[Federal Register Volume 85, Number 52 (Tuesday, March 17, 2020)]
[Notices]
[Pages 15125-15142]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2020-05385]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

[RTID 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; issuance of an incidental harassment authorization.

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[[Page 15126]]

SUMMARY: In accordance with the regulations implementing the Marine 
Mammal Protection Act (MMPA) as amended, notification is hereby given 
that NMFS has issued an incidental harassment authorization (IHA) to 
Transcontinental Gas Pipe Line Company, LLC (Transco), a subsidiary of 
Williams Partners L.P., to incidentally harass, by Level A and Level B 
harassment, marine mammals incidental to construction activities 
associated with the Raritan Bay Pipeline.

DATES: This authorization is valid from May 1, 2021 through April 30, 
2022.

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 
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.

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 the 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. 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. 
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).
    A detailed description of Transco's planned activities is provided 
in the notice of proposed IHA (84 FR 45955; September 9, 2019). Since 
that time, no changes have been made to the activities. Therefore, a 
detailed description is not provided here. Please refer to that notice 
for the detailed description of the specified activity. Mitigation, 
monitoring, and reporting measures are described in detail later in 
this document (please see ``Mitigation'' and ``Monitoring and 
Reporting'').

Comments and Responses

    A notice of proposed IHA was published in the Federal Register on 
September 9, 2019 (84 FR 45955). During the 30-day public comment 
period, NMFS received a comment letter from the Marine Mammal 
Commission (Commission) and one comment from a member of the general 
public. NMFS has posted the comments online at: www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-other-energy-activities-renewable.
    A summary of the public comments received and NMFS' responses to 
those comments are below.
    Comment 1: A member of the general public asked several questions 
including whether Transco demonstrated prior cooperation with NOAA for 
any previously-issued authorizations; whether Transco qualifies and 
trains the PSOs that will be responsible for marine mammal; what kind 
of reporting NOAA will receive regarding Transco's activities; how the 
environmental review for the proposed project is being handled to 
ensure that pipeline leakages and vibrational noise from operations are 
addressed; and the definition of ``take''.
    NMFS response: The answers to the commenter's questions are 
provided in the IHA application the notice of proposed IHA (84 FR 
45955; September 9, 2019). The commenter does not provide any 
substantive recommendations regarding the IHA therefore we have not 
made any revisions to the IHA in response to the comment.
    Comment 2: The Commission recommended that NMFS revise the numbers 
of authorized takes for gray and harbor seals by: Estimating a daily 
sightings rate (versus a monthly sightings rate); relying on 
observational data from Sandy Hook Bay as opposed to Cupsogue Beach 
Park; and, using the total estimated take of harbor seals to inform the 
number of gray seal takes

[[Page 15127]]

(rather than being reduced by the number of gray seal takes). The 
Commission recommended that NMFS authorize 833 Level B harassment takes 
and at least 14 Level A harassment takes of gray seals and that we 
authorize at least 1,593 Level A harassment takes and 6,136 Level B 
harassment takes of harbor seals.
    NMFS response: We agree with the Commission's recommendations to 
revise harbor and gray seal takes by estimating a daily sightings rate 
as opposed to a monthly sightings rate, and to use the total estimated 
takes of harbor seals to inform the number of gray seal takes, rather 
than reducing the number of harbor seal takes by the estimated number 
of gray seal takes; we have taken both of these steps in estimating 
revised take numbers in the final IHA. We do not agree with the 
Commission's recommendation to rely on observational data from Sandy 
Hook Bay as opposed to Cupsogue Beach Park for harbor seal take 
estimates because, while Sandy Hook Bay is closer to the project 
location, we do not consider the data from Sandy Hook Bay to be 
reliable for estimating a take estimate. The data from Sandy Hook Bay 
is based on a much smaller sample size (only 24 data points over a 
period of 10 years for Sandy Hook Bay compared with 32 surveys from 
2018-2019 for Cupsogue Beach Park) and is based on citizen science 
alone, as opposed to the data available from Cupsogue Beach Park which 
is based on systematic data collected over multiple years by the 
Coastal Research and Education Society of Long Island, which conducts 
research on marine mammals in the project area. We have authorized 
1,535 Level B harassment takes and 399 Level A harassment takes of gray 
seals, and 4,264 Level B harassment takes and 1,107 Level A harassment 
takes of harbor seals. Please see the ``Estimated Take'' section below 
for further details on the methods for determining the take estimates 
for harbor and gray seals.
    Comment 3: The Commission recommended that NMFS revise the numbers 
of authorized takes of humpback whales, specifically by obtaining the 
most recent 2018 and 2019 sightings data from Gotham Whale and using a 
daily sightings rate to estimate take, and including a sufficient 
number of Level A harassment takes of humpback whales based on 14 days 
of impact pile driving.
    NMFS response: We agree with the Commission's recommendations 
regarding the methods for estimating takes of humpback whales and have 
obtained the 2018 and 2019 sightings data from Gotham Whale, used a 
daily sightings rate to estimate take, and increased the number of 
authorized takes by Level A harassment based on 14 days of impact pile 
driving. We have authorized 35 Level B harassment takes and 14 Level A 
harassment takes of humpback whales. Please see the ``Estimated Take'' 
section below for further details on the methods for determining the 
take estimates for humpback whales.
    Comment 4: The Commission recommended that NMFS increase the number 
of Level B harassment takes of North Atlantic right whales from two to 
at least three based on average group size.
    NMFS response: The Commission refers to authorized take numbers of 
right whales in three previously issued IHAs as justification for 
increasing group size from two to at least three North Atlantic right 
whales in this IHA. One previously-issued IHA cited by the Commission 
(NMFS, 2015; 80 FR 27635) authorized three takes of right whales 
apparently to account for group size; however, a review of that IHA 
shows the citation relied upon for that group size estimate, which 
summarized right whale sightings during vessel-based surveys offshore 
New Jersey from 2008-2009, reported group size ranged from one to two 
whales (Whitt et al., 2013). Another previously-issued IHA cited by the 
Commission (NMFS, 2014; 79 FR 57538) authorized the take of five right 
whales; however, a review of that IHA shows that the authorized take 
number was based on the actual modeled number of takes, not on an 
estimate of mean group size. The third previously-issued IHA cited by 
the Commission (NMFS, 2014; 79 FR 52121) authorized the take of three 
right whales; however, a review of that IHA shows that the citation for 
mean group size, the Bureau of Land Management's Cetacean and Turtle 
Assessment Program (CeTAP), reported a mean group size of 2.6 right 
whales (CeTAP, 1982), but CeTAP surveys included areas of known feeding 
aggregations which would result in higher mean group size estimates. 
While larger group sizes of right whales are known to occur in areas of 
importance for feeding, the project area is not an important feeding 
area, therefore any right whales in the area would be expected to be 
migrating through the area. An average group size of two represents the 
best estimate for right whales that are migrating, and this is 
supported by sightings near the project area off New Jersey from 2008-
2009 (Whitt et al, 2013). We have therefore not revised the number of 
authorized Level B harassment takes of North Atlantic right whales.
    Comment 5: The Commission recommended that NMFS include a 
requirement for Skipjack to provide marine mammal observational 
datasheets or raw sightings data in its draft and final monitoring 
report.
    Response: NMFS agrees with the Commission's recommendation and has 
incorporated this requirement in the IHA.
    Comment 6: The Commission recommended that NMFS include a 
requirement to estimate the total takes by extrapolating Level A and B 
harassment takes to the proportion of the zones that are not visible by 
PSOs and ensure that Transco keeps a running tally of the total takes 
for each species while the project is underway.
    Response: NMFS agrees with the Commission's recommendation and has 
incorporated this requirement in the IHA.
    Comment 7: The Commission recommended that NMFS include the number 
and location of PSOs in the final IHA rather than referencing the 
application.
    Response: NMFS agrees with the Commission's recommendation and has 
incorporated this requirement in the IHA.

Changes From the Proposed IHA to Final IHA

    As described above, revisions have been made to the take estimates 
for harbor seals, gray seals and humpback whales. These changes are 
also described in greater detail in the ``Estimated Take'' section 
below.

Description of Marine Mammals in the Area of Specified Activity

    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).
    We expect that the species listed in Table 1 will potentially occur 
in the project area and will potentially be taken as a result of the 
proposed project. Table 1 summarizes information related to the 
population or stock, including regulatory status under the MMPA and ESA 
and potential biological removal

[[Page 15128]]

(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 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 1 are the most 
recent available at the time of publication and are available in the 
2018 Atlantic SARs (Hayes et al., 2019) available online at: 
www.fisheries.noaa.gov/action/2018-draft-marine-mammal-stock-assessment-reports-available.

                        Table 1--Marine Mammals Known To Occur in the Project Area That May Be Affected by the Specified Activity
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                                                                      Stock abundance
                                                      MMPA and ESA    (CV, Nmin, most        Predicted                                   Occurrence and
 Common name (scientific name)          Stock           status;      recent  abundance   abundance (CV) 3     PBR 4    Annual  M/SI 4    seasonality in
                                                     strategic (Y/       survey) 2                                                        project area
                                                          N) 1
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                                                               Toothed whales (Odontoceti)
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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;        ..................         48  unknown.......  Common year
                                  Coastal Migratory.                 4,759; 2015).                                                      round.
Common dolphin 6 (Delphinus      W. North Atlantic.  -;N            173,486 (0.55;           86,098 (0.12)        557  406...........  Common year
 delphis).                                                           55,690; 2011).                                                     round.
Harbor porpoise (Phocoena        Gulf of Maine/Bay   -;N            79,833 (0.32;          * 45,089 (0.12)        706  255...........  Common year
 phocoena).                       of Fundy.                          61,415; 2011).                                                     round.
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                Baleen whales (Mysticeti)
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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
 novaeangliae).                                                      a).                                                                round.
Minke whale 6 (Balaenoptera      Canadian East       -;N            20,741 (0.3;            * 2,112 (0.05)         14  7.5...........  Year round in
 acutorostrata).                  Coast.                             1,425; n/a).                                                       continental
                                                                                                                                        shelf and slope
                                                                                                                                        waters, occur
                                                                                                                                        seasonally.
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                                                                Earless seals (Phocidae)
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Gray seal 8 (Halichoerus         W. North Atlantic.  -;N            27,131 (0.10;       ..................      1,389  5,688.........  Common year
 grypus).                                                            25,908; n/a).                                                      round.
Harbor seal (Phoca vitulina)...  W. North Atlantic.  -;N            75,834 (0.15;       ..................      2,006  345...........  Common year
                                                                     66,884; 2012).                                                     round.
Harp seal (Pagophilus            W. North Atlantic.  -;N            7,411,000 (unk.;    ..................        unk  225,687.......  Rare
 groenlandicus).                                                     unk; 2014).
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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.


[[Page 15129]]

    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.
    A detailed description of the of the species likely to be affected 
by Transco's activities, including brief introductions to the species 
and relevant stocks as well as available information regarding 
population trends and threats, and information regarding local 
occurrence, were provided in the notice of proposed IHA (84 FR 45955; 
September 9, 2019); since that time, we are not aware of any changes in 
the status of these species and stocks; therefore, detailed 
descriptions are not provided here. Please refer to that notice for 
these descriptions. Please also refer to NMFS' website 
(www.fisheries.noaa.gov/find-species) for generalized species accounts.

Potential Effects of Specified Activities on Marine Mammals and Their 
Habitat

    The effects of underwater noise from Transco's construction 
activities have the potential to result in behavioral harassment of 
marine mammals in the vicinity of the survey area. The notice of 
proposed IHA (84 FR 45955; September 9, 2019) included a discussion of 
the effects of anthropogenic noise on marine mammals and the potential 
effects of underwater noise from Skipjack's survey activities on marine 
mammals and their habitat. That information and analysis is 
incorporated by reference into this final IHA determination and is not 
repeated here; please refer to the notice of proposed IHA (84 FR 45955; 
September 9, 2019).

Estimated Take

    This section provides an estimate of the number of incidental takes 
authorized 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 
mitigation and monitoring measures are expected to minimize the 
severity of such taking to the extent practicable. The 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 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 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 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 2 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 2--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.

[[Page 15130]]

 
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 [mu]Pa, and cumulative sound exposure level (LE) has
  a reference value of 1[mu]Pa2s. 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 3). 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 3 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.

                          Table 3--Modeled Pile Installation and Removal Source Levels
----------------------------------------------------------------------------------------------------------------
                                                             RMS (dB)                           SEL
               Pile diameter (in)                ---------------------------------------------------------------
                                                      Impact         Vibratory        Impact         Vibratory
----------------------------------------------------------------------------------------------------------------
                                                  Installation
----------------------------------------------------------------------------------------------------------------
10..............................................  ..............             150  ..............             150
24..............................................  ..............             160  ..............             160

[[Page 15131]]

 
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 4) (See Figure 8 in the IHA application for the representative 
locations).

        Table 4--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 4). 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

[[Page 15132]]

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 (threshold of 202 dB re 
1 [micro]Pa). 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 5 and 6. 
The resulting isopleth distances to Level A harassment thresholds are 
shown in Tables 7 and 8.

  Table 5--Inputs to NMFS Optional User Spreadsheet (NMFS, 2018) to Calculate Isopleth Distances to Level A Harassment Thresholds for Vibratory Driving
                                                                       and Removal
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                           Pile driving
                                                                             duration      Pile removal      Weighting                      Distance of
        Pile size  (representative pile location)          Source level   (hours) within     duration         factor        Propagation    source level
                                                             (RMS SPL)        24-hour     (hours) within    adjustment        (xLogR)       measurement
                                                                              period      24-hour 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 6-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 3) 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 4). 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

[[Page 15133]]

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 7 and 8.

 Table 7--Modeled Isopleth Distances to Level A and Level B Harassment Thresholds for Impact and Vibratory Pile
                                                  Installation
----------------------------------------------------------------------------------------------------------------
                                                     Low-         Mid-        High-                   Cetaceans
                                                  frequency    frequency    frequency      Phocid        and
                                                  cetaceans    cetaceans    cetaceans      seals       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 8--Modeled Isopleth Distances to Level A and Level B Harassment Thresholds for Vibratory Pile Removal
----------------------------------------------------------------------------------------------------------------
                                                     Low-         Mid-        High-                   Cetaceans
                                                  frequency    frequency    frequency      Phocid        and
                                                  cetaceans    cetaceans    cetaceans      seals       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

[[Page 15134]]

 
                                                       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
--------------------------------------------------------------------------------------------------------------------------------------------------------

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 online 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 7 and 8). 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

[[Page 15135]]

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 4), 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:

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 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 9).
    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 
humpback whales are known to occur in the project area, indicating that 
potential takes may occur and therefore should be accounted for. As the 
exposure estimate method described above resulted in zero exposures, 
other methods for calculating take were applied.
    Humpback whale sightings data from Gotham Whale, a whale watching 
organization that collects data on marine mammals in and around New 
York harbor and Raritan Bay, represent the best available information 
on humpback whale abundance in the project area. Based on Gotham 
Whale's sightings data, an estimate of the number of humpback whales 
observed per day was estimated by dividing the number of humpback whale 
observations by the number of trips. As sightings data from 2011 
through 2019 demonstrated an increasing trend in the number of 
sightings from 2011 through 2019, we used the number of sightings from 
2019 (which represented the highest number of sightings per day of all 
years) to develop a conservative take estimate for humpback whales. The 
daily sightings rate in 2019 (0.54 whales per day) was multiplied by 
the number of days of construction activities (65.5) to come up with an 
estimate of total takes by Level B harassment (i.e., 0.54 * 65.5 = 35 
takes; Table 9). To calculate takes by Level A harassment, we 
conservatively estimated that one humpback whale may be taken by Level 
A harassment during each day of impact pile driving (14 days); thus, we 
have authorized 14 takes of humpback whales by Level A harassment.
    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 harbor seals were 
calculated using systematic data collected by CRESLI from November 18, 
2018 through April 28, 2019, where a total of 2,621 harbor seals were 
sighted at Cupsogue Beach Park. The total number of sightings was 
divided by the total number of survey days to come up with a daily 
sightings rate (82 seals per day). That number was then multiplied by 
the number of days of construction activities (65.5) to come up with an 
estimate of total takes by Level B harassment (i.e., 82 * 65.5 = 5,371 
takes). To calculate an estimate of takes by Level A harassment, the 
daily sightings rate was multiplied by the number of days of impact 
pile driving (14 days, for a total of 1,107 takes by Level A 
harassment).
    Data on gray seals in the project area was not available; however, 
anecdotal information indicates gray seals are present in the project 
area and may be taken by Transco's proposed activities. Therefore, to 
come up with an estimate of gray seal takes, a ratio of gray seals to 
harbor seals was estimated. While the data presented by Roberts et al. 
(2018) represent the best available density estimates for pinnipeds in 
the project area, that data does not differentiate by seal species. 
Thus the best available information on the ratio of gray seals to 
harbor seals comes from the U.S. Navy's OPAREA density estimates 
(Halpin et al. 2009; Navy 2007, 2012). The OPAREA data indicate the 
ratio of gray seals to harbor seals is 36 percent to 64 percent, 
respectively. Thus, the estimated number of takes by Level A harassment 
and Level B harassment for harbor seals (1,107 and 5,371 respectively) 
were multiplied by 0.36 to come up with an estimate of total takes by 
Level A harassment and Level B

[[Page 15136]]

harassment for gray seals (399 and 1,934 respectively).
    Note that the take estimate methods described above for harbor 
seals, gray seals, and humpback whales have been revised from the 
methods proposed in the notice of proposed IHA (84 FR 45955; September 
9, 2019) based on public comments received in response to the notice of 
proposed IHA, and authorized take numbers have also been revised from 
the numbers proposed in the notice of proposed IHA as result of these 
changes.
    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. Authorized take numbers are shown 
in Table 9.

   Table 9--Total Numbers of Potential Incidental Takes of Marine Mammals Authorized and Authorized Takes as a
                                            Percentage of Population
----------------------------------------------------------------------------------------------------------------
                                                                                                       Total
                                                                                                    authorized
                                                    Authorized      Authorized         Total           takes
                     Species                      takes by Level  takes by Level    authorized    authorized  as
                                                   A harassment    B harassment        takes       a  percentage
                                                                                                  of stock taken
                                                                                                         *
----------------------------------------------------------------------------------------------------------------
Fin whale.......................................               0               5               5             0.1
Humpback Whale..................................              14              35              49             3.0
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.......................................             399           1,934           2,333             8.6
Harbor seal.....................................           1,107           5,371           6,478             8.5
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
  1. 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 authorized 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.
     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
     Level A harassment take numbers do not account for the 
effectiveness of mitigation and monitoring measures in reducing the 
number of takes.

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

[[Page 15137]]

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

  Table 10--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 11). The 500 m zone is 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. During in-
water construction activities that do not entail pile driving (e.g., 
excavating, dredging, and use of other heavy machinery), if a marine 
mammal comes within 10-m of the construction equipment, Transco must 
cease operations and reduce vessel speed to the minimum level required 
to maintain steerage and safe working conditions.

    Table 11--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
------------------------------------------------------------------------


[[Page 15138]]

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 must be conducted by qualified, trained PSOs. One 
PSO must be stationed on an escort boat and the other either on the 
construction barge or another vessel during impact and vibratory pile 
installation and removal. The escort boat location may 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 (PSOs may 
conduct duties not related to marine mammal observation beyond four 
consecutive 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;
    (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 during all pile driving and removal activities (during 
non-pile driving construction activities (e.g., excavating, dredging, 
and use of other heavy machinery), construction personnel may act as 
observers for the 10-m exclusion zone described above. Construction 
personnel acting as observers for the 10-m exclusion zone must have no 
other construction-related responsibilities during times of marine 
mammal monitoring);
     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 (1,640 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.

[[Page 15139]]

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 determined 
that the 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.

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 
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 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;

[[Page 15140]]

     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 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 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 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 
authorized are very low for all marine mammal stocks and species: For 9 
of 11 stocks, we authorize no takes by Level A harassment; for the 
remaining two stocks we authorize no more than 12 takes by Level A 
harassment of a low level that would not be expected to impact 
reproduction or survival of any individuals. No serious injury or 
mortality of any marine mammal stocks are anticipated or authorized. 
Serious injury or mortality as a result of the proposed activities 
would not be expected even in the absence of the 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, in this case, 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 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

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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 authorized, 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 authorized, and 
Level B harassment of North Atlantic right whales will be reduced to 
the level of least practicable adverse impact through use of mitigation 
measures, the 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 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).
    Authorized takes by Level A harassment for all species are very low 
(i.e., no more than 12 takes by Level A harassment authorized 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 authorized, 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 mitigation measures. As such, the 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 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 
authorized;
     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 zero for most species and 
relatively low for others; any PTS incurred is expected to be of a low 
level;
     Total 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 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

[[Page 15142]]

specified activity on marine mammals and their habitat, and taking into 
consideration the implementation of the monitoring and mitigation 
measures, NMFS 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 are authorizing the incidental take of 11 marine mammal stocks. 
The total amount of taking authorized is less than 24 percent for one 
of these stocks, and less than 9 percent for all remaining stocks 
(Table 9), which we consider to be relatively small percentages and we 
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 mitigation and monitoring measures) and the anticipated 
take of marine mammals, NMFS 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.

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 determined 
that the proposed action qualifies to be categorically excluded from 
further NEPA review.

Endangered Species Act (ESA)

    Section 7(a)(2) of the Endangered Species Act of 1973 (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 ESA compliance for the issuance of IHAs, NMFS 
consults internally, in this case with the NMFS Greater Atlantic 
Regional Fisheries Office (GARFO), whenever we propose to authorize 
take for endangered or threatened species.
    The NMFS Office of Protected Resources Permits and Conservation 
Division is authorizing the incidental take of two species of marine 
mammals which are listed under the ESA: The North Atlantic right whale 
and fin whale. We requested initiation of consultation under Section 7 
of the ESA with NMFS GARFO on August 14, 2019, for the issuance of this 
IHA. On February 25, 2020, NMFS GARFO determined our issuance of the 
IHA to Transco was not likely to adversely affect any ESA-listed 
species or result in the take of any marine mammals in violation of the 
ESA.

Authorization

    NMFS has issued 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.

    Dated: March 11, 2020.
Donna Wieting,
Director, Office of Protected Resources, National Marine Fisheries 
Service.
[FR Doc. 2020-05385 Filed 3-16-20; 8:45 am]
 BILLING CODE 3510-22-P