes that the
ExxonMobil's action area is well away from any known breeding/calving
grounds for low frequency cetaceans, thereby reducing further the
likelihood of causing an effect on marine mammals.
With repeated exposure to sound, many marine mammals may habituate
to the sound at least partially (Richardson & Wursig, 1997). Bain and
Williams (2006) examined the effects of a large airgun array (maximum
total discharge volume of 1,100 in\3\) on six species in shallow waters
off British Columbia and Washington: harbor seal, California sea lion
(Zalophus californianus), Steller sea lion (Eumetopias jubatus), gray
whale (Eschrichtius robustus), Dall's porpoise (Phocoenoides dalli),
and the harbor porpoise. Harbor porpoises showed ``apparent avoidance
response'' at received levels less than 145 dB re 1 [mu]Pa at a
distance of greater than 70 km (37.8 nmi) from the seismic source (Bain
and Williams, 2006). However, the tendency for greater responsiveness
by harbor porpoise is consistent with their relative responsiveness to
boat traffic and some other acoustic sources (Richardson et al. 1995;
Southall et al., 2007). In contrast, the authors reported that gray
whales seemed to tolerate exposures to sound up to approximately 170 dB
re 1 [mu]Pa (Bain and Williams, 2006) and Dall's porpoises occupied and
tolerated areas receiving exposures of 170 to 180 dB re 1 [mu]Pa (Bain
and Williams, 2006; Parsons et al., 2009). The authors observed several
gray whales that moved away from the airguns toward deeper water where
sound levels were higher due to propagation effects resulting in higher
noise exposures (Bain and Williams, 2006). However, it is unclear
whether their movements reflected a response to the sounds (Bain and
Williams, 2006). Thus, the authors surmised that the gray whale data
(i.e., voluntarily moving to areas where they are exposed to higher
sound levels) are ambiguous at best because one expects the species to
be the most sensitive to the low-frequency sound emanating from the
airguns (Bain and Williams, 2006).
DeRuiter et al. (2013) recently observed that beaked whales
(considered a particularly sensitive species to sound) exposed to
playbacks (i.e., simulated) of U.S. tactical mid-frequency sonar from
89 to 127 dB re 1 [mu]Pa at close distances responded notably by
altering their dive patterns. In contrast, individuals showed no
behavioral responses when exposed to similar received levels from
actual U.S. tactical mid-frequency sonar operated at much further
distances (DeRuiter et al., 2013). As noted earlier, one must consider
the importance of context (for example, the distance of a sound source
from the animal) in predicting behavioral responses. Regarding the
public comments submitted by Clark et al. (2012) in reference to NMFS's
use of the current acoustic exposure criteria; please refer to our
earlier response to CBD.
None of these studies on the effects of airgun noise on marine
mammals point to any associated mortalities, strandings, or permanent
abandonment of habitat by marine mammals. Bain and Williams (2006)
specifically conclude that ``. . . although behavioral changes were
observed, the precautions utilized in the SHIPS survey did not result
in any detectable marine mammal mortalities during the survey, nor were
any reported subsequently by the regional marine mammal stranding
network . . .'' The ExxonMobil's 160-dB threshold radius will likely
not reach the threshold distances reported in these studies.
Currently NMFS is in the process of revising its behavioral noise
exposure criteria based on the best and most recent scientific
information. NMFS will use these criteria to develop methodologies to
predict behavioral responses of marine mammals exposed to sound
associated with conductor pipe

[[Page 58926]]

installation activities (primary source impact hammer operations).
Although using a uniform sound pressure level of 160-dB re 1 [mu]Pa for
the onset of behavioral harassment for impulse noises may not capture
all of the nuances of different marine mammal reactions to sound, it is
an appropriate way to manage and regulate anthropogenic noise impacts
on marine mammals until NMFS finalizes its acoustic guidelines.
Comment 24: The CCC states that it applies a more conservative
approach to permitting pile-driving in state waters and recommends
using the model-generated 160-dB threshold as the initial exclusion
zone that would trigger a shut-down of conductor pipe installation
activities using the impact hammer if marine mammals are sighted by
PSOs approaching or entering this area. The more protective 160 dB
exclusion zone generated by modeling could subsequently be reduced if
in-situ measurements taken during the sound source verification
indicate that this is warranted. If use of the model-generated 160 dB
threshold for this purpose was found to be infeasible, the CCC staff
would recommend an alternate strategy of imposing an additional
protective buffer to the model-generated 180 and 190 dB based exclusion
zones.
Response: NMFS expects that acoustic stimuli resulting from the
impact hammer pipe-driving associated with the conductor pipe
installation activities has the potential to result in Level B
harassment of marine mammals. NMFS disagrees with the CCC's
recommendation to use the model-generated 160 dB threshold for
underwater sounds as the initial exclusion zone that would trigger a
shut-down for all marine mammals. Current NMFS practice, regarding
exposure of marine mammals to high-level underwater sounds is that
cetaceans and pinnipeds exposed to impulsive sounds at or above 180 and
190 dB (rms), respectively, have the potential to be injured (i.e.,
Level A harassment). NMFS considers the potential for Level B
(behavioral) harassment to occur when marine mammals are exposed to
sounds below injury thresholds but at or above the 160 dB (rms)
threshold for impulse sounds (e.g., impact pile-driving) and the 120 dB
(rms) threshold for continuous noise (e.g., vibratory pile-driving). No
vibratory pile-driving is planned for ExxonMobil's planned activities
in the Santa Barbara Channel.
The CCC's recommendation to use the estimated 160 dB exclusion zone
as a trigger for shut-down is inconsistent with existing NMFS practice,
and would effectively expand the Level A harassment exclusion zone for
cetaceans and pinnipeds. It should be noted that a much larger
exclusion zone for triggering shut-downs of conductor pipe installation
activities has the potential to result in operational delays which
could extend impact hammer pipe-driving time and/or result of losing a
conductor pipe because successful completion of installation relies on
consistent movement of the steel pipe through the bed sediment.
NMFS also disagrees with the CCC's recommendation regarding the use
of a protective buffer to the model-generated 180 and 190 dB based
exclusion zones. Monitoring will be performed during all impact hammer
pipe-driving operations. Hydrophones will be deployed prior to the
start of impact hammer pipe-driving the first pipe section. Data will
be collected and analyzed upon completion of the conductor pipe's last
pipe section. Monitoring equipment will be redeployed prior to
installation of the remaining five conductor pipes. Upon completion of
the first conductor pipe, acoustic data will be retrieved from the near
field (approximately 10 m) and far field (approximately 325 to 500 m)
recorders, analyzed, and compared to the predicted rms radii distances
for the buffer and exclusion zones. ExxonMobil will consult with NMFS
prior to proceeding with conductor pipe installation activities in the
event that acoustic field data indicate that predicted radii distances
for the buffer and exclusion zones need to adjusted (either expanded or
contracted). Distances will be recalculated using field data, and
monitoring equipment will be redeployed at the corrected distances
prior to installation of the remaining conductor pipes, following
authorization from NMFS. The planned extended down period (non-
hammering) between the completion of the first pipe installation and
the start of the second pipe installation will be used to determine the
actual size of buffer and exclusion zones (i.e., Level B and Level A
harassment zones) to ensure that the radii estimated from acoustic
modeling are not determined to be too small.
NMFS and ExxonMobil acknowledges that in-situ measurements of the
sound may not agree with the modeled acoustic data due to uncertainties
and model limitations identified by the CCC; however, it is not
possible to improve model accuracy without obtaining data from the
field. For this reason, a sound source verification will be conducted
during the driving of the impact hammer for the first conductor pipe.
The data collected and analyzed will be used to establish more accurate
buffer and exclusion zones, and refine the acoustic model, if needed,
before installation of the second conductor pipe begins.
Finally, the CCC cites IHAs issued previously by NMFS as precedent
for its recommended approach to establishing exclusion zones using the
160 dB threshold as the trigger for implementing a shut-down procedure.
Based on the citation provided by CCC (e.g., Naval Base Kitsap wharfs/
piers, 2011 and 2014), it is not clear whether the CCC believes there
are additional examples of precedent or what specific action is
referred to for 2011 (no references are provided in the CCC's letter,
and NMFS issued two IHAs for construction activities at Naval Base
Kitsap in 2011). However, referring to the 2014 example, in which NMFS
issued an IHA to the Navy for take that could occur incidental to the
third year of work associated with construction of a wharf (79 FR
43429, July 25, 2014), the exclusion zone was in fact established on
the basis of in-situ sound source measurements, following initial
definition based on modeling results. This approach was identical to
that described by NMFS in our notice of the proposed IHA (79 FR 36743,
June 30, 2014), and the example does not provide supportive precedent
for the CCC's recommendation.

Effects Analyses

Comment 25: The CBD states that NMFS's evaluation in the notice of
the proposed IHA (79 FR 36743, June 30, 2014) regarding the impacts
from loss of prey on foraging are unknown; therefore, NMFS must get
such data and analyze it to make its negligible impact determination.
Response: NMFS disagrees with the CBD's comment. The anticipated
effects on marine mammal habitat, including effects on potential prey
and potential foraging habitat were described in the notice of the
proposed IHA (79 FR 36743, June 30, 2014). Secondary effects, such as
impacts to prey and habitat, are very important to NMFS's analysis and
are considered in both the negligible impact analysis as well as
qualitatively in the development of mitigation measures, via
consideration of biologically important areas in the analysis and for
time-area closures, or other important factors.

NEPA Concerns

Comment 26: The CBD states that NMFS must comply fully with the
National Environmental Policy Act (NEPA). The CBD states that NMFS
notes that it will complete an EA prior to its decision on the IHA.
Based on

[[Page 58927]]

multiple factors in NEPA's regulations, that the proposed activities do
constitute a significant impact, and NMFS should prepare a full EIS.
The purpose and need for the action is unclear and unnecessary. The IHA
application does not fully explain the need and purpose of the
additional conductor pipes. The notice of the proposed IHA (79 FR
36743, June 30, 2014) states that the conductors are ``to maintain
current production levels from the existing platform.'' This indicates
that there is no need for the proposed action because maintenance of
the current production levels should be able to be attained through the
status quo.
Response: In accordance with the National Environmental Policy Act
(NEPA; 42 U.S.C. 4321 et seq.), NMFS completed an EA titled,
``Environmental Assessment on the Issuance of an Incidental Harassment
Authorization to ExxonMobil Production Company to Take Marine Mammals
by Harassment Incidental to Conductor Pipe Installation Activities at
Harmony Platform in the Santa Barbara Channel Offshore of California.''
NMFS's EA includes all required components, including a brief
discussion of need for the proposed action, a listing of the
alternatives to the proposed action, a description of the affected
environment, a brief discussion of the environmental impacts of the
proposed action and alternatives, and sufficient evidence and analysis
for determining whether to prepare an EIS or a Finding of No
Significant Impact (FONSI).
NOAA Administrative Order (NAO) 216-6 contains criteria for
determining the significance of the impacts of a proposed action. In
addition, the Council on Environmental Quality (CEQ) regulations at 40
CFR 1508.27 state that the significance of an action should be analyzed
both in terms of ``context'' and ``intensity.'' NMFS evaluated the
significance of this action based on the NAO 216-6 criteria and CEQ's
context and intensity criteria. Based on this evaluation, NMFS
determined that issuance of this IHA to ExxonMobil would not
significantly impact the quality of the human environment and issued a
FONSI. Accordingly, preparation of an EIS is not necessary. NMFS's
determination and evaluation of the NAO 216-6 criteria and CEQ's
context and intensity criteria are contained within the FONSI issued
for this action, which is available on NMFS's Web site at: https://www.nmfs.noaa.gov/pr/permits/incidental/.
Comment 27: The CBD states NMFS must consider the additional
suggested mitigation measures as alternatives in its NEPA analysis. An
environmental review must ``inform decision-makers and the public of
the reasonable alternatives which would avoid or minimize adverse
impacts or enhance the quality of the human environment.'' NMFS must
``rigorously explore and objectively evaluate all reasonable
alternatives, and for alternatives which were eliminated from detailed
study, briefly discuss the reasons for their having been eliminated.''
In addition, an agency must discuss measures designed to mitigate its
action's impact on the environment. Accordingly, time-area closures,
larger exclusion zones, low-visibility limitations, and noise reducing
techniques should be considered in the range of alternatives.
Response: In accordance with the National Environmental Policy Act
(NEPA; 42 U.S.C. 4321 et seq.), NMFS completed an EA titled,
``Environmental Assessment on the Issuance of an Incidental Harassment
Authorization to ExxonMobil Production Company to Take Marine Mammals
by Harassment Incidental to Conductor Pipe Installation Activities at
Harmony Platform in the Santa Barbara Channel Offshore of California.''
The EA analyzes the impacts on the human environment of the issuance of
an IHA by NMFS to ExxonMobil for conductor pipe installation activities
at Harmony Platform in Santa Barbara Channel. It includes an evaluation
of two alternatives:
(1) Issuance of an IHA with mitigation measures, and
(2) A no action alternative (i.e., do not issue an IHA and do not
conduct the seismic survey).
The EA also included a section on alternatives that were considered
but eliminated from further consideration. NMFS considered whether
other alternatives could meet the purpose and need and support
ExxonMobil's conductor pipe installation activities. NMFS considered an
alternative with additional mitigation measures; including the specific
measures suggested by CBD, but eliminated that alternative from further
consideration because the additional mitigation measures were
considered not practicable or not likely to minimize adverse impacts.
NMFS also considered an alternative that would allow for the issuance
of an IHA with no required mitigation or monitoring but eliminated that
alternative from further consideration, as it would not be in
compliance with the MMPA and therefore would not meet the purpose and
need.
The EA will be available on the NMFS ITA Web site at: https://www.nmfs.noaa.gov/pr/permits/incidental/.
Comment 29: The CBD states that NMFS has a duty to consider the
indirect impacts of its action. Indirect effects ``are caused by the
action and are later in time or farther removed in distance, but are
still reasonably foreseeable.'' Although the purpose of the conductor
pipes is unclear, any changes in production, drilling, waste,
techniques, or lifetime of the oil and gas operations at Harmony
Platform must be fully disclosed and adequately evaluated. If, for
example, the conductor pipes will be used for or enable hydraulic
fracturing or other unconventional well stimulation techniques then the
environmental effects must evaluated.
Response: Changes to the production, drilling, waste, techniques,
or lifetime of the oil and gas operations at Harmony Platform are
regulated by the Bureau of Ocean Energy Management and the Bureau of
Safety and Environmental Enforcement. As stated in the notice of the
proposed IHA (79 FR 36743, June 30, 2014), ExxonMobil requested an IHA
from NMFS to take marine mammals, by harassment, incidental to
installing six conductor pipes at Harmony Platform. In accordance with
the National Environmental Policy Act (NEPA; 42 U.S.C. 4321 et seq.),
NMFS completed an EA to evaluate the environmental effects of
authorizing the take of marine mammals incidental to ExxonMobil's
activities. The EA considers the direct, indirect, and cumulative
impacts related to the issuance of an IHA authorizing the take of
marine mammals incidental ExxonMobil's activities.
NMFS notes that all produced fluids from ExxonMobil's offshore
Santa Ynez Production Unit are routed to the onshore treating
facilities located in Las Flores Canyon, where it is treated and re-
routed via pipeline, and discharged under an existing Environmental
Protection Agency National Pollutant Discharge Elimination System
(NPDES) permit. ExxonMobil has not used hydraulic fracturing on any of
the wells on the three platforms in the Santa Ynez Production Unit
located offshore of California. ExxonMobil has not and does not plan to
use hydraulic fracturing or other unconventional well techniques in its
offshore operations.
Comment 29: The CBD states that NMFS must also look at the
cumulative effects (past, present, and reasonably foreseeable future
actions) of the action. For example, the Santa Barbara Channel is a
busy shipping lane which means that the cumulative effects of noise

[[Page 58928]]

pollution from ship traffic and ship strikes must be evaluated. Whales
fleeing pile-driving activities may be forced into shipping lanes to
continue their foraging. Additionally, hydraulic fracturing activities
from offshore oil and gas platforms in the area threaten endangered
species and marine mammals in numerous ways--from oil spills and vessel
strikes to air and water pollution. More than half of the platforms in
federal waters discharge their wastewater, which can include toxic
fracking chemicals, into the ocean. Harmony Platform alone is permitted
to discharge over 33,000 barrels of wastewater into the ocean each
year.
Response: The NMFS EA analyzes the effects of NMFS's issuance of an
IHA with mitigation and monitoring measures for the conductor pipe
installation activities in light of other past, present, and reasonably
foreseeable actions in the area including (1) other impact pipe-driving
activities; (2) research activities; (3) military testing and training
activities; (4) oil and gas activities; (5) vessel traffic, noise, and
collisions; (6) commercial and recreational fishing; and (7) climate
change. The EA concludes that the impacts of the issuance of an IHA for
ExxonMobil's proposed conductor pipe installation activities in the
Santa Barbara Channel offshore of California are expected to be no more
than minor and short-term with no potential to contribute to
cumulatively significant impacts.
NMFS notes that Harmony Platform is located on the coastal side of
the shipping lane in Santa Barbara Channel, while foraging areas are
concentrated on the seaward side of the shipping lane; thus the whales
would not be forced into the area busy with vessel traffic to forage.
The shipping channel is located 12 to 14 km (6.5 to 7.6 nmi) from the
Harmony Platform, and underwater sounds are within normal ambient
ranges at the platform (e.g., 120 dB). As stated previously in this
document, ExxonMobil does not perform hydraulic fracturing at Harmony
Platform or elsewhere offshore of California. All produced water,
including any fluids that are produced through the wells, are treated
at the Las Flores Canyon facility and discharged as permitted under the
Clean Water Act.

General Concerns

Comment 30: Numerous private citizens, as supporters of SierraRise
and Sierra Club, and the CBD, oppose the issuance of the IHA to
ExxonMobil. They call on the government to stop destructive actions in
the Santa Barbara Channel that lead to impairment, injury, and death of
marine mammals. ExxonMobil's conductor pipe installation activities
could lead to the death of many whales, otters, and more animals that
are already threatened by toxic fracking fluids that have been dumped
into their water. The commenters state that marine mammals deserve a
safe, healthy ocean environment to live in, a healthy ocean is more
important than more climate-killing offshore drilling.
Response: As described in detail in the Federal Register notice for
the proposed IHA (79 FR 36743, June 30, 2014), as well as in this
document, NMFS anticipates only behavioral disturbance to occur during
the conductor pipe installation activities. NMFS has determined that
ExxonMobil's conductor pipe installation activities will not cause
injury, serious injury, or mortality to marine mammals managed under
NMFS's jurisdiction, and not takes by injury, serious injury, or
mortality are authorized. Further, ExxonMobil is required to implement
a number of mitigation and monitoring measures during the impact hammer
pipe-driving activities, which are described below in the
``Mitigation'' and ``Monitoring and Reporting'' sections. NMFS has
determined that the required mitigation measures provide the means of
effecting the least practicable impact on marine mammal species or
stocks and their habitat, paying particular attention to rookeries,
mating grounds, and areas of similar significance. The sea otter is
managed by the U.S. Fish and Wildlife Service.
Comment 31: The CBD states that NMFS should consider the
environmental impacts of the activity on nearby marine protected areas
(MPAs), reserves, and the Channel Islands National Marine Sanctuary
that are located in the vicinity of the conductor pipe installation
activities.
Response: NMFS has considered environmental impacts of the
conductor pipe installation activities on nearby MPAs as well as the
Channel Islands National Marine Sanctuary. Individual mainland MPAs in
southern California include: Point Conception State Marine Reserve
(SMR), Kashtayit State Marine Conservation Area (SMCA), Naples SMCA,
Campus Point SMCA, Goleta Slough SMCA, Point Dume SMCA, Point Dume SMR,
Point Vicente SMCA, Abalone Cove SMCA, Bolsa Chica Basin SMCA, Upper
Newport Bay SMCA, Crystal Cove SMCA, Laguna Beach SMR, Laguna Beach
SMCA, Dana Point SMCA, Batiquitos Lagoon SMCA, Swami's SMCA, San Elijo
Lagoon SMCA, San Diego-Scripps Coastal SMCA, Matlahuayl SMR, South La
Jolla SMR, South La Jolla SMCA, Famosa Slough SMCA, Cabrillow SMR, and
Tijuana River Mouth SMCA. Individual island MPAs include: Richardson
Rock SMR and Federal MR, San Miguel Island Special Closure, Harris
Point SMR and Federal MR, Judith Rock SMR, Carrington Point SMR, Skunk
Point SMR, South Point SMR and Federal MR, Painted Cave SMCA, Gull
Island SMR and Federal MR, Anacapa Island Special Closure, Anacapa
Island SMR and Federal MR, Anacapa Island SMCA and Federal MCA,
Footprint SMR and Federal MR, Begg Rock SMR, Santa Barbara Island MR
and Federal MR, Arrow Point to Lion Head Point SMCA, Blue Cavern SMCA,
Bird Rock SMCA, Long Point SMR, Casino Point SMCA, Lover's Cover SMCA,
Farnsworth Onshore SMCA, Farnsworth Offshore SMCA, and Cat Harbor SMCA.
The closest MPAs, which are Naples SMCA and Point Conception SMR, are
over 18.5 km (10 nmi) east-southeast and 27.8 km (15 nmi) west-
northwest at its closest boundary to Harmony Platform, respectively.
Sound levels generated during the planned conductor pipe installation
activities will not have significant consequences on MPAs because all
MPAs are a minimum of 18.5 km from the Harmony Platform and the
platform is not in shallow water depths.
The Channel Islands National Marine Sanctuary is about 25.9 km (14
nmi) southwest at its closest boundary to Harmony Platform. NMFS has
contacted Channel Islands National Marine Sanctuary regarding
ExxonMobil's planned conductor pipe installation activities and the
associated issuance of an IHA. NMFS has determined that a consultation
under the National Marine Sanctuary Act is not necessary as the planned
action is not anticipated to have impacts on sanctuary resources.
Comment 32: The CBD states that noise from conductor pipe
installation activities can impact EFH and NMFS must fully comply with
its statutory obligation to consult on the impact of federal activities
on essential fish habitat (EFH) under the Magnuson-Stevens Fishery
Conservation and Management Act (MSA). The EFH consultation should
include an evaluation of the effects of the action on EFH, proposed
mitigation, and make conservation recommendations.
Response: NMFS disagrees with the commenter's assessment. NMFS's
issuance of an IHA and the mitigation and monitoring measures required
by the IHA would not affect ocean and coastal habitat or EFH.
Therefore, NMFS, Office of Protected Resources,

[[Page 58929]]

Permits and Conservation Division determined that an EFH consultation
is not required.
Comment 33: The CBD states that NMFS must comply fully with the
Endangered Species Act (ESA) and develop a robust Biological Opinion
based on the best available science. The proposed conductor pipe
installation activities may have harmful impacts on ESA-listed marine
mammals (including North Pacific right, humpback, sei, fin, blue, and
sperm whales, as well as southern sea otters and Guadalupe fur seals),
which must be fully and accurately vetted through the consultation
process. Accordingly, NMFS must complete consultation and obtain any
take authorization before authorizing the proposed activities. They
further urge NMFS to establish more stringent mitigation measures to
avoid adverse impacts to ESA-listed species.
Response: Section 7(a)(2) of the ESA requires that each federal
agency insure that any action authorized, funded, or carried out by
such agency is not likely to jeopardize the continued existence of any
endangered or threatened species or result in the destruction or
adverse modification of critical habitat of such species. Of the
species of marine mammals that may occur in the action area, several
are listed as endangered under the ESA, including the North Pacific
right, Western North Pacific gray, humpback, sei, fin, blue, and sperm
whales as well as the Guadalupe fur seal. Although critical habitat is
designated for the North Pacific right whale, no critical habitat for
North Pacific right whales occurs in the action area. The North Pacific
right whale critical habitat in the Pacific Ocean can be found online
at: https://www.nmfs.noaa.gov/pr/pdfs/criticalhabitat/northpacificrightwhale.pdf.
NMFS's Office of Protected Resources, Permits and Conservation
Division, initiated and engaged in formal consultation under section 7
of the ESA with NMFS's West Coast Regional Office, Protected Resources
Division, on the issuance of an IHA under section 101(a)(5)(D) of the
MMPA for this activity. NMFS's West Coast Regional Office, Protected
Resources Division issued a Biological Opinion addressing the effects
of the proposed actions on threatened and endangered species as well as
designated critical habitat in September 2014. The Biological Opinion
concluded that NMFS's issuance of an IHA to ExxonMobil is not likely to
jeopardize the existence of any threatened and endangered species and
would have no effect on critical habitat. NMFS's West Coast Regional
Office, Protected Resources Division, relied on the best scientific and
commercial data available in conducting its analysis.
NMFS's Office of Protected Resources, Permits and Conservation
Division also considered the conservation status and habitat of ESA-
listed marine mammals. Included in the IHA are special procedures for
situations or species of concern (see ``Mitigation'' section below). If
a North Pacific right whale is visually sighted during the conductor
pipe installation activities, the pipe-driving activities must be shut-
down regardless of the distance of the animal(s) to the sound source.
The pipe-driving will not resume firing until 30 minutes after the last
documented whale visual sighting. Concentrations of humpback, sei, fin,
blue, and/or sperm whales will be avoided if possible (i.e., exposing
concentrations of animals to 160 dB), and the activities will be shut-
down if necessary. For purposes of the conductor pipe installation
activities, a concentration or group of whales will consist of three or
more individuals visually sighted that do not appear to be traveling
(e.g., feeding, socializing, etc.). NMFS's West Coast Regional Office,
Protected Resources Division, issued an Incidental Take Statement (ITS)
incorporating the requirements of the IHA as Terms and Conditions of
the ITS. Compliance with the ITS is likewise a mandatory requirement of
the IHA. NMFS's Office of Protected Resources, Permits and Conservation
Division has determined that the mitigation measures required by the
IHA provide the means of effecting the least practicable impact on
species or stocks and their habitat, including ESA-listed species.
Comment 34: The CBD states that NMFS must comply fully with the
Coastal Zone Management Act (CZMA). The CZMA requires that applicants
for federal permits to conduct an activity affecting a natural resource
of the coastal zone of a state ``shall provide in the application to
the licensing or permitting agency a certification that the proposed
activity complies with the enforceable policies of the state's approved
program and that such activity will be conducted in a manner consistent
with the program.'' CBD states that marine species that will be
affected by the project are ``natural resources'' protected by
California's coastal management program, and that California should be
given the opportunity to review the IHA for consistency with their
coastal management programs.
Response: As the lead federal agency for the IHA, NMFS considered
whether the action would have effects on the coastal resources of any
state along the U.S. West Coast. As concluded in the notice of the
proposed IHA (79 FR 36743, June 30, 2014), any potential impacts from
the conductor pipe installation activities would mainly be to marine
species in close proximity to the Harmony Platform and would be of a
short duration and temporary in nature. The Harmony Platform is located
at 34[deg] 22'35.906'' North and 120[deg]10'04.48'' West, which is
located approximately 10 km (5.4 nmi) off the coast of California, in
federal waters. NMFS discussed issuance of the IHA and ExxonMobil's
planned conductor pipe installation activities with the California
Coastal Commission. Therefore, NMFS has concluded that we have met all
of the responsibilities under the CZMA.
Comment 35: The CBD is concerned that ExxonMobil is not in full
compliance with the Outer Continental Shelf Lands Act (OCSLA). The CBD
states that NMFS provided no support for its statement that the
proposed conductor pipe installation activities are considered in the
existing Development and Production Plan.
Response: The OCSLA is administered by the Department of the
Interior. NMFS does not have the regulatory authority to permit
ExxonMobil's activities under the OCSLA. As stated in the notice of the
proposed IHA (79 FR 36743, June 30, 2014), ExxonMobil requested an IHA
from NMFS to take marine mammals, by harassment, incidental to
installing six conductor pipes at Harmony Platform in the Santa Barbara
Channel. Consistent with its regulatory authority under the MMPA, NMFS
determined that authorizing the take of small numbers of marine mammals
by Level B harassment incidental to ExxonMobil's activities would have
a negligible impact on marine mammals species or stocks and would not
have an unmitigable adverse impact on the availability of species or
stocks for taking for subsistence uses, and prescribed the permissible
methods of taking by harassment pursuant such activity and other means
of effecting the least practicable impact on species or stocks and
their habitat.

Description of the Marine Mammals in the Area of the Specified Activity

The marine mammals that generally occur in the planned action area
belong to four taxonomic groups: mysticetes (baleen whales),
odontocetes (toothed whales), pinnipeds (seals and sea lions), and
fissipeds (sea otters). The marine mammal species that potentially
occur within the Pacific Ocean in proximity to the action area in the
Santa Barbara

[[Page 58930]]

Channel off the coast of California (ranging from Point Conception and
south, including the entire Southern California Bight) include 31
species of cetaceans (whales, dolphins, and porpoises) and 6 species of
pinnipeds. The southern sea otter (Enhydra lutris nereis) is listed as
threatened under the ESA and is managed by the U.S. Fish and Wildlife
Service and is not considered further in this IHA notice.
Marine mammal species listed as threatened or endangered under the
U.S. Endangered Species Act of 1973 that could potentially occur in the
action area (ESA; 16 U.S.C. 1531 et seq.), include the North Pacific
right (Eubalaena japonica), Western North Pacific population gray
(Eschrichtius robustus), humpback (Megaptera novaeangliae), sei
(Balaenoptera borealis), fin (Balaenoptera physalus), blue
(Balaenoptera musculus), and sperm (Physeter macrocephalus) whale as
well as the Guadalupe fur seal (Arctocephalus townsendi). Of those
threatened and endangered species, the humpback, sei, fin, blue, and
sperm whale are likely to be encountered in the action area.
Cetaceans occur throughout the Santa Barbara Channel action area,
including nearby the Harmony Platform, from the surf zone to open ocean
environments beyond the Channel Islands. Distribution is influenced by
a number of factors, but primary among these are patterns of major
ocean currents, bottom relief, and sea surface temperature. These
physical oceanographic conditions affect prey abundance, which may
attract marine mammals during periods of high productivity, and vice
versa. Water movement is near continuous, varying seasonally, and is
generally greatest from late spring to early fall in response to
varying wind stress. This phenomenon is much greater in the western
Santa Barbara Channel. This near continuous movement of water from the
ocean bottom to the surface creates a nutrient-rich, highly productive
environment for marine mammal prey (Jefferson et al., 2008). Most of
the large cetaceans are migratory, but many small cetaceans do not
undergo extensive migrations. Instead, they undergo local or regional
dispersal, on a seasonal basis or in response to food availability.
Population centers may shift on spatial scales exceeding 100 km (54
nmi) over small time scales (days or weeks) (Dailey and Bonnell, 1993).
Systematic surveys (1991 to 1993, 1996, 2001, 2005) in the southern
California region have been carried out via aircraft (Carretta and
Forney, 1993) and vessel (Ferguson and Barlow, 2001; Barlow, 2003) by
NMFS. In addition, a vessel survey in the U.S. Exclusive Economic Zone
(EEZ), and out to 556 km (300.2 nmi) offshore of California, Oregon,
and Washington, was conducted in the summer and fall of 2005 by NMFS
(Forney, 2007). Many other regional surveys have also been conducted
(Carretta, 2003). Becker (2007) analyzed data from vessel surveys
conducted since 1986, and compiled marine mammal densities. There are
31 cetacean and 6 pinniped species with ranges that are known to occur
in the Eastern North Pacific Ocean waters of the project area. These
include the North Pacific right whale, dwarf sperm whale (Kogia sima),
harbor porpoise (Phocoena phocoena), Steller sea lion (Eumatopias
jubatus), and Guadalupe fur seal. However, these species are extremely
rare, found in the Channel Islands, or are primarily found north or
south of the Santa Barbara Channel, and are unlikely to be found in the
action area. The harbor porpoise occurs north of Point Conception,
California. Guadalupe fur seals are most common at Guadalupe Island,
Mexico, which is their primary breeding ground (Melin and Delong,
1999). Although adult and juvenile males have been observed at San
Miguel Island, California, since the mid-1960's, and in the late 1990's
a pup was born on the islands (Melin and Delong, 1999), more recent
sightings are extremely rare. These species are not considered further
in this document. Table 4 (below) presents information on the
occurrence, abundance, distribution, population status, and
conservation status of the species of marine mammals that may occur in
the project area during September to December 2014.

Table 4--The Habitat, Occurrence, Range, Regional Abundance, and Conservation Status of Marine Mammals That May Occur in or Near the Pipe Installation
Project Area Off the Coast of California in the Pacific Ocean
[See text and Tables 3-1 in ExxonMobil's IHA application for further details]
--------------------------------------------------------------------------------------------------------------------------------------------------------
Best population
Species Habitat Occurrence Range estimate (Minimum) ESA \2\ MMPA \3\
\1\
--------------------------------------------------------------------------------------------------------------------------------------------------------
Mysticetes
--------------------------------------------------------------------------------------------------------------------------------------------------------
North Pacific right whale Coastal and Rare.............. North Pacific NA (26)--Eastern EN................ D
(Eubalaena japonica). pelagic. Ocean between 20 North Pacific
to 60[deg] North. stock.
Gray whale (Eschrichtius Coastal and shelf. Transient during North Pacific 19,126 (18,107)-- DL--Eastern North NC--Eastern North
robustus). seasonal Ocean, Gulf of Eastern North Pacific stock EN-- Pacific stock D--
migrations. California to Pacific stock 155 Western North Western North
Arctic--Eastern (142)--Western Pacific Pacific
North Pacific North Pacific population. population
stock. population.
Humpback whale (Megaptera Pelagic, nearshore Seasonal, Cosmopolitan...... 1,918 (1,855)-- EN................ D
novaeangliae). waters, and banks. sightings near California/Oregon/
northern Channel Washington (CA/OR/
Islands. WA) stock.
Minke whale (Balaenoptera Pelagic and Less common in Tropics and sub- 478 (202)--CA/OR/ NL................ NC
acutorostrata). coastal. summer, small tropics to ice WA stock.
number around edges.
northern Channel
Islands.
Bryde's whale (Balaenoptera Pelagic and Rare, infrequent Tropical and sub- NA--No stock for NL................ NC
edeni). coastal. summer off tropical zones CA/OR/WA.
California. between 40[deg]
North and 40[deg]
South.

[[Page 58931]]

Sei whale (Balaenoptera Primarily Rare, infrequent Tropical to polar 126 (83)--Eastern EN................ D
borealis). offshore, pelagic. summer off zones, favor mid- North Pacific
California. latitude stock.
temperate areas.
Fin whale (Balaenoptera Continental slope, Year-round Tropical, 3,051 (2,598)--CA/ EN................ D
physalus). pelagic. presence. temperate, and OR/WA stock.
polar zones of
all oceans.
Blue whale (Balaenoptera Pelagic, shelf, Seasonal, arrive Tropical waters to 1,647 (1,551)-- EN................ D
musculus). coastal. April to May, pack ice edges. Eastern North
common late- Pacific stock.
summer to fall
off Southern
California.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Odontocetes
--------------------------------------------------------------------------------------------------------------------------------------------------------
Sperm whale (Physeter Pelagic, deep sea. Common year-round, Tropical waters to 971 (751)--CA/OR/ EN................ D
macrocephalus). more likely in pack ice edges. WA stock.
waters >1,000 m.
Pygmy sperm whale (Kogia Pelagic, slope.... Seaward of 500 to Tropical to warm 579 (271)--CA/OR/ NL................ NC
breviceps). 1,000 m, Limited temperate zones WA stock.
sightings in (temperate
Southern preference).
California Bight.
Dwarf sperm whale (Kogia sima).. Deep waters off Rare.............. Tropical to warm NA--CA/OR/WA stock NL................ NC
the shelf. temperate zones
(warmer
preference).
Baird's beaked whale (Berardius Pelagic........... Primarily along North Pacific 847 (466)--CA/OR/ NL................ NC
bairdii). continental slope Ocean and WA stock.
late spring to adjacent seas.
early fall.
Cuvier's beaked whale (Ziphius Pelagic........... Possible year- Cosmopolitan...... 6,590 (4,481)--CA/ NL................ NC
cavirostris). round occurrence. OR/WA stock.
Blainville's beaked whale Pelagic........... Rare, continental Temperate and 694 (389)-- NL................ NC
(Mesoplodon densirostris). slope region, tropical waters Mesoplodon spp.
generally seaward worldwide. CA/OR/WA stock.
of 500 to 1,000 m
depth.
Perrin's beaked whale Pelagic........... Rare, continental North Pacific 694 (389)-- NL................ NC
(Mesoplodon perrini). slope region, Ocean. Mesoplodon spp.
generally seaward CA/OR/WA stock.
of 500 to 1,000 m
depth.
Lesser beaked whale (Mesoplodon Pelagic........... Rare, continental Temperate and 694 (389)-- NL................ NC
peruvianis). slope region, tropical waters Mesoplodon spp.
generally seaward Eastern Pacific CA/OR/WA stock.
of 500 to 1,000 m Ocean.
depth.
Stejneger's beaked whale Pelagic........... Rare, continental North Pacific 694 (389)-- NL................ NC
(Mesoplodon stejnegeri). slope region, Ocean. Mesoplodon spp.
generally seaward CA/OR/WA stock.
of 500 to 1,000 m
depth.
Ginkgo-toothed beaked whale Pelagic........... Rare, continental Temperate and 694 (389)-- NL................ NC
(Mesoplodon ginkgodens). slope region, tropical waters Mesoplodon spp.
generally seaward Indo-Pacific CA/OR/WA stock.
of 500 to 1,000 m Ocean.
depth.
Hubbs' beaked (Mesoplodon Pelagic........... Rare, continental North Pacific 694 (389)-- NL................ NC
carlhubbsi). slope region, Ocean. Mesoplodon spp.
generally seaward CA/OR/WA stock.
of 500 to 1,000 m
depth.
Killer whale (Orcinus orca)..... Pelagic, shelf, Varies on inter- Cosmopolitan...... 240 (162)--Eastern NL................ NC
coastal, pack ice. annual basis, North Pacific
likely in winter Offshore stock
(January to 346 (346)--
February). Eastern North
Pacific Transient
stock 354 (354)--
West Coast
Transient stock.
False killer whale (Pseudorca Pelagic........... Rare.............. Tropical to warm NA--No stock for NL................ NC
crassidens). temperate zones. CA/OR/WA.
Short-finned pilot whale Pelagic, shelf, Uncommon, more Warm temperate to 760 (465)--CA/OR/ NL................ NC
(Globicephala macrorhynchus). coastal. common before tropical waters, WA stock.
1982. ~50[deg] North to
40[deg] South.

[[Page 58932]]

Bottlenose dolphin (Tursiops Offshore, inshore, Offshore stock-- Tropical and 1,006 (684)--CA/OR/ NL................ NC
truncatus). coastal, Year-round temperate waters WA Offshore stock
estuaries. presence Coastal between 45[deg] 323 (290)--
stock--Limited, North and South. California
small population Coastal stock.
within 1 km of
shore.
Striped dolphin (Stenella Off continental Occasional visitor Tropical to 10,908 (8,231)--CA/ NL................ NC
coeruleoalba). shelf. temperate waters, OR/WA stock.
50[deg] North to
40[deg] South.
Short-beaked common dolphin Shelf, pelagic, Common, more Tropical to 411,211 (343,990)-- NL................ NC
(Delphinus delphis). seamounts. abundant in temperate waters CA/OR/WA stock.
summer. of Atlantic and
Pacific Ocean.
Long-beaked common dolphin Inshore........... Common, more Nearshore and 107,016 (76,224)-- NL................ NC
(Delphinus capensis). inshore tropical waters. California stock.
distribution,
year-round
presence.
Pacific white-sided dolphin Offshore, slope... Common, year- Temperate waters 26,930 (21,406)-- NL................ NC
(Lagenorhynchus obliquidens). round, more of North Pacific CA/OR/WA,
abundant November Ocean. Northern and
to April. Southern stock.
Northern right whale dolphin Pelagic........... Common, more North Pacific 8,334 (6,019)--CA/ NL................ NC
(Lissodelphis borealis). abundant November Ocean, 30 to OR/WA stock.
to April. 50[deg] North.
Risso's dolphin (Grampus Deep water, Common, present in Continental slope 6,272 (4,913)--CA/ NL................ NC
griseus). seamounts. summer, more and outer shelf OR/WA stock.
abundant November of tropical to
to April. temperate waters.
Dall's porpoise (Phocoenoides Shelf, slope, Common, more North Pacific 42,000 (32,106)-- NL................ NC
dalli). offshore. abundant November Ocean, 30 to CA/OR/WA stock.
to April. 62[deg] North.
Harbor porpoise (Phocoena Coastal and inland AK to Point Shallow temperate NA................ NL................ NC
phocoena). waters. Conception, CA. to sub-polar
waters of
Northern
Hemisphere.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Pinnipeds
--------------------------------------------------------------------------------------------------------------------------------------------------------
California sea lion (Zalophus Coastal, shelf.... Common, Channel Eastern North 296,750 (153,337)-- NL................ NC
californianus). Island breeding Pacific Ocean-- U.S. stock.
sites in summer. Alaska to Mexico.
Steller sea lion (Eumetopias Coastal, shelf.... Rare.............. North Pacific 49,685 (45,916)-- EN--Western stock D
jubatus). Ocean--Central Western stock DL--Eastern stock.
California to 58,334 to 72,223
Korea. (52,847)--Eastern
stock.
Pacific harbor seal (Phoca Coastal........... Common, haul-outs Coastal temperate 30,196 (26,667)-- NL................ NC
vitulina richardii). and rookeries in to polar regions California stock.
Channel Islands, in Northern
bulk of stock Hemisphere.
north of Point
Conception.
Northern elephant seal (Mirounga Coastal, pelagic Common, haul-outs Eastern and 124,000 (74,913)-- NL................ NC
angustirostris). when not and rookeries in Central North California
migrating. Channel Islands, Pacific Ocean-- breeding stock.
December to March Alaska to Mexico.
and April to
August, spend 8
to 10 months at
sea.
Northern fur seal (Callorhinus Pelagic, offshore. Common, small North Pacific 12,844 (6,722)-- NL................ NC
ursinus). population breeds Ocean--Mexico to California stock.
on San Miguel Japan.
Island May to
October.
Guadalupe fur seal Coastal, shelf.... Rare, observed in California to Baja 7,408 (3,028)-- T................. D
(Arctocephalus townsendi). Channel Islands. California, Mexico to
Mexico. California stock.
--------------------------------------------------------------------------------------------------------------------------------------------------------

[[Page 58933]]

Fissipeds
--------------------------------------------------------------------------------------------------------------------------------------------------------
Southern sea otter (Enhydra Coastal........... Mainland coastline North Pacific Rim-- 2,826 (2,723)-- T................. D
lutris nereis). from San Mateo Japan to Mexico. California stock.
County to Santa
Barbara County,
CA San Nicolas
Island.
--------------------------------------------------------------------------------------------------------------------------------------------------------
NA = Not available or not assessed.
\1\ NMFS Marine Mammal Stock Assessment Reports.
\2\ U.S. Endangered Species Act: EN = Endangered, T = Threatened, DL = Delisted, and NL = Not listed.
\3\ U.S. Marine Mammal Protection Act: D = Depleted, S = Strategic, and NC = Not Classified.

Further detailed information regarding the biology, distribution,
seasonality, life history, and occurrence of these marine mammal
species in the planned project area can be found in sections 3 and 4 of
ExxonMobil's IHA application. NMFS has reviewed these data and
determined them to be the best available scientific information for the
purposes of the IHA.

Potential Effects of the Specified Activity on Marine Mammals

This section includes a summary and discussion of the ways that the
types of stressors associated with the specified activity (e.g., impact
hammer pipe-driving) have been observed to impact marine mammals. This
discussion may also include reactions that we consider to rise to the
level of a take and those that we do not consider to revise to the
level of take (for example, with acoustics), we may include a
discussion of studies that showed animals not reacting at all to sound
or exhibiting barely measureable avoidance). This section is intended
as a background of potential effects and does not consider either the
specific manner in which this activity will be carried out or the
mitigation that will be implemented, and how either of those will shape
the anticipated impacts from this specific activity. The ``Estimated
Take by Incidental Harassment'' section later in this document will
include a quantitative analysis of the number of individuals that are
expected to be taken by this activity. The ``Negligible Impact
Analysis'' section will include the analysis of how this specific
activity will impact marine mammals and will consider the content of
this section, the ``Estimated Take by Incidental Harassment'' section,
the ``Mitigation'' section, and the ``Anticipated Effects on Marine
Mammal Habitat'' section to draw conclusions regarding the likely
impacts of this activity on the reproductive success or survivorship of
individuals and from that on the affected marine mammal populations or
stocks.
When considering the influence of various kinds of sound on the
marine environment, it is necessary to understand that different kinds
of marine life are sensitive to different frequencies of sound. Based
on available behavioral data, audiograms have been derived using
auditory evoked potentials, anatomical modeling, and other data,
Southall et al. (2007) designate ``functional hearing groups'' for
marine mammals and estimate 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 (13 species of mysticetes):
functional hearing is estimated to occur between approximately 7 Hz and
30 kHz;
Mid-frequency cetaceans (32 species of dolphins, six
species of larger toothed whales, and 19 species of beaked and
bottlenose whales): functional hearing is estimated to occur between
approximately 150 Hz and 160 kHz;
High-frequency cetaceans (eight species of true porpoises,
six species of river dolphins, Kogia spp., the franciscana (Pontoporia
blainvillei), and four species of cephalorhynchids): functional hearing
is estimated to occur between approximately 200 Hz and 180 kHz; and
Phocid pinnipeds in water: functional hearing is estimated
to occur between approximately 75 Hz and 100 kHz;
Otariid pinnipeds in water: functional hearing is
estimated to occur between approximately 100 Hz and 40 kHz.
As mentioned previously in this document, 32 marine mammal species
managed under NMFS jurisdiction (28 cetacean and 4 pinniped species)
are likely to occur in the action area. Of the 28 cetacean species
likely to occur in ExxonMobil's action area, 7 are classified as low-
frequency cetaceans (i.e., gray, humpback, minke, Bryde's, sei, fin,
and blue whale), 19 are classified as mid-frequency cetaceans (i.e.,
sperm, Baird's beaked, Cuvier's beaked, Blainville's beaked, Perrin's
beaked, Lesser beaked, Stejneger's beaked, Ginkgo-toothed beaked,
Hubb's beaked, killer, false killer, and short-finned pilot whale, as
well as bottlenose, striped, short-beaked common, long-beaked common,
Pacific white-sided, northern right whale, and Risso's dolphin), 2 are
classified as high-frequency cetaceans (i.e., pygmy sperm whale and
Dall's porpoise), 2 are classified as phocids (i.e., harbor and
northern elephant seal), and 2 are classified as otariid pinnipeds
(i.e., California sea lion and northern fur seal) (Southall et al.,
2007). A species' functional hearing group is a consideration when we
analyze the effects of exposure to sound on marine mammals.
Current NMFS practice, regarding exposure of marine mammals to
high-level underwater sounds is that cetaceans and pinnipeds exposed to
impulsive sounds at or above 180 and 190 dB (rms), respectively, have
the potential to be injured (i.e., Level A harassment). NMFS considers
the potential for Level B (behavioral) harassment to occur when marine
mammals are exposed to sounds below injury thresholds but at or above
the 160 dB (rms) threshold for impulse sounds

[[Page 58934]]

(e.g., impact pile-driving) and the 120 dB (rms) threshold for
continuous noise (e.g., vibratory pile-driving). No vibratory pile-
driving is planned for ExxonMobil's planned activities in the Santa
Barbara Channel. Current NMFS practice, regarding exposure of marine
mammals to high-level in-air sounds, as a threshold for potential Level
B harassment, is at or above 90 dB re 20 [micro]Pa for harbor seals and
at or above 100 dB re 20 [micro]Pa for all other pinniped species
(Lawson et al., 2002; Southall et al., 2007). NMFS has not established
a threshold for Level A harassment for marine mammals exposed to in-air
noise; however, Southall et al. (2007) recommends 149 dB re 20
[micro]Pa (peak) (flat) as the potential threshold for injury from in-
air noise for all pinnipeds.
Acoustic stimuli generated by the conductor pipe installation
activities, which introduce sound into the marine environment and in-
air, may have the potential to cause Level B harassment of marine
mammals in the action area. The effects of sounds from impact hammer
pile-driving activities might include one or more of the following:
tolerance, masking of natural sounds, behavioral disturbance, temporary
or permanent hearing impairment, or non-auditory physical or
physiological effects (Richardson et al., 1995; Gordon et al., 2004;
Nowacek et al., 2007; Southall et al., 2007). Permanent hearing
impairment, in the unlikely event that it occurred, will constitute
injury, but temporary threshold shift (TTS) is not an injury (Southall
et al., 2007). Although the possibility cannot be entirely excluded, it
is unlikely that the planned project will result in any cases of
temporary or permanent hearing impairment, or any significant non-
auditory physical or physiological effects. Based on the available data
and studies described here, some behavioral disturbance is expected.
The notice of the proposed IHA (79 FR 36743, June 30, 2014)
included a discussion of the effects of impact hammer pile-driving on
mysticetes, odontocetes, and pinnipeds including tolerance, masking,
behavioral disturbance, hearing impairment, other non-auditory physical
effects, and airborne sound effects. NMFS refers readers to that
document, ExxonMobil's IHA application and addendum and NMFS's EA for
additional information on the behavioral reactions (or lack thereof) by
all types of marine mammals to pile-driving activities.

Anticipated Effects on Marine Mammal Habitat, Fish, and Invertebrates

NMFS included a detailed discussion of the potential effects of
this action on marine mammal habitat, including anticipated effects on
potential prey and anticipated effects on potential foraging habitat in
the notice of the proposed IHA (79 FR 36743, June 30, 2014). The
conductor pipe installation activities will not result in any permanent
impact on habitats used by the marine mammals in the action area,
including the food sources they use (i.e., fish and invertebrates), and
there will be not physical damage to any habitat. While NMFS
anticipates that the specified activity may result in marine mammals
avoiding certain areas due to temporary ensonification, this impact to
habitat is temporary and inconsequential, which was considered in
further detail in the notice of the proposed IHA (79 FR 36743, June 30,
2014), as behavioral modification. The main impact associated with the
activity will be temporarily elevated noise levels and the associated
direct effects on marine mammals.

Mitigation

In order to issue an Incidental Take Authorization (ITA) under
section 101(a)(5)(D) of the MMPA, NMFS must set forth the permissible
methods of taking pursuant to such activity, and other means of
effecting the least practicable impact on such species or stock and its
habitat, paying particular attention to rookeries, mating grounds, and
areas of similar significance, and the availability of such species or
stock for taking for certain subsistence uses (where relevant).
ExxonMobil incorporated a suite of appropriate mitigation measures
into its project description (see Section 11 of the IHA application).
NMFS re-evaluated these mitigation measures after receiving public
comments on the notice of the proposed IHA.
To reduce the potential for disturbance from acoustic stimuli
associated with the proposed activities, ExxonMobil and/or its
designees will implement the following mitigation measures for marine
mammals:
(1) Buffer and exclusion zones around the sound source;
(2) Hours of operation;
(3) Shut-down procedures;
(4) Ramp-up procedures; and
Special procedures for situations or species of concern.
Exclusion Zones--ExxonMobil uses radii to designate exclusion and
buffer zones and to estimate take for marine mammals. Table 5 (see
below) shows the distances at which one will expect marine mammal
exposures to three received sound levels (160, 180, and 190 dB) from
the impact hammer. The 180 and 190 dB level shut-down criteria are
applicable to cetaceans and pinnipeds, respectively, as specified by
NMFS (2000). ExxonMobil used these levels to establish the exclusion
and buffer zones.

Table 5--Modeled Maximum Distances To Which In-Water Sound Levels >=190, 180 and 160 dB re 1 [mu]Pa (rms) and In-Air Sound Levels =90 (For
Harbor Seals) and 100 dB re 20 [mu]Pa (rms) (For All Other Pinnipeds) Could Be Received During the Impact Hammer Pile-Driving Activities (Based on
Maximum Hammer Energy of 90 kJ) in the Santa Barbara Channel Off the Coast of California
--------------------------------------------------------------------------------------------------------------------------------------------------------
Predicted RMS radii distances (m) for in-water Modeled RMS radii distances (m)
Water depth pile-driving for in-air pile-driving
Source (m) ------------------------------------------------------------------------------------
160 dB 180 dB 90 dB 190 dB 100 dB
--------------------------------------------------------------------------------------------------------------------------------------------------------
90 kJ Impact Hammer Pile-Driver................... 366 325 10 3.5 123 (403.5 ft) 41 (134.5 ft)
(1,066.3 ft) (32.8 ft) (11.5 ft)
--------------------------------------------------------------------------------------------------------------------------------------------------------

Based on the modeling, exclusion zones (for triggering a shut-down)
for Level A harassment will be established for cetaceans and pinnipeds
at 3.5 m (11.5 ft) and 10 m (32.8 ft) from the conductor pipe sound
source, respectively. These shut-down zones will be monitored by a
dedicated PSO. If the PSO detects a marine mammal(s) within or about to
enter the appropriate exclusion zone, the pile-driving activities will
be shut-down immediately. If marine mammals are present within the
shut-down zone before impact pile-driving activities begin, start of
operations will be delayed until the exclusion zones are clear for at
least 30 minutes. If marine mammals

[[Page 58935]]

appear in the shut-down zone during pile-driving activities, the PSO
will instruct the hammer operator to halt all operations in a safe, but
immediate manner. Pile-driving activities will only resume once the
exclusion zone has been cleared for at least 30 minutes. In the
unlikely event that the marine mammal enters the exclusion zone during
pile-driving activities, the exposure and behaviors will be documented
and reported by the PSO and NMFS will be contacted within 24 hours. A
non-PSO safety spotter will also be assigned to the lower deck
observation area. All personnel operating at the lower observation
levels will be required to wear appropriate personal protective
equipment.
Hours of Operation--The planned activities will be conducted on a
continual 24-hour basis; therefore, some of the 2.5 to 3.3 hours of
active impact pile-driving periods will be expected to occur during
non-daylight hours. To facilitate visual monitoring during non-daylight
hours, the exclusion zones will be illuminated to allow more effective
viewing by the PSO. Lighting will not be expected to attract marine
mammals. The areas where the exclusion zones occur fall within the
jacket structure of the platform, and therefore could be easily
illuminated by lights and monitored during non-daylight hours. For the
buffer zone, which will extend out to 325 m (1,066.3 ft) from the
conductor pipe, PSOs will be stationed on an upper deck of the Harmony
Platform to monitor for marine mammals during the pile-driving
activities. During non-daylight hours, PSOs will utilize night-vision
devices and other appropriate equipment to monitor marine mammals. If
nighttime visual aids are insufficient, ExxonMobil plans to use daytime
visual counts of marine mammals as an estimate of the number of marine
mammals present during non-daylight hours (within a 24-hour period),
noting that diurnal activities for most marine mammals are expected to
vary somewhat.
Shut-down Procedures--ExxonMobil will shut-down the operating
hammer if a marine mammal is detected outside the exclusion zone, and
the sound source will be shut-down before the animal is within the
exclusion zone. Likewise, if a marine mammal is already within the
exclusion zone when first detected, the sound source will be shut-down
immediately.
Following a shut-down, ExxonMobil will not resume pile-driving
activities until the marine mammal has cleared the exclusion zone.
ExxonMobil will consider the animal to have cleared the exclusion zone
if:
A PSO has visually observed the animal leave the exclusion
zone, or
A PSO has not sighted the animal within the exclusion zone
for 15 minutes for species with shorter dive durations (i.e., small
odontocetes and pinnipeds), or 30 minutes for species with longer dive
durations (i.e., mysticetes and large odontocetes, including sperm,
pygmy and dwarf sperm, killer, and beaked whales).
All visual monitoring will be conducted by qualified PSOs. Visual
monitoring will be conducted continuously during active pile-driving
activities. PSOs will not have any tasks other than visual monitoring
and will conduct monitoring from the best vantage point(s) practicable
(e.g., on the Harmony Platform or other suitable location) that
provides 360[deg] visibility of the Level A harassment exclusion zones
and Level B harassment buffer zone, as far as possible. The PSO will be
in radio communication with the hammer operator during pile-driving
activities, and will call for a shut-down in the event a pinniped or
cetacean appears to be headed toward its respective exclusion zone for
cetaceans and pinnipeds.
Ramp-up Procedures--Ramp-up (sometimes referred to as a ``soft-
start'') of the impact hammer provides a gradual increase in sound
levels until the full sound level is achieved. The purpose of a ramp-up
is to ``warn'' marine mammals in the vicinity of the impact hammer and
to provide the time for them to leave the area avoiding any potential
injury or impairment of their hearing abilities. A ramp-up consists of
an initial set of three strikes from the impact hammer at 40% energy,
followed by a 30-second waiting period, then two subsequent three
strike sets.
The buffer zone will be monitored by PSOs beginning 30 minutes
before pile-driving activities, during pile-driving, and for 30 minutes
after pile-driving stops. During ramp-up, the PSOs will monitor the
exclusion zone, and if marine mammals are sighted, a shut-down will be
implemented.
If the complete exclusion zone has not been visible for at least 30
minutes prior to the start of operations in either daylight or
nighttime, ExxonMobil will not commence the ramp-up. ExxonMobil will
not initiate a ramp-up of the impact hammer if a marine mammal is
sighted within or near the applicable exclusion zones during the day or
close to the Harmony Platform at night.
Special Procedures for Situations of Species of Concern--It is
unlikely that a North Pacific right whale will be encountered during
the conductor pipe installation activities, but if so, the pipe-driving
activities will be shut-down immediately if one is visually sighted at
any distance from the Harmony Platform because of its rarity and
conservation status. The pipe-driving activities shall not resume (with
ramp-up) until 30 minutes after the last documented North Pacific right
whale visual sighting. Concentrations of humpback, sei, fin, blue and/
or sperm whales shall be avoided if possible (i.e., exposing
concentrations of animals to 160 dB), and the sound source shall be
shut-down if necessary. For purposes of this planned conductor pipe
installation activities, a concentration or group of whales will
consist of three or more individuals visually sighted that do not
appear to be traveling (e.g., feeding, socializing, etc.).
Oil Spill Plan--ExxonMobil has developed an Oil Spill Response Plan
and it is on file with BOEM.

Mitigation Conclusions

NMFS has carefully evaluated the applicant's mitigation measures
and has considered a range of other measures in the context of ensuring
that NMFS prescribes the means of effecting the least practicable
impact on the affected marine mammal species and stocks and their
habitat. NMFS's evaluation of potential measures included consideration
of the following factors in relation to one another:
(1) The manner in which, and the degree to which, the successful
implementation of the measure is expected to minimize adverse impacts
to marine mammals;
(2) The proven or likely efficacy of the specific measure to
minimize adverse impacts as planned; and
(3) The practicability of the measure for applicant implementation,
including consideration of personnel safety, practicality of
implementation, and impact on the effectiveness of the activity.
Any mitigation measure(s) prescribed by NMFS should be able to
accomplish, have a reasonable likelihood of accomplishing (based on
current science), or contribute to the accomplishment of one or more of
the general goals listed below:
(1) Avoidance or minimization of injury or death of marine mammals
wherever possible (goals 2, 3, and 4 may contribute to this goal).
(2) A reduction in the numbers of marine mammals (total number or
number at biologically important time or location) exposed to received
levels of hammer pile-driving, or other activities expected to result
in the take of marine mammals (this goal may

[[Page 58936]]

contribute to 1, above, or to reducing harassment takes only).
(3) A reduction in the number of times (total number or number at
biologically important time or location) individuals will be exposed to
received levels of hammer pile-driving, or other activities expected to
result in the take of marine mammals (this goal may contribute to 1,
above, or to reducing harassment takes only).
(4) A reduction in the intensity of exposures (either total number
or number at biologically important time or location) to received
levels of hammer pile-driving, or other activities expected to result
in the take of marine mammals (this goal may contribute to a, above, or
to reducing the severity of harassment takes only).
(5) Avoidance of minimization of adverse effects to marine mammal
habitat, paying special attention to the food base, activities that
block or limit passage to or from biologically important areas,
permanent destruction of habitat, or temporary destruction/disturbance
of habitat during a biologically important time.
(6) For monitoring directly related to mitigation--an increase in
the probability of detecting marine mammals, thus allowing for more
effective implementation of the mitigation.
Based on NMFS's evaluation of the applicant's measures, as well as
other measures considered by NMFS or recommended by the public, NMFS
has determined that the mitigation measures provide the means of
effecting the least practicable impact on marine mammal species or
stocks and their habitat, paying particular attention to rookeries,
mating grounds, and areas of similar significance.

Monitoring and Reporting

In order to issue an ITA for an activity, section 101(a)(5)(D) of
the MMPA states that NMFS must 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 will 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 action area. ExxonMobil
submitted a marine mammal monitoring plan as part of the IHA
application. It can be found in Section 13 of the IHA application. The
plan may be modified or supplemented based on comments or new
information received from the public during the public comment period.
Monitoring measures prescribed by NMFS should accomplish one or
more of the following general goals:
(1) An increase in the probability of detecting marine mammals,
both within the mitigation zone (thus allowing for more effective
implementation of the mitigation) and in general to generate more data
to contribute to the analyses mentioned below;
(2) An increase in our understanding of how many marine mammals are
likely to be exposed to levels of sound from impact hammer pile-driving
activities that we associate with specific adverse effects, such as
behavioral harassment, TTS or PTS;
(3) An increase in our understanding of how marine mammals respond
to stimuli expected to result in take and how anticipated adverse
effects on individuals (in different ways and to varying degrees) may
impact the population, species, or stock (specifically through effects
on annual rates of recruitment or survival) through any of the
following methods:
Behavioral observations in the presence of stimuli
compared to observations in the absence of stimuli (need to be able to
accurately predict received level, distance from source, and other
pertinent information);
Physiological measurements in the presence of stimuli
compared to observations in the absence of stimuli (need to be able to
accurately predict receive level, distance from the source, and other
pertinent information);
Distribution and/or abundance comparisons in times or
areas with concentrated stimuli versus times or areas without stimuli;
(4) An increased knowledge of the affected species; and
(5) An increase in our understanding of the effectiveness of
certain mitigation and monitoring measures.

Monitoring

ExxonMobil will conduct to sponsor marine mammal monitoring during
the conductor pipe installation activities, in order to implement the
mitigation measures that require real-time monitoring, and to satisfy
the anticipated monitoring requirements of the IHA. ExxonMobil's
``Monitoring Plan'' is described below this section. ExxonMobil
understand that this monitoring plan will be subject to review by NMFS
and that refinements may be required. Two main types of monitoring will
be performed for this planned project: (1) In-situ measurement of sound
pressure levels; and (2) visual observations of the number and type of
marine mammals that enter sound exposure zones. In-situ acoustic data
will be used to validate model predictions of sound pressure levels
near and with distance from the conductor pipe sound source, including
the predicted maximum distances for the buffer and exclusion zones. If
measured results differ from modeled results, measured data will be
used to revise buffer and exclusion zone boundaries to reflect actual
conditions during planned project activities. Data from visual
monitoring will be used to validate take estimate calculations.

Acoustic Monitoring

Acoustic monitoring using hydrophones and microphones will be
conducted to obtain and validate modeled in-water and in-air sound
levels during the pipe-driving activities. Each hydrophone (in-water)
and microphone (in-air) will be calibrated following the manufacturer's
recommendations prior to the start of the planned project and checked
for accuracy and precision at the end of the data collection for each
conductor pipe or as practical during conductor pipe installation
activities. Environmental data will be collected to supplement the
acoustic monitoring and include: wind speed and direction, air
temperature, humidity, near-surface water temperature, weather
conditions, and other appropriate factors that could contribute to
influencing either in-air or in-water sound transmission levels. Prior
to deploying monitoring equipment, the acoustics specialist will be
provided with the hammer model and size, hammer energy settings, and
projected blows per minute for the conductor pipe segments requiring
hammer pipe-driving. Background in-air and in-water sound levels will
be measured at Harmony Platform in the absence of pipe-driving
activities to obtain an ambient noise level, and recorded over a
frequency range of 10 Hz to 20 kHz. Ambient noise level measurements
will be conducted before, during, and after the project. The measured
in-air and in-water sound data will be used to recalibrate and refine
the sound propagation model used to determine the buffer and exclusion
zones. Also, sound pressure levels associated with ramp-up techniques
will be measured.
In-Water Monitoring--Acoustic monitoring will be performed at a
minimum of two fixed stations located at 14 to 30 m (45.9 to 98.4 ft)
and approximately 325 to 500 m (+/-33 m 10%, 1,066.3 to 1,640.4 ft)
depending on the conductor pipe sound source location to the monitoring
location.

[[Page 58937]]

These distances represent the 180 dB and 160 dB (rms) modeled sound
levels. The following general approach will be used to measure in-water
sound levels:
Acoustic monitoring will be conducted over the entire
conductor pipe installation period for each conductor pipe, starting
approximately 1 hour prior to conductor pipe installation through 1
hour after impact hammering has stopped. Pre- and post-hammer conductor
pipe installation data will be used to determine ambient/background
noise levels.
A stationary hydrophone system with the ability to measure
and record sound pressure levels will be deployed at a minimum of two
monitoring locations (stations). SPLs will be recorded in voltage,
converted to microPascals ([micro]Pa), and post-processed to decibels
(dB [re 1 [micro]Pa]). For the first conductor pipe installation,
hydrophones are placed at 14 to 30 m (+/-1 m) and at 325 to 500 (+/-33
m) depending on the conductor pipe sound source location to the
monitoring location at depths ranging from 10 to 30 m (32.8 to 98.4 ft)
below the water surface to avoid potential inferences for surface water
energy, and to target the depth range of maximum occurrence of marine
mammals most likely in the area during the operations. The equipment
will obtain data for the most likely depth range of marine mammal
occurrence. Horizontal displacement of +/-10% may be expected for
instrument movement due to the water depth and forces from tides,
currents, and storms. Additional hydrophone mooring systems may be
deployed at additional distances and/or depths. Following each
successive conductor pipe installation, the water depth and
geographical orientation of the hydrophone may be changed to validate
modeled SPLs at varying water depths and direction.
At a minimum, the following sound data will be analyzed
(post-processed) from recorded sound levels: Absolute peak overpressure
and under pressure levels for each conductor pipe; average, minimum,
and maximum sound pressure levels (rms), integrated from 3 Hz to 20
kHz; average duration of each hammer strike (blow), and total number of
strikes per continuous impact hammer conductor pipe installation period
for each conductor.
In the event that field measurements indicate different sound
pressure levels (rms) values than those predicted by modeling for
either the maximum distances of the buffer or exclusion zones from the
conductor sound source, corresponding boundaries for the buffer and
appropriate exclusion zones will be increased/decreased accordingly,
following NMFS notification, concurrence, and authorization.
In-Air Monitoring--Reference measurements will be made at
approximately 10 to 20 m (32.8 to 65.6 ft) from the initial hammer
strike position using a stationary microphone. The microphone will be
placed as far away from other large sound sources as practical. The in-
air buffer zone predicted for pinnipeds (non-harbor seal, 100 dB re 20
[micro]Pa) was estimated at 41 m (134.5 ft) from the hammer impact
point on the conductor pipe. In-air sound levels will be recorded at
several points around the base of the Harmony Platform at sea level to
validate modeled sound levels. Distances closer to the sound source may
be monitored for model validation purposes, but only if safety issues
are not introduced. Recorded data will be recorded as dB (re 20
[micro]Pa, A-weighted and unweighted) for comparison to in-air noise
thresholds for Level B harassment for pinnipeds.
Sound Source Verification--At the initiation of conductor pipe
installation activities using the impact hammer (i.e., the installation
of the first pipe), direct measurements will be taken in the near and
far field of the received levels of underwater and in-air sound versus
distance and direction from the sound source using calibrated
hydrophones. The acoustic data from the sound source verification will
be analyzed as quickly as reasonably practicable in the field and used
to verify and adjust (based on the predicted distances) the buffer and
exclusion zones distances. The field report will be made available to
NMFS for review and approval and PSOs after completing the measurements
and before beginning the installation of the remaining conductor pipes.

Platform-Based Visual Monitoring

ExxonMobil's PSOs will be based aboard the Harmony Platform and
will watch for marine mammals near the platform during conductor pipe
installation activities during daytime and nighttime pipe-driving
activities. Visual monitoring for marine mammals will be performed at a
minimum during periods of active hammer pipe-driving throughout the
planned project following general procedures in Baker et al. (2013).
Monitoring by PSOs will begin at least 30 minutes before the start of
impact hammer pipe-driving, continue through an estimated 2.5 to 3.3
hours of pipe-driving, and conclude 30 minutes after pipe-driving stops
(up to 4.3 hours of monitoring per a period of pipe-driving). Five to 7
periods of impact hammer pipe-driving will be required for each
conductor pipe. When feasible, PSOs will conduct observations during
periods when the impact hammer pipe-driving is not operating for
comparison of sighting rates and behavior with and without operations
and between pipe-driving periods. In addition to monitoring during
pipe-driving activities, baseline monitoring of marine mammals will be
performed up to one week before and one week after conductor pipe
installation, as well as selected periods in between impact hammer
pipe-driving activities.
The exclusion zone will be monitored to prevent injury to marine
mammal species. Based on PSO observations, the impact hammer pipe-
driving will be shut-down when marine mammals are observed within or
about to enter the designated exclusion zone. The exclusion zone is a
region in which a possibility exists of adverse effects on animal
hearing or physical effects. A comprehensive monitoring plan will be
developed to ensure compliance with the IHA for this project.
Methods--There will be a team of 3 PSOs based aboard Harmony
Platform conducting monitoring during active hammer pipe-driving
periods. Visual observations will take place during active hammering
periods which includes both daylight and nighttime operations. This
monitoring will occur for approximately 4.3 hours (3.3 hour monitoring
plus 0.5 hour pre- and post-hammering) during a single hammering phase
followed by approximately 6.3 hours of off-duty rest. A total of 5 to 7
observation periods corresponding to the driving of the pipe segments
will be anticipated for each of the six conductors. It is possible that
an impact hammer pipe-driving session will take less than 3.3 hours and
that the ``rest interval'' for the visual monitors separating driving
segments will be less than 6.3 hours. If driving and rest intervals are
reduced and additional segments are added (e.g., seven instead of
five), two alternating teams of three PSOs may be required. At the
conclusion of impact hammer pipe-driving activities for a single
conductor pipe, PSOs may be transferred to shore to await the next
active pipe-driving phase.
PSOs will be placed at the best practicable vantage point(s) (e.g.,
lower platform level, upper platform level) to monitor the applicable
buffer and exclusion zones for marine mammals. The PSOs will have
authority to implement shut-down/delay ramp-up procedures, if
applicable, by calling the hammer operator for a shut-down via radio
communication. For the buffer zone, two PSOs will be stationed on an

[[Page 58938]]

upper platform deck where they have a clear view of the monitoring
area. They will be approximately 180 degrees apart and each will
monitor approximately one-half of the corresponding buffer zone and
beyond with binoculars and other appropriate equipment. For exclusion
zone area, one PSO will concurrently monitor the applicable radii for
pinnipeds and cetaceans, respectively, from a lower level observation
post that provides a clear view of the sea surface around the actively
driven conductor pipe. The lower observation area will be illuminated
during nighttime observations. Visual aids may be used but will not be
required, providing the PSO has a clear view of the sea surface with
the naked eye. A non-PSO safety spotter will also be assigned to the
lower deck observation area. The safety spotter will be available to
deter errant California sea lions using NMFS-recommended methods (see
below) (NMFS, 2008).
All personnel operating on the Harmony Platform will be required to
receive required training and wear appropriate personal protective
equipment. Personal protective equipment is specific to the task,
location, and environmental conditions (e.g., weather, operations
risks). It includes items such as floatation vests, hard hats, steel-
toed shoes, gloves, fire-resistant clothing, gear, eye protection, and
other protective equipment. Details on specific personal protective
equipment items required for PSO and acoustic monitoring will be
determined via the regular work risk assessment process, and will be
presented in the associated monitoring plans for the project.
Equipment for monitoring will include hearing protection from where
observations are made from high noise areas of the platform, marine
radios with headsets, time keeping device (e.g., watch or cell phone),
day and night range finding binoculars (7 x 50 or greater), notebooks
with standardized recording forms, species identification guides, and a
project-specific monitoring plan approved by NMFS (to be submitted
separately).
PSO Qualifications--Monitoring will be conducted by qualified PSOs
defined in Baker et al. (2013) and approved by NMFS. PSOs dedicated to
the planned project will have no other activity-related tasks.

PSO Data and Documentation

PSOs will record data to estimate the numbers of marine mammals
exposed to various received sound levels and to document apparent
disturbance reactions or lack thereof. Data will be used to estimate
numbers of animals potentially ``taken'' by harassment (as defined in
the MMPA). They will also provide information needed to order a shut-
down of the impact hammer when a marine mammal is within or near the
exclusion zone. Visual observations will also be made during pipe-
driving activities as well as daytime periods from the Harmony Platform
when the regular operations will be underway without pipe-driving
activities to collect baseline biological data.
When a sighting is made, the following information about the
sighting will be recorded:
1. Species, group size, age/size/sex categories (if determinable),
behavior when first sighted and after initial sighting, heading (if
consistent), bearing and distance from platform, sighting cue, apparent
reaction to the sound source (e.g., none, avoidance, approach,
paralleling, etc., and including responses to ramp-up), speed of
travel, and duration of presence.
2. Date, time, location, heading, speed, activity of the conductor
pipe installation activities, weather conditions, Beaufort sea state
and wind force, visibility, and sun glare.
The data listed under (2) will also be recorded at the start and
end of each observation watch, and during a watch whenever there is a
change in one or more of the variables.
All observations, as well as information regarding ramp-ups or
shut-downs will be recorded in a standardized format.
Results from the platform-based visual observations will provide
the following information:
1. The basis for real-time mitigation (impact hammer shut-down).
2. Information needed to estimate the number of marine mammals
potentially taken by harassment, which must be reported to NMFS.
3. Data on the occurrence, distribution, and activities of marine
mammals in the area where the conductor pipe installation activities
are conducted.
4. Information to compare the distance and distribution of marine
mammals relative to the source platform at times with and without pipe-
driving activities.
5. Data on the behavior and movement patterns of marine mammals
seen at times with and without pipe-driving activities.

Reporting

ExxonMobil will submit a comprehensive report to NMFS within 90
days after the end of the conductor pipe installation activities and
the expiration of the IHA (if issued). The report would describe the
pipe-driving activities that were conducted and sightings of marine
mammals near the operations. The report submitted to NMFS will provide
full documentation of methods, results, and interpretation pertaining
to all monitoring. The 90-day report will summarize the dates and
location of impact hammer pipe-driving activities and all marine mammal
sightings (i.e., dates, times, locations, activities, and associated
seismic survey activities). The report will minimally include:
Summaries of monitoring effort--total hours, total
distances, and distribution of marine mammals through the activity
period accounting for Beaufort sea state and other factors affecting
visibility and detectability of marine mammals;
Analyses of the effects of various factors influencing
detectability of marine mammals including Beaufort sea state, number of
PSOs, and fog/glare;
Species composition, occurrence, and distribution of
marine mammals sightings including date, water depth, numbers, age/
size/gender, and group sizes; and analyses of the effects of
activities;
Sighting rates of marine mammals during periods with and
without impact hammer pipe-driving activities (and other variables that
could affect detectability);
Initial sighting distances versus operational activity
state;
Closest point of approach versus operational activity
state;
Observed behaviors and types of movements versus
operational activity state;
Numbers of sightings/individuals seen versus operational
activity state; and
Distribution around the platform versus operational
activity state.

The report will also include estimates of the number and nature of
exposures that could result in ``takes'' of marine mammals by
harassment or in other ways (based on presence in the buffer and/or
exclusion zones). After the report is considered final, it will be
publicly available on the NMFS Web site at: https://www.nmfs.noaa.gov/pr/permits/incidental/.

Reporting Prohibited Take--In the unanticipated event that the
specified activity clearly causes the take of a marine mammal in a
manner prohibited by this IHA, such as an injury (Level A harassment),
serious injury, or mortality (e.g., ship-strike, gear interaction, and/
or entanglement), ExxonMobil will

[[Page 58939]]

immediately cease the specified activities and immediately report the
incident to the Chief of the Permits and Conservation Division, Office
of Protected Resources, NMFS at 301-427-8401 and/or by email to
Jolie.Harrison@noaa.gov and Howard.Goldstein@noaa.gov and the West
Coast Regional Stranding Coordinator (562-980-3230). The report must
include the following information:
Time, date, and location (latitude/longitude) of the
incident;
Type of activity involved;
Description of the circumstances during and leading up to
the incident;
Status of all sound source use in the 24 hours preceding
the incident;
Water depth;
Environmental conditions (e.g., wind speed and direction,
Beaufort sea state, cloud cover, and visibility);
Description of all marine mammal observations in the 24
hours preceding the incident;
Species identification or description of the animal(s)
involved;
Fate of the animal(s); and
Photographs or video footage of the animal(s) (if
equipment is available).
Activities shall not resume until NMFS is able to review the
circumstances of the prohibited take. NMFS shall work with ExxonMobil
to determine what is necessary to minimize the likelihood of further
prohibited take and ensure MMPA compliance. ExxonMobil may not resume
their activities until notified by NMFS via letter or email, or
telephone.
Reporting an Injured or Dead Marine Mammal with an Unknown Cause of
Death--In the event that ExxonMobil 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 (i.e., in less than
a moderate state of decomposition as described in the next paragraph),
ExxonMobil will immediately report the incident to the Chief of the
Permits and Conservation Division, Office of Protected Resources, NMFS,
at 301-427-8401, and/or by email to Jolie.Harrison@noaa.gov and
Howard.Goldstein@noaa.gov, and the NMFS West Coast Regional Office (1-
866-767-6114) and/or to the West Coast Regional Stranding Coordinator
(562-980-3230). The report must include the same information identified
in the paragraph above. Activities may continue while NMFS reviews the
circumstances of the incident. NMFS will work with ExxonMobil to
determine whether modifications to the activities are appropriate.
Reporting an Injured or Dead Marine Mammal Not Related to the
Activities--In the event that ExxonMobil 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 IHA
(e.g., previously wounded animal, carcass with moderate or advanced
decomposition, or scavenger damage), ExxonMobil will report the
incident to the Chief of the Permits and Conservation Division, Office
of Protected Resources, NMFS, at 301-427-8401, and/or by email to
Jolie.Harrison@noaa.gov and Howard.Goldstein@noaa.gov, and the NMFS
West coast Regional Office (1-866-767-6114) and/or to the West Coast
Regional Stranding Coordinator (562-980-3230), within 24 hours of
discovery. ExxonMobil will provide photographs or video footage (if
available) or other documentation of the stranded animal sighting to
NMFS and the Marine Mammal Stranding Network. Activities may continue
while NMFS reviews the circumstances of the incident.

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 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].

Table 6--NMFS's Current Underwater and In-Air Acoustic Exposure Criteria
------------------------------------------------------------------------
Criterion
Criterion definition Threshold
------------------------------------------------------------------------
Impulsive (Non-Explosive) Sound
------------------------------------------------------------------------
Level A harassment (injury)..... Permanent 180 dB re 1 [mu]Pa-
threshold shift m (root means
(PTS) (Any level square [rms])
above that which (cetaceans).
is known to cause 190 dB re 1 [mu]Pa-
TTS). m (rms)
(pinnipeds).
Level B harassment.............. Behavioral 160 dB re 1 [mu]Pa-
disruption (for m (rms).
impulsive noise).
Level B harassment.............. Behavioral 120 dB re 1 [mu]Pa-
disruption (for m (rms).
continuous noise).
------------------------------------------------------------------------
In-Air Sound
------------------------------------------------------------------------
Level A harassment.............. NA................ NA.
Level B harassment.............. Behavioral 90 dB re 20 [mu]Pa
disruption. (harbor seals).
100 dB re 20
[mu]Pa (all other
pinniped
species).
NA (cetaceans).
------------------------------------------------------------------------

Level B harassment is anticipated and authorized as a result of the
conductor pipe installation activities at the Harmony Platform in the
Santa Barbara Channel offshore of California. Acoustic stimuli (i.e.,
increased underwater and in-air sound) generated during the pipe-
driving activities are expected to result in the behavioral disturbance
of some marine mammals. There is no evidence that the planned
activities could result in injury, serious injury, or mortality for
which ExxonMobil seeks the IHA. The required mitigation and monitoring
measures will minimize any potential risk for injury, serious injury,
or mortality.

[[Page 58940]]

The following sections describe ExxonMobil and NMFS's methods to
estimate take by incidental harassment and present the total take
authorized incidental to the conductor pipe installation activities at
the Harmony Platform in the Santa Barbara Channel offshore of
California. The estimated takes were calculated using information on
sound source levels, sound propagation, maximum distances from the
sound source to Level A and Level B harassment exposure thresholds, and
estimated density of marine mammals in the action area. Take estimates
were calculated for in-water (cetaceans and pinnipeds) and in-air
(pinnipeds only). The estimates are based on the following information:
Thresholds for marine mammals to in-water and in-air
noise;
Sound levels at the conductor pipe from hammer strike;
Sound propagation (transmission/spreading loss) through
the environment (i.e., air, water);
Maximum distances from the sound sources to the
corresponding impact zones (based on Level A and Level B harassment
thresholds) for marine mammals;
Density estimate for each species of marine mammals
(calculated as stock abundance divided by 12,592 km\2\ [3,671.2
nmi\2\]area [except where noted]); and
Number of takes for each species of marine mammals within
a group (calculated as density multiplied by buffer/exclusion zone
multiplied by days of activity).
Sound levels for impulsive (impact) pipe-driving by the hammer and
propagation through water and in-air at the Harmony Platform were
modeled by JASCO Applied Sciences, Ltd. The modeling results are
presented in JASCO's acoustic modeling report as an addendum to the IHA
application titled ``Assessment of Airborne and Underwater Noise from
Pile Driving Activities at the Harmony Platform.'' Methods used to
estimate marine mammal densities and takes for the action area in the
Santa Barbara Channel are presented in Sections 6.1.5 and 6.1.6 of the
IHA application for likely exposures to species of marine mammals.
Densities of marine mammal species likely to occur in the action
area of the Santa Barbara Channel were taken directly from scientific
literature or calculated using corresponding abundances in NMFS Stock
Assessment Reports. Density estimates for sperm and Baird's beaked
whale, and short-beaked common, Pacific white-sided, Risso's, and
northern right whale dolphin, and Dall's porpoise were determined using
the Strategic Environmental and Development Program (SERDP)/National
Aeronautics and Space Administration (NASA)/NOAA Marine Animal Mapper
and OBIS-SEAMAP database using NMFS Southwest Fisheries Science Center
(SWFSC) summer densities for the California Current ecosystem. Density
estimates for the blue, fin, and humpback whale were taken directly
from Redfern et al. (2013), using the upper limit reported for the
density contour that includes the Harmony Platform. Redfern et al.
(2013) estimated densities for these three species using NMFS sightings
collected from primarily August through November over a period from
1991 to 2009 throughout the Santa Barbara Channel. Results for blue,
fin, and humpback whales are presented in Figures 6-3, 6-4, and 6-5 of
the IHA application. These densities are considered more accurate than
those based on reported stock abundances because even though they are
for the same monthly period and geographical location, they include a
correction factor to correct for non-observational periods. For
calculated densities of likely affected marine mammal species, stock
abundances, which generally range from the state of Washington to
northern Baja California, Mexico, were assumed to be concentrated
within the 12,593 km\2\ (3,671.5 nmi\2\) action area in the Santa
Barbara Channel. The action area includes the Harmony Platform, and
extends 18 km (9.7 nmi) to the north, 60 km (32.4 nmi) to the west, and
70 km (37.8 nmi) to the south of Point Conception, California. The
eastern boundary is 35 km (18.9 nmi) east of Anacapa Island. Use of
this area produces a conservative density estimate because the
geographical range of each marine mammal species evaluated is much
greater than 70 km (nmi) of the coastline selected to represent the
action area, including season-specific ranges for species that migrate
(e.g., gray whale). For marine mammal species potentially exposed to
in-air noise, pinniped densities were calculated by dividing the stock
abundance for each marine mammal species by the 1,130 m\2\ (12,163.2
ft\2\) impact area of the Harmony Platform near sea level where the
animals could potentially haul-out and/or have their heads out of the
water. Tables 6-7 and 6-8 of the IHA application describe the
calculated densities and estimated take by marine mammal species as
well as associated data for the in-water and in-air sound thresholds,
respectively. Although there is some uncertainty about the
representativeness of the data and the assumptions used in the
calculations below, the approach used here is believed to be the best
available approach.

Table 7--Estimated Densities and Possible Number of Marine Mammal Species That Might Be Exposed to Greater Than or Equal to 160 dB (Pipe-Driving
Activities) During Exxonmobil's Conductor Pipe Installation Activities in the Santa Barbara Channel Offshore of California
--------------------------------------------------------------------------------------------------------------------------------------------------------
Calculated take
from pipe-driving
activities in-air
Calculated take (i.e., estimated
from pipe-driving number of Approximate
Density in activities in- individuals percentage of
action area water (i.e., exposed to sound Total population/ Population trend
Species (/ estimated number levels >=90 dB re authorized Abundance \7\ stock estimate \7\
km\2\)\1\ of individuals 20 [mu]Pa for Take \6\ (for
exposed to sound harbor seals and authorized
levels >=160 dB 90 dB re 20 take) \8\
re 1 [mu]Pa) \4\ [mu]Pa for all
other pinnipeds)
\5\
--------------------------------------------------------------------------------------------------------------------------------------------------------
Mysticetes
--------------------------------------------------------------------------------------------------------------------------------------------------------
North Pacific right whale....... NA 0 0 0 NA (26)--Eastern NA NA.
North Pacific
stock.

[[Page 58941]]

Eastern North Pacific Gray whale 1.5188 3.063 0 10 19,126 (18,107)-- 0.05 Increasing over
Eastern North past several
Pacific stock 155 decades--Eastern
(142)--Western North Pacific
North Pacific stock.
population.
Humpback whale.................. \3\ 0.0055 0.0332 0 2 1,918 (1,855)--CA/ 0.1 Increasing.
OR/WA stock.
Minke whale..................... 0.04 0.2418 0 2 478 (202)--CA/OR/ 0.42 NA.
WA stock.
Bryde's whale................... NA 0 0 2 NA................ NA NA.
Sei whale....................... 0.01 0.0605 0 2 126 (83)--Eastern 1.58 NA.
North Pacific
stock.
Fin whale....................... \3\ 0.0065 0.0392 0 2 3,051 (2,598)--CA/ 0.07 Increasing.
OR/WA stock.
Blue whale...................... \2\ 0.006 0.00362 0 2 1,647 (1,551)-- 0.12 NA.
Eastern North
Pacific stock.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Odontocetes
--------------------------------------------------------------------------------------------------------------------------------------------------------
Sperm whale..................... \2\ 0.000327 0 2 971 (751)--CA/OR/ 0.21 NA.
0.0000542 WA stock.
Pygmy sperm whale............... 0.05 0.302 0 1 579 (271)--CA/OR/ 0.17 NA.
WA stock.
Dwarf sperm whale............... NA 0 0 0 NA--CA/OR/WA stock NA NA.
Baird's beaked whale............ \2\ 0.0074 0 6 847 (466)--CA/OR/ 0.71 NA.
0.001224 WA stock.
Cuvier's beaked whale........... 0.5233 3.1633 0 4 6,590 (4,481)--CA/ 0.06 Declining off CA/
OR/WA stock. OR/WA.
Mesoplodon beaked whale......... 0.0551 0.3331 0 2 694 (389)--CA/OR/ 0.29 Declining off CA/
WA stock. OR/WA.
Killer whale.................... 0.07464 0.4512 0 10 240 (162)--Eastern 4.17/2.89/2.82 NA--Eastern North
North Pacific Pacific Offshore
stock 346 (346)-- stock; NA--
Eastern North Eastern North
Pacific Transient Pacific Transient
stock 354 (354)-- stock;
West Coast Increasing--West
Transient stock. Coast Transient
stock.
False killer whale.............. NA 0 0 50 NA................ NA NA.
Short-finned pilot whale........ 0.06 0.3627 0 40 760 (465)--CA/OR/ 5.26 NA.
WA stock.
Bottlenose dolphin.............. 0.0799 0.4829 0 10 1,006 (684)--CA/OR/ 0.99 NA--CA/OR/WA
WA stock. Offshore stock;
NA--CA Coastal
stock.
Striped dolphin................. \2\ 0.0164 0 20 10,908 (8,231)--CA/ 0.18 NA.
0.002711 OR/WA stock.
Short-beaked common dolphin..... \2\ 5.7186 0 450 411,211 (343,990)-- 0.11 Varies with
0.946007 CA/OR/WA stock. oceanographic
conditions.
Long-beaked common dolphin...... 8.5 51.3825 0 120 107,016 (76,224)-- 0.11 Increasing over
CA stock. last 30 years.
Pacific white-sided dolphin..... \2\ 0.4149 0 30 26,930 (21,406)-- 0.11 NA.
0.068630 CA/OR/WA stock.
Northern right whale dolphin.... \2\ 0043996 0.2659 0 100 8,334 (6,019)--CA/ 1.19 NA.
OR/WA stock.
Risso's dolphin................. \2\ 0.3223 0 10 6,272 (4,913)--CA/ 0.16 NA.
0.053323 OR/WA stock.
Dall's porpoise................. 0.028931 0.1749 0 50 42,000 (32,106)-- 0.12 NA.
CA/OR/WA stock.
Harbor porpoise................. 0 0 0 0 NA................ NA NA.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Pinnipeds
--------------------------------------------------------------------------------------------------------------------------------------------------------
California sea lion............. 23.6 142.662 17.997 143 + 18 = 296,750 (153,337)-- 0.05 Increasing.
161 U.S. stock.
Steller sea lion................ NA 0 0 0 49,685 (42,366)-- NA Declining--Western
Western stock stock;
58,334 (72,223)-- Increasing--Easte
Eastern stock. rn stock;
Declining in CA.
Pacific harbor seal............. 2.4 14.508 5.491 15 + 6 = 21 30,196 (26,667)-- 0.07 Increased 1981 to
CA stock. 2004.

[[Page 58942]]

Northern elephant seal.......... 9.85 59.5433 7.512 60 + 8 = 68 124,000 (74,913)-- 0.05 Increasing through
CA breeding stock. 2005.
Northern fur seal............... 0.79 4.7756 0.602 5 + 1 = 6 12,844 (6,722)-- 0.05 Increasing.
California stock.
Guadalupe fur seal.............. NA 0 0 0 7,408 (3,028)-- NA Increasing.
Mexico to CA
stock.
--------------------------------------------------------------------------------------------------------------------------------------------------------
NA = Not available or not assessed.
\1\ Planned action area (12,593 km\2\) in the Santa Barbara Channel off the coast of California.
\2\ OBIS-SEAMAP SERDP-SDSS NMFS SWFSC summer density data for the California Current ecosystem.
\3\ Redfern et al. (2013)
\4\ Calculated take is the estimated number of animals in the in-water ensonified buffer zone multiplied by the number of days (18.6).
\5\ Calculated take is the estimated number of animals in the in-air ensonified buffer zone multiplied by the number of days (18.6).
\6\ Authorized take includes calculated takes for animals in the ensonified in-water and in-air buffer zones. Authorized takes for cetaceans were
increased to account for group size.
\7\ NMFS Marine Mammal Stock Assessment Reports (Caretta et al., 2013)
\8\ Total authorized (and calculated) takes expressed as percentages of the species or stock.

Numbers of marine mammals that might be present and potentially
disturbed are estimated based on the available data about marine mammal
distribution and densities in the Santa Barbara Channel action area.
ExxonMobil estimated the number of different individuals of marine
mammal species that may be exposed to in-water and in-air sounds with
received levels greater than or equal to 160 dB re 1 [mu]Pa (rms) and
in-air sounds with received levels greater than or equal to 90 dB re 20
[mu]Pa (rms) (for harbor seals)/100 dB re 20 [mu]Pa (rms) (for all
other pinniped species) for impact hammer pipe-driving activities on
one or more occasions by considering the total marine area that will be
within the 160 dB in-water radius and 90 dB (for harbor seals)/100 dB
(for all other pinniped species) in-air radius around the impact hammer
pipe-driving on at least one occasion and the expected density of
marine mammals in the area (in the absence of the conductor pipe
installation activities). The number of possible exposures can be
estimated by considering the total marine area that will be within the
in-water 160 dB radius and in-air 90 dB (for harbor seals)/100 dB (for
all other pinniped species) radius around the impact hammer pipe-
driving activities. The in-water 160 dB and in-air 90dB (harbor seal)/
100 dB (for all other pinniped species) radii are based on acoustic
modeling data for the impact hammer pipe-driving activities that may be
used during the action (see the addendum to the IHA application). It is
unlikely that a particular animal will stay in the area during the
entire impact hammer pipe-driving activities.
The number of different individuals potentially exposed to received
levels greater than or equal to 160 dB re 1 [mu]Pa (rms) for in-water
noise and 90 dB re 20 [mu]Pa (rms) (for harbor seals)/100 dB re 20
[mu]Pa (rms) (for all other pinniped species) for in-air noise from
impact hammer pipe-driving activities was calculated by multiplying:
(1) The expected species density (in number/km\2\), times
(2) The anticipated area to be ensonified to that level during
conductor pipe installation (buffer zone = [pi] x [maximum
distance]\2\), times
(3) The number of days of the conductor pipe installation
activities.
NMFS notes that ExxonMobil had estimated the total number of days
of the conductor pipe installation activities as 4.125 in its
application, based on the total number of estimated hours of impact
pipe-driving. NMFS received comments during the public comment period
stating that this approach underestimates the number of days of actual
exposure to the installation activities because pipe-driving sessions
will be interspersed between periods of no pipe-driving. Specifically,
the Commission commented that ExxonMobil should have added 3.3 hours of
estimated pile-driving per section to 7.3 hours of downtime per section
for a total of 10.6 hours per section of pipe. Multiplying that by the
projected seven sections to be driven for each conductor pipe would
result in a total of 74.2 hours, which when divided by 24 hours per day
equates to 3.1 days of potential exposure per pipe. Using this method
would yield a total of 18.6 days of potential exposure (3.1 days per
conductor pipe multiplied by 6 pipes), which more accurately represents
the total duration of proposed conductor pipe installation activities
for all six conductor pipes. NMFS agrees, and revised the total number
of days of installation activities to 18.6.
Applying the approach described above, approximately 0.3318 km\2\
will be ensonified within the in-water 160 dB isopleth and
approximately 0.0053 km\2\/0.0475 km\2\ will be ensonified within the
in-air 90 dB (harbor seals)/100 dB (for all other pinniped species)
isopleths for impact hammer pipe-driving activities (assuming
omnidirectional spreading of sound from the conductor pipe) during the
conductor pipe installation activities. The take calculations within
the action area account for animals in the initial density snapshot and
account for new (i.e., turnover) or previously exposed animals over an
approximate 18.6 day period that approach and enter the area ensonified
above or equal to the 160 dB isopleth for in-water noise and 90/100 dB
isopleth for in-air noise from the impact hammer pipe-driving
activities; however, studies suggest that many marine mammals will
avoid exposing themselves to sounds at these levels, which suggests
that there will not necessarily be a large number of new animals
entering the action area once the conductor pipe installation
activities

[[Page 58943]]

started. Also, the approach assumes that no cetaceans or pinnipeds will
move away or toward the Harmony Platform. The take estimates represent
the number of individuals that are expected (in absence of conductor
pipe installation activities) to occur over an approximate 18.6 day
period of time in the waters that will be exposed to greater than or
equal to 160 dB (rms) in-water and greater than or equal to 90/100 dB
(rms) in-air for impact hammer pipe-driving activities.
ExxonMobil's estimates of exposures to various sound levels assume
that the planned activities will be carried out in full. The estimates
of the numbers of marine mammals potentially exposed to 160 dB (rms)
for in-water noise and 90 dB re 20 [mu]Pa (rms) (for harbor seals)/100
dB re 20 [mu]Pa (rms) (for all other pinniped species) for in-air noise
received levels are precautionary and probably overestimate the actual
numbers of marine mammals that could be involved. These estimates
include standard contingencies for weather, equipment, or mitigation
delays in the time planned for the planned activities. The authorized
takes were increased for certain marine mammal species (i.e., gray,
humpback, minke, sei, fin, blue, sperm, Baird's beaked, Cuvier's
beaked, Mesoplodont beaked, killer, and short-finned pilot whales and
bottlenose, striped, short-beaked common, long-beaked common, Pacific
white-sided, northern right whale, and Risso's dolphins and Dall's
porpoise) to account for group behavior. Based on recommendations from
the CCC received during the 30-day public comment period on the notice
of the proposed IHA (79 FR 36743, June 30, 2014), NMFS has authorized
takes for Bryde's whales and false killer whales, which are considered
warmer water species.
Table 7 shows the estimates of the number of different individual
marine mammals anticipated to be exposed to greater than or equal to
160 dB re 1 [mu]Pa (rms) for the conductor pipe installation activities
if no animals moved away from the Harmony Platform. No takes by Level A
harassment have been authorized. The total take authorization is given
in the fifth column of Table 7.

Encouraging and Coordinating Research

ExxonMobil will coordinate the planned marine mammal monitoring
program associated with the conductor pipe installation activities with
researchers and other parties that express interest in this activity,
area, and anthropogenic sound effects on marine mammals. ExxonMobil
will coordinate with applicable U.S. agencies (e.g., NMFS), and will
comply with their requirements.
ExxonMobil supports research on marine mammals and sound in the
environment through academic, industry, and private sector
collaborations. ExxonMobil is a founding member and largest contributor
to the Sound and Marine Life Joint Industry Program (JIP) through the
International Oil and Gas Producers (OGP), and the International
Association of Geophysical Contractors (IAGC). Through JIP and other
venues, ExxonMobil provides annual funding and support for fundamental
and applied scientific research to better understand the effects of
anthropogenic sound on marine life. ExxonMobil also conducts internal
research and monitoring programs specific to sound effects from
exploration and production activities. These efforts have helped
produce effective mitigation strategies and techniques to reduce
potential sound effects on marine mammals from their operations and
those from the oil and gas industry as a whole. More information on
selected examples of ExxonMobil's involvement and contributions to
scientific research on marine mammals and sound can be found in section
14 of the IHA application.

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

Section 101(a)(5)(D) of the MMPA also requires NMFS to determine
that the authorization will not have an unmitigable adverse effect on
the availability of marine mammal species or stocks for subsistence
use. There are no relevant subsistence uses of marine mammals
implicated by this action. Therefore, NMFS has determined that the
total taking of affected species or stocks will not have an unmitigable
adverse impact on the availability of such species or stocks for taking
for subsistence purposes.

Analysis and Determinations

Negligible Impact

Negligible impact is ``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'' (50 CFR 216.103). A
negligible impact finding is based on the lack of likely adverse
effects on annual rates of recruitment or survival (i.e., population-
level effects). An estimate of the number of Level B harassment takes,
alone, is not enough information on which to base an impact
determination. In addition to considering estimates of the number of
marine mammals that might be ``taken'' through behavioral harassment,
NMFS must consider other factors such as the likely nature of any
responses (their intensity, duration, etc.), the context of any
responses (critical reproductive time or location, migration, etc.), as
well as the number and nature of estimated Level A harassment takes,
the number of estimated mortalities, and effects on habitat.
In making a negligible impact determination, NMFS evaluated factors
such as:
(1) The number of anticipated injuries, serious injuries, or
mortalities;
(2) The number, nature, and intensity, and duration of Level B
harassment (all relatively limited); and
(3) The context in which the takes occur (i.e., impacts to areas of
significance, impacts to local populations, and cumulative impacts when
taking into account successive/contemporaneous actions when added to
baseline data);
(4) The status of stock or species of marine mammals (i.e.,
depleted, not depleted, decreasing, increasing, stable, impact relative
to the size of the population);
(5) Impacts on habitat affecting rates of recruitment/survival; and
(6) The effectiveness of monitoring and mitigation measures.
As described above and based on the following factors, the
specified activities associated with the conductor pipe installation
activities are not likely to cause PTS, or other non-auditory injury,
serious injury, or death. The factors include:
(1) The likelihood that marine mammals are expected to move away
from a noise source that is annoying prior to its becoming potentially
injurious;
(2) The potential for temporary or permanent hearing impairment is
relatively low and will likely be avoided through the implementation of
the required monitoring and mitigation (i.e., shut-down) measures;
(3) The fact that cetaceans and pinnipeds will have to be closer
than 10 m and 3.5 m, respectively, during impact hammer pipe-driving
activities to be exposed to levels of underwater sound believed to have
a minimal chance of causing a permanent threshold shift (PTS; i.e.,
Level A harassment); and
(4) The likelihood that marine mammal detection ability by trained

[[Page 58944]]

PSOs is high at close proximity to the platform.
No injuries, serious injuries, or mortalities are anticipated to
occur as a result of ExxonMobil's planned conductor pipe installation
activities, and none are authorized by NMFS. Table 7 of this document
outlines the number of authorized Level B harassment takes that are
anticipated as a result of these activities. NMFS's practice has been
to apply the 160 dB re 1 [mu]Pa (rms) received level threshold for
underwater impulse sound levels to determine whether take by Level B
harassment occurs. Southall et al. (2007) provide a severity scale for
ranking observed behavioral responses of both free-ranging marine
mammals and laboratory subjects to various types of anthropogenic sound
(see Table 4 in Southall et al. [2007]). Current NMFS practice,
regarding exposure of marine mammals to high-level in-air sounds, as a
threshold for potential Level B harassment, is at or above 90 dB re 20
[mu]Pa for habor seals and at or above 100 dB re 20 [mu]Pa for all
other pinniped species (Lawson et al., 2002; Southall et al., 2007).
NMFS has not determined Level A harassment thresholds for marine
mammals for in-air noise.
As mentioned previously, NMFS estimates that 32 species of marine
mammals under its jurisdiction could be potentially affected by Level B
harassment over the course of the IHA. The population estimates for the
marine mammal species that may be taken by Level B harassment were
provided in Table 4 and 7 of this document. Due to the nature, degree,
and context of Level B (behavioral) harassment anticipated and
described (see ``Potential Effects on Marine Mammals'' section above)
in this notice, the planned activity is not expected to impact rates of
annual recruitment or survival for any affected species or stock,
particularly given NMFS's and the applicant's requirement to implement
mitigation, monitoring, and reporting measures to minimize impacts to
marine mammals. Additionally, the conductor pipe installation
activities will not adversely impact marine mammal habitat.
For the marine mammal species that may occur within the action
area, there are no known designated or important feeding and/or
reproductive areas. Many animals perform vital functions, such as
feeding, resting, traveling, and socializing, on a diel cycle (i.e., 24
hr cycle). Behavioral reactions to noise 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).
Potential impacts are not likely to be significant from the pipe-
driving activities as the use of the impact hammer will occur over 30
intermittent intervals of 2.5 to 3.3 hours each interspersed with
period of downtime, for a cumulative total of about 18.6 days of
potential exposure spread out over a 91-day period. Additionally, the
conductor pipe installation activities will be increasing sound levels
in the marine environment in a relatively small area surrounding the
Harmony Platform (compared to the range of the animals), and some
animals may only be exposed to and harassed by sound for less than a
day.
Of the 37 marine mammal species under NMFS jurisdiction that may or
are known to likely to occur in the action area, seven are listed as
threatened or endangered under the ESA: North Pacific right, western
North Pacific gray whale, humpback, sei, fin, blue, and sperm whale and
Guadalupe fur seal. These species are also considered depleted under
the MMPA. Of these ESA-listed species, incidental take has been
requested to be authorized for humpback, sei, fin, blue, and sperm
whales. There is generally insufficient data to determine population
trends for the other depleted species in the action area. To protect
these animals (and other marine mammals in the action area), ExxonMobil
must cease impact hammer pipe-driving activities if any marine mammal
enters designated exclusion zones. No injury, serious injury, or
mortality is expected to occur and due to the nature, degree, and
context of the Level B harassment anticipated, and the activities are
not expected to impact rates of recruitment or survival.
NMFS has determined, provided that the aforementioned mitigation
and monitoring measures are implemented, the impact of conducting pipe-
driving activities in the Santa Barbara Channel off the coast of
California, may result, at worst, in a modification in behavior and/or
low-level physiological effects (Level B harassment) of certain species
of marine mammals.
Changes in diving/surfacing patterns, habitat abandonment due to
loss of desirable acoustic environment, and cessation of feeding or
social interaction are some of the significant behavioral modifications
that could potentially occur as a result of the conductor pipe
installation activities. While behavioral modifications, including
temporarily vacating the area during the impact hammer pipe-driving
activities, may be made by these marine mammal species to avoid the
resultant acoustic disturbance, the availability of alternate areas
within these areas for species and the short and sporadic duration of
the conductor pipe installation activities have led NMFS to determine
that the taking by Level B harassment from the specified activity will
have a negligible impact on the affected species in the specified
geographic region. NMFS believes that the length of the conductor pipe
installation activities (approximately 18.6 days total), the
requirement to implement mitigation measures (e.g., shut-down of impact
hammer pipe-driving activities), and the inclusion of the monitoring
and reporting measures, will reduce the amount and severity of the
potential impacts from the activity to the degree that it will have a
negligible impact on the species or stocks in the action area. 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 required monitoring and
mitigation measures, NMFS finds that the total marine mammal take from
ExxonMobil's conductor pipe installation activities will have a
negligible impact on the affected marine mammal species or stocks.

Small Numbers

The estimate of the number of individual cetaceans and pinnipeds
that could be exposed to pipe-driving sounds with received levels
greater than or equal to 160 dB re 1 [mu]Pa (rms) for all marine
mammals for in-water sound levels and at or above 90 dB re 20 [mu]Pa
for harbor seals and at or above 100 dB re 20 [mu]Pa for all other
pinniped species for in-air sound levels during the conductor pipe
installation activities is in Table 7 of this document.
In total, 10 gray, 2 humpback, 2 minke, 2 Bryde's, 2 sei, 2 fin, 2
blue, and 2 sperm whale could be taken by Level B harassment during the
conductor pipe installation activities, which will represent 0.05,
0.05, 0.2, unknown, 0.8, 0.03, 0.06, and 0.21% of the stock
populations, respectively. Some of the cetaceans potentially taken by
Level B harassment are delphinids and porpoises with estimates of 1
pygmy sperm, 6 Baird's beaked, 4 Cuvier's beaked, 2 Mesoplodon spp.
beaked, 10 killer, 50 false killer, and 40 short-finned pilot whale, 10
bottlenose, 20 striped, 450 short-beaked common, 120 long-beaked
common, 20 Pacific white-sided, 100 northern right whale, and 10
Risso's dolphin as well as 50 Dall's porpoise, which will represent
0.17, 0.71, 0.06, 0.29, 4.17/2.89/2.82, unknown, 5.26, 0.99, 0.18,
0.11, 0.11,

[[Page 58945]]

0.11, 1.19, 0.16, and 0.12% of the affected stock populations,
respectively. The pinnipeds that could potentially be taken by Level B
harassment are the California sea lion, Pacific harbor and northern
elephant seal, and northern fur seal with estimates of 161, 21, 68, and
6 individuals, which will represent 0.05, 0.07, 0.05, and 0.05% of the
affected stock populations, respectively.
NMFS has determined that the authorized take estimates represent
small numbers relative to the affected species or stocks sizes (i.e.,
all are less than 6%). 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 finds that small numbers of
marine mammals will be taken relative to the populations of the
affected species or stocks. See Table 7 for the authorized take numbers
of marine mammals.
No known current regional population or stock abundance estimates
for the northeast Pacific Ocean offshore of California are available
for the two species under NMFS's jurisdiction that could potentially be
affected by Level B harassment over the course of the IHA. These
species include the Bryde's whale and false killer whale. Bryde's
whales are distributed worldwide in tropical and sub-tropical waters
and their occurrence in the action area is rare. Surveys have shown
them to be common and distributed throughout the eastern tropical
Pacific Ocean with a concentration around the equator east of 110[deg]
West and a reduction west of 140[deg] West. Bryde's whales in
California are likely to belong to a larger population inhabiting at
least the eastern part of the tropical Pacific Ocean. In the western
North Pacific Ocean, Bryde's whale abundance in the early 1980s was
estimated to be 22,000 to 24,000 (Tillman and Mizroch, 1982; Miyashita,
1986). Bryde's whale abundance has never been estimated for the entire
eastern Pacific Ocean; however, a portion of that stock in the eastern
tropical Pacific Ocean was estimated as 13,000 (Wade and Gerrodette,
1993). The false killer whale is distributed worldwide throughout warm
temperate and tropical oceans and their occurrence in the action area
is rare. In the North Pacific Ocean, this species is well known from
southern Japan, Hawaii, and the eastern tropical Pacific Ocean. This
species occurs in the U.S. waters of the northern Gulf of Mexico,
Hawaiian Islands, around Palmyra and Johnston Atolls, and American
Samoa.
These two species did not have density model outputs within the
SERDP/NASA/NOAA and OBIS-SEAMAP database. However, limited OBIS-SEAMAP
sightings data exist for these species within or adjacent to the action
area. Even where the limited number of sightings suggests that density
is very low and encounters are less likely, for any species with OBIS-
SEAMAP sightings data within or adjacent to the action area, NMFS
believes it is wise to include coverage for potential takes. Generally,
to quantify this coverage, NMFS assumed that ExxonMobil could
potentially encounter one group of each species during the conductor
pipe installation activities, and NMFS thinks it is reasonable to use
the average group size to estimate the take from these potential
encounters. Therefore, even though we do not have abundance data for
these species, because of the limited sightings and low probability of
encountering them, we have predicted take of no more than one
individual group of each of these species of animals during the
conductor pipe installation activities. Qualitatively, given what is
known about cetacean biology and the range of these species, one group
as a portion of the total population abundance within the U.S. EEZ
would be considered small for both species.

Endangered Species Act

Of the species of marine mammals that may occur in the action area,
several are listed as threatened or endangered under the ESA, including
the North Pacific right, western North Pacific gray, humpback, sei,
fin, blue, and sperm whale and Guadalupe fur seal. ExxonMobil did not
request take of endangered North Pacific right whales, western North
Pacific gray whales, or Guadalupe fur seals due to the low likelihood
of encountering these species during the pipe-driving activities.
NMFS's Office of Protected Resources, Permits and Conservation
Division, initiated formal consultation under section 7 of the ESA with
NMFS's West Coast Regional Office, Protected Resources Division, to
obtain a Biological Opinion evaluating the effects of issuing the IHA
to ExxonMobil under section 101(a)(5)(D) of the MMPA on threatened and
endangered marine mammals. NMFS's Biological Opinion concluded that the
action and issuance of the IHA are not likely to jeopardize the
continued existence of listed species and included an Incidental Take
Statement incorporating the requirements of the IHA as Terms and
Conditions. The Biological Opinion also concluded that designated
critical habitat of these species does not occur in the action area.

National Environmental Policy Act

To meet National Environmental Policy Act (NEPA; 42 U.S.C. 4321 et
seq.) requirements published by the Council of Environmental Quality
(CEQ) and NOAA Administrative Order 126-6, Environmental Review
Procedures for Implementing the National Environmental Policy Act, NMFS
conducted a NEPA analysis to evaluate the effects of authorizing the
take of marine mammals. NMFS prepared an Environmental Assessment
titled ``Environmental Assessment on the Issuance of an Incidental
Harassment Authorization to ExxonMobil Production Company to Take
Marine Mammals by Harassment Incidental to Conductor Pipe Installation
Activities at Harmony Platform in the Santa Barbara Channel offshore of
California.'' NMFS has determined that the issuance of the IHA is not
likely to result in significant impacts on the human environment and
issued a Finding of No Significant Impact (FONSI).

Authorization

NMFS has issued an IHA to ExxonMobil for the take, by Level B
harassment, of small numbers of marine mammals incidental to conducting
conductor pipe installation activities at Harmony Platform in Santa
Barbara Channel offshore of California, provided the previously
mentioned mitigation, monitoring, and reporting requirements are
incorporated.

Dated: September 19, 2014.
Perry F. Gayaldo,
Deputy Director, Office of Protected Resources, National Marine
Fisheries Service.
[FR Doc. 2014-22758 Filed 9-29-14; 8:45 am]
BILLING CODE 3510-22-P

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