Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to Construction Activities Associated With the Raritan Bay Pipeline, 45955-45983 [2019-18931]

Agencies

• DEPARTMENT OF COMMERCE
• National Oceanic and Atmospheric Administration

[Federal Register Volume 84, Number 170 (Tuesday, September 3, 2019)]
[Notices]
[Pages 45955-45983]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2019-18931]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

RIN 0648-XF505


Takes of Marine Mammals Incidental to Specified Activities; 
Taking Marine Mammals Incidental to Construction Activities Associated 
With the Raritan Bay Pipeline

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

ACTION: Notice; proposed incidental harassment authorization; request 
for comments on proposed authorization and possible renewal.

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SUMMARY: NMFS has received a request from Transcontinental Gas Pipe 
Line Company, LLC (Transco), a subsidiary of Williams Partners L.P., to 
take marine mammals incidental to construction activities associated 
with the Raritan Bay Pipeline. Pursuant to the Marine Mammal Protection 
Act (MMPA), NMFS is requesting comments on its proposal to issue an 
incidental harassment authorization (IHA) to incidentally take marine 
mammals during the specified activities. NMFS is also requesting 
comments on a possible one-year renewal that could be issued under 
certain circumstances and if all requirements are met, as described in 
Request for Public Comments at the end of this notice. NMFS will 
consider public comments prior to making any final decision on the 
issuance of the requested MMPA authorizations and agency responses will 
be summarized in the final notice of our decision.

DATES: Comments and information must be received no later than October 
3, 2019.

ADDRESSES: Comments should be addressed to Jolie Harrison, Chief, 
Permits and Conservation Division, Office of Protected Resources, 
National Marine Fisheries Service. Physical comments should be sent to 
1315 East-West Highway, Silver Spring, MD 20910 and electronic comments 
should be sent to [email protected].
    Instructions: NMFS is not responsible for comments sent by any 
other method, to any other address or individual, or received after the 
end of the comment period. Comments received electronically, including 
all attachments, must not exceed a 25-megabyte file size. Attachments 
to electronic comments will be accepted in Microsoft Word or Excel or 
Adobe PDF file formats only. All comments received are a part of the 
public record and will generally be posted online at 
www.fisheries.noaa.gov/permit/incidental-take-authorizations-under-marine-mammal-protection-act without change. All personal identifying 
information (e.g., name, address) voluntarily submitted by the 
commenter may be publicly accessible. Do not submit confidential 
business information or otherwise sensitive or protected information.

FOR FURTHER INFORMATION CONTACT: Jordan Carduner, Office of Protected 
Resources, NMFS, (301) 427-8401. Electronic copies of the application 
and supporting documents, as well as a list of the references cited in 
this document, may be obtained online at: www.fisheries.noaa.gov/permit/incidental-take-authorizations-under-marine-mammal-protection-act. In case of problems accessing these documents, please call the 
contact listed above.

SUPPLEMENTARY INFORMATION: 

Background

    The MMPA prohibits the ``take'' of marine mammals, with certain

[[Page 45956]]

exceptions. Sections 101(a)(5)(A) and (D) of the MMPA (16 U.S.C. 1361 
et seq.) direct the Secretary of Commerce (as delegated to NMFS) to 
allow, upon request, the incidental, but not intentional, taking of 
small numbers of marine mammals by U.S. citizens who engage in a 
specified activity (other than commercial fishing) within a specified 
geographical region if certain findings are made and either regulations 
are issued or, if the taking is limited to harassment, a notice of a 
proposed incidental take authorization may be provided to the public 
for review.
    Authorization for incidental takings shall be granted if NMFS finds 
that the taking will have a negligible impact on the species or 
stock(s) and will not have an unmitigable adverse impact on the 
availability of the species or stock(s) for taking for subsistence uses 
(where relevant). Further, NMFS must prescribe the permissible methods 
of taking and other ``means of effecting the least practicable adverse 
impact'' on the affected species or stocks and their habitat, paying 
particular attention to rookeries, mating grounds, and areas of similar 
significance, and on the availability of such species or stocks for 
taking for certain subsistence uses (referred to in shorthand as 
``mitigation''); and requirements pertaining to the mitigation, 
monitoring and reporting of such takings are set forth.
    The definitions of all applicable MMPA statutory terms cited above 
are included in the relevant sections below.

National Environmental Policy Act

    To comply with the National Environmental Policy Act of 1969 (NEPA; 
42 U.S.C. 4321 et seq.) and NOAA Administrative Order (NAO) 216-6A, 
NMFS must evaluate our proposed action (i.e., the promulgation of 
regulations and subsequent issuance of incidental take authorization) 
and alternatives with respect to potential impacts on the human 
environment.
    This action is consistent with categories of activities identified 
in Categorical Exclusion B4 of the Companion Manual for NAO 216-6A, 
which do not individually or cumulatively have the potential for 
significant impacts on the quality of the human environment and for 
which we have not identified any extraordinary circumstances that would 
preclude this categorical exclusion. Accordingly, NMFS has 
preliminarily determined that the proposed action qualifies to be 
categorically excluded from further NEPA review.
    Information in Transco's application and this notice collectively 
provide the environmental information related to proposed issuance of 
these regulations and subsequent incidental take authorization for 
public review and comment. We will review all comments submitted in 
response to this notice prior to concluding our NEPA process or making 
a final decision on the request for incidental take authorization.

Summary of Request

    On February 7, 2019, NMFS received a request from Transco for an 
IHA to take marine mammals incidental to construction activities 
associated with the Raritan Bay Loop pipeline offshore of New York and 
New Jersey. Transco submitted a revised version of the application on 
May 23, 2019, and this application was deemed adequate and complete. 
Transco's request is for take of 10 species of marine mammals by 
harassment. Neither Transco nor NMFS expects serious injury or 
mortality to result from this activity and, therefore, an IHA is 
appropriate.

Description of Proposed Activity

Overview

    Transco, a subsidiary of Williams Partners L.P., is proposing to 
expand its existing interstate natural gas pipeline system in 
Pennsylvania and New Jersey and its existing offshore natural gas 
pipeline system in New Jersey and New York waters. The Northeast Supply 
Enhancement Project would consist of several components, including 
offshore pipeline facilities in New Jersey and New York. The proposed 
offshore pipeline facilities would include the Raritan Bay Loop 
pipeline, which would be located primarily in Raritan Bay, as well as 
parts of the Lower New York Bay and the Atlantic Ocean.
    Construction of the Raritan Bay Loop pipeline would require pile 
installation and removal, using both impact and vibratory pile driving, 
which may result in the incidental take of marine mammals. Transco 
would install and remove a total of 163 piles, which would range in 
size from 10 to 60 inches in diameter, using a vibratory device and/or 
diesel impact hammer. These piles would be temporary; they would remain 
in the water only for the duration of each related offshore 
construction activity. Once offshore construction of the project is 
complete, all piles installed by Transco would be removed.

Dates and Duration

    In-water construction is anticipated to occur between the 2nd 
quarter of 2020 and the 4th quarter of 2020. Pile installation and 
removal activities are planned to occur from June through August 2020. 
However the timeframe for pile removal may occur in fall 2020. Pile 
installation and removal activities are expected to take a total of 
65.5 days.

Specific Geographic Region

    Transco's proposed activity would occur in the waters of Raritan 
Bay, the Lower New York Bay, and the Atlantic Ocean (see Figure 1 in 
the IHA application). The Project area is located in the greater New 
York Bight region. The New York Bight is a triangular-shaped area of 
the continental shelf generally bounded by Montauk Point on eastern 
Long Island, Cape May in southern New Jersey, and the open shallows of 
the Atlantic Ocean. The depth of water in the area averages about 27 
meters (m) (90 feet (ft)), except in the northwest-southeast-trending 
Hudson Canyon, which has depths in excess of 73 m (240 ft) (Ketchem et 
al. 1951). The New York Bight refers to the bend, or curve, in the 
shoreline of the open coast and great expanse of shallow ocean between 
Long Island and the New Jersey coast. Water depths exceed 30 m (100 ft) 
approximately 80 kilometers (km) (50 statute miles) offshore.

Detailed Description of Specific Activity

    Transco is proposing to expand its existing interstate natural gas 
pipeline system in Pennsylvania and New Jersey and its existing 
offshore natural gas pipeline system in New Jersey and New York waters 
with the goal of providing an additional 400,000 dekatherms per day 
capacity to its customers. To provide this additional capacity, Transco 
proposes to expand portions of its system from an existing Compressor 
Station in York County, Pennsylvania, to the Rockaway Transfer Point in 
New York State waters, which represents the interconnection point 
between Transco's existing Lower New York Bay Lateral and the existing 
offshore Rockaway Delivery Lateral (RDL). The proposed project would 
consist of several components, including onshore pipeline facilities in 
Pennsylvania and New Jersey and offshore pipeline facilities in New 
Jersey and New York. Only the offshore pipeline components of the 
project have the potential to result in the take of marine mammals, 
thus the onshore components of the project are not analyzed further in 
this document.
    Transco's proposed offshore pipeline facilities include the Raritan 
Bay Loop pipeline, which would be located primarily in Raritan Bay as 
well as parts of the Lower New York Bay and the Atlantic Ocean. The 
Raritan Bay Loop would begin at the onshore connection

[[Page 45957]]

with the Madison Loop in Middlesex, New Jersey (see Figure 1 in the IHA 
application). The offshore portion of the Raritan Bay Loop would extend 
from the Sayreville shoreline approximately 37.6 km (23.3 mi) across 
Raritan Bay and Lower New York Bay to the Rockaway Transfer Point, 
which is the interconnection point with the RDL in New York State 
waters in the Atlantic Ocean, approximately 4.8 km (3 mi) seaward of 
Rockaway, New York. Approximately 9.6 km (6.0 mi) of the offshore 
portion of the Raritan Bay Loop route would cross New Jersey waters, 
while the remaining 28 km (17.4 mi) would cross New York waters. The 
Raritan Bay Loop would cross a continuous expanse of open marine and 
estuarine waters in New Jersey and New York, which consists of three 
major contiguous waterbodies, including Raritan Bay, Lower New York 
Bay, and the Atlantic Ocean (See Figures 1 and 2 in the IHA 
application). This area is part of the coastal region known as the New 
York Bight.
    Construction of the Raritan Bay Loop pipeline would require the 
installation of 163 piles, ranging in size from 10 to 60 inches in 
diameter, using a vibratory device and/or diesel impact hammer. Impact 
pile drivers are piston-type drivers that use various means to lift a 
piston to a desired height and drop the piston against the head of the 
pile in order to drive it into the substrate (Caltrans, 2015). Diesel 
impact hammers would be used to install approximately 34 steel piles 
(Table 1). A vibratory device uses spinning counterweights, causing the 
pile to vibrate at a high speed. The vibrating pile causes the soil 
underneath it to ``liquefy'' and allow the pile to move easily into or 
out of the sediment. Vibratory devices generally have source levels 10 
to 20 decibels (dB) lower than impact devices, so their use is 
considered a means to reduce overall underwater sound when pile driving 
is necessary for a project and suitable sediment conditions exist 
(Caltrans, 2015). Vibratory devices would be used to install and remove 
approximately 163 steel pipe piles (Table 1). Note that some piles 
would require both impact and vibratory installation.
    The total time to install a pile is dependent on the installation 
method (vibratory or impact), diameter of the pile, substrate 
composition, and depth the pile needs to penetrate through the 
substrate. For pile installation of 0.9- to 1.5-m (34- to 60-in) piles 
using a diesel impact hammer, the estimated time is 38 to 62 minutes 
per pile. For pile installation of 0.3- to 1.5-m (10- to 60-in) piles 
using a vibratory hammer, the estimated time is 15 minutes per pile. 
For pile removal of 0.3- to 1.5-m (10- to 60-in) piles using a 
vibratory hammer, the estimated time is 5 to 30 minutes per pile. The 
minimum handling time (i.e., periods during which the pile is being 
positioned, steadied, etc., and no in-water construction noise is 
anticipated) is dependent on activity type and pile size. For vibratory 
hammer periods for 0.3- to 1.2-m (10- to 48-in) piles, the handling 
time ranges from 15 to 45 minutes. For vibratory hammer periods for 
1.5-m (60-in) piles, the minimum handling time is 1 hour and 45 
minutes. For impact hammer periods, the minimum handling time is 30 
minutes. The total duration of pile installation (including both 
vibratory and impact pile driving) is estimated at 42.5 days. The piles 
would remain in the offshore environment only for the duration of each 
related offshore construction activity. Once offshore construction is 
complete, all piles would be removed using a vibratory hammer, which is 
expected to occur over an estimated 23 days. Thus the total duration of 
pile installation and removal is 65.5 days (i.e., 42.5 days for pile 
installation and 23 days for pile removal). Installation and removal of 
all piles is expected to be completed during summer 2020 (June-August); 
however, pile removal could shift to fall 2020 (September, October, 
and/or November), after finalization of the construction schedule.
    All piles would be installed along a string of locations within 
Raritan Bay (see Figure 2 in the IHA application). Transco would 
complete construction of the various components of the offshore 
pipeline in several stages with overlapping schedules. An overview of 
these stages and their general sequence are described below.
     Temporary fixed platform: During assembly of the fixed 
platform, vibratory and impact hammers would be used to install the 
steel piles; vibratory hammers would be used to remove the piles once 
the work is completed.
     Pre-trenching, cable crossings, and initial pipelay: 
Trenching for the offshore (subsea) pipeline would take place using a 
clamshell dredging device. One clamshell dredge with an environmental 
bucket and its supporting scows would be mobilized to first excavate a 
pit and trench at the offshore horizontal directional drill exit point 
for the Morgan Shore Approach horizontal directional drill (HDD). 
Transco would also mobilize a barge equipped with diving, jetting, and 
material-handling equipment to remove sediment that covers the first 
Neptune Cable crossing. Transco would then place concrete mattresses on 
either side of the cable in the excavated areas to create a bridge 
above the cable. Due to shallow water depths near the Morgan shoreline, 
a combination of the pipelay barge and the temporary fixed platform 
would install pipeline in this section of trench. Following completion 
of a successful hydrostatic test of the pipeline, a clamshell dredge 
would backfill the trench. A second clamshell dredge with an 
environmental bucket would begin trenching the Raritan Bay Channel and 
the Chapel Hill Channel crossing.
     HDD Crossings: For the Morgan Shore Approach HDD, Transco 
would mobilize a marine-support barge. The clamshell dredge (with 
environmental bucket) would excavate the exit point and then a 
vibratory device would be used to install the temporary fixed platform 
and the piles, known as ``goal posts,'' to guide the pipe at the exit 
point. Transco would assemble the HDD pipe string on the pipelay barge, 
a winch wire from the fixed platform would be attached to the HDD pipe 
string that would pull the pipe string into place with the aid of a tug 
on the tail end section, lay the pipe string on the seafloor, and then 
complete a hydrostatic test of the pipeline segment. For the Ambrose 
Channel crossing, Transco would mobilize a clamshell dredge with an 
environmental bucket and two liftboats with drilling equipment to the 
Lower New York Bay. The clamshell dredge would excavate pits at the 
east point and west point, and then a vibratory device would be used to 
install piles (goal posts) on opposite sides of the Ambrose Channel. 
Following the goal post installation, dolphin/fender piles (installed 
using a vibratory device and/or impact hammer), and a casing would be 
installed at both HDD pits. The HDD string would then be laid and 
pulled through.
     Additional Pipelay and Backfill: Following assembly and 
installation of the Ambrose Channel HDD described above, an anchored 
pipelay barge would begin laying pipe on the seafloor from the east 
Ambrose HDD pit to the Rockaway Neptune cable crossing. The anchored 
pipelay barge would then relocate to west of the Ambrose Channel entry 
HDD point and lay the pipeline from the west Ambrose HDD pit to the 
mid-line tie-in point at milepost (MP) 16.6. After Transco has laid the 
pipeline, Transco would use a jet trencher to lower the pipeline and a 
clamshell dredge would backfill the trench near the Ambrose Channel, 
Ambrose HDD pits, and navigation channels. Transco would bury the pipe 
to a minimum depth of 1.22 m (4 ft) (or

[[Page 45958]]

equivalent) and in accordance with any permit conditions as directed by 
the USACE.
     Subsea Manifold Tie-in, Hydrostatic Testing, and 
Commissioning: Hand jets would be used to expose the existing subsea 
manifold at the RDL, and a new tie-in valve spool would be installed. A 
tie-in skid and tie-in spools would be installed at the end of the 
Raritan Bay Loop. Transco would seal the Raritan Bay Loop pipeline 
between the onshore entry point and the tie-in skid and pre-
commissioning would then occur, which would include hydrostatic 
pressure testing of the new pipeline. After completion of the 
hydrostatic test, a final spool piece would be installed to connect the 
Raritan Bay Loop to the subsea manifold. The tie-in spools between the 
tie-in skid and tie-in valve spool would be dewatered, the manifold 
tie-in location would be backfilled, and Transco would introduce 
natural gas into the completed Raritan Bay Loop.
    The various components of the proposed construction of the Raritan 
Bay Loop pipeline, including pile type, size and quantity, installation 
method (i.e., impact or vibratory), and pile driving or removal 
duration, are shown in Table 1 and are described in greater detail in 
the IHA application.

                             Table 1--Pile Driving Summary for Raritan Bay Loop, Including Pile Types and Driving Durations
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                                                                                                               Installation                Removal
                                                                                                       -------------------------------------------------
                                                                  Diameter               Installation                                Removal
  Milepost          Site          Pile type         Purpose        (in.)     Quantity       method        Driving time    Duration     time     Duration
                                                                                                          per pile \c\     (days)     (min./     (days)
                                                                                                                            \d\       pile)       \d\
--------------------------------------------------------------------------------------------------------------------------------------------------------
12.59.......  Morgan Shore     Platform Piles   Temporary fixed         36         18  Vibratory &      V-15 Min/Pile..        4.5         30          3
               Approach HDD.    (for temporary   platform for                           Diesel Impact   I-52-62 Min/
                                fixed            Morgan Shore                           Hammer.          Pile \e\.
                                platform).       Approach HDD.
12.59.......  Morgan Shore     Platform         Provide                 36          4  Vibratory &      V-15 Min/Pile..          2         30
               Approach HDD.    Reaction Piles.  additional                             Diesel Impact   I-52-62 Min/
                                                 lateral                                Hammer.          Pile \e\.
                                                 capacity for
                                                 pipeline
                                                 pulling winch.
12.59.......  Morgan Shore     Support Barge    Tie up and           36-48          4  Vibratory        V-15 Min/Pile..          2         15
               Approach HDD.    Fender Piles.    breast support                         Hammer.
                                                 barge
                                                 alongside HDD
                                                 operations.
12.59.......  Morgan Shore     Water Barge      Tie up and           36-48          4  Vibratory        V-15 Min/Pile..                    15
               Approach HDD.    Fender Piles.    breast water                           Hammer.
                                                 barge
                                                 alongside HDD
                                                 operations.
12.59.......  Morgan Shore     HDD String Goal  Support HDD             24         10  Vibratory        V-15 Min/Pile..          3          5          3
               Approach HDD.    Posts.           string.                                Hammer.
13.84.......  Neptune Power    Sleeper          Provide                 10          8  Vibratory        V-15 Min/Pile..          2         15        1.5
               Cable Crossing   Vertical Pile.   mechanical                             Hammer.
               (MP13.84).                        protection to
                                                 ensure
                                                 separation
                                                 between
                                                 Neptune Power
                                                 cable and
                                                 pipeline.
14.5 to 16.5  MP14.5 to        Morgan Shore     Ensure pipeline         24         22  Vibratory        V-15 Min/Pile..          5         15        1.5
               MP16.5.          Pull Vertical    stays within                           Hammer.
                                Guide Piles.     pipeline
                                                 corridor
                                                 during surface
                                                 tow between
                                                 MP14.5 to
                                                 MP16.5.
28.0 to       MP28.0 to        Pipelay Barge    Assist pipelay          34         12  Vibratory        V-15 Min/Pile..          3         30          2
 29.36.        MP29.36.         Mooring Pile.    barge with                             Hammer.
                                                 mooring in
                                                 vicinity of
                                                 Ambrose
                                                 Shipping
                                                 Channel.
29.4........  Ambrose Channel  W750 Side Piles  Landing of              36          3  Vibratory        V-15 Min/Pile..        1.5         15        0.5
               HDD West Side.                    small barges/                          Hammer.
                                                 vessels
                                                 alongside
                                                 prior to
                                                 fender piles
                                                 being
                                                 installed.
29.4........  Ambrose Channel  Reaction Frame   Provide              36-60          8  Vibratory &      V-15 Min/Pile..          4         30        0.5
               HDD West Side.   Piles.           additional                             Diesel Impact   I-38 Min/Pile e
                                                 lateral                                Hammer.          f.
                                                 capacity for
                                                 HDD pipeline
                                                 pull.
29.4........  Ambrose Channel  Support Barge    Tie up and           36-48          4  Vibratory        V-15 Min/Pile..        1.5         15          1
               HDD West Side.   Fender Piles.    breast support                         Hammer.
                                                 barge
                                                 alongside HDD
                                                 operations.
29.4........  Ambrose Channel  Water Barge      Tie up and           36-48          4  Vibratory        V-15 Min/Pile..                    15
               HDD West Side.   Fender Piles.    breast water                           Hammer.
                                                 barge
                                                 alongside HDD
                                                 operations.
29.4........  Ambrose Channel  HDD String Goal  Support HDD             24         12  Vibratory        V-15 Min/Pile..        1.5          5          2
               HDD West Side.   Posts.           string.                                Hammer.
30.48.......  Ambrose Channel  Ambrose East     Ensure HDD              24         22  Vibratory        V-15 Min/Pile..          5         15        0.5
               HDD East Side.   Vertical         string is                              Hammer.
                                Stabilization    secured while
                                Piles.           awaiting
                                                 pullback.
30.48.......  Ambrose Channel  W751 Side Piles  Landing of              36          3  Vibratory        V-15 Min/Pile..        0.5         15        0.5
               HDD East Side.                    small barges/                          Hammer.
                                                 vessels
                                                 alongside
                                                 prior to
                                                 fender piles
                                                 being
                                                 installed.
30.48.......  Ambrose Channel  Support Barge    Tie up and           36-48          4  Vibratory        V-15 Min/Pile..          1         15          1
               HDD East Side.   Fender Piles.    breast support                         Hammer.
                                                 barge
                                                 alongside HDD
                                                 operations.
30.48.......  Ambrose Channel  HDD Drill        Support HDD             24         10  Vibratory        V-15 Min/Pile..        1.5          5          2
               HDD East Side.   String Goal      string.                                Hammer.
                                Posts.
30.48.......  Ambrose Channel  Pipelay Barge    Assist pipelay          60          1  Vibratory        V-15 Min/Pile          0.5         15          1
               HDD East Side.   Mooring Pile.    barge with                             Hammer.          \f\.
                                                 mooring at
                                                 Ambrose East.
34.5 to       MP34.5 to        Pipelay Barge    Assist pipelay          34          4  Vibratory &      V-15 Min/Pile..          3         15          2
 35.04.        MP35.04.         Mooring Pile.    barge with                             Diesel Impact   I-52 Min/Pile
                                                 mooring.                               Hammer.          \e\.

[[Page 45959]]

 
35.04.......  Neptune Power    Crossing Pile..  Ensure                  10          2  Vibratory        V-15 Min/Pile..          1         15          1
               Cable Crossing                    temporary                              Hammer.
               (MP35.04).                        stability of
                                                 pipeline at
                                                 crossing
                                                 location.
--------------------------------------------------------------------------------------------------------------------------------------------------------

    Underwater sound produced during impact pile driving and vibratory 
driving and removal could result in incidental take of marine mammals 
by Level B harassment and, for some species, Level A harassment.
    Proposed mitigation, monitoring, and reporting measures are 
described in detail later in this document (please see Proposed 
Mitigation and Proposed Monitoring and Reporting).

Description of Marine Mammals in the Area of Specified Activities

    Sections 3 and 4 of the IHA application summarize available 
information regarding status and trends, distribution and habitat 
preferences, and behavior and life history, of the potentially affected 
species. Additional information regarding population trends and threats 
may be found in NMFS' Stock Assessment Reports (SARs; 
www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments) and more general information about these species 
(e.g., physical and behavioral descriptions) may be found on NMFS' 
website (www.fisheries.noaa.gov/find-species).
    There are 42 marine mammal species that have been documented within 
the U.S. Atlantic Exclusive Economic Zone (EEZ). However, 29 of these 
species are not expected to occur within the project area, based on a 
lack of sightings in the area and their known habitat preferences and 
distributions, which are generally further offshore and at greater 
depths than the project area. These are: The blue whale (Balaenoptera 
musculus), sei whale (Balaenoptera borealis), Bryde's whale 
(Balaenoptera edeni), sperm whale (Physeter macrocephalus), dwarf and 
pygmy sperm whale (Kogia sima and Kogia breviceps), beluga whale 
(Delphinapterus leucas), northern bottlenose whale (Hyperoodon 
ampullatus), killer whale (Orcinus orca), pygmy killer whale (Feresa 
attenuata), false killer whale (Pseudorca crassidens), melon-headed 
whale (Peponocephala electra), Risso's dolphin (Grampus griseus), 
striped dolphin (Stenella coeruleoalba), Atlantic spotted dolphin 
(Stenella frontalis), white-beaked dolphin (Lagenorhynchus 
albirostris), pantropical spotted dolphin (Stenella attenuata), 
Fraser's dolphin (Lagenodelphis hosei), rough-toothed dolphin (Steno 
bredanensis), Clymene dolphin (Stenella clymene), spinner dolphin 
(Stenella longirostris), hooded seal (Cystophora cristata), ringed seal 
(Pusa hipsida), Cuvier's beaked whale (Ziphius cavirostris), four 
species of Mesoplodont beaked whale (Mesoplodon spp.), and the West 
Indian manatee (Trichechus manatus latirostris) (which occurs further 
south than the project area). These species are not analyzed further in 
this document.
    There are 13 marine mammal species that could potentially occur in 
the proposed project area and that are included in Table 10 of the IHA 
application. However, the temporal and/or spatial occurrence of three 
of the species listed in Table 10 of the IHA application is such that 
take of these species is not expected to occur, and they are therefore 
not discussed further beyond the explanation provided here. Take of 
these species is not anticipated either because they have very low 
densities in the project area, or because of their likely occurrence in 
habitat that is outside the project area, based on the best available 
information. The Atlantic white-sided dolphin (Lagenorhynchus acutus) 
occurs throughout temperate and sub-polar waters of the North Atlantic, 
most prominently in continental shelf waters to depths of approximately 
100 m (330 ft) (Hayes et al., 2018). Though recent survey data in 
unavailable, Atlantic white-sided dolphins were found primarily east 
and north of Long Island and the project area based on observations 
made during the Cetaceans and Turtle Assessment Program (CeTAP) surveys 
from 1978 to 1982 (CeTAP, 1982). The Atlantic white-sided dolphins 
observed south of Long Island were farther offshore in the deeper water 
of the continental shelf proper and closer to the continental shelf 
slope. There are two pilot whale species in the western North Atlantic: 
The long-finned pilot whale (Globicephala melas melas), and short-
finned pilot whale (Globicephala macrorhynchus). The latitudinal ranges 
of the two species remain uncertain, although south of Cape Hatteras, 
most pilot whale sightings are expected to be short-finned pilot 
whales, while north of ~42[deg] N most pilot whale sightings are 
expected to be long-finned pilot whales, and the two species overlap 
spatially along the mid-Atlantic shelf break between New Jersey and the 
southern flank of Georges Bank (Hayes et al., 2018). The available data 
suggests that long-finned pilot whales are more common along the 
continental shelf off the northeast coast of the United States during 
winter and early spring, and move into the more northerly waters of 
Georges Bank and the Gulf of Maine from late spring through autumn 
(CeTAP, 1982). Both species prefer deeper offshore waters compared to 
the relatively shallow waters of the project area, are not often 
observed in the waters overlying the continental shelf proper and are 
more commonly seen at the continental shelf break and farther offshore 
on the slope. As these species are not expected to occur in the project 
area during the proposed activities, they are not discussed further in 
this document.
    We expect that the species listed in Table 2 will potentially occur 
in the project area and will potentially be taken as a result of the 
proposed project. Table 2 summarizes information related to the 
population or stock, including regulatory status under the MMPA and ESA 
and potential biological removal (PBR), where known. For taxonomy, we 
follow Committee on Taxonomy (2018). PBR is defined by the MMPA as the 
maximum number of animals, not including natural mortalities, that may 
be removed from a marine mammal stock while allowing that stock to 
reach or maintain its optimum sustainable population (as described in 
NMFS' SARs). While no mortality is anticipated or authorized here, PBR 
is included here as a gross indicator of the status of the species and 
other threats.
    Marine mammal abundance estimates presented in this document 
represent the total number of individuals that make up a given stock or 
the total

[[Page 45960]]

number estimated within a particular study or survey area. NMFS' stock 
abundance estimates for most species represent the total estimate of 
individuals within the geographic area, if known, that comprises that 
stock. For some species, this geographic area may extend beyond U.S. 
waters. All managed stocks in this region are assessed in NMFS' U.S. 
Atlantic SARs. All values presented in Table 2 are the most recent 
available at the time of publication and are available in the 2017 
Atlantic SARs (Hayes et al., 2018) or draft 2018 SARs, available online 
at: www.fisheries.noaa.gov/action/2018-draft-marine-mammal-stock-assessment-reports-available.

                        Table 2--Marine Mammals Known To Occur in the Project Area That May Be Affected by the Proposed Activity
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                        MMPA and ESA     Stock abundance
                                                           status;       (CV, Nmin, most     Predicted abundance     PBR   Annual M/    Occurrence and
  Common name (scientific name)          Stock          strategic (Y/    recent abundance          (CV) \3\          \4\     SI \4\     seasonality in
                                                           N) \1\          survey) \2\                                                   project area
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                               Toothed whales (Odontoceti)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Bottlenose dolphin (Tursiops      W. North Atlantic,   -; N            77,532 (0.40;        \5\ 97,476 (0.06)....     561       39.4  Rare in summer;
 truncatus).                       Offshore.                            56,053; 2011).                                                 absent in winter.
                                  W. North Atlantic    -; N            6,639 (0.41; 4,759;                             48    unknown  Common year round.
                                   Coastal Migratory.                   2015).
Common dolphin \6\ (Delphinus     W. North Atlantic..  -; N            173,486 (0.55;       86,098 (0.12)........     557        406  Common year round.
 delphis).                                                              55,690; 2011).
Harbor porpoise (Phocoena         Gulf of Maine/Bay    -; N            79,833 (0.32;        * 45,089 (0.12)......     706        255  Common year round.
 phocoena).                        of Fundy.                            61,415; 2011).
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                Baleen whales (Mysticeti)
--------------------------------------------------------------------------------------------------------------------------------------------------------
North Atlantic right whale        W. North Atlantic..  E; Y            451 (0; 455; n/a)..  * 535 (0.45).........     0.9         56  Year round in
 (Eubalaena glacialis).                                                                                                                continental shelf
                                                                                                                                       and slope waters,
                                                                                                                                       occur seasonally.
Humpback whale \7\ (Megaptera     Gulf of Maine......  -; N            896 (0.42; 239; n/   * 1,637 (0.07).......    14.6        9.8  Common year round.
 novaeangliae).                                                         a).
Minke whale \6\ (Balaenoptera     Canadian East Coast  -; N            20,741 (0.3; 1,425;  * 2,112 (0.05).......      14        7.5  Year round in
 acutorostrata).                                                        n/a).                                                          continental shelf
                                                                                                                                       and slope waters,
                                                                                                                                       occur seasonally.
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                Earless seals (Phocidae)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Gray seal \8\ (Halichoerus        W. North Atlantic..  -; N            27,131 (0.10;        .....................   1,389      5,688  Common year round.
 grypus).                                                               25,908; n/a).
Harbor seal (Phoca vitulina)....  W. North Atlantic..  -; N            75,834 (0.15;        .....................   2,006        345  Common year round.
                                                                        66,884; 2012).
Harp seal (Pagophilus             W. North Atlantic..  -; N            7,411,000 (unk.;                               unk    225,687  Rare.
 groenlandicus).                                                        unk; 2014).
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ ESA status: Endangered (E), Threatened (T)/MMPA status: Depleted (D). A dash (-) indicates that the species is not listed under the ESA or
  designated as depleted under the MMPA. Under the MMPA, a strategic stock is one for which the level of direct human-caused mortality exceeds PBR (see
  footnote 3) or which is determined to be declining and likely to be listed under the ESA within the foreseeable future. Any species or stock listed
  under the ESA is automatically designated under the MMPA as depleted and as a strategic stock.
\2\ Stock abundance as reported in NMFS marine mammal stock assessment reports (SAR) except where otherwise noted. SARs available online at:
  www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments. CV is coefficient of variation; Nmin is the minimum estimate
  of stock abundance. In some cases, CV is not applicable. For certain stocks, abundance estimates are actual counts of animals and there is no
  associated CV. The most recent abundance survey that is reflected in the abundance estimate is presented; there may be more recent surveys that have
  not yet been incorporated into the estimate. All values presented here are from the 2018 draft Atlantic SARs.
\3\ This information represents species- or guild-specific abundance predicted by recent habitat-based cetacean density models (Roberts et al., 2016,
  2017, 2018). These models provide the best available scientific information regarding predicted density patterns of cetaceans in the U.S. Atlantic
  Ocean, and we provide the corresponding abundance predictions as a point of reference. Total abundance estimates were produced by computing the mean
  density of all pixels in the modeled area and multiplying by its area. For those species marked with an asterisk, the available information supported
  development of either two or four seasonal models; each model has an associated abundance prediction. Here, we report the maximum predicted abundance.
\4\ Potential biological removal, defined by the MMPA as the maximum number of animals, not including natural mortalities, that may be removed from a
  marine mammal stock while allowing that stock to reach or maintain its optimum sustainable population size (OSP). Annual M/SI, found in NMFS' SARs,
  represent annual levels of human-caused mortality plus serious injury from all sources combined (e.g., commercial fisheries, subsistence hunting, ship
  strike). Annual M/SI values often cannot be determined precisely and is in some cases presented as a minimum value. All M/SI values are as presented
  in the draft 2018 SARs.
\5\ Abundance estimates are in some cases reported for a guild or group of species when those species are difficult to differentiate at sea. Similarly,
  the habitat-based cetacean density models produced by Roberts et al. (2016) are based in part on available observational data which, in some cases, is
  limited to genus or guild in terms of taxonomic definition. Roberts et al. (2016) produced a density model for bottlenose dolphins that does not
  differentiate between offshore and coastal stocks.
\6\ Abundance as reported in the 2007 Canadian Trans-North Atlantic Sighting Survey (TNASS), which provided full coverage of the Atlantic Canadian coast
  (Lawson and Gosselin, 2009). Abundance estimates from TNASS were corrected for perception and availability bias, when possible. In general, where the
  TNASS survey effort provided superior coverage of a stock's range (as compared with NOAA shipboard survey effort), the resulting abundance estimate is
  considered more accurate than the current NMFS abundance estimate (derived from survey effort with inferior coverage of the stock range). NMFS stock
  abundance estimate for the common dolphin is 70,184. NMFS stock abundance estimate for the fin whale is 1,618. NMFS stock abundance estimate for the
  minke whale is 2,591.
\7\ 2018 U.S. Atlantic draft SAR for the Gulf of Maine feeding population lists a current abundance estimate of 896 individuals. However, we note that
  the estimate is defined on the basis of feeding location alone (i.e., Gulf of Maine) and is therefore likely an underestimate.
\8\ NMFS stock abundance estimate applies to U.S. population only, actual stock abundance is approximately 505,000.

    Two marine mammal species that are listed under the Endangered 
Species Act (ESA) may be present in the project area and may be taken 
incidental to the proposed activity: The North Atlantic right whale and 
fin whale.
    Below is a description of the species that have the highest 
likelihood of occurring in the project area and are thus expected to 
potentially be taken by the proposed activities. For the majority of 
species potentially present in the specific geographic region, NMFS has 
designated only a single generic stock

[[Page 45961]]

(e.g., ``western North Atlantic'') for management purposes. This 
includes the ``Canadian east coast'' stock of minke whales, which 
includes all minke whales found in U.S. waters is also a generic stock 
for management purposes. For humpback whales, NMFS defines stocks on 
the basis of feeding locations, i.e., Gulf of Maine. However, 
references to humpback whales in this document refer to any individuals 
of the species that are found in the specific geographic region. Any 
biologically important areas (BIAs) that overlap spatially with the 
project area are addressed in the species sections below.

North Atlantic Right Whale

    The North Atlantic right whale ranges from calving grounds in the 
southeastern United States to feeding grounds in New England waters and 
into Canadian waters (Hayes et al., 2018). Surveys have demonstrated 
the existence of seven areas where North Atlantic right whales 
congregate seasonally, including north and east of the proposed project 
area in Georges Bank, off Cape Cod, and in Massachusetts Bay (Hayes et 
al., 2018). In the late fall months (e.g., October), right whales are 
generally thought to depart from the feeding grounds in the North 
Atlantic and move south to their calving grounds off Georgia and 
Florida. However, recent research indicates our understanding of their 
movement patterns remains incomplete (Davis et al. 2017). A review of 
passive acoustic monitoring data from 2004 to 2014 throughout the 
western North Atlantic demonstrated nearly continuous year-round right 
whale presence across their entire habitat range (for at least some 
individuals), including in locations previously thought of as migratory 
corridors, suggesting that not all of the population undergoes a 
consistent annual migration (Davis et al. 2017). In recent years, right 
whales have been observed off Long Island during the summer, outside of 
the migration period (NEFSC, 2019). According to the NMFS Northeast 
Fisheries Science Center's (NEFSC) North Atlantic Right Whale Sighting 
Advisory System, 50 right whale observations were reported in the 
waters south of Long Island and north of New Jersey between May 2004 
and May 2019, with 6 observations in the project area (NEFSC, 2019). 
The project area is not a known feeding area for right whales and right 
whales are not expected to be foraging along the southern coast of Long 
Island, including the project area, as their main prey species are 
typically concentrated in offshore waters several miles seaward of the 
Project area, and right whale foraging behavior has never been 
documented near the coast of Long Island. Therefore, any right whales 
in the vicinity of the project area are expected to be transient, most 
likely migrating through the area.
    The western North Atlantic population demonstrated overall growth 
of 2.8 percent per year between 1990 to 2010, despite a decline in 1993 
and no growth between 1997 and 2000 (Pace et al. 2017). However, since 
2010 the population has been in decline, with a 99.99 percent 
probability of a decline of just under 1 percent per year (Pace et al. 
2017). Between 1990 and 2015, calving rates varied substantially, with 
low calving rates coinciding with all three periods of decline or no 
growth (Pace et al. 2017). On average, North Atlantic right whale 
calving rates are estimated to be roughly half that of southern right 
whales (Eubalaena australis) (Pace et al. 2017), which are increasing 
in abundance (NMFS 2015). In 2018, no new North Atlantic right whale 
calves were documented in their calving grounds; this represented the 
first time since annual NOAA aerial surveys began in 1989 that no new 
right whale calves were observed. Seven right whale calves were 
documented in 2019. The current best estimate of population abundance 
for the species is 411 individuals, based on data as of September 4, 
2018 (Pettis et al., 2018).
    Elevated North Atlantic right whale mortalities have occurred since 
June 7, 2017 along the U.S. and Canadian coast. A total of 27 confirmed 
dead stranded whales (19 in Canada; 8 in the United States) have been 
documented. This event has been declared an Unusual Mortality Event 
(UME), with human interactions, including entanglement in fixed fishing 
gear and vessel strikes, implicated in at least 13 of the mortalities 
thus far. More information is available online at: 
www.fisheries.noaa.gov/national/marine-life-distress/2017-2019-north-atlantic-right-whale-unusual-mortality-event.
    NMFS' regulations at 50 CFR 224.105 designated nearshore waters of 
the Mid-Atlantic Bight as Mid-Atlantic U.S. Seasonal Management Areas 
(SMA) for right whales in 2008. SMAs were developed to reduce the 
threat of collisions between ships and right whales around their 
migratory route and calving grounds. A portion of one SMA, which is 
associated with the port of New York and New Jersey, overlaps spatially 
with the easternmost part of the project area (see Figure 7 in the IHA 
application). The SMA that occurs off New York and New Jersey is active 
from November 1 through April 30 of each year.

Fin Whale

    Fin whales are common in waters of the U. S. Atlantic EEZ, 
principally from Cape Hatteras northward (Waring et al., 2016). Fin 
whales are present north of 35-degree latitude in every season and are 
broadly distributed throughout the western North Atlantic for most of 
the year, though densities vary seasonally (Waring et al., 2016). Fin 
whales are found in small groups of up to five individuals (Brueggeman 
et al., 1987). Fin whales have been observed in the waters off the 
eastern end of Long Island, but are more common in deeper waters and 
would not be expected to occur within Raritan Bay.

Humpback Whale

    Humpback whales are found worldwide in all oceans. Humpback whales 
were listed as endangered under the Endangered Species Conservation Act 
(ESCA) in June 1970. In 1973, the ESA replaced the ESCA, and humpbacks 
continued to be listed as endangered. NMFS recently evaluated the 
status of the species, and on September 8, 2016, NMFS divided the 
species into 14 distinct population segments (DPS), removed the current 
species-level listing, and in its place listed four DPSs as endangered 
and one DPS as threatened (81 FR 62259; September 8, 2016). The 
remaining nine DPSs were not listed. The West Indies DPS, which is not 
listed under the ESA, is the only DPS of humpback whale that is 
expected to occur in the project area.
    There have been anecdotal reports of increased sightings of live 
humpback whales in the project area (Hynes, 2016; Brown et al., 2018a). 
Between 2011 and 2016, there have been at least 46 humpback whale 
sightings within Lower New York Bay, Upper New York Bay, and Raritan 
Bay (Brown et al., 2018a). Most sightings occurred during the summer 
months (July to September), with no documented sightings in the winter 
(Brown et al., 2018). A total of 617 humpback whale sightings were 
reported within the New York Bight based on data collected from 2011-
2017 (Brown et al., 2018). During winter, the majority of humpback 
whales from North Atlantic feeding areas mate and calve in the West 
Indies, where spatial and genetic mixing among feeding groups occurs, 
though significant numbers of animals are found in mid- and high-
latitude regions at this time and some individuals have been sighted 
repeatedly within the same winter season, indicating that not all 
humpback

[[Page 45962]]

whales migrate south every winter (Hayes et al., 2018).
    Since January 2016, elevated humpback whale mortalities have 
occurred along the Atlantic coast from Maine to Florida. Partial or 
full necropsy examinations have been conducted on approximately half of 
the 99 known cases. Of the whales examined, about 50 percent had 
evidence of human interaction, either ship strike or entanglement. 
While a portion of the whales have shown evidence of pre-mortem vessel 
strike, this finding is not consistent across all whales examined and 
more research is needed. NOAA is consulting with researchers that are 
conducting studies on the humpback whale populations, and these efforts 
may provide information on changes in whale distribution and habitat 
use that could provide additional insight into how these vessel 
interactions occurred. Three previous UMEs involving humpback whales 
have occurred since 2000, in 2003, 2005, and 2006. More information is 
available at: www.fisheries.noaa.gov/national/marine-life-distress/2016-2019-humpback-whale-unusual-mortality-event-along-atlantic-coast.

Minke Whale

    Minke whales occur in temperate, tropical, and high-latitude 
waters. The Canadian East Coast stock can be found in the area from the 
western half of the Davis Strait (45[deg] W) to the Gulf of Mexico 
(Hayes et al., 2018). This species generally occupies waters less than 
100 m deep on the continental shelf. There appears to be a strong 
seasonal component to minke whale distribution (Hayes et al., 2018). 
During spring and summer, they appear to be widely distributed from 
just east of Montauk Point, Long Island, northeast to Nantucket Shoals, 
and north towards Stellwagen Bank and Jeffrey's Ledge (CeTAP, 1982). 
During the fall, their range is much smaller and their abundance is 
reduced throughout their range (CeTAP, 1982). During the winter, they 
are largely absent from the vicinity of the project area (Waring et 
al., 2012).
    Since January 2017, elevated minke whale mortalities have occurred 
along the Atlantic coast from Maine through South Carolina, with a 
total of 61 strandings recorded when this document was written. This 
event has been declared a UME. Full or partial necropsy examinations 
were conducted on more than 60 percent of the whales. Preliminary 
findings in several of the whales have shown evidence of human 
interactions or infectious disease, but these findings are not 
consistent across all of the whales examined, so more research is 
needed. More information is available at: www.fisheries.noaa.gov/national/marine-life-distress/2017-2019-minke-whale-unusual-mortality-event-along-atlantic-coast.

Common Dolphin

    The common dolphin is found world-wide in temperate to subtropical 
seas. In the North Atlantic, common dolphins are typically found over 
the continental shelf between the 100-m and 2,000-m isobaths and over 
prominent underwater topography and east to the mid-Atlantic Ridge 
(Hayes et al., 2018), but may be found in shallower shelf waters as 
well. Common dolphins occur primarily east and north of Long Island and 
may occur in the project area during all seasons (CeTAP, 1982). Between 
2011 and 2015, 68 common dolphins stranded in New York and 53 stranded 
in New Jersey (Hayes et al., 2018). During 2013, 23 common dolphins 
stranded along the Long Island coast (RFMRP 2014).

Bottlenose Dolphin

    There are two distinct bottlenose dolphin mophotypes in the western 
North Atlantic: The coastal and offshore forms (Hayes et al., 2018). 
The two mophotypes are genetically distinct based upon both 
mitochondrial and nuclear markers (Hoelzel et al. 1998; Rosel et al. 
2009). The offshore form is distributed primarily along the outer 
continental shelf and continental slope in waters greater than 40 m 
from Georges Bank to the Florida Keys (Hayes et al., 2018). The Western 
North Atlantic Northern Migratory Coastal stock occupies coastal waters 
from the shoreline to approximately the 20-m isobath between 
Assateague, Virginia, and Long Island, New York during warm water 
months. The stock migrates in late summer and fall and, during cold 
water months (best described by January and February), occupies coastal 
waters from approximately Cape Lookout, North Carolina, to the North 
Carolina/Virginia border (Garrison et al., 2017). Based on the known 
distribution of the Western North Atlantic Northern Migratory Coastal 
stock, this stock could potentially occur in the vicinity of the 
project during area during the the proposed project; however, Sandy 
Hook, NJ (southeast of Raritan Bay) represents the northern extent of 
the stock's range, and there have been no confirmed sightings of the 
stock within the project area itself (Hayes et al., 2018).

Harbor Porpoise

    Harbor porpoises occur from the coastline to deep waters (>1800 m; 
Westgate et al. 1998), although the majority of the population is found 
over the continental shelf in waters less than 150 m (Hayes et al., 
2018). In the project area, only the Gulf of Maine/Bay of Fundy stock 
of harbor porpoise may be present. This stock is found in U.S. and 
Canadian Atlantic waters and is concentrated in the northern Gulf of 
Maine and southern Bay of Fundy region, but their range extends to 
North Carolina, depending on the season (Hayes et al. 2018). In 2011, 
six sightings were recorded inside Long Island Sound with one sighting 
recorded just outside the Sound (NEFSC and SEFSC, 2011). Between 2011 
and 2015, 33 harbor porpoises stranded in New York and 17 stranded in 
New Jersey (Hayes et al., 2018).

Harbor Seal

    The harbor seal is found in all nearshore waters of the North 
Atlantic and North Pacific Oceans and adjoining seas above about 
30[deg] N (Burns, 2009). In the western North Atlantic, harbor seals 
are distributed from the eastern Canadian Arctic and Greenland south to 
southern New England and New York, and occasionally to the Carolinas 
(Hayes et al., 2018). Their presence in the region of the project area 
is seasonal, with increasing numbers from October to March and a peak 
in mid-March (Hoover et al., 2013), when adults, sub-adults, and 
juveniles are expected to migrate south from Maine. They return north 
to the coastal waters of Maine and Canada in late spring (Katona et 
al., 1993). The closest known haulout sites for harbor seals in the 
vicinity of the project area are located 2.9 km (1. 8 mi) southwest of 
the Ambrose Channel Crossing site (Sandy Hook Beach) and 16.1 km (10 
statute miles) east of the MP14.5 to MP16.5 site (Sandy Hook Beach), 
with additional haulout sites along the neighboring islands to the 
north (CRESLI, 2019). The Coastal Research and Education Society of 
Long Island (CRESLI) has monitored seal populations in the project area 
for over 15 years and continues to conduct behavioral and population 
studies of seals around Long Island, including regular observations at 
a major haulout site at Cupsogue Beach Park, located approximately 96.6 
km (60 mi) north of the project area on the eastern shore of Long 
Island. There are approximately 26 haulout locations around Long 
Island, and CRESLI has documented a total of 18,321 harbor seals during 
334 surveys since 2004 (CRESLI, 2019).
    Since July 2018, elevated numbers of harbor seal and gray seal 
mortalities have occurred across Maine, New Hampshire and 
Massachusetts. This

[[Page 45963]]

event has been declared a UME. Additionally, stranded seals have shown 
clinical signs as far south as Virginia, although not in elevated 
numbers, therefore the UME investigation now encompasses all seal 
strandings from Maine to Virginia. Lastly, ice seals (harp and hooded 
seals) have also started stranding with clinical signs, again not in 
elevated numbers, and those two seal species have also been added to 
the UME investigation. A total of 1,593 reported strandings (of all 
species) had occurred as of the writing of this document. Full or 
partial necropsy examinations have been conducted on some of the seals 
and samples have been collected for testing. Based on tests conducted 
thus far, the main pathogen found in the seals is phocine distemper 
virus. NMFS is performing additional testing to identify any other 
factors that may be involved in this UME. Information on this UME is 
available online at: www.fisheries.noaa.gov/new-england-mid-atlantic/marine-life-distress/2018-2019-pinniped-unusual-mortality-event-along.

Gray Seal

    There are three major populations of gray seals found in the world; 
eastern Canada (western North Atlantic stock), northwestern Europe and 
the Baltic Sea. Gray seals in the project area belong to the western 
North Atlantic stock. The range for this stock is from New Jersey to 
Labrador. Current population trends show that gray seal abundance is 
likely increasing in the U.S. Atlantic EEZ (Hayes et al., 2018). 
Although the rate of increase is unknown, surveys conducted since their 
arrival in the 1980s indicate a steady increase in abundance in both 
Maine and Massachusetts (Hayes et al., 2018). It is believed that 
recolonization by Canadian gray seals is the source of the U.S. 
population (Hayes et al., 2018). The closest known haulout sites for 
gray seals in the vicinity of the project area are located 2.9 km (1.8 
mi) southwest of the Ambrose Channel Crossing site (Sandy Hook Beach) 
and 16.1 km (10 mi) east of the MP14.5 to MP16.5 site (Sandy Hook 
Beach). Additional haulout sites are likely Little Gull Island in the 
Long Island Sound (CRESLI, 2019). Gray seals also haul out on Great 
Gull Island and Little Gull Island in eastern Long Island Sound 
(DiGiovanni et al., 2015).
    As described above, elevated seal mortalities, including gray 
seals, have occurred from Maine to Virginia since July 2018. This event 
has been declared a UME, with phocine distemper virus identified as the 
main pathogen found in the seals. NMFS is performing additional testing 
to identify any other factors that may be involved in this UME. 
Information on this UME is available online at: www.fisheries.noaa.gov/new-england-mid-atlantic/marine-life-distress/2018-2019-pinniped-unusual-mortality-event-along.

Harp Seal

    Harp seals are highly migratory and occur throughout much of the 
North Atlantic and Arctic Oceans (Hayes et al., 2018). Breeding occurs 
between late-February and April and adults then assemble on suitable 
pack ice to undergo the annual molt. The migration then continues north 
to Arctic summer feeding grounds. Harp seal occurrence in the project 
area is considered rare. However, since the early 1990s, numbers of 
sightings and strandings have been increasing off the east coast of the 
United States from Maine to New Jersey (Katona et al. 1993; Rubinstein 
1994; Stevick and Fernald 1998; McAlpine 1999; Lacoste and Stenson 
2000; Soulen et al. 2013). These extralimital appearances usually occur 
in January-May (Harris et al. 2002), when the western North Atlantic 
stock is at its most southern point of migration. Between 2011 and 
2015, 78 harp seals stranded (mortalities) in New York and 22 stranded 
(mortalities) in New Jersey (Hayes et al., 2018). During 2013, eight 
harp seals stranded (mortalities and alive) on Long Island (RFMRP, 
2014). All of those strandings occurred between January and June.
    As described above, elevated seal mortalities, including harp 
seals, have occurred across Maine, New Hampshire and Massachusetts, and 
as far south as Virginia, since July 2018. This event has been declared 
a UME, with phocine distemper virus identified as the main pathogen 
found in the seals. NMFS is performing additional testing to identify 
any other factors that may be involved in this UME. Information on this 
UME is available online at: www.fisheries.noaa.gov/new-england-mid-atlantic/marine-life-distress/2018-2019-pinniped-unusual-mortality-event-along.

Marine Mammal Hearing

    Hearing is the most important sensory modality for marine mammals 
underwater, and exposure to anthropogenic sound can have deleterious 
effects. To appropriately assess the potential effects of exposure to 
sound, it is necessary to understand the frequency ranges marine 
mammals are able to hear. Current data indicate that not all marine 
mammal species have equal hearing capabilities (e.g., Richardson et 
al., 1995; Wartzok and Ketten, 1999; Au and Hastings, 2008). To reflect 
this, Southall et al. (2007, 2019) recommended that marine mammals be 
divided into functional hearing groups based on directly measured or 
estimated hearing ranges on the basis of available behavioral response 
data, audiograms derived using auditory evoked potential techniques, 
anatomical modeling, and other data. Note that no direct measurements 
of hearing ability have been successfully completed for mysticetes 
(i.e., low-frequency cetaceans). Subsequently, NMFS (2018) described 
generalized hearing ranges for these marine mammal hearing groups. 
Generalized hearing ranges were chosen based on the approximately 65 
decibel (dB) threshold from the normalized composite audiograms, with 
the exception for lower limits for low-frequency cetaceans where the 
lower bound was deemed to be biologically implausible and the lower 
bound from Southall et al. (2007) retained. Marine mammal hearing 
groups and their associated hearing ranges are provided in Table 3.

           Table 3--Marine Mammal Hearing Groups (NMFS, 2018)
------------------------------------------------------------------------
               Hearing group                 Generalized hearing range *
------------------------------------------------------------------------
Low-frequency (LF) cetaceans (baleen         7 Hz to 35 kHz.
 whales).
Mid-frequency (MF) cetaceans (dolphins,      150 Hz to 160 kHz.
 toothed whales, beaked whales, bottlenose
 whales).
High-frequency (HF) cetaceans (true          275 Hz to 160 kHz.
 porpoises, Kogia, river dolphins,
 cephalorhynchid, Lagenorhynchus cruciger &
 L. australis).
Phocid pinnipeds (PW) (underwater) (true     50 Hz to 86 kHz.
 seals).

[[Page 45964]]

 
Otariid pinnipeds (OW) (underwater) (sea     60 Hz to 39 kHz.
 lions and fur seals).
------------------------------------------------------------------------
* Represents the generalized hearing range for the entire group as a
  composite (i.e., all species within the group), where individual
  species' hearing ranges are typically not as broad. Generalized
  hearing range chosen based on ~65 dB threshold from normalized
  composite audiogram, with the exception for lower limits for LF
  cetaceans (Southall et al. 2007) and PW pinniped (approximation).

    The pinniped functional hearing group was modified from Southall et 
al. (2007) on the basis of data indicating that phocid species have 
consistently demonstrated an extended frequency range of hearing 
compared to otariids, especially in the higher frequency range 
(Hemil[auml] et al., 2006; Kastelein et al., 2009; Reichmuth and Holt, 
2013).
    For more detail concerning these groups and associated frequency 
ranges, please see NMFS (2018) for a review of available information. 
Nine marine mammal species (six cetacean and three pinniped (all phocid 
species)) have the reasonable potential to co-occur with the proposed 
activities. Please refer to Table 2. Of the cetacean species that may 
be present, three are classified as low-frequency cetaceans (i.e., all 
mysticete species), two are classified as mid-frequency cetaceans 
(i.e., all delphinid species), and one is classified as a high-
frequency cetacean (i.e., harbor porpoise).

Potential Effects of Specified Activities on Marine Mammals and Their 
Habitat

    This section includes a summary and discussion of the ways that 
components of the specified activity may impact marine mammals and 
their habitat. The Estimated Take section later in this document 
includes a quantitative analysis of the number of individuals that are 
expected to be taken by this activity. The Negligible Impact Analysis 
and Determination section considers the content of this section, the 
Estimated Take section, and the Proposed Mitigation section, to draw 
conclusions regarding the likely impacts of these activities on the 
reproductive success or survivorship of individuals and how those 
impacts on individuals are likely to impact marine mammal species or 
stocks.

Description of Sound Sources

    This section contains a brief technical background on sound, on the 
characteristics of certain sound types, and on metrics used in this 
proposal inasmuch as the information is relevant to the specified 
activity and to a discussion of the potential effects of the specified 
activity on marine mammals found later in this document. For general 
information on sound and its interaction with the marine environment, 
please see, e.g., Au and Hastings (2008); Richardson et al. (1995); 
Urick (1983).
    Sound travels in waves, the basic components of which are 
frequency, wavelength, velocity, and amplitude. Frequency is the number 
of pressure waves that pass by a reference point per unit of time and 
is measured in hertz (Hz) or cycles per second. Wavelength is the 
distance between two peaks or corresponding points of a sound wave 
(length of one cycle). Higher frequency sounds have shorter wavelengths 
than lower frequency sounds, and typically attenuate (decrease) more 
rapidly, except in certain cases in shallower water. Amplitude is the 
height of the sound pressure wave or the ``loudness'' of a sound and is 
typically described using the relative unit of the decibel (dB). A 
sound pressure level (SPL) in dB is described as the ratio between a 
measured pressure and a reference pressure (for underwater sound, this 
is 1 microPascal ([mu]Pa)), and is a logarithmic unit that accounts for 
large variations in amplitude; therefore, a relatively small change in 
dB corresponds to large changes in sound pressure. The source level 
(SL) represents the SPL referenced at a distance of 1 m from the source 
(referenced to 1 [mu]Pa), while the received level is the SPL at the 
listener's position (referenced to 1 [mu]Pa).
    Root mean square (rms) is the quadratic mean sound pressure over 
the duration of an impulse. Root mean square is calculated by squaring 
all of the sound amplitudes, averaging the squares, and then taking the 
square root of the average (Urick, 1983). Root mean square accounts for 
both positive and negative values; squaring the pressures makes all 
values positive so that they may be accounted for in the summation of 
pressure levels (Hastings and Popper, 2005). This measurement is often 
used in the context of discussing behavioral effects, in part because 
behavioral effects, which often result from auditory cues, may be 
better expressed through averaged units than by peak pressures.
    Sound exposure level (SEL; represented as dB re 1 [mu]Pa\2\-s) 
represents the total energy in a stated frequency band over a stated 
time interval or event, and considers both intensity and duration of 
exposure. The per-pulse SEL is calculated over the time window 
containing the entire pulse (i.e., 100 percent of the acoustic energy). 
SEL is a cumulative metric; it can be accumulated over a single pulse, 
or calculated over periods containing multiple pulses. Cumulative SEL 
represents the total energy accumulated by a receiver over a defined 
time window or during an event. Peak sound pressure (also referred to 
as zero-to-peak sound pressure or 0-pk) is the maximum instantaneous 
sound pressure measurable in the water at a specified distance from the 
source, and is represented in the same units as the rms sound pressure.
    When underwater objects vibrate or activity occurs, sound-pressure 
waves are created. These waves alternately compress and decompress the 
water as the sound wave travels. Underwater sound waves radiate in a 
manner similar to ripples on the surface of a pond and may be either 
directed in a beam or beams or may radiate in all directions 
(omnidirectional sources), as is the case for sound produced by the 
pile driving activity considered here. The compressions and 
decompressions associated with sound waves are detected as changes in 
pressure by aquatic life and man-made sound receptors such as 
hydrophones.
    Even in the absence of sound from the specified activity, the 
underwater environment is typically loud due to ambient sound, which is 
defined as environmental background sound levels lacking a single 
source or point (Richardson et al., 1995). The sound level of a region 
is defined by the total acoustical energy being generated by known and 
unknown sources. These sources may include physical (e.g., wind and 
waves, earthquakes, ice, atmospheric sound), biological (e.g., sounds 
produced by marine mammals, fish, and invertebrates), and anthropogenic 
(e.g., vessels, dredging, construction) sound. A number of sources 
contribute to ambient sound, including wind and waves, which are a main 
source of naturally occurring ambient sound for frequencies between 200 
hertz (Hz) and 50 kilohertz (kHz) (Mitson, 1995). In general, ambient

[[Page 45965]]

sound levels tend to increase with increasing wind speed and wave 
height. Precipitation can become an important component of total sound 
at frequencies above 500 Hz, and possibly down to 100 Hz during quiet 
times. Marine mammals can contribute significantly to ambient sound 
levels, as can some fish and snapping shrimp. The frequency band for 
biological contributions is from approximately 12 Hz to over 100 kHz. 
Sources of ambient sound related to human activity include 
transportation (surface vessels), dredging and construction, oil and 
gas drilling and production, geophysical surveys, sonar, and 
explosions. Vessel noise typically dominates the total ambient sound 
for frequencies between 20 and 300 Hz. In general, the frequencies of 
anthropogenic sounds are below 1 kHz and, if higher frequency sound 
levels are created, they attenuate rapidly.
    The sum of the various natural and anthropogenic sound sources that 
comprise ambient sound at any given location and time depends not only 
on the source levels (as determined by current weather conditions and 
levels of biological and human activity) but also on the ability of 
sound to propagate through the environment. In turn, sound propagation 
is dependent on the spatially and temporally varying properties of the 
water column and sea floor, and is frequency-dependent. As a result of 
the dependence on a large number of varying factors, ambient sound 
levels can be expected to vary widely over both coarse and fine spatial 
and temporal scales. Sound levels at a given frequency and location can 
vary by 10-20 decibels (dB) from day to day (Richardson et al., 1995). 
The result is that, depending on the source type and its intensity, 
sound from the specified activity may be a negligible addition to the 
local environment or could form a distinctive signal that may affect 
marine mammals. Underwater ambient sound in Raritan Bay and the New 
York Bight is comprised of sounds produced by a number of natural and 
anthropogenic sources. Human-generated sound is a significant 
contributor to the ambient acoustic environment in the project 
location. Details of source types are described in the following text.
    Sounds are often considered to fall into one of two general types: 
Pulsed and non-pulsed (defined in the following). The distinction 
between these two sound types is important because they have differing 
potential to cause physical effects, particularly with regard to 
hearing (e.g., Ward, 1997 in Southall et al., 2007). Please see 
Southall et al. (2007) for an in-depth discussion of these concepts. 
The distinction between these two sound types is not always obvious, as 
certain signals share properties of both pulsed and non-pulsed sounds. 
A signal near a source could be categorized as a pulse, but due to 
propagation effects as it moves farther from the source, the signal 
duration becomes longer (e.g., Greene and Richardson, 1988).
    Pulsed sound sources (e.g., airguns, explosions, gunshots, sonic 
booms, impact pile driving) produce signals that are brief (typically 
considered to be less than one second), broadband, atonal transients 
(ANSI, 1986, 2005; Harris, 1998; NIOSH, 1998; ISO, 2003) and occur 
either as isolated events or repeated in some succession. Pulsed sounds 
are all characterized by a relatively rapid rise from ambient pressure 
to a maximal pressure value followed by a rapid decay period that may 
include a period of diminishing, oscillating maximal and minimal 
pressures, and generally have an increased capacity to induce physical 
injury as compared with sounds that lack these features.
    Non-pulsed sounds can be tonal, narrowband, or broadband, brief or 
prolonged, and may be either continuous or intermittent (ANSI, 1995; 
NIOSH, 1998). Some of these non-pulsed sounds can be transient signals 
of short duration but without the essential properties of pulses (e.g., 
rapid rise time). Examples of non-pulsed sounds include those produced 
by vessels, aircraft, machinery operations such as drilling or 
dredging, vibratory pile driving, and active sonar systems. The 
duration of such sounds, as received at a distance, can be greatly 
extended in a highly reverberant environment.
    The impulsive sound generated by impact hammers is characterized by 
rapid rise times and high peak levels. Vibratory hammers produce non-
impulsive, continuous noise at levels significantly lower than those 
produced by impact hammers. Rise time is slower, reducing the 
probability and severity of injury, and sound energy is distributed 
over a greater amount of time (e.g., Nedwell and Edwards, 2002; Carlson 
et al., 2005).

Acoustic Effects

    We previously provided general background information on marine 
mammal hearing (see ``Description of Marine Mammals in the Area of the 
Specified Activity''). Here, we discuss the potential effects of sound 
on marine mammals.
    Potential Effects of Underwater Sound--Note that, in the following 
discussion, we refer in many cases to a review article concerning 
studies of noise-induced hearing loss conducted from 1996-2015 (i.e., 
Finneran, 2015). For study-specific citations, please see that work. 
Anthropogenic sounds cover a broad range of frequencies and sound 
levels and can have a range of highly variable impacts on marine life, 
from none or minor to potentially severe responses, depending on 
received levels, duration of exposure, behavioral context, and various 
other factors. The potential effects of underwater sound from active 
acoustic sources can potentially result in one or more of the 
following: Temporary or permanent hearing impairment, non-auditory 
physical or physiological effects, behavioral disturbance, stress, and 
masking (Richardson et al., 1995; Gordon et al., 2004; Nowacek et al., 
2007; Southall et al., 2007; G[ouml]tz et al., 2009). The degree of 
effect is intrinsically related to the signal characteristics, received 
level, distance from the source, and duration of the sound exposure. In 
general, sudden, high level sounds can cause hearing loss, as can 
longer exposures to lower level sounds. Temporary or permanent loss of 
hearing will occur almost exclusively for noise within an animal's 
hearing range. We first describe specific manifestations of acoustic 
effects before providing discussion specific to pile driving.
    Richardson et al. (1995) described zones of increasing intensity of 
effect that might be expected to occur, in relation to distance from a 
source and assuming that the signal is within an animal's hearing 
range. First is the area within which the acoustic signal would be 
audible (potentially perceived) to the animal but not strong enough to 
elicit any overt behavioral or physiological response. The next zone 
corresponds with the area where the signal is audible to the animal and 
of sufficient intensity to elicit behavioral or physiological 
responsiveness. Third is a zone within which, for signals of high 
intensity, the received level is sufficient to potentially cause 
discomfort or tissue damage to auditory or other systems. Overlaying 
these zones to a certain extent is the area within which masking (i.e., 
when a sound interferes with or masks the ability of an animal to 
detect a signal of interest that is above the absolute hearing 
threshold) may occur; the masking zone may be highly variable in size.
    We describe the more severe effects (i.e., certain non-auditory 
physical or physiological effects) only briefly as we do not expect 
that there is a reasonable likelihood that pile driving may result in 
such effects (see below for further

[[Page 45966]]

discussion). Potential effects from impulsive sound sources can range 
in severity from effects such as behavioral disturbance or tactile 
perception to physical discomfort, slight injury of the internal organs 
and the auditory system, or mortality (Yelverton et al., 1973). Non-
auditory physiological effects or injuries that theoretically might 
occur in marine mammals exposed to high level underwater sound or as a 
secondary effect of extreme behavioral reactions (e.g., change in dive 
profile as a result of an avoidance reaction) caused by exposure to 
sound include neurological effects, bubble formation, resonance 
effects, and other types of organ or tissue damage (Cox et al., 2006; 
Southall et al., 2007; Zimmer and Tyack, 2007; Tal et al., 2015). The 
construction activities considered here do not involve the use of 
devices such as explosives or mid-frequency tactical sonar that are 
associated with these types of effects.
    Threshold Shift--Marine mammals exposed to high-intensity sound, or 
to lower-intensity sound for prolonged periods, can experience hearing 
threshold shift (TS), which is the loss of hearing sensitivity at 
certain frequency ranges (Finneran, 2015). TS can be permanent (PTS), 
in which case the loss of hearing sensitivity is not fully recoverable, 
or temporary (TTS), in which case the animal's hearing threshold would 
recover over time (Southall et al., 2007). Repeated sound exposure that 
leads to TTS could cause PTS. In severe cases of PTS, there can be 
total or partial deafness, while in most cases the animal has an 
impaired ability to hear sounds in specific frequency ranges (Kryter, 
1985).
    When PTS occurs, there is physical damage to the sound receptors in 
the ear (i.e., tissue damage), whereas TTS represents primarily tissue 
fatigue and is reversible (Southall et al., 2007). In addition, other 
investigators have suggested that TTS is within the normal bounds of 
physiological variability and tolerance and does not represent physical 
injury (e.g., Ward, 1997). Therefore, NMFS does not consider TTS to 
constitute auditory injury.
    Relationships between TTS and PTS thresholds have not been studied 
in marine mammals, and there is no PTS data for cetaceans, but such 
relationships are assumed to be similar to those in humans and other 
terrestrial mammals. PTS typically occurs at exposure levels at least 
several decibels above (a 40-dB threshold shift approximates PTS onset; 
e.g., Kryter et al., 1966; Miller, 1974) that inducing mild TTS (a 6-dB 
threshold shift approximates TTS onset; e.g., Southall et al. 2007). 
Based on data from terrestrial mammals, a precautionary assumption is 
that the PTS thresholds for impulse sounds (such as impact pile driving 
pulses as received close to the source) are at least 6 dB higher than 
the TTS threshold on a peak-pressure basis and PTS cumulative sound 
exposure level thresholds are 15 to 20 dB higher than TTS cumulative 
sound exposure level thresholds (Southall et al., 2007). Given the 
higher level of sound or longer exposure duration necessary to cause 
PTS as compared with TTS, it is considerably less likely that PTS could 
occur.
    TTS is the mildest form of hearing impairment that can occur during 
exposure to sound (Kryter, 1985). While experiencing TTS, the hearing 
threshold rises, and a sound must be at a higher level in order to be 
heard. In terrestrial and marine mammals, TTS can last from minutes or 
hours to days (in cases of strong TTS). In many cases, hearing 
sensitivity recovers rapidly after exposure to the sound ends. Few data 
on sound levels and durations necessary to elicit mild TTS have been 
obtained for marine mammals.
    Marine mammal hearing plays a critical role in communication with 
conspecifics, and interpretation of environmental cues for purposes 
such as predator avoidance and prey capture. Depending on the degree 
(elevation of threshold in dB), duration (i.e., recovery time), and 
frequency range of TTS, and the context in which it is experienced, TTS 
can have effects on marine mammals ranging from discountable to 
serious. For example, a marine mammal may be able to readily compensate 
for a brief, relatively small amount of TTS in a non-critical frequency 
range that occurs during a time where ambient noise is lower and there 
are not as many competing sounds present. Alternatively, a larger 
amount and longer duration of TTS sustained during time when 
communication is critical for successful mother/calf interactions could 
have more serious impacts.
    Currently, TTS data only exist for four species of cetaceans 
(bottlenose dolphin, beluga whale (Delphinapterus leucas), harbor 
porpoise, and Yangtze finless porpoise (Neophocoena asiaeorientalis)) 
and three species of pinnipeds (northern elephant seal (Mirounga 
angustirostris), harbor seal, and California sea lion (Zalophus 
californianus)) exposed to a limited number of sound sources (i.e., 
mostly tones and octave-band noise) in laboratory settings (Finneran, 
2015). TTS was not observed in trained spotted (Phoca largha) and 
ringed (Pusa hispida) seals exposed to impulsive noise at levels 
matching previous predictions of TTS onset (Reichmuth et al., 2016). In 
general, harbor seals and harbor porpoises have a lower TTS onset than 
other measured pinniped or cetacean species (Finneran, 2015). 
Additionally, the existing marine mammal TTS data come from a limited 
number of individuals within these species. There are no data available 
on noise-induced hearing loss for mysticetes. For summaries of data on 
TTS in marine mammals or for further discussion of TTS onset 
thresholds, please see Southall et al. (2007), Finneran and Jenkins 
(2012), Finneran (2015), and NMFS (2018).
    Behavioral Effects--Behavioral disturbance may include a variety of 
effects, including subtle changes in behavior (e.g., minor or brief 
avoidance of an area or changes in vocalizations), more conspicuous 
changes in similar behavioral activities, and more sustained and/or 
potentially severe reactions, such as displacement from or abandonment 
of high-quality habitat. Behavioral responses to sound are highly 
variable and context-specific and any reactions depend on numerous 
intrinsic and extrinsic factors (e.g., species, state of maturity, 
experience, current activity, reproductive state, auditory sensitivity, 
time of day), as well as the interplay between factors (e.g., 
Richardson et al., 1995; Wartzok et al., 2003; Southall et al., 2007; 
Weilgart, 2007; Archer et al., 2010). Behavioral reactions can vary not 
only among individuals but also within an individual, depending on 
previous experience with a sound source, context, and numerous other 
factors (Ellison et al., 2012), and can vary depending on 
characteristics associated with the sound source (e.g., whether it is 
moving or stationary, number of sources, distance from the source). 
Please see Appendices B-C of Southall et al. (2007) for a review of 
studies involving marine mammal behavioral responses to sound.
    Habituation can occur when an animal's response to a stimulus wanes 
with repeated exposure, usually in the absence of unpleasant associated 
events (Wartzok et al., 2003). Animals are most likely to habituate to 
sounds that are predictable and unvarying. It is important to note that 
habituation is appropriately considered as a ``progressive reduction in 
response to stimuli that are perceived as neither aversive nor 
beneficial,'' rather than as, more generally, moderation in response to 
human disturbance (Bejder et al., 2009). The opposite process is 
sensitization, when an unpleasant experience leads to subsequent

[[Page 45967]]

responses, often in the form of avoidance, at a lower level of 
exposure. As noted, behavioral state may affect the type of response. 
For example, animals that are resting may show greater behavioral 
change in response to disturbing sound levels than animals that are 
highly motivated to remain in an area for feeding (Richardson et al., 
1995; NRC, 2003; Wartzok et al., 2003). Controlled experiments with 
captive marine mammals have showed pronounced behavioral reactions, 
including avoidance of loud sound sources (Ridgway et al., 1997; 
Finneran et al., 2003). Observed responses of wild marine mammals to 
loud pulsed sound sources (typically airguns or acoustic harassment 
devices) have been varied but often consist of avoidance behavior or 
other behavioral changes suggesting discomfort (Morton and Symonds, 
2002; see also Richardson et al., 1995; Nowacek et al., 2007). However, 
many delphinids approach low-frequency airgun source vessels with no 
apparent discomfort or obvious behavioral change (e.g., Barkaszi et 
al., 2012), indicating the importance of frequency output in relation 
to the species' hearing sensitivity.
    Available studies show wide variation in response to underwater 
sound; therefore, it is difficult to predict specifically how any given 
sound in a particular instance might affect marine mammals perceiving 
the signal. If a marine mammal does react briefly to an underwater 
sound by changing its behavior or moving a small distance, the impacts 
of the change are unlikely to be significant to the individual, let 
alone the stock or population. However, if a sound source displaces 
marine mammals from an important feeding or breeding area for a 
prolonged period, impacts on individuals and populations could be 
significant (e.g., Lusseau and Bejder, 2007; Weilgart, 2007; NRC, 
2005). However, there are broad categories of potential response, which 
we describe in greater detail here, that include alteration of dive 
behavior, alteration of foraging behavior, effects to breathing, 
interference with or alteration of vocalization, avoidance, and flight.
    Changes in dive behavior can vary widely and may consist of 
increased or decreased dive times and surface intervals as well as 
changes in the rates of ascent and descent during a dive (e.g., Frankel 
and Clark, 2000; Costa et al., 2003; Ng and Leung, 2003; Nowacek et 
al.; 2004; Goldbogen et al., 2013a, 2013b). Variations in dive behavior 
may reflect interruptions in biologically significant activities (e.g., 
foraging) or they may be of little biological significance. The impact 
of an alteration to dive behavior resulting from an acoustic exposure 
depends on what the animal is doing at the time of the exposure and the 
type and magnitude of the response.
    Disruption of feeding behavior can be difficult to correlate with 
anthropogenic sound exposure, so it is usually inferred by observed 
displacement from known foraging areas, the appearance of secondary 
indicators (e.g., bubble nets or sediment plumes), or changes in dive 
behavior. As for other types of behavioral response, the frequency, 
duration, and temporal pattern of signal presentation, as well as 
differences in species sensitivity, are likely contributing factors to 
differences in response in any given circumstance (e.g., Croll et al., 
2001; Nowacek et al.; 2004; Madsen et al., 2006; Yazvenko et al., 
2007). A determination of whether foraging disruptions incur fitness 
consequences would require information on or estimates of the energetic 
requirements of the affected individuals and the relationship between 
prey availability, foraging effort and success, and the life history 
stage of the animal.
    Variations in respiration naturally vary with different behaviors 
and alterations to breathing rate as a function of acoustic exposure 
can be expected to co-occur with other behavioral reactions, such as a 
flight response or an alteration in diving. However, respiration rates 
in and of themselves may be representative of annoyance or an acute 
stress response. Various studies have shown that respiration rates may 
either be unaffected or could increase, depending on the species and 
signal characteristics, again highlighting the importance in 
understanding species differences in the tolerance of underwater noise 
when determining the potential for impacts resulting from anthropogenic 
sound exposure (e.g., Kastelein et al., 2001, 2005, 2006; Gailey et 
al., 2007; Gailey et al., 2016).
    Marine mammals vocalize for different purposes and across multiple 
modes, such as whistling, echolocation click production, calling, and 
singing. Changes in vocalization behavior in response to anthropogenic 
noise can occur for any of these modes and may result from a need to 
compete with an increase in background noise or may reflect increased 
vigilance or a startle response. For example, in the presence of 
potentially masking signals, humpback whales and killer whales have 
been observed to increase the length of their songs (Miller et al., 
2000; Fristrup et al., 2003; Foote et al., 2004), while right whales 
have been observed to shift the frequency content of their calls upward 
while reducing the rate of calling in areas of increased anthropogenic 
noise (Parks et al., 2007). In some cases, animals may cease sound 
production during production of aversive signals (Bowles et al., 1994).
    Avoidance is the displacement of an individual from an area or 
migration path as a result of the presence of a sound or other 
stressors, and is one of the most obvious manifestations of disturbance 
in marine mammals (Richardson et al., 1995). For example, gray whales 
are known to change direction--deflecting from customary migratory 
paths--in order to avoid noise from airgun surveys (Malme et al., 
1984). Avoidance may be short-term, with animals returning to the area 
once the noise has ceased (e.g., Bowles et al., 1994; Goold, 1996; 
Stone et al., 2000; Morton and Symonds, 2002; Gailey et al., 2007). 
Longer-term displacement is possible, however, which may lead to 
changes in abundance or distribution patterns of the affected species 
in the affected region if habituation to the presence of the sound does 
not occur (e.g., Blackwell et al., 2004; Bejder et al., 2006; Teilmann 
et al., 2006).
    A flight response is a dramatic change in normal movement to a 
directed and rapid movement away from the perceived location of a sound 
source. The flight response differs from other avoidance responses in 
the intensity of the response (e.g., directed movement, rate of 
travel). Relatively little information on flight responses of marine 
mammals to anthropogenic signals exist, although observations of flight 
responses to the presence of predators have occurred (Connor and 
Heithaus, 1996). The result of a flight response could range from 
brief, temporary exertion and displacement from the area where the 
signal provokes flight to, in extreme cases, marine mammal strandings 
(Evans and England, 2001). However, it should be noted that response to 
a perceived predator does not necessarily invoke flight (Ford and 
Reeves, 2008), and whether individuals are solitary or in groups may 
influence the response.
    Behavioral disturbance can also impact marine mammals in more 
subtle ways. Increased vigilance may result in costs related to 
diversion of focus and attention (i.e., when a response consists of 
increased vigilance, it may come at the cost of decreased attention to 
other critical behaviors such as foraging or resting). These effects 
have generally not been demonstrated for marine mammals, but studies 
involving fish and terrestrial animals have shown that increased 
vigilance may substantially

[[Page 45968]]

reduce feeding rates (e.g., Beauchamp and Livoreil, 1997; Fritz et al., 
2002; Purser and Radford, 2011). In addition, chronic disturbance can 
cause population declines through reduction of fitness (e.g., decline 
in body condition) and subsequent reduction in reproductive success, 
survival, or both (e.g., Harrington and Veitch, 1992; Daan et al., 
1996; Bradshaw et al., 1998). However, Ridgway et al. (2006) reported 
that increased vigilance in bottlenose dolphins exposed to sound over a 
five-day period did not cause any sleep deprivation or stress effects.
    Many animals perform vital functions, such as feeding, resting, 
traveling, and socializing, on a diel cycle (24-hour cycle). Disruption 
of such functions resulting from reactions to stressors such as sound 
exposure are more likely to be significant if they last more than one 
diel cycle or recur on subsequent days (Southall et al., 2007). 
Consequently, a behavioral response lasting less than one day and not 
recurring on subsequent days is not considered particularly severe 
unless it could directly affect reproduction or survival (Southall et 
al., 2007). Note that there is a difference between multi-day 
substantive behavioral reactions and multi-day anthropogenic 
activities. For example, just because an activity lasts for multiple 
days does not necessarily mean that individual animals are either 
exposed to activity-related stressors for multiple days or, further, 
exposed in a manner resulting in sustained multi-day substantive 
behavioral responses.
    Stress Responses--An animal's perception of a threat may be 
sufficient to trigger stress responses consisting of some combination 
of behavioral responses, autonomic nervous system responses, 
neuroendocrine responses, or immune responses (e.g., Seyle, 1950; 
Moberg, 2000). In many cases, an animal's first and sometimes most 
economical (in terms of energetic costs) response is behavioral 
avoidance of the potential stressor. Autonomic nervous system responses 
to stress typically involve changes in heart rate, blood pressure, and 
gastrointestinal activity. These responses have a relatively short 
duration and may or may not have a significant long-term effect on an 
animal's fitness.
    Neuroendocrine stress responses often involve the hypothalamus-
pituitary-adrenal system. Virtually all neuroendocrine functions that 
are affected by stress--including immune competence, reproduction, 
metabolism, and behavior--are regulated by pituitary hormones. Stress-
induced changes in the secretion of pituitary hormones have been 
implicated in failed reproduction, altered metabolism, reduced immune 
competence, and behavioral disturbance (e.g., Moberg, 1987; Blecha, 
2000). Increases in the circulation of glucocorticoids are also equated 
with stress (Romano et al., 2004).
    The primary distinction between stress (which is adaptive and does 
not normally place an animal at risk) and ``distress'' is the cost of 
the response. During a stress response, an animal uses glycogen stores 
that can be quickly replenished once the stress is alleviated. In such 
circumstances, the cost of the stress response would not pose serious 
fitness consequences. However, when an animal does not have sufficient 
energy reserves to satisfy the energetic costs of a stress response, 
energy resources must be diverted from other functions. This state of 
distress will last until the animal replenishes its energetic reserves 
sufficient to restore normal function.
    Relationships between these physiological mechanisms, animal 
behavior, and the costs of stress responses are well studied through 
controlled experiments and for both laboratory and free-ranging animals 
(e.g., Holberton et al., 1996; Hood et al., 1998; Jessop et al., 2003; 
Krausman et al., 2004; Lankford et al., 2005). Stress responses due to 
exposure to anthropogenic sounds or other stressors and their effects 
on marine mammals have also been reviewed (Fair and Becker, 2000; 
Romano et al., 2002b) and, more rarely, studied in wild populations 
(e.g., Romano et al., 2002a). For example, Rolland et al. (2012) found 
that noise reduction from reduced ship traffic in the Bay of Fundy was 
associated with decreased stress in North Atlantic right whales. These 
and other studies lead to a reasonable expectation that some marine 
mammals will experience physiological stress responses upon exposure to 
acoustic stressors and that it is possible that some of these would be 
classified as ``distress.'' In addition, any animal experiencing TTS 
would likely also experience stress responses (NRC, 2003).
    Auditory Masking--Sound can disrupt behavior through masking, or 
interfering with, an animal's ability to detect, recognize, or 
discriminate between acoustic signals of interest (e.g., those used for 
intraspecific communication and social interactions, prey detection, 
predator avoidance, navigation) (Richardson et al., 1995; Erbe et al., 
2016). Masking occurs when the receipt of a sound is interfered with by 
another coincident sound at similar frequencies and at similar or 
higher intensity, and may occur whether the sound is natural (e.g., 
snapping shrimp, wind, waves, precipitation) or anthropogenic (e.g., 
shipping, sonar, seismic exploration) in origin. The ability of a noise 
source to mask biologically important sounds depends on the 
characteristics of both the noise source and the signal of interest 
(e.g., signal-to-noise ratio, temporal variability, direction), in 
relation to each other and to an animal's hearing abilities (e.g., 
sensitivity, frequency range, critical ratios, frequency 
discrimination, directional discrimination, age or TTS hearing loss), 
and existing ambient noise and propagation conditions.
    Under certain circumstances, marine mammals experiencing 
significant masking could also be impaired from maximizing their 
performance fitness in survival and reproduction. Therefore, when the 
coincident (masking) sound is man-made, it may be considered harassment 
if disrupting behavioral patterns. It is important to distinguish TTS 
and PTS, which persist after the sound exposure, from masking, which 
occurs during the sound exposure. Because masking (without resulting in 
TS) is not associated with abnormal physiological function, it is not 
considered a physiological effect, but rather a potential behavioral 
effect.
    The frequency range of the potentially masking sound is important 
in determining any potential behavioral impacts. For example, low-
frequency signals may have less effect on high-frequency echolocation 
sounds produced by odontocetes but are more likely to affect detection 
of mysticete communication calls and other potentially important 
natural sounds such as those produced by surf and some prey species. 
The masking of communication signals by anthropogenic noise may be 
considered as a reduction in the communication space of animals (e.g., 
Clark et al., 2009) and may result in energetic or other costs as 
animals change their vocalization behavior (e.g., Miller et al., 2000; 
Foote et al., 2004; Parks et al., 2007; Di Iorio and Clark, 2009; Holt 
et al., 2009). Masking can be reduced in situations where the signal 
and noise come from different directions (Richardson et al., 1995), 
through amplitude modulation of the signal, or through other 
compensatory behaviors (Houser and Moore, 2014). Masking can be tested 
directly in captive species (e.g., Erbe, 2008), but in wild populations 
it must be either modeled or inferred from evidence of masking 
compensation. There are few studies addressing real-world masking 
sounds likely to be experienced by marine

[[Page 45969]]

mammals in the wild (e.g., Branstetter et al., 2013).
    Masking affects both senders and receivers of acoustic signals and 
can potentially have long-term chronic effects on marine mammals at the 
population level as well as at the individual level. Low-frequency 
ambient sound levels have increased by as much as 20 dB (more than 
three times in terms of SPL) in the world's ocean from pre-industrial 
periods, with most of the increase from distant commercial shipping 
(Hildebrand, 2009). All anthropogenic sound sources, but especially 
chronic and lower-frequency signals (e.g., from vessel traffic), 
contribute to elevated ambient sound levels, thus intensifying masking.
    Potential Effects of the Specified Activity--As described 
previously (see ``Description of Active Acoustic Sound Sources''), 
Transco proposes to conduct pile driving and pile removal. The effects 
of pile driving and removal on marine mammals are dependent on several 
factors, including the size, type, and depth of the animal; the depth, 
intensity, and duration of the pile driving sound; the depth of the 
water column; the substrate of the habitat; the distance between the 
pile and the animal; and the sound propagation properties of the 
environment.
    Noise generated by impact pile driving consists of regular, pulsed 
sounds of short duration. These pulsed sounds are typically high energy 
with fast rise times. Exposure to these sounds may result in harassment 
depending on proximity to the sound source and a variety of 
environmental and biological conditions (Dahl et al. 2015; Nedwell et 
al., 2007). Illingworth & Rodkin (2007) measured an unattenuated sound 
pressure within 10 m (33 ft) at a peak of 220 dB re 1 [mu]Pa for a 2.4 
m (96 in) steel pile driven by an impact hammer. Studies of underwater 
sound from pile driving finds that most of the acoustic energy is below 
one to two kHz, with broadband sound energy near the source (40 Hz to 
>40 kHz) and only low-frequency energy (<~400 Hz) at longer ranges 
(Bailey et al., 2010; Erbe, 2009; Illingworth & Rodkin, 2007). There is 
typically a decrease in sound pressure and an increase in pulse 
duration the greater the distance from the noise source (Bailey et al., 
2010). Maximum noise levels from pile driving usually occur during the 
last stage of driving each pile where the highest hammer energy levels 
are used (Betke, 2008).
    The onset of behavioral disturbance from anthropogenic sound 
depends on both external factors (characteristics of sound sources and 
their paths) and the specific characteristics of the receiving animals 
(hearing, motivation, experience, demography) and is difficult to 
predict (Southall et al., 2007). It is possible that the onset of pile 
driving could result in temporary, short-term changes in an animal's 
typical behavioral patterns and/or temporary avoidance of the affected 
area. These behavioral changes may include (Richardson et al., 1995): 
Changing durations of surfacing and dives, number of blows per 
surfacing, or moving direction and/or speed; reduced/increased vocal 
activities; changing/cessation of certain behavioral activities (such 
as socializing or feeding); visible startle response or aggressive 
behavior (such as tail/fluke slapping or jaw clapping); avoidance of 
areas where sound sources are located; and/or flight responses. The 
biological significance of many of these behavioral disturbances is 
difficult to predict, especially if the detected disturbances appear 
minor. However, the consequences of behavioral modification could be 
expected to be biologically significant if the change affects growth, 
survival, or reproduction. Significant behavioral modifications that 
could lead to effects on growth, survival, or reproduction, such as 
drastic changes in diving/surfacing patterns or significant habitat 
abandonment are considered extremely unlikely in the case of the 
proposed project, as it is expected that mitigation measures, including 
clearance zones and soft start (described in detail below, see 
``Proposed Mitigation Measures'') will minimize the potential for 
marine mammals to be exposed to sound levels that would result in more 
extreme behavioral responses. In addition, marine mammals in the 
project area are expected to avoid any area that would be ensonified at 
sound levels high enough for the potential to result in more severe 
acute behavioral responses, as the environment within Raritan Bay would 
allow marine mammals the ability to freely move to other areas of the 
Bay without restriction.
    In the case of pile driving, sound sources would be active for 
relatively short durations, with relation to potential for masking. The 
frequencies output by pile driving activity are lower than those used 
by most species expected to be regularly present for communication or 
foraging. Those species who would be more susceptible to masking at 
these frequencies (LF cetaceans) use the area only seasonally. We 
expect insignificant impacts from masking, and any masking event that 
could possibly rise to Level B harassment under the MMPA would occur 
concurrently within the zones of behavioral harassment already 
estimated for pile driving, and which have already been taken into 
account in the exposure analysis.

Anticipated Effects on Marine Mammal Habitat

    The proposed activities would not result in permanent impacts to 
habitats used directly by marine mammals, but may have potential short-
term impacts to food sources such as forage fish. The proposed 
activities could also affect acoustic habitat (see masking discussion 
above), but meaningful impacts are unlikely. There are no known 
foraging hotspots, or other ocean bottom structures of significant 
biological importance to marine mammals present in the project area. 
Therefore, the main impact issue associated with the proposed activity 
would be temporarily elevated sound levels and the associated direct 
effects on marine mammals, as discussed previously. The most likely 
impact to marine mammal habitat occurs from pile driving effects on 
likely marine mammal prey (e.g., fish). Impacts to the immediate 
substrate during installation of piles are anticipated, but these would 
be limited to minor, temporary suspension of sediments, which could 
impact water quality and visibility for a short amount of time, without 
any expected effects on individual marine mammals. Impacts to substrate 
are therefore not discussed further.
    Effects to Prey--Sound may affect marine mammals through impacts on 
the abundance, behavior, or distribution of prey species (e.g., 
crustaceans, cephalopods, fish, zooplankton). Marine mammal prey varies 
by species, season, and location and, for some, is not well documented. 
Here, we describe studies regarding the effects of noise on known 
marine mammal prey.
    Fish utilize the soundscape and components of sound in their 
environment to perform important functions such as foraging, predator 
avoidance, mating, and spawning (e.g., Zelick et al., 1999; Fay, 2009). 
Depending on their hearing anatomy and peripheral sensory structures, 
which vary among species, fishes hear sounds using pressure and 
particle motion sensitivity capabilities and detect the motion of 
surrounding water (Fay et al., 2008). The potential effects of noise on 
fishes depends on the overlapping frequency range, distance from the 
sound source, water depth of exposure, and species-specific hearing 
sensitivity, anatomy, and physiology. Key impacts to fishes may include 
behavioral responses, hearing damage,

[[Page 45970]]

barotrauma (pressure-related injuries), and mortality.
    Fish react to sounds which are especially strong and/or 
intermittent low-frequency sounds, and behavioral responses such as 
flight or avoidance are the most likely effects. Short duration, sharp 
sounds can cause overt or subtle changes in fish behavior and local 
distribution. The reaction of fish to noise depends on the 
physiological state of the fish, past exposures, motivation (e.g., 
feeding, spawning, migration), and other environmental factors. 
Hastings and Popper (2005) identified several studies that suggest fish 
may relocate to avoid certain areas of sound energy. Additional studies 
have documented effects of pile driving on fish, although several are 
based on studies in support of large, multiyear bridge construction 
projects (e.g., Scholik and Yan, 2001, 2002; Popper and Hastings, 
2009). Several studies have demonstrated that impulse sounds might 
affect the distribution and behavior of some fishes, potentially 
impacting foraging opportunities or increasing energetic costs (e.g., 
Fewtrell and McCauley, 2012; Pearson et al., 1992; Skalski et al., 
1992; Santulli et al., 1999; Paxton et al., 2017). However, some 
studies have shown no or slight reaction to impulse sounds (e.g., Pena 
et al., 2013; Wardle et al., 2001; Jorgenson and Gyselman, 2009; Cott 
et al., 2012). More commonly, though, the impacts of noise on fish are 
temporary.
    SPLs of sufficient strength have been known to cause injury to fish 
and fish mortality. However, in most fish species, hair cells in the 
ear continuously regenerate and loss of auditory function likely is 
restored when damaged cells are replaced with new cells. Halvorsen et 
al. (2012a) showed that a TTS of 4-6 dB was recoverable within 24 hours 
for one species. Impacts would be most severe when the individual fish 
is close to the source and when the duration of exposure is long. 
Injury caused by barotrauma can range from slight to severe and can 
cause death, and is most likely for fish with swim bladders. Barotrauma 
injuries have been documented during controlled exposure to impact pile 
driving (Halvorsen et al., 2012b; Casper et al., 2013).
    The most likely impact to fish from pile driving activities in the 
project area would be temporary behavioral avoidance of the area. The 
duration of fish avoidance of an area after pile driving stops is 
unknown, but a rapid return to normal recruitment, distribution and 
behavior is anticipated. In general, impacts to marine mammal prey 
species are expected to be minor and temporary due to the expected 
short daily duration of individual pile driving events and the 
relatively small areas being affected.
    The area likely impacted by the activities is relatively small 
compared to the available habitat in Raritan Bay. Any behavioral 
avoidance by fish of the disturbed area would still leave significantly 
large areas of fish and marine mammal foraging habitat in the nearby 
vicinity. Based on the information discussed herein, we conclude that 
impacts of the specified activity are not likely to have more than 
short-term adverse effects on any prey habitat or populations of prey 
species. Further, any impacts to marine mammal habitat are not expected 
to result in significant or long-term consequences for individual 
marine mammals, or to contribute to adverse impacts on their 
populations. Effects to habitat will not be discussed further in this 
document.

Estimated Take

    This section provides an estimate of the number of incidental takes 
proposed for authorization through this IHA, which will inform both 
NMFS' consideration of ``small numbers'' and the negligible impact 
determination.
    Harassment is the only type of take expected to result from these 
activities. Except with respect to certain activities not pertinent 
here, section 3(18) of 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).
    Authorized takes would primarily be by Level B harassment, as noise 
from pile driving has the potential to result in disruption of 
behavioral patterns for individual marine mammals. There is also some 
potential for auditory injury (Level A harassment) to result. The 
proposed mitigation and monitoring measures are expected to minimize 
the severity of such taking to the extent practicable. The proposed 
mitigation and monitoring measures are expected to minimize the 
severity of such taking to the extent practicable.
    As described previously, no mortality is anticipated or proposed to 
be authorized for this activity. Below we describe how the take is 
estimated.
    Generally speaking, we estimate take by considering: (1) Acoustic 
thresholds above which NMFS believes the best available science 
indicates marine mammals will be behaviorally harassed or incur some 
degree of permanent hearing impairment; (2) the area or volume of water 
that will be ensonified above these levels in a day; (3) the density or 
occurrence of marine mammals within these ensonified areas; and, (4) 
and the number of days of activities. We note that while these basic 
factors can contribute to a basic calculation to provide an initial 
prediction of takes, additional information that can qualitatively 
inform take estimates is also sometimes available (e.g., previous 
monitoring results or average group size). Below, we describe the 
factors considered here in more detail and present the proposed take 
estimate.

Acoustic Thresholds

    Using the best available science, NMFS has developed acoustic 
thresholds that identify the received level of underwater sound above 
which exposed marine mammals would be reasonably expected to be 
behaviorally harassed (equated to Level B harassment) or to incur PTS 
of some degree (equated to Level A harassment).
    Level B Harassment--Though significantly driven by received level, 
the onset of behavioral disturbance from anthropogenic noise exposure 
is also informed to varying degrees by other factors related to the 
source (e.g., frequency, predictability, duty cycle), the environment 
(e.g., bathymetry), and the receiving animals (hearing, motivation, 
experience, demography, behavioral context) and can be difficult to 
predict (Southall et al., 2007, Ellison et al., 2012). Based on what 
the available science indicates and the practical need to use a 
threshold based on a factor that is both predictable and measurable for 
most activities, NMFS uses a generalized acoustic threshold based on 
received level to estimate the onset of behavioral harassment. NMFS 
predicts that marine mammals are likely to be behaviorally harassed in 
a manner we consider Level B harassment when exposed to underwater 
anthropogenic noise above received levels of 160 dB re 1 [mu]Pa (rms) 
for impulsive and/or intermittent sources (e.g., impact pile driving) 
and 120 dB rms for continuous sources (e.g., vibratory driving). 
Transco's proposed activity includes the use of intermittent sources 
(impact pile driving) and continuous sources (vibratory driving), 
therefore use of the 120 and 160 dB re 1 [mu]Pa (rms) thresholds are 
applicable.
    Level A harassment--NMFS' Technical Guidance for Assessing the 
Effects of Anthropogenic Sound on

[[Page 45971]]

Marine Mammal Hearing (Version 2.0) (Technical Guidance, 2018) 
identifies dual criteria to assess auditory injury (Level A harassment) 
to five different marine mammal groups (based on hearing sensitivity) 
as a result of exposure to noise from two different types of sources 
(impulsive or non-impulsive). The components of Transco's proposed 
activity that may result in the take of marine mammals include the use 
of impulsive and non-impulsive sources.
    These thresholds are provided in Table 4 below. The references, 
analysis, and methodology used in the development of the thresholds are 
described in NMFS 2018 Technical Guidance, which may be accessed at: 
www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-acoustic-technical-guidance.

                     Table 4--Thresholds Identifying the Onset of Permanent Threshold Shift
----------------------------------------------------------------------------------------------------------------
                                                     PTS onset acoustic thresholds * (received level)
             Hearing group              ------------------------------------------------------------------------
                                                  Impulsive                         Non-impulsive
----------------------------------------------------------------------------------------------------------------
Low-Frequency (LF) Cetaceans...........  Cell 1: Lpk,flat: 219 dB;   Cell 2: LE,LF,24h: 199 dB.
                                          LE,LF,24h: 183 dB.
Mid-Frequency (MF) Cetaceans...........  Cell 3: Lpk,flat: 230 dB;   Cell 4: LE,MF,24h: 198 dB.
                                          LE,MF,24h: 185 dB.
High-Frequency (HF) Cetaceans..........  Cell 5: Lpk,flat: 202 dB;   Cell 6: LE,HF,24h: 173 dB.
                                          LE,HF,24h: 155 dB.
Phocid Pinnipeds (PW) (Underwater).....  Cell 7: Lpk,flat: 218 dB;   Cell 8: LE,PW,24h: 201 dB.
                                          LE,PW,24h: 185 dB.
Otariid Pinnipeds (OW) (Underwater)....  Cell 9: Lpk,flat: 232 dB;   Cell 10: LE,OW,24h: 219 dB.
                                          LE,OW,24h: 203 dB.
----------------------------------------------------------------------------------------------------------------
* Dual metric acoustic thresholds for impulsive sounds: Use whichever results in the largest isopleth for
  calculating PTS onset. If a non-impulsive sound has the potential of exceeding the peak sound pressure level
  thresholds associated with impulsive sounds, these thresholds should also be considered.
Note: Peak sound pressure (Lpk) has a reference value of 1 [micro]Pa, and cumulative sound exposure level (LE)
  has a reference value of 1[micro]Pa\2\s. In this Table, thresholds are abbreviated to reflect American
  National Standards Institute standards (ANSI 2013). However, peak sound pressure is defined by ANSI as
  incorporating frequency weighting, which is not the intent for this Technical Guidance. Hence, the subscript
  ``flat'' is being included to indicate peak sound pressure should be flat weighted or unweighted within the
  generalized hearing range. The subscript associated with cumulative sound exposure level thresholds indicates
  the designated marine mammal auditory weighting function (LF, MF, and HF cetaceans, and PW and OW pinnipeds)
  and that the recommended accumulation period is 24 hours. The cumulative sound exposure level thresholds could
  be exceeded in a multitude of ways (i.e., varying exposure levels and durations, duty cycle). When possible,
  it is valuable for action proponents to indicate the conditions under which these acoustic thresholds will be
  exceeded.

Ensonified Area

    Here, we describe operational and environmental parameters of the 
activity that will feed into identifying the area ensonified above the 
acoustic thresholds, which include source levels and transmission loss 
coefficient.
    Sound Propagation--Transmission loss (TL) is the decrease in 
acoustic intensity as an acoustic pressure wave propagates out from a 
source. TL parameters vary with frequency, temperature, sea conditions, 
current, source and receiver depth, water depth, water chemistry, and 
bottom composition and topography. The general formula for underwater 
TL is:

TL = B * log10(R1/R2),

Where

B = transmission loss coefficient (assumed to be 15)
R1 = the distance of the modeled SPL from the driven 
pile, and
R2 = the distance from the driven pile of the initial 
measurement.

    This formula neglects loss due to scattering and absorption, which 
is assumed to be zero here. The degree to which underwater sound 
propagates away from a sound source is dependent on a variety of 
factors, most notably the water bathymetry and presence or absence of 
reflective or absorptive conditions including in-water structures and 
sediments. Spherical spreading occurs in a perfectly unobstructed 
(free-field) environment not limited by depth or water surface, 
resulting in a 6 dB reduction in sound level for each doubling of 
distance from the source (20*log(range)). Cylindrical spreading occurs 
in an environment in which sound propagation is bounded by the water 
surface and sea bottom, resulting in a reduction of 3 dB in sound level 
for each doubling of distance from the source (10*log(range)). As is 
common practice in coastal waters, here we assume practical spreading 
loss (4.5 dB reduction in sound level for each doubling of distance). 
Practical spreading is a compromise that is often used under conditions 
where water depth increases as the receiver moves away from the 
shoreline, resulting in an expected propagation environment that would 
lie between spherical and cylindrical spreading loss conditions.
    Sound Source Levels--The intensity of pile driving sounds is 
greatly influenced by factors such as the type of piles, hammers, and 
the physical environment in which the activity takes place. Acoustic 
measurements of pile driving at the project area are not available. 
Therefore, to estimate sound levels associated with the proposed 
project, representative source levels for installation and removal of 
each pile type and size were identified using the compendium compiled 
by the California Department of Transportation (Caltrans, 2015). The 
information presented in Caltrans (2015) is a compilation of SPLs 
recorded during various in-water pile driving projects in California, 
Oregon, Washington, and Nebraska. The compendium is a commonly used 
reference document for pile driving source levels when analyzing 
potential impacts on protected species, including marine mammals, from 
pile driving activities.
    The proposed project would include impact and vibratory 
installation and vibratory removal of 0.25-m (10-in), 0.61-m (24-in), 
0.86-m (34-in), 0.91-m (36-in), 0.91- to 1.2-m (36- to 48-in), and 1.5-
m (60-in)-diameter steel pipe piles. Reference source levels from 
Caltrans (2015) were determined using data for piles of similar sizes, 
the same pile driving method as that proposed for the project, and at 
similar water depths (Table 5). While the pile sizes and water depths 
chosen as proxies do not exactly match those for the proposed project, 
they represent the closest matches available. It is assumed that the 
source levels shown in Table 5 are the most representative for each 
pile type and associated pile driving method. To be conservative, the 
representative sound source levels were based on the largest pile 
expected to be driven/removed at each potential in-water construction 
site. For example, where Transco may use a range of pile sizes (i.e., 
0.91 to 1.2 m (36 to 48 in)), the largest potential pile size (1.2 m 
(48 in)) was used in the modeling.

[[Page 45972]]



                          Table 5--Modeled Pile Installation and Removal Source Levels
----------------------------------------------------------------------------------------------------------------
                                                             RMS (dB)                          SEL
               Pile diameter (in)                ---------------------------------------------------------------
                                                      Impact         Vibratory        Impact         Vibratory
----------------------------------------------------------------------------------------------------------------
                                                  Installation
----------------------------------------------------------------------------------------------------------------
10..............................................  ..............             150  ..............             150
24..............................................  ..............             160  ..............             160
34..............................................             193             168             183             168
36..............................................             193             168             183             168
48..............................................  ..............             170  ..............             170
60..............................................             195             170             185             170
----------------------------------------------------------------------------------------------------------------
                                                     Removal
----------------------------------------------------------------------------------------------------------------
10..............................................  ..............             150  ..............             150
24..............................................  ..............             160  ..............             160
34..............................................  ..............             168  ..............             168
36..............................................  ..............             168  ..............             168
48..............................................  ..............             170  ..............             170
60..............................................  ..............             170  ..............             170
----------------------------------------------------------------------------------------------------------------

    Since there would be many piles at each of the construction sites 
within close proximately to one another, it was not practical to 
estimate zones of influence (ZOIs) for each individual pile, and 
results would have been nearly identical for all similarly sized piles 
at each construction location. In order to simplify calculations, a 
representative pile site was selected for eight separate pile locations 
(Table 6) (See Figure 8 in the IHA application for the representative 
locations).

        Table 6--Representative Pile Sites Selected for Modeling
------------------------------------------------------------------------
                                                             Pile size
                 Location/mile post (MP)                     (inches)
------------------------------------------------------------------------
HDD Morgan Offshore (MP 12.59)..........................              24
                                                                      36
                                                                      48
Neptune Power Cable Crossing (MP 13.84).................              10
MP 14.5 to MP 16.5......................................              24
MP 28.0 to MP 29.36.....................................              34
HDD Ambrose West Side (MP 29.4).........................              24
                                                                      36
                                                                      48
                                                                      60
HDD Ambrose East Side (MP 30.48)........................              24
                                                                      36
                                                                      48
                                                                      60
MP 34.5 to MP 35.04.....................................              34
Neptune Power Cable Crossing (MP 35.04).................              10
------------------------------------------------------------------------

    For strings where only a single pile type would be installed or 
removed (i.e., Neptune Power Cable Crossing MP13.84 and MP35.04, MP14.5 
to MP16.5, MP28.0 to MP29.36, and MP34.5 to MP35.04), the 
representative pile location was selected in the middle of the string. 
For the HDD Morgan Offshore string site, the location closest to the 
platform installation was selected as the representative pile location 
as it represents the area with the largest pile sizes. The HDD Ambrose 
West Side and HDD Ambrose East Side representative pile locations were 
selected based on the entry and exit pits. The HDD Ambrose East Side is 
the entry pit and the HDD Ambrose West Side is the exit pit. This would 
also represent the outer limit of the HDD Ambrose string, and is 
therefore the most conservative modeling option.
    Distances to isopleths associated with Level A and Level B 
harassment thresholds were calculated for each pile size, for vibratory 
and impact installation and removal activities, at the representative 
pile locations (Table 6). When the NMFS Technical Guidance (2016) was 
published, in recognition of the fact that ensonified area/volume could 
be more technically challenging to predict because of the duration 
component in the new thresholds, we developed a User Spreadsheet that 
includes tools to help predict a simple isopleth that can be used in 
conjunction with marine mammal density or occurrence to help predict 
takes. We note that because of some of the assumptions included in the 
methods used for these tools, we anticipate that isopleths produced are 
typically going to be overestimates of some degree, which may result in 
some degree of overestimate of Level A harassment take. However, these 
tools offer the best way to predict appropriate isopleths when more 
sophisticated 3D modeling methods are not available, and NMFS continues 
to develop ways to quantitatively refine these tools, and will 
qualitatively address the output where appropriate. For stationary 
sources such as pile driving from the proposed project the NMFS 
Optional User Spreadsheet predicts the closest distance at which, if a 
marine mammal remained at that distance the whole duration of the 
activity, it would incur PTS. Inputs used in the Optional User 
Spreadsheet, and the resulting isopleths, are reported below. The 
``Impact Pile Driving'' and ``Non-Impulse-stationary-continuous'' tabs 
of the Optional User Spreadsheet were used to calculate isopleth 
distances to the Level A harassment thresholds for impact and vibratory 
driving, respectively.
    The updated acoustic thresholds for impulsive sounds (such as pile 
driving) contained in the Technical Guidance (NMFS, 2018) were 
presented as dual metric acoustic thresholds using both 
SELcum and peak sound pressure level metrics. As dual 
metrics, NMFS considers onset of PTS (Level A harassment) to have 
occurred when either one of the two metrics is exceeded (i.e., metric 
resulting in the largest isopleth). The SELcum metric 
considers both level and duration of exposure, as well as auditory 
weighting functions by marine mammal hearing group. Isopleth distances 
to relevant Level A harassment thresholds were calculated, for both the 
SELcum and peak sound pressure level metrics, for all pile 
sizes at the representative pile driving locations as described above. 
The largest modeled isopleth distance to harassment thresholds based on 
the peak SPL metric was 34.1 m which was modeled based on 60 inch piles 
for the high frequency functional hearing group

[[Page 45973]]

(threshold of 202 dB re 1 [micro]Pa; Table 4). Calculation of isopleth 
distances to relevant Level A harassment thresholds for all pile sizes 
and all marine mammal functional hearing groups resulted in greater 
modeled distances associated with the SELcum metric than the 
peak sound pressure level metric, thus the modeled distances associated 
with the SELcum metric were carried forward in the exposure 
analysis to be conservative. It should be noted that this method likely 
results in a conservative estimate of Level A exposures because the 
SELcum metric assumes continuous exposure to the total 
duration of pile driving anticipated for a given day, which represents 
an unlikely scenario given that there is likely both some temporal and 
spatial separation between pile driving operations within a day (when 
multiple piles are driven), and that marine mammals are mobile and 
would be expected to move away from a sound source before it reached a 
level that would have the potential to result in auditory injury. 
Inputs to the Optional User Spreadsheet are shown in Tables 7 and 8. 
The resulting isopleth distances to Level A harassment thresholds are 
shown in Tables 9 and 10.

  Table 7--Inputs to NMFS Optional User Spreadsheet (NMFS, 2018) to Calculate Isopleth Distances to Level A Harassment Thresholds for Vibratory Driving
                                                                       and Removal
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                           Pile driving    Pile removal
                                                                             duration        duration        Weighting                      Distance of
        Pile size (representative pile location)           Source level   (hours) within  (hours) within      factor        Propagation    source level
                                                             (RMS SPL)       24- hour        24- hour       adjustment        (xLogR)       measurement
                                                                              period          period           (kHz)                            (m)
--------------------------------------------------------------------------------------------------------------------------------------------------------
10 in. (Neptune Power Cable Crossing MP 13.84)..........             150             1.0             1.0             2.5              15              10
10 in. (Neptune Power Cable Crossing MP 35.04)..........             150             0.5             0.5             2.5              15              10
24 in. (Ambrose East MP 30.48)..........................             160            1.25             5.5             2.5              15              10
24 in. (Ambrose West MP 29.4)...........................             160             1.5             0.5             2.5              15              10
24 in. (Morgan Offshore MP 12.59).......................             160             1.0             0.3             2.5              15              10
24 in. (MP 14.5)........................................             160            1.25            2.75             2.5              15              10
36 in. (Morgan Offshore MP 12.59).......................             168             1.0               4             2.5              15              10
36 in. (Ambrose East MP 30.48)..........................             168            0.75            0.75             2.5              15              10
36 in. (Ambrose West MP 29.4)...........................             168             0.5            0.75             2.5              15              10
48 in. (Ambrose East MP 30.48)..........................             170             2.0             2.0             2.5              15              10
48 in. (Ambrose West MP 29.4)...........................             170             1.0             2.0             2.5              15              10
48 in. (Morgan Offshore MP 12.59).......................             170             1.0            0.75             2.5              15              10
60 in. (Ambrose East MP 30.48)..........................             170            0.25            0.25             2.5              15              10
60 in. (Ambrose West MP 29.4)...........................             170             0.5             4.0             2.5              15              10
--------------------------------------------------------------------------------------------------------------------------------------------------------
Note: Tab A (``Non Impulsive Static Continuous'') in the NMFS Optional User Spreadsheet (NMFS, 2018) was used for all calculations for vibratory
  installation of piles.


   Table 8--Inputs to NMFS Optional User Spreadsheet (NMFS, 2018) To Calculate Isopleth Distances to Level A Harassment Thresholds for Impact Driving
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                             Weighting                      Distance of
                                                           Source level      Number of       Number of        factor        Propagation    source level
        Pile size (representative pile location)             (RMS SPL)      strikes per    piles per day    adjustment        (xLogR)       measurement
                                                                               pile                            (kHz)                            (m)
--------------------------------------------------------------------------------------------------------------------------------------------------------
36 in. (Morgan Offshore MP 12.59).......................             183           2,500           * 2/4               2              15              10
60 in. (Ambrose West....................................             185           3,382               2               2              15              10
--------------------------------------------------------------------------------------------------------------------------------------------------------
* The number of piles driven per day will vary based on the construction schedule, thus both scenarios (i.e., 2 and 4 piles driven per day) were
  modeled.
Note: Tab E1 (``Impact Pile Driving'') in the NMFS Optional User Spreadsheet (NMFS, 2018) was used for all calculations for impact pile driving.

    NMFS has established Level B harassment thresholds of 160 dB 
re1[mu]Pa (rms) for impulsive sounds (e.g., impact pile driving) and 
120 dB re1[mu]Pa (rms) for non-impulsive sounds (e.g., vibratory 
driving and removal). Based on the predicted source levels associated 
with various pile sizes (Table 5) the distances from the pile driving/
removal equipment to the Level B harassment thresholds were calculated, 
using the distance to the 160 dB threshold for the diesel impact hammer 
and the distance to the 120 dB threshold for the vibratory device, at 
the representative pile locations (Table 6). It should be noted that 
while sound levels associated with the Level B harassment threshold for 
vibratory driving/removal were estimated to propagate as far as 21,544 
m (13 mi) from pile installation and removal activities based on 
modeling, it is likely that the noise produced from vibratory 
activities associated with the project would be masked by background 
noise before reaching this distance, as the Port of New York and New 
Jersey, which represents the busiest port on the east coast of the 
United States and the third busiest port in the United States, is 
located near the project area and sounds from the port and from vessel 
traffic propagate throughout the project area. However, take estimates 
conservatively assume propagation of project-related noise to the full 
extent of the modeled isopleth distance to the Level B harassment 
threshold. The modeled distances to isopleths associated with Level B 
harassment thresholds for impact and vibratory driving are shown in 
Tables 9 and 10.

[[Page 45974]]



 Table 9--Modeled Isopleth Distances to Level A and Level B Harassment Thresholds for Impact and Vibratory Pile
                                                  Installation
----------------------------------------------------------------------------------------------------------------
                                                     Low-         Mid-        High-
                                                  frequency    frequency    frequency      Phocid     Cetaceans
                                                  cetaceans    cetaceans    cetaceans      seals     and phocids
----------------------------------------------------------------------------------------------------------------
Impulsive......................................       183 dB       185 dB       155 dB       185 dB       160 dB
Non-Impulsive..................................       199 dB       198 dB       173 dB       201 dB       120 dB
----------------------------------------------------------------------------------------------------------------


 
 
--------------------------------------------------------------------------------------------------------------------------------------------------------
Location/mile post                              Pile size  Hammer                          Distance to Level A harassment threshold (m) *    Distance to
(MP)                                             (inches)  type........................                                                          Level B
                                                                                                                                              harassment
                                                                                                                                               threshold
                                                                                                                                                     (m)
--------------------------------------------------------------------------------------------------------------------------------------------------------
HDD Morgan Offshore (MP 12.59)...........              24  Vibratory...................          5.9          0.5          8.7          3.6      4,641.6
                                                       36  Vibratory...................         20.0          1.8         29.6         12.2     15,848.9
                                                           Impact......................      4,635.2        164.9      5,521.3      2,480.6      1,584.9
                                                       48  Vibratory...................         27.2          2.4         40.2         16.5     21,544.3
Neptune Power Cable Crossing (MP 13.84)..              10  Vibratory...................          1.3          0.1          1.9          0.8      1,000.0
MP 14.5 to MP 16.5.......................              24  Vibratory...................          6.8          0.6         10.1          4.1      4,641.6
MP 28.0 to MP 29.36......................              34  Vibratory...................         20.0          1.8         29.6         12.2     15,848.9
HDD Ambrose West Side (MP 29.4)..........              24  Vibratory...................          7.7          0.7         11.3          4.7      4,641.6
                                                       36  Vibratory...................         12.6          1.1         18.6          7.7     15,848.9
                                                       48  Vibratory...................         27.2          2.4         40.2         16.5     21,544.3
                                                       60  Vibratory...................         17.1          1.5         25.3         10.4     21,544.3
                                                           Impact......................      4,855.2        172.7      5,783.3      2,598.3      2,154.4
HDD Ambrose East Side (MP 30.48).........              24  Vibratory...................          6.8          0.6         10.1          4.1      4,641.6
                                                       36  Vibratory...................         16.5          1.5         24.4         10.0     15,848.9
                                                       48  Vibratory...................         43.2          3.8         63.8         26.2     21,544.3
                                                       60  Vibratory...................         10.8          1.0         16.0          6.6     21,544.3
MP 34.5 to MP 35.04......................              34  Vibratory...................         12.6          1.1         18.6          7.7     15,848.9
                                                           Impact......................      2,920.0        103.9      3,478.2      1,562.7      1,584.9
Neptune Power Cable Crossing (MP 35.04)..              10  Vibratory...................          0.8          0.1          1.2          0.5      1,000.0
--------------------------------------------------------------------------------------------------------------------------------------------------------
* All distances shown are based on the SELcum metric. Distances to the peak SPL metric for impact driving were smaller than those for the SELcum metric
  for all pile sizes and scenarios.


  Table 10--Modeled Isopleth Distances to Level A and Level B Harassment Thresholds for Vibratory Pile Removal
----------------------------------------------------------------------------------------------------------------
                                                     Low-         Mid-        High-
                                                  frequency    frequency    frequency      Phocid     Cetaceans
                                                  cetaceans    cetaceans    cetaceans      seals     and phocids
----------------------------------------------------------------------------------------------------------------
Non-Impulsive..................................       199 dB       198 dB       173 dB       201 dB       120 dB
----------------------------------------------------------------------------------------------------------------


 
 
--------------------------------------------------------------------------------------------------------------------------------------------------------
Location/mile post                              Pile size  Hammer                           Distance to Level A harassment threshold (m)     Distance to
(MP)                                             (inches)  type........................                                                          Level B
                                                                                                                                              harassment
                                                                                                                                               threshold
                                                                                                                                                     (m)
--------------------------------------------------------------------------------------------------------------------------------------------------------
HDD Morgan Offshore (MP 12.59)...........              24  Vibratory...................          2.6          0.2          3.9          1.6      4,641.6
                                                       36  Vibratory...................         50.4          4.5         74.5         30.6     15,848.9
                                                       48  Vibratory...................         22.4          2.0         33.2         13.6     21,544.3
Neptune Power Cable Crossing (MP 13.84)..              10  Vibratory...................          1.3          0.1          1.9          0.8      1,000.0
MP 14.5 to MP 16.5.......................              24  Vibratory...................         11.5          1.0         17.0          7.0      4,641.6
MP 28.0 to MP 29.36......................              34  Vibratory...................         41.6          3.7         61.5         25.3     15,848.9
HDD Ambrose West Side (MP 29.4)..........              24  Vibratory...................          3.7          0.3          5.5          2.2      4,641.6
                                                       36  Vibratory...................         16.5          1.5         24.4         10.0     15,848.9
                                                       48  Vibratory...................         43.2          3.8         63.8         26.2     21,544.3
                                                       60  Vibratory...................         68.5          6.1        101.3         41.6     21,544.3
HDD Ambrose East Side (MP 30.48).........              24  Vibratory...................         18.3          1.6         27.0         11.1      4,641.6
                                                       36  Vibratory...................         16.5          1.5         24.4         10.0     15,848.9
                                                       48  Vibratory...................         43.2          3.8         63.8         26.2     21,544.3
                                                       60  Vibratory...................         10.8          1.0         16.0          6.6     21,544.3
MP 34.5 to MP 35.04......................              34  Vibratory...................         12.6          1.1         18.6          7.7     15,848.9
Neptune Power Cable Crossing (MP 35.04)..              10  Vibratory...................          0.8          0.1          1.2          0.5      1,000.0
--------------------------------------------------------------------------------------------------------------------------------------------------------


[[Page 45975]]

Marine Mammal Occurrence

    In this section we provide the information about the presence, 
density, or group dynamics of marine mammals that will inform the take 
calculations.
    There are no marine mammal density estimates for Raritan Bay. The 
best available information regarding marine mammal densities in the 
project area is provided by habitat-based density models produced by 
the Duke University Marine Geospatial Ecology Laboratory (Roberts et 
al., 2016, 2017, 2018). These density models were originally developed 
for all cetacean taxa in the U.S. Atlantic (Roberts et al., 2016); more 
information, including the model results and supplementary information 
for each model, is available at seamap.env.duke.edu/models/Duke-EC-GOM-2015/. In subsequent years, certain models have been updated on the 
basis of additional data as well as certain methodological 
improvements. Although these updated models (and a newly developed seal 
density model) are not currently publicly available, our evaluation of 
the changes leads to a conclusion that these represent the best 
scientific evidence available. Marine mammal density estimates in the 
project area (animals/km\2\) were obtained using these model results 
(Roberts et al., 2016, 2017, 2018). As noted, the updated models 
incorporate additional sighting data, including sightings from the NOAA 
Atlantic Marine Assessment Program for Protected Species (AMAPPS) 
surveys from 2010-2014 (NEFSC & SEFSC, 2011b, 2012, 2014a, 2014b, 2015, 
2016). For each cetacean species, density data for summer (June-August) 
and fall (September, October, November) were used to generate source 
grids by averaging monthly densities (see Figure 15 in the IHA 
application for an example of one such source grid). Since the source 
density grids do not extend to Raritan Bay, the grids were extrapolated 
to cover the bay and values were pulled from the nearest grid cell to 
assign density values to those empty cells in order to approximate 
densities in Raritan Bay (see Figure 16 in the IHA application). The 
resulting density grid was used to calculate take estimates of marine 
mammals for pile installation and removal activities. It should be 
noted that this approach likely results in conservative estimates of 
cetacean density for the project area, as cetacean densities in Raritan 
Bay are expected to be lower than the densities in the areas of the 
Atlantic Ocean from which the densities were extrapolated (with the 
exception of humpback whales, as described below).
    For harbor seals and gray seals, densities were first obtained from 
Roberts et al. (2018), as described above for cetacean densities. 
However, because the pinniped data used in the Roberts et al. (2018) 
density models were derived from offshore aerial and vessel surveys, 
the models did not accurately represent the densities of pinnipeds that 
would be expected in Raritan Bay, as they underestimate densities that 
would be expected closer to shore which would be higher than those 
offshore due to closer proximity to haulouts. Thus, the extrapolation 
of pinniped densities from Roberts et al. (2018) to Raritan Bay 
resulted in exposure estimates that were not consistent with 
expectations of actual pinniped densities based on the number of 
opportunistic sightings reported in the project area. There have been 
no systematic studies focusing on seal populations within Raritan Bay, 
Lower New York Bay, or Sandy Hook Bay. Therefore, pinniped densities 
were estimated using systematic data collected by Coastal Research and 
Education Society of Long Island, Inc. (CRESLI) from November 18, 2018, 
to April 16, 2019, at Cupsogue Beach Park in Westhampton Beach, NY 
(CRESLI, 2019).

Take Calculation and Estimation

    Here we describe how the information provided above is brought 
together to produce a quantitative take estimate. The following steps 
were performed to estimate the potential numbers of marine mammal 
exposures above Level A and Level B harassment thresholds as a result 
of the proposed activity:
    1. Distances to isopleths corresponding to Level A and Level B 
harassment thresholds were calculated for each pile size for vibratory 
and impact installation and removal activities at the representative 
pile locations within the Project area, as described above.
    2. GIS analysis was then used, incorporating these distance values 
and a viewshed analysis (described below), to calculate resulting ZOIs.
    3. Species density estimations were incorporated in the GIS 
analysis to determine estimated number of daily exposures.
    4. Daily exposure estimates were multiplied by the duration (days) 
of the corresponding in-water construction activity (based on pile size 
and location).
    As described above, the distances to isopleths associated with 
Level A and Level B harassment thresholds were calculated for each pile 
size for vibratory and impact installation and removal activities 
(Tables 9 and 10). These distances to relevant thresholds were then 
incorporated into a GIS analysis to analyze the relevant ZOIs within 
which take of marine mammals would be expected to occur. Given that the 
proposed activity would occur in a semi-enclosed bay, the modeled 
distances to thresholds would in some cases be truncated by land (i.e., 
the sounds from the proposed activity would not propagate to the full 
modeled isopleth distances because of the presence of land, which in 
some cases is closer to the pile driving/removal location than the 
total distances). A viewshed analysis is a standard technique used in 
GIS to determine whether an area is visible from a specific location 
(Kim et al., 2004). The analysis uses an elevation value of two points 
with direct line of sight to determine the likelihood of seeing the 
elevated point from the ground. Incorporating the viewshed analysis 
allowed GIS modeling of sound propagation to replicate how sound waves 
traveling through the water are truncated when they encounter land. GIS 
modeling used an artificial elevation model setting the water to zero 
(ground) and any land mass to 100 (elevated point) and focusing only on 
areas within the Project area where sound would propagate. Any land 
within direct `line of sight' to the sound source would prevent the 
sound from propagating farther. This method was applied to each of the 
eight representative pile locations. This simple model does not account 
for diffusion, which would be minimal with large landmasses; therefore 
in the model no sound bends around landmasses. See Figure 9 in the IHA 
application for an example of applying the viewshed analysis to a 
single representative pile location (HDD Morgan Offshore).
    A custom Python script was developed to calculate potential 
cetacean takes due to pile installation and removal activities. The 
script overlays the species-specific Level A and Level B harassment 
ZOIs (each clipped by the viewshed) for each pile size and type at each 
of the representative pile locations (Table 6), over the density grid 
cells. The script then multiplies the total density value by the area 
of the ZOI, resulting in initial take estimate outputs. The following 
formulas were implemented by the script for each species at each 
representative pile location:
Initial Level A take estimate = ZOI * d
Initial Level B take estimate = ZOI * d

Where:


[[Page 45976]]


ZOI = the ensonified area at or above the species-specific acoustic 
threshold, clipped by the viewshed.
d = density estimate for each species within the ZOI.

    The initial take estimates were then multiplied by the duration 
(days) of the corresponding in-water construction activity (based on 
pile size and location). The following formulas demonstrate this 
method:

Level A take estimate = initial take estimate * X days of activity
Level B take estimate = initial take estimate * X days of activity

Where:

X days of activity = number of days for which the corresponding in-
water construction activity occurs.

    These numbers were then totaled to provide estimates of the numbers 
of take by Level A and Level B harassment for each species. The 
exposure numbers were rounded to the nearest whole individual. As the 
construction schedule has not yet been finalized, the take calculations 
described above were performed for two scenarios: (1) All construction 
activities occurring during summer 2020, and (2) installation occurring 
during the summer and removal in fall of 2020. To be conservative, the 
higher take estimates calculated between the two scenarios were then 
carried forward in the analysis.
    Note that for bottlenose dolphins, the density data presented by 
Roberts et al. (2016) does not differentiate between bottlenose dolphin 
stocks. Thus, the take estimate for bottlenose dolphins calculated by 
the method described above resulted in an estimate of the total of 
bottlenose dolphins expected to be taken, from all stocks (for a total 
of 6,331 takes by Level B harassment). However, as described above, 
both the Western North Atlantic Northern Migratory Coastal stock and 
the Western North Atlantic Offshore stock have the potential to occur 
in the project area. As the project area represents the extreme 
northern extent of the known range of the Western North Atlantic 
Northern Migratory Coastal stock, and as dolphins from the Western 
North Atlantic Northern Migratory Coastal stock have never been 
documented in Raritan Bay, we assume that 25 percent of bottlenose 
dolphins taken would be from the North Atlantic Northern Migratory 
Coastal stock and the remaining 75 percent of bottlenose dolphins taken 
will be from the Western North Atlantic Offshore stock. Thus, we 
allocated 75 percent of the total proposed authorized bottlenose 
dolphin takes to the Western North Atlantic Offshore stock (total 4,748 
takes by Level B harassment), and 25 percent to the Western North 
Atlantic Northern Migratory Coastal stock (total 1,583 takes by Level B 
harassment) (Table 11).
    For humpback whales and harbor, gray and harp seals, the methods 
used to estimate take were slightly different than the methodology 
described above. For humpback whales, the steps above resulted in zero 
exposures above the Level B harassment threshold. However, there are 
confirmed anecdotal sightings of humpback whales within or near the 
project area, indicating that potential exposures above the Level B 
harassment threshold may occur and therefore should be accounted for. 
As the exposure estimate method described above resulted in zero 
exposures, other methods for calculating take by Level B harassment 
were applied. Brown et al. (2018) reported 617 sightings of humpback 
whales within the New York Bight from 2011 to 2017. The total number of 
sightings was divided by the total number of years of surveys (n=6), 
and this number was then divided by 12 months, to estimate a mean 
number of whales per month. This number was then multiplied by a 
conservative number of months of pile driving and removal activities 
(n=4) to estimate the number of humpback whales that may be taken Level 
B harassment (Table 11).
    As described above, local survey data represents the best available 
information on abundance estimates for pinnipeds in the project area. 
Estimates of take by Level B harassment for gray and harbor seals were 
calculated using systematic data collected by CRESLI from November 18, 
2018, to April 16, 2019, where a total of 2,689 harbor seals were 
sighted at Cupsogue Beach Park. The total number of sightings was 
divided by the total number of survey months (n=5) to get a mean number 
of individual seals per month. This number was then multiplied by a 
conservative number of potential months of pile driving and removal 
activities (n=4) to estimate a total number of seals (2,151) expected 
to be taken over the duration of the proposed project. To estimate the 
potential number of gray seals and harbor seals that may be taken, the 
ratio of harbor seals (64 percent) versus gray seals (36 percent) was 
calculated based on available density data. The data presented by 
Roberts et al. (2018 does not differentiate by seal species. Thus the 
best available density information on the ratio of gray to harbor seals 
comes from the U.S. Navy's OPAREA Density Estimates (Halpin et al. 
2009; Navy 2007, 2012). The ratio of gray to harbor seals in the OPAREA 
Density Estimates was therefore applied to the total number of seals 
estimated to be taken (n=2,151), to estimate the total number of gray 
and harbor seals expected to be taken during the duration of the 
proposed project. Based on this approach, we propose to authorize the 
incidental take of 1,377 harbor seals (2,151 * 0.64) and 774 gray seals 
(2,151 * 0.36).
    To calculate estimates of take by Level A harassment for gray and 
harbor seals, a ratio of take by Level A harassment relative to take by 
Level B harassment was calculated using the NODES data. These estimates 
accounted for the spatial extent of potential exposure to noise that 
could result in Level A and B harassment since they were based on the 
ensonifed areas multiplied by the NODES densities. Therefore, an 
estimation of the potential exposure of pinnipeds to Level A harassment 
as a proportion of potential exposure of pinnipeds to Level B 
harassment was used to calculate a reasonable estimate of Level A 
harassment takes using the Level B harassment estimates. This ratio was 
0.009 for harbor seals and 0.008 for gray seals; therefore, we propose 
to authorize the take by Level A harassment of 12 harbor seals (1,377 * 
0.009) and 6 gray seals (774 * 0.008).
    Due to lack of data and their rare occurrence in the Mid-Atlantic 
region, no densities for harp seals are available. However, harp seals 
have been documented along the southern coast of Long Island during the 
winter, and a recent pinniped UME has resulted in increased strandings 
of harp seals on the Atlantic coast. Because so few harp seals have 
been documented in the region of the project area, we estimate that up 
to four harp seals (the total number opportunistically observed at 
Cupsogue Beach (CRESLI, 2008) could enter the Level B harassment zone 
and be taken by Level B harassment. Take numbers proposed for 
authorization are shown in Table 11.

[[Page 45977]]



 Table 11--Total Numbers of Potential Incidental Takes of Marine Mammals Proposed for Authorization and Proposed
                                       Takes as a Percentage of Population
----------------------------------------------------------------------------------------------------------------
                                                                                                    Total takes
                                                  Takes by Level  Takes by Level                   proposed for
                                                   A harassment    B harassment     Total takes    authorization
                     Species                       proposed for    proposed for    proposed for        as a
                                                   authorization   authorization   authorization   percentage of
                                                                                                   stock taken *
----------------------------------------------------------------------------------------------------------------
Fin whale.......................................               0               5               5             0.1
Humpback Whale..................................               0              34              34             2.1
Minke Whale.....................................               0               1               1             0.0
North Atlantic Right Whale......................               0               2               2             0.5
Bottlenose Dolphin--Western North Atlantic                     0           1,583           1,583            23.8
 Northern Migratory Coastal stock...............
Bottlenose Dolphin--Western North Atlantic                     0           4,748           4,748             6.1
 Offshore stock.................................
Common Dolphin..................................               0              95              95             0.1
Harbor porpoise.................................               0              11              11             0.0
Gray seal.......................................               6             774             780             2.9
Harbor seal.....................................              12           1,377           1,389             1.8
Harp seal.......................................               0               4               4             0.0
----------------------------------------------------------------------------------------------------------------
* Calculations of percentage of stock taken are based on the best available abundance estimate as shown in Table
  2. For North Atlantic right whales the best available abundance estimate is derived from the 2018 North
  Atlantic Right Whale Consortium 2018 Annual Report Card (Pettis et al., 2018). For the pinniped species the
  best available abundance estimates are derived from the most recent NMFS Stock Assessment Reports. For all
  other species, the best available abundance estimates are derived from Roberts et al. (2016, 2017, 2018).

    The take numbers we propose for authorization are considered 
conservative for the following reasons:
     Density estimates assume are largely derived from adjacent 
grid-cells that likely overestimate density in the vicinity of the 
project area.
     Proposed Level A harassment take numbers do not account 
for the likelihood that marine mammals will avoid a stimulus when 
possible before that stimulus reaches a level that would have the 
potential to result in injury; and
     Proposed Level A harassment take numbers do not account 
for the effectiveness of proposed mitigation and monitoring measures in 
reducing the number of takes.

Proposed Mitigation

    In order to issue an IHA 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 on 
the availability of such species or stock for taking for certain 
subsistence uses (latter not applicable for this action). NMFS 
regulations require applicants for incidental take authorizations to 
include information about the availability and feasibility (economic 
and technological) of equipment, methods, and manner of conducting such 
activity or other means of effecting the least practicable adverse 
impact upon the affected species or stocks and their habitat (50 CFR 
216.104(a)(11)).
    In evaluating how mitigation may or may not be appropriate to 
ensure the least practicable adverse impact on species or stocks and 
their habitat, as well as subsistence uses where applicable, we 
carefully consider two primary factors:
    (1) The manner in which, and the degree to which, the successful 
implementation of the measure(s) is expected to reduce impacts to 
marine mammals, marine mammal species or stocks, and their habitat. 
This considers the nature of the potential adverse impact being 
mitigated (likelihood, scope, range). It further considers the 
likelihood that the measure will be effective if implemented 
(probability of accomplishing the mitigating result if implemented as 
planned), the likelihood of effective implementation (probability 
implemented as planned), and;
    (2) The practicability of the measures for applicant 
implementation, which may consider such things as cost and impact on 
operations.
    The mitigation strategies described below are consistent with those 
required and successfully implemented under previous incidental take 
authorizations issued in association with in-water construction 
activities. Modeling was performed to estimate zones of influence (ZOI; 
see ``Estimated Take''); these ZOI values were used to inform 
mitigation measures for pile driving activities to minimize Level A 
harassment and Level B harassment to the extent possible, while 
providing estimates of the areas within which Level B harassment might 
occur.
    In addition to the specific measures described later in this 
section, Transco would conduct briefings for construction supervisors 
and crews, the marine mammal monitoring teams, and Transco staff prior 
to the start of all pile driving activity, and when new personnel join 
the work, in order to explain responsibilities, communication 
procedures, the marine mammal monitoring protocol, and operational 
procedures.

Pre-Clearance Zones

    Transco would use Protected Species Observers (PSOs) to establish 
pre-clearance zones around the pile driving equipment to ensure these 
zones are clear of marine mammals prior to the start of pile driving. 
The purpose of ``clearance'' of a particular zone is to prevent 
potential instances of auditory injury and potential instances of more 
severe behavioral disturbance as a result of exposure to pile driving 
noise (serious injury or death are unlikely outcomes even in the 
absence of mitigation measures) by delaying the activity before it 
begins if marine mammals are detected within certain pre-defined 
distances of the pile driving equipment. The primary goal in this case 
is to prevent auditory injury (Level A harassment), and the proposed 
pre-clearance zones are larger than the modeled distances to the 
isopleths corresponding to Level A harassment (based on peak SPL) for 
all marine mammal functional hearing groups. These zones vary depending 
on species and are shown in Table 12. All

[[Page 45978]]

distances to pre-clearance zones are the radius from the center of the 
pile being driven.

 Table 12--Proposed Pre-Clearance Zones During Transco Pile Driving and
                           Removal Activities
------------------------------------------------------------------------
                  Species                          Clearance zone
------------------------------------------------------------------------
North Atlantic right whale................  Any distance.
Fin and humpback whale....................  1,000 m.
All other marine mammal species...........  100 m.
------------------------------------------------------------------------

    If a marine mammal is observed approaching or entering the relevant 
pre-clearance zones prior to the start of pile driving operations, pile 
driving activity would be delayed until either the marine mammal has 
voluntarily left the respective clearance zone and been visually 
confirmed beyond that zone, or, 30 minutes have elapsed without re-
detection of the animal.
    Prior to the start of pile driving activity, the pre-clearance 
zones will be monitored for 30 minutes to ensure that they are clear of 
the relevant species of marine mammals. Pile driving would only 
commence once PSOs have declared the respective pre-clearance zones 
clear of marine mammals. Marine mammals observed within a pre-clearance 
zone will be allowed to remain in the pre-clearance zone (i.e., must 
leave of their own volition), and their behavior will be monitored and 
documented. The pre-clearance zones (to a distance of 1,000 m) may only 
be declared clear, and pile driving started, when the entire pre-
clearance zones are visible (i.e., when not obscured by dark, rain, 
fog, etc.) for a full 30 minutes prior to pile driving.

Soft Start

    The use of a soft start procedure is believed to provide additional 
protection to marine mammals by warning marine mammals or providing 
them with a chance to leave the area prior to the hammer operating at 
full capacity, and typically involves a requirement to initiate sound 
from the hammer at reduced energy followed by a waiting period. Transco 
will utilize soft start techniques for impact pile driving by 
performing an initial set of three strikes from the impact hammer at a 
reduced energy level followed by a thirty second waiting period. The 
soft start process would be conducted a total of three times prior to 
driving each pile (e.g., three strikes followed by a thirty second 
delay, then three additional single strikes followed by a thirty second 
delay, then a final set of three strikes followed by an additional 
thirty second delay). Soft start would be required at the beginning of 
each day's impact pile driving work and at any time following a 
cessation of impact pile driving of thirty minutes or longer.

Shutdown

    The purpose of a shutdown is to prevent some undesirable outcome, 
such as auditory injury or behavioral disturbance of sensitive species, 
by halting the activity. If a marine mammal is observed entering or 
within the shutdown zones after pile driving has begun, the PSO will 
request a temporary cessation of pile driving. Transco has proposed 
that, when called for by a PSO, shutdown of pile driving would be 
implemented when feasible. However, if a shutdown is called for before 
a pile has been driven to a sufficient depth to allow for pile 
stability, then for safety reasons the pile would need to be driven to 
a sufficient depth to allow for stability and a shutdown would not be 
feasible until after that depth was reached. We therefore propose that 
shutdown would be implemented when feasible. If shutdown is called for 
by a PSO, and Transco determines a shutdown to be technically feasible, 
pile driving would be halted immediately. After shutdown, pile driving 
may be initiated once all clearance zones are clear of marine mammals 
for the minimum species-specific time periods, or, if required to 
maintain installation feasibility. For North Atlantic right whales, 
shutdown would occur when a right whale is observed by PSOs at any 
distance, and a shutdown zone of 85 m (279 ft) would be implemented for 
all other species (Table 13). The 500 m zone is proposed as a 
protective measure to avoid takes by Level A harassment, and 
potentially some takes by Level B harassment, of North Atlantic right 
whales. The 85 m zone was calculated based on the distance to the Level 
A harassment threshold based on the peak sound pressure metric (202 dB 
re 1[micro] Pa) for a 66-inch steel pile, plus an additional 50 m (164-
ft) buffer.

    Table 13--Proposed Shutdown Zones During Transco Pile Driving and
                           Removal Activities
------------------------------------------------------------------------
                  Species                           Shutdown zone
------------------------------------------------------------------------
North Atlantic right whale................  Any distance.
All other marine mammal species...........  85 m.
------------------------------------------------------------------------

Visibility Requirements

    All in-water construction and removal activities would be conducted 
during daylight hours, no earlier than 30 minutes after sunrise and no 
later than 30 minutes before sunset. Pile driving would not be 
initiated at night, or, when the full extent of all relevant clearance 
zones cannot be confirmed to be clear of marine mammals, as determined 
by the lead PSO on duty. The clearance zones may only be declared 
clear, and pile driving started, when the full extent of all clearance 
zones are visible (i.e., when not obscured by dark, rain, fog, etc.) 
for a full 30 minutes prior to pile driving.

Monitoring Protocols

    Monitoring would be conducted before, during, and after pile 
driving activities. In addition, observers will record all incidents of 
marine mammal occurrence, regardless of distance from the construction 
activity, and monitors will document any behavioral reactions in 
concert with distance from piles being driven. Observations made 
outside the shutdown zones will not result in delay of pile driving; 
that pile segment may be completed without cessation, unless the marine 
mammal approaches or enters the shutdown zone, at which point pile 
driving activities would be halted when practicable, as described 
above. Pile driving activities include the time to install a single 
pile or series of piles, as long as the time elapsed between uses of 
the pile driving equipment is no more than 30 minutes.
    The following additional measures apply to visual monitoring:
    (1) A minimum of two PSOs would be on duty at all times during pile 
driving and removal activity;
    (2) Monitoring would be conducted by qualified, trained PSOs. One 
PSO would be stationed on the construction barge and one on an escort 
boat, during impact and vibratory pile installation and removal. The 
escort boat location would shift depending on work location, but will 
be a minimum of 100 to 200 m (328 to 656 ft) from the pile-driving 
location, depending on the site and the ensonification area associated 
with that specific pile-driving scenario;
    (3) PSOs may not exceed four consecutive watch hours; must have a 
minimum two-hour break between watches; and may not exceed a combined 
watch schedule of more than 12 hours in a 24-hour period;
    (4) Monitoring will be conducted from 30 minutes prior to 
commencement of pile driving, throughout the time required to drive a 
pile, and for 30 minutes following the conclusion of pile driving;

[[Page 45979]]

    (5) PSOs will have no other construction-related tasks while 
conducting monitoring; and
    (6) PSOs would have the following minimum qualifications:
     Visual acuity in both eyes (correction is permissible) 
sufficient for discernment of moving targets at the water's surface 
with ability to estimate target size and distance; use of binoculars 
may be necessary to correctly identify the target;
     Ability to conduct field observations and collect data 
according to assigned protocols;
     Experience or training in the field identification of 
marine mammals, including the identification of behaviors;
     Sufficient training, orientation, or experience with the 
construction operation to provide for personal safety during 
observations;
     Writing skills sufficient to document observations 
including, but not limited to: The number and species of marine mammals 
observed; dates and times when in-water construction activities were 
conducted; dates and times when in-water construction activities were 
suspended to avoid potential incidental injury of marine mammals from 
construction noise within a defined shutdown zone; and marine mammal 
behavior; and
     Ability to communicate orally, by radio or in person, with 
project personnel to provide real-time information on marine mammals 
observed in the area as necessary.
    PSOs employed by Transco in satisfaction of the mitigation and 
monitoring requirements described herein must meet the following 
additional requirements:
     Independent observers (i.e., not construction personnel) 
are required;
     At least one observer must have prior experience working 
as an observer;
     Other observers may substitute education (degree in 
biological science or related field) or training for experience;
     One observer will be designated as lead observer or 
monitoring coordinator. The lead observer must have prior experience 
working as an observer; and
     NMFS will require submission and approval of observer CVs.

Vessel Strike Avoidance

    Vessel strike avoidance measures will include, but are not limited 
to, the following, except under circumstances when complying with these 
measures would put the safety of the vessel or crew at risk:
     All vessel operators and crew must maintain vigilant watch 
for cetaceans and pinnipeds, and slow down or stop their vessel to 
avoid striking these protected species;
     All vessels must travel at 10 knots (18.5 km/hr) or less 
within any designated Dynamic Management Area (DMA) for North Atlantic 
right whales;
     All vessels greater than or equal to 65 ft (19.8 m) in 
overall length will comply with 10 knot (18.5 km/hr) or less speed 
restriction in any Seasonal Management Area (SMA) for North Atlantic 
right whales per the NOAA ship strike reduction rule (73 FR 60173; 
October 10, 2008);
     All vessel operators will reduce vessel speed to 10 knots 
(18.5 km/hr) or less when any large whale, any mother/calf pairs, pods, 
or large assemblages of non-delphinoid cetaceans are observed near 
(within 100 m (330 ft)) an underway vessel;
     All survey vessels will maintain a separation distance of 
500 m (1640 ft) or greater from any sighted North Atlantic right whale;
     If underway, vessels must steer a course away from any 
sighted North Atlantic right whale at 10 knots (18.5 km/hr) or less 
until the 500 m (1640 ft) minimum separation distance has been 
established. If a North Atlantic right whale is sighted in a vessel's 
path, or within 500 m (330 ft) to an underway vessel, the underway 
vessel must reduce speed and shift the engine to neutral. Engines will 
not be engaged until the right whale has moved outside of the vessel's 
path and beyond 500 m. If stationary, the vessel must not engage 
engines until the North Atlantic right whale has moved beyond 500 m;
     All vessels will maintain a separation distance of 100 m 
(330 ft) or greater from any sighted non-delphinoid cetacean. If 
sighted, the vessel underway must reduce speed and shift the engine to 
neutral, and must not engage the engines until the non-delphinoid 
cetacean has moved outside of the vessel's path and beyond 100 m. If a 
vessel is stationary, the vessel will not engage engines until the non-
delphinoid cetacean has moved out of the vessel's path and beyond 100 
m;
     All vessels will maintain a separation distance of 50 m 
(164 ft) or greater from any sighted delphinoid cetacean, with the 
exception of delphinoid cetaceans that voluntarily approach the vessel 
(i.e., bow ride). Any vessel underway must remain parallel to a sighted 
delphinoid cetacean's course whenever possible, and avoid excessive 
speed or abrupt changes in direction. Any vessel underway must reduce 
vessel speed to 10 knots (18.5 km/hr) or less when pods (including 
mother/calf pairs) or large assemblages of delphinoid cetaceans are 
observed. Vessels may not adjust course and speed until the delphinoid 
cetaceans have moved beyond 50 m and/or the abeam of the underway 
vessel;
     All vessels will maintain a separation distance of 50 m 
(164 ft) or greater from any sighted pinniped; and
     All vessels underway will not divert or alter course in 
order to approach any whale, delphinoid cetacean, or pinniped. Any 
vessel underway will avoid excessive speed or abrupt changes in 
direction to avoid injury to the sighted cetacean or pinniped.
    Transco will ensure that vessel operators and crew maintain a 
vigilant watch for marine mammals by slowing down or stopping the 
vessel to avoid striking marine mammals. Project-specific training will 
be conducted for all vessel crew prior to the start of the construction 
activities. Confirmation of the training and understanding of the 
requirements will be documented on a training course log sheet.
    We have carefully evaluated Transco's proposed mitigation measures 
and considered a range of other measures in the context of ensuring 
that we prescribed the means of effecting the least practicable adverse 
impact on the affected marine mammal species and stocks and their 
habitat. Based on our evaluation of these measures, we have 
preliminarily determined that the proposed mitigation measures provide 
the means of effecting the least practicable adverse impact on marine 
mammal species or stocks and their habitat, paying particular attention 
to rookeries, mating grounds, and areas of similar significance, and on 
the availability of such species or stock for subsistence uses.

Proposed Monitoring and Reporting

    In order to issue an IHA 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 
authorizations 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 
proposed action area. Effective reporting is critical both to 
compliance as well as ensuring that the most value is obtained from the 
required monitoring.
    Monitoring and reporting requirements prescribed by NMFS

[[Page 45980]]

should contribute to improved understanding of one or more of the 
following:
     Occurrence of marine mammal species or stocks in the area 
in which take is anticipated (e.g., presence, abundance, distribution, 
density);
     Nature, scope, or context of likely marine mammal exposure 
to potential stressors/impacts (individual or cumulative, acute or 
chronic), through better understanding of: (1) Action or environment 
(e.g., source characterization, propagation, ambient noise); (2) 
affected species (e.g., life history, dive patterns); (3) co-occurrence 
of marine mammal species with the action; or (4) biological or 
behavioral context of exposure (e.g., age, calving or feeding areas);
     Individual marine mammal responses (behavioral or 
physiological) to acoustic stressors (acute, chronic, or cumulative), 
other stressors, or cumulative impacts from multiple stressors;
     How anticipated responses to stressors impact either: (1) 
Long-term fitness and survival of individual marine mammals; or (2) 
populations, species, or stocks;
     Effects on marine mammal habitat (e.g., marine mammal prey 
species, acoustic habitat, or other important physical components of 
marine mammal habitat); and
     Mitigation and monitoring effectiveness.

Visual Marine Mammal Observations

    Transco will collect sighting data and behavioral responses to pile 
driving activity for marine mammal species observed in the region of 
activity during the period of activity. All observers will be trained 
in marine mammal identification and behaviors and are required to have 
no other construction-related tasks while conducting monitoring. PSOs 
would monitor all clearance zones at all times. PSOs would also monitor 
Level B harassment zones and would document any marine mammals observed 
within these zones, to the extent practicable (noting that some 
distances to these zones are too large to fully observe). Transco would 
conduct monitoring before, during, and after pile driving and removal, 
with observers located at the best practicable vantage points.
    Transco would implement the following monitoring procedures:
     A minimum of two PSOs will maintain watch at all times 
when pile driving or removal is underway;
     PSOs would be located at the best possible vantage 
point(s) to ensure that they are able to observe the entire clearance 
zones and as much of the Level B harassment zone as possible;
     During all observation periods, PSOs will use binoculars 
and the naked eye to search continuously for marine mammals;
     If the clearance zones are obscured by fog or poor 
lighting conditions, pile driving will not be initiated until clearance 
zones are fully visible. Should such conditions arise while impact 
driving is underway, the activity would be halted when practicable, as 
described above; and
     The clearance zones will be monitored for the presence of 
marine mammals before, during, and after all pile driving activity.
    Individuals implementing the monitoring protocol will assess its 
effectiveness using an adaptive approach. PSOs will use their best 
professional judgment throughout implementation and seek improvements 
to these methods when deemed appropriate. Any modifications to the 
protocol will be coordinated between NMFS and Transco.

Data Collection

    We require that observers use standardized data forms. Among other 
pieces of information, Transco will record detailed information about 
any implementation of delays or shutdowns, including the distance of 
animals to the pile and a description of specific actions that ensued 
and resulting behavior of the animal, if any. We require that, at a 
minimum, the following information be collected on the sighting forms:
     Date and time that monitored activity begins or ends;
     Construction activities occurring during each observation 
period;
     Weather parameters (e.g., wind speed, percent cloud cover, 
visibility);
     Water conditions (e.g., sea state, tide state);
     Species, numbers, and, if possible, sex and age class of 
marine mammals;
     Description of any observable marine mammal behavior 
patterns, including bearing and direction of travel and distance from 
pile driving activity;
     Distance from pile driving activities to marine mammals 
and distance from the marine mammals to the observation point;
     Type of construction activity (e.g., impact or vibratory 
driving/removal) when marine mammals are observed.
     Description of implementation of mitigation measures 
(e.g., delay or shutdown).
     Locations of all marine mammal observations; and
     Other human activity in the area.
    Transco would note behavioral observations, to the extent 
practicable, if an animal has remained in the area during construction 
activities.

Reporting

    A draft report would be submitted to NMFS within 90 days of the 
completion of monitoring for each installation's in-water work window. 
The report would include marine mammal observations pre-activity, 
during-activity, and post-activity during pile driving days, and would 
also provide descriptions of any behavioral responses to construction 
activities by marine mammals. The report would detail the monitoring 
protocol, summarize the data recorded during monitoring including an 
estimate of the number of marine mammals that may have been harassed 
during the period of the report, and describe any mitigation actions 
taken (i.e., delays or shutdowns due to detections of marine mammals, 
and documentation of when shutdowns were called for but not implemented 
and why). A final report must be submitted within 30 days following 
resolution of comments on the draft report.

Negligible Impact Analysis and Determination

    NMFS has defined negligible impact 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 (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 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 harassment, NMFS considers other factors, such as the 
likely nature of any responses (e.g., intensity, duration), the context 
of any responses (e.g., critical reproductive time or location, 
migration), as well as effects on habitat, and the likely effectiveness 
of the mitigation. We also assess the number, intensity, and context of 
estimated takes by evaluating this information relative to population 
status. Consistent with the 1989 preamble for NMFS's implementing 
regulations (54 FR 40338; September 29, 1989), the impacts from other 
past and ongoing anthropogenic activities are incorporated into this 
analysis via their impacts on the environmental baseline (e.g., as 
reflected in the regulatory status of the species, population size and 
growth rate where known, ongoing

[[Page 45981]]

sources of human-caused mortality, or ambient noise levels).
    Pile driving and removal activities associated with the proposed 
project, as described previously, have the potential to disturb or 
temporarily displace marine mammals. Specifically, the specified 
activities may result in take, in the form of Level A harassment 
(potential injury) or Level B harassment (potential behavioral 
disturbance) from underwater sounds generated from pile driving and 
removal. Potential takes could occur if individual marine mammals are 
present in the ensonified zone when pile driving and removal is 
occurring. To avoid repetition, the our analyses apply to all the 
species listed in Table 1, given that the anticipated effects of the 
proposed project on different marine mammal species and stocks are 
expected to be similar in nature.
    Impact pile driving has source characteristics (short, sharp pulses 
with higher peak levels and sharper rise time to reach those peaks) 
that are potentially injurious or more likely to produce severe 
behavioral reactions. However, modeling indicates there is limited 
potential for injury even in the absence of the proposed mitigation 
measures, with most species predicted to experience no Level A 
harassment based on modeling results. In addition, the potential for 
injury is expected to be greatly minimized through implementation of 
the proposed mitigation measures including soft start and the 
implementation of clearance zones that would facilitate a delay of pile 
driving if marine mammals were observed approaching or within areas 
that could be ensonified above sound levels that could result in 
auditory injury. Given sufficient notice through use of soft start, 
marine mammals are expected to move away from a sound source that is 
annoying prior to its becoming potentially injurious or resulting in 
more severe behavioral reactions.
    We expect that any exposures above the Level A harassment threshold 
would be in the form of slight PTS, i.e. minor degradation of hearing 
capabilities within regions of hearing that align most completely with 
the energy produced by pile driving (i.e. the low-frequency region 
below 2 kHz), not severe hearing impairment. If hearing impairment 
occurs, it is most likely that the affected animal would lose a few 
decibels in its hearing sensitivity, which in most cases is not likely 
to meaningfully affect its ability to forage and communicate with 
conspecifics. However, given sufficient notice through use of soft 
start, marine mammals are expected to move away from a sound source 
that is annoying prior to its becoming potentially injurious or 
resulting in more severe behavioral reactions.
    Additionally, the numbers of exposures above the Level A harassment 
proposed for authorization are very low for all marine mammal stocks 
and species: For 9 of 11 stocks, we propose to authorize no takes by 
Level A harassment; for the remaining two stocks we propose to 
authorize no more than 12 takes by Level A harassment. As described 
above, we expect that marine mammals would be likely to move away from 
a sound source that represents an aversive stimulus, especially at 
levels that would be expected to result in PTS, given sufficient notice 
through use of soft start, thereby minimizing the degree of PTS that 
would be incurred. No serious injury or mortality of any marine mammal 
stocks are anticipated or proposed for authorization. Serious injury or 
mortality as a result of the proposed activities would not be expected 
even in the absence of the proposed mitigation and monitoring measures.
    Repeated exposures of individuals to relatively low levels of sound 
outside of preferred habitat areas are unlikely to significantly 
disrupt critical behaviors. Thus, even repeated Level B harassment of 
some small subset of an overall stock is unlikely to result in any 
significant realized decrease in viability for the affected 
individuals, and thus would not result in any adverse impact to the 
stock as a whole. Instances of more severe behavioral harassment are 
expected to be minimized by proposed mitigation and monitoring 
measures. Effects on individuals that are taken by Level B harassment, 
on the basis of reports in the literature as well as monitoring from 
other similar activities, will likely be limited to reactions such as 
increased swimming speeds, increased surfacing time, or decreased 
foraging (if such activity were occurring) (e.g., Thorson and Reyff, 
2006; HDR, Inc., 2012; Lerma, 2014). Most likely, individuals will 
simply move away from the sound source and temporarily avoid the area 
where pile driving is occurring. Therefore, we expect that animals 
disturbed by project sound would simply avoid the area during pile 
driving in favor of other, similar habitats. We expect that any 
avoidance of the project area by marine mammals would be temporary in 
nature and that any marine mammals that avoid the project area during 
construction activities would not be permanently displaced.
    Feeding behavior is not likely to be significantly impacted, as 
prey species are mobile and are broadly distributed throughout the 
project area; therefore, marine mammals that may be temporarily 
displaced during construction activities are expected to be able to 
resume foraging once they have moved away from areas with disturbing 
levels of underwater noise. Because of the temporary nature of the 
disturbance and the availability of similar habitat and resources in 
the surrounding area, the impacts to marine mammals and the food 
sources that they utilize are not expected to cause significant or 
long-term consequences for individual marine mammals or their 
populations. There are no areas of notable biological significance for 
marine mammal feeding known to exist in the project area. In addition, 
there are no rookeries, mating areas, calving areas or migratory areas 
known to be biologically important to marine mammals within the 
proposed project area.
    NMFS concludes that exposures to marine mammals due to the proposed 
project would result in only short-term effects to individuals exposed. 
Marine mammals may temporarily avoid the immediate area but are not 
expected to permanently abandon the area. Impacts to breeding, feeding, 
sheltering, resting, or migration are not expected, nor are shifts in 
habitat use, distribution, or foraging success. NMFS does not 
anticipate the marine mammal takes that would result from the proposed 
project would impact annual rates of recruitment or survival.
    As described above, north Atlantic right, humpback, and minke 
whales, and gray, harbor and harp seals are experiencing ongoing UMEs. 
For North Atlantic right whales, as described above, no injury as a 
result of the proposed project is expected or proposed for 
authorization, and Level B harassment takes of right whales are 
expected to be in the form of avoidance of the immediate area of 
construction. In addition, the number of exposures above the Level B 
harassment threshold are minimal (i.e., 2). As no injury or mortality 
is expected or proposed for authorization, and Level B harassment of 
North Atlantic right whales will be reduced to the level of least 
practicable adverse impact through use of proposed mitigation measures, 
the proposed authorized takes of right whales would not exacerbate or 
compound the ongoing UME in any way. For minke whales, although the 
ongoing UME is under investigation (as occurs for all UMEs), this event 
does not provide cause for concern regarding population level impacts, 
as the likely population abundance is greater than 20,000

[[Page 45982]]

whales. Even though the PBR value is based on an abundance for U.S. 
waters that is negatively biased and a small fraction of the true 
population abundance, annual M/SI does not exceed the calculated PBR 
value for minke whales. With regard to humpback whales, the UME does 
not yet provide cause for concern regarding population-level impacts. 
Despite the UME, the relevant population of humpback whales (the West 
Indies breeding population, or distinct population segment (DPS)) 
remains healthy. The West Indies DPS, which consists of the whales 
whose breeding range includes the Atlantic margin of the Antilles from 
Cuba to northern Venezuela, and whose feeding range primarily includes 
the Gulf of Maine, eastern Canada, and western Greenland, was delisted. 
The status review identified harmful algal blooms, vessel collisions, 
and fishing gear entanglements as relevant threats for this DPS, but 
noted that all other threats are considered likely to have no or minor 
impact on population size or the growth rate of this DPS (Bettridge et 
al., 2015). As described in Bettridge et al. (2015), the West Indies 
DPS has a substantial population size (i.e., approximately 10,000; 
Stevick et al., 2003; Smith et al., 1999; Bettridge et al., 2015), and 
appears to be experiencing consistent growth.
    With regard to gray seals, harbor seals and harp seals, although 
the ongoing UME is under investigation, the UME does not yet provide 
cause for concern regarding population-level impacts to any of these 
stocks. For harbor seals, the population abundance is over 75,000 and 
annual M/SI (345) is well below PBR (2,006) (Hayes et al., 2018). For 
gray seals, the population abundance is over 27,000, and abundance is 
likely increasing in the U.S. Atlantic EEZ and in Canada (Hayes et al., 
2018). For harp seals, the current population trend in U.S. waters is 
unknown, as is PBR (Hayes et al., 2018), however the population 
abundance is over 7 million seals, suggesting that the UME is unlikely 
to result in population-level impacts (Hayes et al., 2018).
    Proposed authorized takes by Level A harassment for all species are 
very low (i.e., no more than 12 takes by Level A harassment proposed 
for any of these species) and as described above, any Level A 
harassment would be expected to be in the form of slight PTS, i.e. 
minor degradation of hearing capabilities which is not likely to 
meaningfully affect the ability to forage or communicate with 
conspecifics. No serious injury or mortality is expected or proposed 
for authorization, and Level B harassment of North Atlantic right, 
humpback and minke whales and gray, harbor and harp seals will be 
reduced to the level of least practicable adverse impact through use of 
proposed mitigation measures. As such, the proposed authorized takes of 
North Atlantic right, humpback and minke whales and gray, harbor and 
harp seals would not exacerbate or compound the ongoing UMEs in any 
way.
    In summary and as described above, the following factors primarily 
support our preliminary determination that the impacts resulting from 
this activity are not expected to adversely affect the species or stock 
through effects on annual rates of recruitment or survival:
     No mortality or serious injury is anticipated or proposed 
for authorization;
     The anticipated impacts of the proposed activity on marine 
mammals would be temporary behavioral changes due to avoidance of the 
project area and limited instances of Level A harassment in the form of 
a slight PTS for two marine mammal stocks;
     Potential instances of exposure above the Level A 
harassment threshold are expected to be relatively low for most 
species; any potential for exposures above the Level A harassment 
threshold would be minimized by proposed mitigation measures including 
clearance zones;
     Total proposed authorized takes as a percentage of 
population are low for all species and stocks (i.e., less than 24 
percent for one stock and less than 7 percent for the remaining 10 
stocks);
     The availability of alternate areas of similar habitat 
value for marine mammals to temporarily vacate the project area during 
the proposed project to avoid exposure to sounds from the activity;
     Effects on species that serve as prey species for marine 
mammals from the proposed project are expected to be short-term and are 
not expected to result in significant or long-term consequences for 
individual marine mammals, or to contribute to adverse impacts on their 
populations;
     There are no known important feeding, breeding, calving or 
migratory areas in the project area.
     The proposed mitigation measures, including visual and 
acoustic monitoring, clearance zones, and soft start, are expected to 
minimize potential impacts to marine mammals.
    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 proposed monitoring and 
mitigation measures, NMFS preliminarily finds that the total marine 
mammal take from the proposed activity will have a negligible impact on 
all affected marine mammal species or stocks.

Small Numbers

    As noted above, only small numbers of incidental take may be 
authorized under sections 101(a)(5)(A) and (D) of the MMPA for 
specified activities other than military readiness activities. The MMPA 
does not define small numbers and so, in practice, where estimated 
numbers are available, NMFS compares the number of individuals taken to 
the most appropriate estimation of abundance of the relevant species or 
stock in our determination of whether an authorization is limited to 
small numbers of marine mammals. Additionally, other qualitative 
factors may be considered in the analysis, such as the temporal or 
spatial scale of the activities.
    We propose to authorize incidental take of 11 marine mammal stocks. 
The total amount of taking proposed for authorization is less than 24 
percent for one of these stocks, and less than 7 percent for all 
remaining stocks (Table 11), which we consider to be relatively small 
percentages and we preliminarily find are small numbers of marine 
mammals relative to the estimated overall population abundances for 
those stocks.
    Based on the analysis contained herein of the proposed activity 
(including the proposed mitigation and monitoring measures) and the 
anticipated take of marine mammals, NMFS preliminarily finds that small 
numbers of marine mammals will be taken relative to the population size 
of all affected species or stocks.

Unmitigable Adverse Impact Analysis and Determination

    There are no relevant subsistence uses of the affected marine 
mammal stocks or species implicated by this action. Therefore, NMFS has 
determined that the total taking of affected species or stocks would 
not have an unmitigable adverse impact on the availability of such 
species or stocks for taking for subsistence purposes.

Endangered Species Act (ESA)

    Section 7(a)(2) of the Endangered Species Act of 1973 (ESA: 16 
U.S.C. 1531 et seq.) requires that each Federal agency insure that any 
action it authorizes, funds, or carries out is not likely to jeopardize 
the continued existence of any endangered or threatened species or 
result in the destruction or adverse modification of designated 
critical habitat. To ensure

[[Page 45983]]

ESA compliance for the issuance of IHAs, NMFS consults internally 
whenever we propose to authorize take for endangered or threatened 
species.
    NMFS is proposing to authorize take of North Atlantic right whales 
and fin whales, which are listed under the ESA. The NMFS Office of 
Protected Resources has requested initiation of Section 7 consultation 
with the NMFS Greater Atlantic Regional Fisheries Office for the 
issuance of this IHA. NMFS will conclude the ESA consultation prior to 
reaching a determination regarding the proposed issuance of the 
authorization.

Proposed Authorization

    As a result of these preliminary determinations, NMFS proposes to 
issue an IHA to Transco for conducting construction activities in 
Raritan Bay for a period of one year, provided the previously mentioned 
mitigation, monitoring, and reporting requirements are incorporated. A 
draft of the proposed IHA can be found at: www.fisheries.noaa.gov/permit/incidental-take-authorizations-under-marine-mammal-protection-act.

Request for Public Comments

    We request comment on our analyses, the proposed authorization, and 
any other aspect of this Notice of Proposed IHA for the proposed 
action. We also request at this time comment on the potential renewal 
of this proposed IHA as described in the paragraph below. Please 
include with your comments any supporting data or literature citations 
to help inform decisions on the request for this IHA or a subsequent 
Renewal.
    On a case-by-case basis, NMFS may issue a one-year IHA renewal with 
an additional 15 days for public comments when (1) another year of 
identical or nearly identical activities as described in the Specified 
Activities section of this notice is planned or (2) the activities as 
described in the Specified Activities section of this notice would not 
be completed by the time the IHA expires and a Renewal would allow for 
completion of the activities beyond that described in the Dates and 
Duration section of this notice, provided all of the following 
conditions are met:
     A request for renewal is received no later than 60 days 
prior to expiration of the current IHA.
     The request for renewal must include the following:
    (1) An explanation that the activities to be conducted under the 
requested Renewal are identical to the activities analyzed under the 
initial IHA, are a subset of the activities, or include changes so 
minor (e.g., reduction in pile size) that the changes do not affect the 
previous analyses, mitigation and monitoring requirements, or take 
estimates (with the exception of reducing the type or amount of take 
because only a subset of the initially analyzed activities remain to be 
completed under the Renewal).
    (2) A preliminary monitoring report showing the results of the 
required monitoring to date and an explanation showing that the 
monitoring results do not indicate impacts of a scale or nature not 
previously analyzed or authorized.
     Upon review of the request for Renewal, the status of the 
affected species or stocks, and any other pertinent information, NMFS 
determines that there are no more than minor changes in the activities, 
the mitigation and monitoring measures will remain the same and 
appropriate, and the findings in the initial IHA remain valid.

    Dated: August 28, 2019.
Donna S. Wieting,
Director, Office of Protected Resources, National Marine Fisheries 
Service.
[FR Doc. 2019-18931 Filed 8-30-19; 8:45 am]
 BILLING CODE 3510-22-P