[Federal Register Volume 85, Number 174 (Tuesday, September 8, 2020)]
[Notices]
[Pages 55415-55434]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2020-19688]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

[RTID 0648-XA395]


Takes of Marine Mammals Incidental To Specified Activities; 
Taking Marine Mammals Incidental to Marine Site Characterization 
Surveys Off of Coastal Virginia

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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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 
Dominion Energy Virginia (Dominion) to incidentally harass, by Level B 
harassment only, marine mammals during marine site characterization 
surveys in the areas of the Commercial Lease of Submerged Lands for 
Renewable Energy Development on the Outer Continental Shelf (OCS) 
Offshore Virginia (Lease No. OCS-A-0483) as well as in coastal waters 
where an export cable corridor will be established in support of the 
Coastal Virginia Offshore Wind Commercial (CVOW Commercial) Project.

DATES: This Authorization is effective from August 28, 2020 to August 
27, 2021.

FOR FURTHER INFORMATION CONTACT: Rob Pauline, 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: https://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 of 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 the 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 the 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, 2020, NMFS received a request from Dominion for an 
IHA to take marine mammals incidental to marine site characterization 
surveys in the areas of the Commercial Lease of Submerged Lands for 
Renewable Energy Development on the OCS Offshore Virginia (Lease No. 
OCS-A-0483) as well as in coastal waters where an export cable corridor 
will be established in support of the offshore wind project. Dominion's 
planned marine site characterization surveys include HRG and 
geotechnical survey activities. For the purpose of this IHA the Lease 
Area and export cable corridors are collectively referred to as the 
Survey Area. Geophysical and shallow geotechnical survey activities are 
anticipated to be supported by up to four vessels. The vessels will 
transit a combined estimated total of 121.54 km of survey lines per 
day. The application was deemed adequate and complete on May 12, 2020. 
Dominion's request is for take of a small number of 9 species by Level 
B harassment only. Neither Dominion nor NMFS expects serious injury or 
mortality to result from this activity and, therefore, an IHA is 
appropriate.

Description of Specified Activity

Overview

    Dominion plans to conduct high-resolution geophysical (HRG) and 
geotechnical surveys in support of offshore wind development projects 
in the areas of Commercial Lease of Submerged Lands for Renewable 
Energy Development on the OCS offshore Virginia (#OCS-A 0483) and along 
potential submarine cable routes to landfall locations in Virginia.
    The purpose of the marine site characterization surveys is to 
support the site characterization, facilities siting, and engineering 
design of offshore Project facilities including wind turbine 
generators, offshore substation(s), and submarine cables within the 
Lease Area and export cable corridor. The estimated duration of HRG 
survey activities is estimated to last approximately 161 days and will 
commence as soon as possible. Of those days, surveys will be conducted 
for 149 days in the Lease Area and 12 days in the export cable 
corridor. This schedule is based on 24-hour operations and includes 
potential down time due to inclement weather. There will be up to four 
survey vessels operating concurrently and the total distance covered by 
both actively operating HRG equipment is approximately 121.5 km (75.5 
mi) per day.
    The HRG survey activities planned by Dominion are described in 
detail in the notice of proposed IHA (85 FR 36537; June 17, 2020). The 
HRG equipment planned for use is shown in Table 1.

[[Page 55416]]



                                      Table 1--Summary of Geophysical Survey Equipment Planned for Use by Dominion
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                                                                                                                                               Pulse
             HRG system                 Representative HRG    Operating  frequencies   RMS source  Peak source     Primary beam  width        duration
                                             equipment                 (kHz)           level \1\     level \1\          (degrees)          (millisecond)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Subsea Positioning/USBL.............  Sonardyne Ranger 2      35-55.................          194          191  90.......................             1
                                       USBL.
                                      EvoLogics S2CR........  48-78.................          178          186  Omnidirectional..........       500-600
                                      ixBlue Gaps...........  20-30.................          191          194  200......................          9-11
Multibeam Echosounder...............  R2Sonics 2026.........  170-450...............          191          221  0.45 x 0.45-1 x 1........   0.015-1.115
Synthetic Aperture Sonar (SAS),       Kraken Aquapix........  337...................          210          213  >135 vertical, 1                   1-10
 combined bathymetry/Sidescan \2\.                                                                               horizontal.
Side Scan Sonar \2\.................  Edgetech 4200 dual      300 and 600...........      \3\ 206      \3\ 212  140......................          5-10
                                       frequency.
Parametric SBP......................  Innomar SES-2000        85-115................      \4\ 241          247  2........................        0.07-1
                                       medium 100.
Non-Parametric SBP..................  Edgetech 216 Chirp....  2-16..................          179          196  15-25....................          5-40
                                      Edgetech 512 Chirp....  0.5-12................          179      \5\ 191  16-41....................            20
Medium Penetration Seismic..........  GeoMarine Dual 400      0.25-4................          200      \6\ 210  Omnidirectional..........       0.5-0.8
                                       Sparker 800J.
                                      Applied Acoustics S-    0.5-3.5...............      \7\ 203      \7\ 213  \8\ 60...................            10
                                       Boom (Triple Plate
                                       Boomer 1000J).
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\1\ Source levels reported by manufacturer unless otherwise noted.
\2\ Operating frequencies are above all relevant marine mammal hearing thresholds, so are not assessed in this IHA.
\3\ The source levels are based on data from Crocker and Fratantonio (2016) for the EdgeTech 4200 for 100 percent power and 100 kHz.
\4\ The equipment specification sheets indicates a peak source level of 247 dB re 1 [mu]PA m. The average difference between the peak and SPLRMS source
  levels for sub-bottom profilers measured by Crocker and Fratantonio (2016) was 6 dB. Therefore, the estimated SPLRMS sound level is 241 dB re 1 [mu]PA
  m.
\5\ The source level are based on data from Crocker and Fratantonio (2016) for the EdgeTech 512i for 100 percent power.
\6\ The source levels were provided by the manufacturer within the document titled ``Noise Level Stacked 400--tuned''.
\7\ The source levels are based on data from Crocker and Fratantonio (2016) for the Applied Acoustics S-Boom with CSP-N Energy Source set at 1000
  Joules.
\8\ The beam width was based on data from Crocker and Fratantonio (2016) for the Applied Acoustics S-Boom. dB re 1 [mu]Pa m--decibels referenced to 1
  microPascal at 1 meter.

    As described above, detailed description of Vineyard Wind's planned 
surveys is provided in the notice of proposed IHA (85 FR 36537; June 
17, 2020). 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 below).

Comments and Responses

    A notice of proposed IHA was published in the Federal Register on 
June 17, 2020 (85 FR 365372). During the 30-day public comment period, 
NMFS received comment letters from the Marine Mammal Commission 
(Commission) and the Southern Environmental Law Center (SELC) who 
submitted comments on behalf of Natural Resources Defense Council, 
National Wildlife Federation, Conservation Law Foundation, Defenders of 
Wildlife, Whale and Dolphin Conservation, Surfrider Foundation, the 
Nature Conservancy, Sierra Club Virginia Chapter, Assateague Coastal 
Trust, Mass Audubon, NY4WHALES, the International Marine Mammal Project 
of Earth Island Institute, and Inland Ocean Coalition. 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 from the 
Commission and SELC as well as NMFS' responses to those comments are 
below.
    Comment 1: The Commission recommended that NMFS (1) specify the 
references for all source levels and use consistent source levels for 
the same equipment that operates under the same parameters amongst the 
various action proponents, (2) use appropriate pulse durations and 
repetition rates, (3) pair source levels with the appropriate operating 
frequencies, and (4) consistently discount sources both within the same 
Federal Register notice and among the notices
    Response: NMFS concurs with the Commission's recommendations and 
will work to ensure that the measures listed above are followed.
    Comment 2: The Commission indicated that NMFS recently used a 
source level of 179 decibels (dB) re 1micropascals root-mean-square 
([mu]Pa rms) at 1 meter (m) from Crocker and Fratantonio (2016) for the 
EdgeTech 216 Chirp. In this instance, NMFS used a source level of 193 
dB re 1 [mu]Pa rms at 1 m for the EdgeTech 216 Chirp based on 
manufacturer's specifications.
    Response: NMFS recommends using data from Crocker and Fratantonio 
(2016). The source level for the EdgeTech 216 Chirp has been changed in 
the final notice of issuance to 179 dB to match Crocker and Fratantonio 
(2016).
    Comment 3: The Commission noted that Crocker and Fratantonio (2016) 
determined that the source level for the EdgeTech 512i Chirp operating 
at 100-percent power at 0.7-12 kiloHertz (kHz) with a 20-millisecond 
(msec) pulse duration was 179 dB re 1 [mu]Pa rms at 1 m, not 177 dB re 
1 [mu]Pa rms at 1 m as indicated by NMFS.
    Response: The source level has been changed to 179 dB in the final 
notice of issuance to match Crocker and Fratantonio (2016).
    Comment 4: The Commission noted that the source level for the 
Sonardyne Ranger 2 (Sonardyne) USBL was 194 dB re 1 [mu]Pa rms at 1 m 
based on manufacturer's specifications, while 188 dB re 1 [mu]Pa rms at 
1 m was used for the proposed authorization, which also was apparently 
based on manufacturer's specifications.
    Response: The source level of 194 dB re 1 [mu]Pa rms is correct and 
is based on manufacturer's specifications.
    Comment 5: The Commission noted that NMFS incorrectly paired the 
241 dB re 1 [mu]Pa rms at 1 m source level at the primary frequencies 
of 85-115 kHz with the secondary low frequencies of 2-22 kHz for the 
Innomar SES-2000 medium 100 parametric (Innomar) SBP.
    Response: NMFS acknowledges this error and has made a correction in 
this Federal Register notice. Due to the narrow beamwidth of the 
Innomar, (2[deg]) any potential impacts to marine mammals the device of 
the device it can be discounted.
    Comment 6: The Commission asserted that for the Innomar SBP NMFS 
assumed that the Innomar SBP operates at a repetition rate of 0.5 Hz, 
or every 2 sec, rather than at 40 Hz and every 0.025 sec, which is 
consistent with all previous incidental harassment authorizations 
involving the Innomar SBP (e.g., Table 2 in 85 FR 31858). The pulse 
duration for the Innomar SBP also

[[Page 55417]]

ranges from 0.7 to 2 msec rather than 0.7 to 1 msec as described by 
Dominion.
    Response: The pulse duration discrepancy comes from the two 
possible operation modes for the Innomar. However, the repetition rate 
and pulse duration used were based on the expected settings from the 
manufacturer. No revision is required.
    Comment 7: The Commission noted that NMFS included various subsea 
positioning systems (Sonardyne USBL, Evologics 82CR (Evologics), and 
ixBlue Gaps) in Tables 1 and 5 of the Federal Register notice for the 
proposed IHA, but did not provide the relevant Level A and B harassment 
zones in Table 6 and 7, respectively.
    Response: NMFS has included this information in Table 5 and Table 6 
of this Federal Register final notice of issuance, which correspond to 
Table 6 and Table 7 of the proposed IHA.
    Comment 8: The Commission indicated that NMFS inconsistently 
described the frequency range of the EdgeTech 4200 dual frequency 
(EdgeTech) side-scan sonar
    Response: The EdgeTech 4200 side-scan sonar system can operate 
between 100 kHz and 900 kHz. NMFS inadvertently indicated that the 
operating frequency was 100 kHz. However, for the purposes of the 
Dominion survey, the device will operate at 300 kHz and 600 kHz. This 
information has been updated in the final notice of issuance.
    Comment 9: The Commission noted that neither Dominion nor NMFS used 
NMFS's user spreadsheet for Level B harassment in the proposed IHA, 
which resulted in overestimated Level B harassment zones for the subsea 
positioning systems and the EdgeTech 216. The Commission states that 
NMFS should be using the spreadsheet to estimate the Level B harassment 
zones.
    Response: Revisions have been made using the spreadsheet to items 
described and are included in Table 6 in this Federal Register notice 
of issuance. Note that the revisions differed by less than 1 m for the 
subsea positioning systems and less than 2 m for the Edgetech 216 when 
compared to the values in the proposed IHA.
    Comment 10: The Commission recommended that NMFS use its revised 
user spreadsheet, in-beam source levels, the actual beamwidth, and the 
maximum water depth in the Survey Area to estimate the Level B 
harassment zones for all future proposed authorizations involving HRG 
sources.
    Response: NMFS' interim guidance for determining Level B harassment 
zones from HRG sources includes all of the parameters listed above. We 
strongly recommend that applicants employ these tools, as we believe 
they are generally the best methodologies that are currently available.
    Comment 11: The Commission recommended that NMFS consult with its 
acoustic experts to determine how to estimate Level A harassment zones 
accurately, what Level A harassment zones are actually expected, and 
whether it is necessary to estimate Level A harassment zones for HRG 
surveys in general.
    Response: NMFS agrees with the Commission's recommendation and is 
working with our acoustic experts to evaluate the appropriate methods 
for determining the potential for Level A harassment from HRG surveys.
    Comment 12: To ensure that in-situ data are collected and analyzed 
appropriately, the Commission recommended that NMFS and the Bureau of 
Ocean Energy Management (BOEM) expedite efforts to develop and finalize 
methodological and signal processing standards for HRG sources.
    Response: NMFS agrees with the Commission that methodological and 
signal processing standards for HRG sources is warranted and is working 
on developing such standards. However, the effort is resource-dependent 
and NMFS cannot ensure such standards will be developed within the 
Commission's preferred time frame.
    Comment 13: The Commission recommended that NMFS follow a 
consistent approach and discount Level B harassment takes for those 
species in which the shutdown zones are equal to or greater than the 
Level B harassment zones for draft and final authorizations involving 
HRG surveys.
    Response: NMFS generally concurs with the Commission's position as 
it pertains to daylight operations. However, during night operations it 
is possible that some unseen number of marine mammals, other than large 
whales, could enter into the Level B harassment zone. Additionally, 
since shutdown is waived for certain dolphin genera, it is also 
possible these species could enter into the Level B harassment zone 
during both day and night operations.
    Comment 14: If BOEM's lease conditions remain in effect or modified 
conditions are implemented such that the shutdown zones are equal to or 
greater than the Level B harassment zones, the Commission recommended 
that NMFS implement the same approach that it proposed for mysticetes 
and sperm whales by discounting the Level B harassment takes for the 
relevant species and, if this approach applies to all species for which 
NMFS planned to issue an incidental taking authorization, inform 
Dominion that an incidental taking authorization is not required.
    Response: As noted above in the response to Comment #13, depending 
on the circumstances, take of marine mammals may be possible in some 
circumstances.
    Comment 15: The Commission recommended that NMFS evaluate the 
impacts of sound sources consistently across all applications and 
provide notice in its guidance to applicants and to the public 
regarding those sources that it has determined to be de minimis. The 
Commission also recommended that NMFS consider whether, in situations 
involving HRG surveys, IHAs are necessary given the small size of the 
Level B harassment zones, the various proposed shutdown requirements, 
and BOEM's lease-stipulated requirements. The Commission felt that NMFS 
should evaluate whether taking needs to be authorized for those sources 
that are not considered de minimis, including sparkers, and for which 
implementation of the various mitigation measures should be sufficient 
to avoid Level B harassment takes.
    Response: NMFS concurs with the Commission's recommendations and is 
currently working together with BOEM to develop a tool to assist 
applicants and NMFS in more quickly and efficiently identifying 
activities and mitigation approaches that are unlikely to result in 
take of marine mammals.
    Comment 16: The Commission recommended that NMFS require Dominion 
to report as soon as possible and cease project activities immediately 
in the event of an unauthorized injury or mortality of a marine mammal, 
including from a vessel strike, until NMFS's Office of Protected 
Resources (OPR) and the New England/Mid-Atlantic Regional Stranding 
Coordinator determine whether additional measures are necessary to 
minimize the potential for additional unauthorized takes.
    Response: NMFS has imposed a suite of measures in this IHA to 
reduce the risk of vessel strikes and does not anticipate, and has not 
authorized, any takes associated with vessel strikes. Further, in the 
event of a ship strike Dominion is required both to collect and report 
an extensive suite of information that NMFS has identified in order to 
evaluate the ship strike, and to notify OPR and the New England/Mid-
Atlantic Regional Stranding Coordinator as soon as feasible. At that 
point, as the Commission suggests, NMFS would work with the applicant 
to determine whether there are additional mitigation measures or 
modifications that could

[[Page 55418]]

further reduce the likelihood of vessel strike for the activities. 
However, given the existing requirements and the very low likelihood of 
a vessel strike occurring, the protective value of ceasing operations 
while NMFS and Dominion discuss potential additional mitigations in 
order to avoid a second highly unlikely event during that limited 
period is unclear, while a requirement for project activities to cease 
would not be practicable for a vessel that is operating on the open 
water. Therefore, NMFS does not concur that the measure is warranted 
and we have not included this requirement in the authorization. NMFS 
retains authority to modify the IHA and cease all activities 
immediately based on a vessel strike and will exercise that authority 
if warranted.
    Comment 17: The Commission and SELC consider the renewal process to 
be inconsistent the statutory requirements under section 101(a)(5)(D) 
of the MMPA and recommended that NMFS refrain from issuing renewals for 
any authorization and instead use its abbreviated Federal Register 
notice process.
    Response: In prior responses to comments about IHA Renewals (e.g., 
84 FR 52464; October 2, 2019), NMFS has explained how the Renewal 
process, as implemented, is consistent with the statutory requirements 
contained in section 101(a)(5)(D) of the MMPA and, therefore, we plan 
to continue to issue qualifying Renewals when the requirements outlined 
on our website are met. Thus, NMFS agrees with the Commission's 
recommendation that we should not issue a Renewal for any authorization 
unless it is consistent with the procedural requirements specified in 
section 101(a)(5)(D)(iii) of the MMPA.
    Additionally, regarding the recommendation to use abbreviated 
notices, we agree that they are a useful tool by which to increase 
efficiency in conjunction with the use of Renewals, but we disagree 
that their use alone would equally fulfill NMFS' goal to maximize 
efficiency and provide regulatory certainty for applicants, with no 
reduction in protections for marine mammals. The Renewal process, with 
its narrowly described qualifying actions, specific issuance criteria, 
and additional 15-day comment period, allows for NMFS to broadly commit 
to a 60-day processing time. This commitment, which would not be 
possible in the absence of this narrow definition and the 15-day 
additional comment period, provides both a meaningfully shortened 
processing time and regulatory certainty for planning purposes. 
Increasing the comment period for Renewals to 30 days would increase 
processing time by 25% and is unnecessary, given the legal sufficiency 
of the process as it stands, as described above, and no additional 
protections for marine mammals that would result. NMFS uses abbreviated 
notices when proposed actions do not qualify for Renewals, but still 
allow for reliance upon previous documentation and analyses. These 
abbreviated notice projects, which deviate from the narrow 
qualifications of a Renewal, require some additional time for the 
analyst to appropriately review the small changes from the initial IHA 
and further necessitate the 30-day public review required for a new 
IHA. NMFS has evaluated the use of both the Renewal and abbreviated 
notice processes, as well as the associated workload for each, and 
determined that using both of these processes provides maximum 
efficiency for the agency and applicants, regulatory certainty, and 
appropriate protections for marine mammals consistent with the 
statutory standards. Using the abbreviated notice process, however, is 
unnecessary and unwarranted for projects that meet the narrow 
qualifications for a Renewal IHA.
    As previously noted, we have found that the Renewal process is 
consistent with the statutory requirements of the MMPA and, further, 
promotes NMFS' goals of improving conservation of marine mammals and 
increasing efficiency in the MMPA compliance process. Therefore, we 
intend to continue implementing the Renewal process.
    Comment 18: SELC asserted that NMFS relied on incomplete estimates 
of marine mammal abundance, distribution, and density for the U.S. East 
Coast. SELC also recommended that NMFS analyze all data sources when 
calculating marine mammal densities and use the best available science.
    Response: NMFS has used the best available scientific information--
in this case the marine mammal density models developed by the Duke 
University Marine Geospatial Ecology Lab (MGEL) (Roberts et al., 2016, 
2017, 2018, 2020)--to inform our determinations. The commenters cite 
four alternate sources and recommend that NMFS incorporate information 
from these sources in modeling marine mammal exposure estimates, 
stating that the density maps produced by the Roberts et al. model do 
not fully reflect the abundance, distribution, and density of marine 
mammals for the U.S. East Coast. The first source cited by the 
commenters is a report by the Virginia Aquarium & Marine Science Center 
that summarizes aerial survey data in the Virginia Wind Energy Area 
from 2001-2017 (Mallette et al. 2018). However, a review of the most 
recent report on updates to the Duke MGEL density models (Roberts et 
al. 2020) shows that the aerial sightings data from the Virginia 
Aquarium & Marine Science Center report up through 2017 have been 
incorporated into the Duke MGEL density models used to model exposures 
in this IHA. In fact, the Mallette et al. (2018) and Roberts et al. 
(2020) reports share many of the same references. The second and third 
sources cited by the commenters summarize North Atlantic right whale 
passive acoustic monitoring (PAM) data in Virginia and elsewhere along 
the Atlantic coast (Salisbury et al., 2015; Davis et al. 2017). While 
NMFS agrees that these papers provide valuable information on right 
whale presence and habitat use in and near the project area, only the 
paper by Mallette et al. (2018) includes density information. As noted 
above, much of the source data for deriving densities was also 
incorporated into the most recent Roberts et al. (2020) model. However, 
the density for ESA-listed baleen whales (i.e., right and fin whales) 
during winter was 0.082 animals/100 km\2\ according to Mallette et al. 
(2018) while Roberts et al. (2020) determined the density for right 
whales only was between 0.25-0.50 animals/100 km\2\. The other papers 
do not provide density data that can readily be incorporated into 
exposure models and the commenters do not provide any recommendations 
as to how this PAM data would be incorporated into exposure estimates. 
The fourth source cited by the commenters is an article in the popular 
press about fishermen disentangling a North Atlantic right whale 50 
miles offshore Virginia in 2013; the commenters do not provide a 
recommendation as to how an anecdotal report of a single right whale 
off Virginia in 2013 would be incorporated into marine mammal exposure 
estimates.
    NMFS considered the most recent Roberts et al. (2020) data, which 
became available in August 2020, in the context of the specified 
activities, analysis, and take estimates included in the proposed IHA. 
While the latest density estimates are greater than the densities 
listed in the proposed IHA and the modeled right whale take by Level B 
harassment without mitigation would increase by a few animals, given 
the small area in which disturbance of right whales would be likely to 
occur and the much

[[Page 55419]]

larger required 500-m shutdown zone, this mitigation is still expected 
to effectively reduce take of animals to zero.
    We welcome future input from interested parties on data sources 
that may be of use in analyzing the potential presence and movement 
patterns of marine mammals in Mid-Atlantic waters. NMFS will review any 
recommended data sources and will continue to use the best available 
information. NMFS has used the best available scientific information--
in this case the marine mammal density models developed by the Duke 
Marine Geospatial Ecology Lab (MGEL) (Roberts et al. 2016, 2017, 2018, 
2020)--to inform our determinations.
    Comment 19: SELC advised NMFS to fund surveys and analyze collected 
data for the Mid-Atlantic region. They advised NMFS to develop a 
dataset that accurately reflects marine mammal presence and associated 
densities in the area.
    Response: NMFS agrees with SELC that continued surveys are 
warranted as is the analysis of collected data. We welcome the 
opportunity to participate in fora where implications of such data and 
development of a dataset would be discussed. Note, however, that NMFS 
will fund pertinent surveys based on agency priorities and budgetary 
considerations. Note that NOAA Fisheries just published Technical 
Memorandum NMFS-OPR-64: North Atlantic Right Whale Monitoring and 
Surveillance: Report and Recommendations of the National Marine 
Fisheries Service's Expert Working Group (https://www.fisheries.noaa.gov/resource/document/north-atlantic-right-whale-monitoring-and-surveillance-report-and-recommendations). This report 
includes recommendations for a comprehensive monitoring strategy to 
guide future analyses and data collection. NOAA Fisheries will consider 
the Expert Working Group's recommendations, as well as other relevant 
information, in its decision-making about right whale research and 
population monitoring.
    Comment 20: SELC recommended that NMFS take a precautionary 
approach with regard to siting and mitigation when permitting offshore 
wind activities in areas for which species distribution data are 
limited in Mid-Atlantic waters.
    Response: Neither the MMPA or NMFS's implementing regulations 
include references to, or requirements for, the precautionary approach, 
nor is there a clear, agreed-upon description of what the precautionary 
approach is or would entail in the context of the MMPA or any specific 
activity. Nevertheless, the MMPA by nature is inherently protective, 
including the requirement to mitigate to the least practicable adverse 
impacts (LPAI) on species or stocks and their habitat. This requires 
that NMFS assess measures in light of the LPAI standard. To ensure that 
we fulfill that requirement, NMFS considers all potential applicable 
measures (e.g., from recommendations or review of available data) that 
have the potential to reduce impacts on marine mammal species or 
stocks, their habitat, or subsistence uses of those stocks, regardless 
of whether those measures are characterized as ``precautionary.''
    NMFS is responsible for evaluating the impacts on marine mammals of 
the activities described by applicants in their request for an 
incidental harassment authorization in the context of the statutory 
requirements of section 101(a)(5)(D) of the MMPA.
    Comment 21: SELC asserted that the agency's assumptions regarding 
mitigation effectiveness are unfounded and cannot be used to justify 
any reduction in the number of takes authorized as was done for North 
Atlantic right whales. The reasons cited include: (i) The agency's 
reliance on a 160 dB threshold for behavioral harassment that is not 
supported by the best available scientific information, which indicates 
that Level B takes occur with near certainty at exposure levels well 
below the 160 dB; (ii) the agency relies on the assumption that marine 
mammals will take measures to avoid the sound even though studies have 
not found avoidance behavior to be generalizable among species and 
contexts and even though avoidance may itself constitute take under the 
MMPA; and (iii) the mitigation and monitoring protocols prescribed by 
the agency are inadequate at protecting marine mammals and do not 
comply with the MMPA.
    Response: The three comments provided by SELC are addressed 
individually below.
    (i) NMFS acknowledges that the 160-dB rms step-function approach is 
simplistic, and that an approach reflecting a more complex 
probabilistic function may more effectively represent the known 
variation in responses at different levels due to differences in the 
receivers, the context of the exposure, and other factors. The 
commenters suggested that our use of the 160-dB threshold implies that 
we do not recognize the science indicating that animals may react in 
ways constituting behavioral harassment when exposed to lower received 
levels (RL). However, we do recognize the potential for Level B 
harassment at exposures to RLs below 160 dB rms, in addition to the 
potential that animals exposed to RLs above 160 dB rms will not respond 
in ways constituting behavioral harassment (e.g., Malme et al., 1983, 
1984, 1985, 1988; McCauley et al., 1998, 2000a, 2000b; Barkaszi et al., 
2012; Stone, 2015a; Gailey et al., 2016; Barkaszi and Kelly, 2018). 
These comments appear to evidence a misconception regarding the concept 
of the 160-dB threshold. While it is correct that in practice it works 
as a step-function, i.e., animals exposed to RLs above the threshold 
are considered to be ``taken'' and those exposed to levels below the 
threshold are not, it is in fact intended as a sort of mid-point of 
likely behavioral responses (which are extremely complex depending on 
many factors including species, noise source, individual experience, 
and behavioral context). What this means is that, conceptually, the 
function recognizes that some animals exposed to levels below the 
threshold will in fact react in ways that are appropriately considered 
take, while others that are exposed to levels above the threshold will 
not. Use of the 160-dB threshold allows for a simplistic quantitative 
estimate of take, while we can qualitatively address the variation in 
responses across different RLs in our discussion and analysis.
    As behavioral responses to sound depend on the context in which an 
animal receives the sound, including the animal's behavioral mode when 
it hears sounds, prior experience, additional biological factors, and 
other contextual factors, defining sound levels that disrupt behavioral 
patterns is extremely difficult. Even experts have not previously been 
able to suggest specific new criteria due to these difficulties (e.g., 
Southall et al. 2007; Gomez et al., 2016).
    (ii) SELC disagreed with NMFS' assumption that marine mammals move 
away from sound sources. The SELC claimed that studies have not found 
avoidance behavior to be generalizable among species and contexts, and 
even though avoidance may itself constitute take under the MMPA. 
Importantly, the commenters mistakenly seem to believe that the NMFS' 
does not consider avoidance as a take, and that the concept of 
avoidance is used as a mechanism to reduce overall take--this is not 
the case. Avoidance of loud sounds is a well-documented behavioral 
response, and NMFS often accordingly accounts for this avoidance by 
reducing the number of injurious exposures, which would occur in very 
close proximity to the source and necessitate a longer duration of 
exposure. However,

[[Page 55420]]

when Level A harassment takes are reduced in this manner, they are 
changed to Level B harassment takes, in recognition of the fact that 
this avoidance or other behavioral responses occurring as a result of 
these exposures are still take. NMFS does not reduce the overall amount 
of take as a result of avoidance.
    (iii) SELC questioned the effectiveness of the mitigation and 
monitoring measures proposed to be authorized. They specifically 
recommended that seasonal restrictions should be established and 
consideration should be given to species for which an unusual mortality 
event (UME) has been declared. Note that NMFS is requiring Dominion to 
comply with restrictions associated with identified seasonal management 
areas (SMA) and they must comply with dynamic management area 
restrictions (DMAs), if any DMAs are established near the Project Area. 
Furthermore, we have established a 500-m shutdown zone for North 
Atlantic right whales which is five times as large as the greatest 
Level B harassment isopleth calculated for the specified activities for 
this IHA. The largest behavioral isopleth is 100 m associated with the 
Geo Marine Dual 400 Sparker 800J while isopleths for remaining HRG 
devices planned for use by Dominion are considerably less.
    Comment 22: SELC recommended that NMFS should acknowledge the 
potential for the use of HRG equipment to result in take by Level A 
harassment, especially for animals with high-frequency hearing ranges, 
including harbor porpoises. They noted that in previous authorizations 
for HRG surveys, NMFS has authorized Level A take for this species and 
other high-frequency cetaceans. SELC advised that it is arbitrary for 
the agency to impose less precautionary measures for this area that is 
home to a number of mid- and high-frequency hearing specialists which 
may be vulnerable to Level A take.
    Response: The calculated Level A harassment zone for high-frequency 
cetaceans, including harbor porpoises are extremely small measuring at 
a maximum of 54.2 m when the Geo Marine Dual 400 Sparker is in use. The 
shutdown zone in the final IHA for harbor porpoise and most other 
marine mammal species is 100 m when the sparker is the largest source 
in use and 25 m when the boomer is the largest source in use.
    SELC erroneously noted that NMFS had authorized Level A take for 
harbor porpoises and other high-frequency cetaceans in a previous IHA 
(83 FR 22443, May 15, 2018). NMFS acknowledges that the potential for 
auditory injury (Level A harassment) for high frequency species was 
discussed in that notice. Take by Level A harassment was requested by 
the applicant out of an abundance of caution and NMFS did propose 
limited take. However, the Federal Register notice referenced by SELC 
was a proposed IHA (83 FR 22443, May 15, 2018). In that notice, the 
Level A harassment isopleth for a single device (Innomar SES-2000 
Medium Sub-Bottom Profiler) had been incorrectly categorized as an 
impulsive source and resulted in a 75-m injury zone. In the Federal 
Register final notice of issuance (83 FR 36560; July 30, 2018) NMFS 
correctly described the device as being a non-impulsive sound which 
resulted in an injury zone of less than 5 m for the sub-bottom profiler 
and a maximum Level A harassment isopleth of less than 10 m for all 
other equipment. NMFS declined to authorize Level A take due to the 
small Level A harassment zone size and determined that take by Level A 
harassment was so unlikely as to be discountable.
    SELC also asserted that mid-frequency cetaceans could be exposed to 
sound levels that could result in take by Level A harassment. However, 
Level A harassment isopleths for mid-frequency cetaceans are usually 
smaller than those for high-frequency cetaceans. This is because high-
frequency cetaceans have a lower overall permanent threshold shift 
(PTS) onset threshold while both high-frequency and mid-frequency 
cetaceans, in terms of weighting, are susceptible to similar 
frequencies.
    Comment 23: SELC recommended that the potential for vessel strikes 
should be included in NMFS' take analysis since they can result in 
Level A harassment in the form injury or mortality.
    Response: NMFS does not anticipate or authorize takes associated 
with vessel strike. NMFS has imposed a suite of measures in this IHA to 
reduce the risk of vessel strikes. The occurrence of vessel strike 
during surveys is extremely unlikely based on the typical vessel speed 
of 4 knots (7.4 km/hour) while transiting survey lines. Furthermore, no 
documented vessel strikes have occurred for any HRG surveys which were 
issued IHAs from NMFS. Given the existing requirements and the lack of 
previous documented strikes from these activities, the likelihood of a 
vessel strike occurring is considered so low as to be discountable.
    Comment 24: SELC recommended that NMFS require the implementation 
of seasonal and temporal restrictions on site characterization 
activities that have the potential to injure or harass the North 
Atlantic right whale from November 1 through April 30.
    Response: NMFS is concerned about the status of the North Atlantic 
right whale population given that a UME has been in effect for this 
species since June of 2017 and that there have been a number of recent 
mortalities. NMFS appreciates the value of seasonal restrictions under 
certain circumstances. However, in this case, we have determined 
seasonal restrictions are not warranted. Given the density of right 
whales in this area, the nature of the proposed activities, and the 
required mitigation, zero takes of North Atlantic right whales are 
predicted or authorized and, therefore, additional mitigation is not 
warranted especially given the impracticability for the applicant of 
significantly shortening their work season. Additionally, Dominion is 
required to comply with restrictions associated with identified SMAs 
and they must comply with DMA restrictions, if any DMAs are established 
near the Project Area.
    Comment 25: SELC recommended that robust and effective real-time 
monitoring and mitigation systems should be utilized to protect right 
whales throughout the year.
    Response: NMFS is generally supportive of this concept. A network 
of near real-time baleen whale monitoring devices are active or have 
been tested in portions of New England and Canadian waters. These 
systems employ various digital acoustic monitoring instruments which 
have been placed on autonomous platforms including slocum gliders, wave 
gliders, profiling floats and moored buoys. Systems that have proven to 
be successful will likely see increased use as operational tools for 
many whale monitoring and mitigation applications. Responses to 
specific recommendations related to this project are included below.
    Comment 26: SELC recommended that HRG surveys should commence, with 
ramp-up, during daylight hours only, to maximize the probability that 
marine mammals are detected and confirmed clear of the exclusion zone 
(EZ).
    Response: We acknowledge the limitations inherent in detection of 
marine mammals at night. However, no injury is expected to result even 
in the absence of mitigation, given the very small estimated Level A 
harassment zones. Any potential impacts to marine mammals authorized 
for take would be limited to short-term behavioral responses. 
Restricting surveys in the manner suggested by the commenters may 
reduce marine mammal exposures by some degree in the short term, but

[[Page 55421]]

would not result in any significant reduction in either intensity or 
duration of noise exposure. The restrictions recommended by the 
commenters could result in the surveys spending increased time on the 
water, which may result in greater overall exposure to sound for marine 
mammals and increase the risk of a vessel strike; thus the commenters 
have not demonstrated that such a requirement would result in a net 
benefit. Furthermore, restricting the applicant to ramp-up only during 
daylight hours would have the potential to result in lengthy shutdowns 
of the survey equipment, which could result in the applicant failing to 
collect the data they have determined is necessary and, subsequently, 
the need to conduct additional surveys the following year. This would 
result in significantly increased costs incurred by the applicant. 
Thus, the restriction suggested by the commenters would not be 
practicable for the applicant to implement. In consideration of 
potential effectiveness of the recommended measure and its 
practicability for the applicant, NMFS has determined that restricting 
survey start-ups to daylight hours when visibility is unimpeded is not 
warranted or practicable in this case.
    Comment 27: SELC recommended NMFS should establish a standard 500-m 
EZ for all marine mammal species around surveys with noise levels that 
could result in injury or harassment of marine mammals, and, to the 
extent feasible, an extended 1,000-m EZ for North Atlantic right 
whales.
    Response: Regarding the recommendation for 500-m EZ for all marine 
mammals and 1,000-m EZ specifically for North Atlantic right whales, we 
have determined that the 500-m EZ, as required in the IHA, is 
sufficiently protective. We note that the 500-m EZ for right whales 
exceeds the modeled distance to the largest Level B harassment isopleth 
distance (100 m) by a factor of five. Additionally, the largest 
calculated Level B harassment distance for other marine mammals is 
calculated to be 100 m. Thus, we are not requiring shutdown if a North 
Atlantic right whale is sighted beyond 500-m or marine mammal is 
observed beyond 100 m.
    Comment 28: SELC questioned the efficacy of only using protected 
species observers (PSOs) to monitor exclusion zones during night 
operations. They suggested that a combination of visual monitoring and 
passive acoustic monitoring (PAM) should be used at all times that 
survey work is underway. Additionally, SELC felt that night vision or 
infrared technology should be used for efforts that continue into the 
nighttime.
    Response 29: There are several reasons why we do not agree that use 
of PAM is warranted for 24-hour HRG surveys such as the one planned by 
Dominion. While NMFS agrees that PAM can be an important tool for 
augmenting detection capabilities in certain circumstances, its utility 
in further reducing impact for Dominion's planned HRG survey activities 
is limited. First, for this activity, the area expected to be 
ensonified above the Level B harassment threshold is relatively small 
(a maximum of 100 m as described in the Estimated Take section)--this 
reflects the fact that, to start with, the source level is 
comparatively low and the intensity of any resulting impacts would also 
be low and, further, it means that inasmuch as PAM will only detect a 
portion of any animals exposed within a zone (see below), the overall 
probability of PAM detecting an animal in the harassment zone is low--
together these factors support the limited value of PAM for use in 
reducing take with smaller zones. PAM is only capable of detecting 
animals that are actively vocalizing, while many marine mammal species 
vocalize infrequently or during certain activities, which means that 
only a subset of the animals within the range of the PAM would be 
detected (and potentially have reduced impacts). Additionally, 
localization and range detection can be challenging under certain 
scenarios. For example, odontocetes are fast moving and often travel in 
large or dispersed groups which makes localization difficult. In 
addition, the ability of PAM to detect baleen whale vocalizations is 
further limited due to being deployed from the stern of a vessel, which 
puts the PAM hydrophones in proximity to propeller noise and low 
frequency engine noise which can mask the low frequency sounds emitted 
by baleen whales, including North Atlantic right whales.
    We also note that the effects to North Atlantic right whales, and 
all marine mammals, from the types of surveys authorized in this IHA 
are expected to be limited to low level behavioral harassment even in 
the absence of mitigation; no injury is expected or authorized. In 
consideration of the limited additional benefit anticipated by adding 
this detection method (especially for North Atlantic right whales and 
other low frequency cetaceans, species for which PAM has limited 
efficacy) and the cost and impracticability of implementing a full-time 
PAM program, we have determined the current requirements for visual 
monitoring are sufficient to ensure the least practicable adverse 
impact on the affected species or stocks and their habitat. Note that 
the draft IHA contained a requirement that night-vision equipment 
(i.e., night-vision goggles and infrared technology) must be available 
for use for PSOs.
    Comment 30: SELC recommended that a minimum of four PSOs, following 
a two-on/two-off schedule, are needed to provide full 360[deg] coverage 
of the exclusion zone at any given time.
    Response: NMFS does not agree with the commenters that a minimum of 
four PSOs should be required, following a two-on/two-off rotation, to 
meet the MMPA requirement that mitigation must effect the least 
practicable adverse impact upon the affected species or stocks and 
their habitat. The relatively small size of the exclusion means that 
that a single PSO stationed at the highest vantage point and engaged in 
general 360-degree scanning during daylight hours is able to 
effectively observe the necessary area. Additionally, PSOs must be on 
duty 30 minutes prior to and during nighttime ramp-ups for HRG surveys. 
The monitoring reports submitted to NMFS have indicated that the PSOs 
are able to detect marine mammals and implement appropriate mitigation 
measures, and project proponents have not exceeded take limits or 
reported unauthorized taking. In addition to the single PSO on duty 
during daylight operations, Dominion has also committed to employing a 
minimum of two NMFS-approved PSOs when HRG equipment is in use at 
night.
    Comment 31: SELC believes that shutdown requirements should not be 
waived for bottlenose dolphins belonging to any stock, but especially 
to protect the strategic and depleted stock of Western North Atlantic 
Southern Migratory Coastal bottlenose dolphin.
    Response: NMFS includes the small delphinoid waiver because 
shutdown requirements for small delphinoids under all circumstances 
represent practicability concerns without likely commensurate benefits 
for the animals in question. Small delphinoids, which would include the 
Southern Migratory Coastal stock, are commonly observed during surveys 
and would typically be the only marine mammals likely to intentionally 
approach the vessel. Auditory injury is extremely unlikely to occur for 
mid-frequency cetaceans (e.g., delphinids), as this group is relatively 
insensitive to sound produced at the predominant frequencies of HRG 
equipment while also having a relatively high threshold for the onset 
of auditory injury.

[[Page 55422]]

    A large body of anecdotal evidence indicates that small delphinoids 
commonly approach vessels during active sound production for purposes 
of bow riding, with no apparent effect observed in those delphinoids 
(e.g., Barkaszi et al., 2012). The potential for increased shutdowns 
resulting from such a measure would require Dominion to revisit any 
missed track lines to reacquire data, resulting in an overall increase 
in the total sound energy input to the marine environment and an 
increase in the total duration over which the survey is active in a 
given area. Although other mid-frequency hearing specialists (e.g., 
large delphinoids) are no more likely to incur auditory injury than are 
small delphinoids, they are much less likely to approach vessels.
    Comment 32: In order to avoid vessel strike, SELC recommended that 
all vessels operating within the Project Area should maintain a speed 
of 10 knots or less outside the period of November 1 and April 30, 
during which this speed limit should be extended to all vessels 
traveling to and from the Project Area.
    Response: NMFS does not concur with these measures. NMFS has 
analyzed the potential for ship strike resulting from Dominion's 
activity and has determined that the mitigation measures specific to 
ship strike avoidance are sufficient to avoid the potential for ship 
strike. These include: A requirement that all vessel operators comply 
with 10 knot (18.5 km/hour) or less speed restrictions in any 
established DMA or SMA; a requirement that all vessel operators reduce 
vessel speed to 10 knots (18.5 km/hour) or less when any large whale, 
any mother/calf pairs, pods, or large assemblages of non-delphinoid 
cetaceans are observed within 100 m of an underway vessel; a 
requirement that all survey vessels maintain a separation distance of 
500-m or greater from any sighted North Atlantic right whale; a 
requirement that, if underway, vessels must steer a course away from 
any sighted North Atlantic right whale at 10 knots or less until the 
500-m minimum separation distance has been established; and a 
requirement that, if a North Atlantic right whale is sighted in a 
vessel's path, or within 500 m of an underway vessel, the underway 
vessel must reduce speed and shift the engine to neutral. We have 
determined that the ship strike avoidance measures are sufficient to 
ensure the least practicable adverse impact on species or stocks and 
their habitat. Furthermore, no documented vessel strikes have occurred 
for any HRG surveys which were issued IHAs from NMFS.
    Comment 33: SELC suggested that NMFS should consider requiring that 
a DMA become active anytime a single North Atlantic right whale is 
sighted or acoustically detected, not just an aggregation of three or 
more whales.
    Response: DMAs are a component of the 2008 NOAA Ship Strike Rule to 
minimize lethal ship strikes of North Atlantic right whales. Note that 
the trigger of three or more whales is taken from a NOAA Northeast 
Fisheries Science Center (NEFSC) analysis of sightings data from Cape 
Cod Bay and Stellwagen Bank from 1980 to 1996 (Clapham & Pace 2001). 
This analysis found that an initial sighting of three or more North 
Atlantic right whales was a reasonably good indicator that whales would 
persist in the area, and the average duration of the whale's presence 
based on these sightings data was two weeks.

Changes From the Proposed IHA to Final IHA

    NMFS made several minor technical edits that that did not alter the 
number of estimated takes or the size of harassment zones. The take 
estimates and zone sizes contained in the proposed IHA are identical to 
those included in the issued IHA. NMFS made the following changes from 
the proposed IHA:
     Revised the source level for the EdgeTech 216 Chirp to 179 
dB re 1 [mu]Pa rms down from 193 dB re 1 [mu]Pa rms based on data from 
Crocker and Fratantonio (2016);
     Revised the source level for the EdgeTech 512i Chirp to 
179 dB re 1 [mu]Pa rms up from 177 dB re 1 [mu]Pa rms based on data 
from Crocker and Fratantonio (2016);
     Revised the source level of the Sonardyne Ranger 2 to 194 
dB re 1 [mu]Pa rms up from 188 dB re 1 [mu]Pa rms based on 
manufacturers data;
     Changed the primary operating frequency of the Innomar SBP 
from 2-22 kHz to 85-115kHz;
     Employed the User Spreadsheet to correct Level A 
harassment isopleths for high-frequency cetaceans in Table 5 for the 
Edgetech 216 and Edgetech 512i;
     Revised the Level B harassment isopleths for the Sonardyne 
Ranger 2, EdgeTech 216, and Edgetech512i which are included in Table 6;
     NMFS revised the EdgeTech 4200 side-scan sonar system 
operating frequencies to 300 kHz and 600 kHz; and
     Added information regarding the harassment isopleths of 
subsea positioning systems to (Sonardyne USBL, Evologics 82CR, and 
ixBlue Gaps) to Table 5 and Table 6.
    The number of Dominion survey vessels operating concurrently has 
been revised from two in the proposed IHA to four in the final IHA. 
However, the number of vessel days (161) and trackline distance per day 
(121.54 km) remains unchanged. There are no differences between the 
effects analysis NMFS conducted in the proposed and final IH. The 
number of authorized takes by Level B harassment in the issued IHA is 
the same as estimated for the propsed IHA.

Description of Marine Mammals in the Area of Specified Activities

    Sections 3 and 4 of the 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's Stock Assessment Reports (SARs; https://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's 
website (https://www.fisheries.noaa.gov/find-species).
    Table 2 lists all species or stocks for which take is expected and 
authorized for this action, and summarizes information related to the 
population or stock, including regulatory status under the MMPA and ESA 
and potential biological removal (PBR), where known. For taxonomy, we 
follow Committee on Taxonomy (2019). 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's SARs). While no mortality is anticipated or authorized here, PBR 
and annual serious injury and mortality from anthropogenic sources are 
included here as gross indicators 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's 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's U.S. Atlantic SARs (Hayes et al.

[[Page 55423]]

2020). All values presented in Table 2 are the most recent available at 
the time of publication and are available in the 2019 Atlantic and Gulf 
of Mexico Marine Mammal Stock Assessments available online at: 
www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessment-reports-region.

                          Table 2--Marine Mammals Known To Occur in the Survey Area That May Be Affected by Dominion's Activity
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                               ESA/MMPA       Stock abundance
                                                                                status;       (CV, Nmin, most     Predicted abundance             Annual
           Common name              Scientific name           Stock         strategic  (Y/    recent abundance          (CV) \3\          PBR      M/SI
                                                                                N) \1\           survey)\2\                                        \4\
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                          Order Cetartiodactyla--Cetacea--Superfamily Mysticeti (baleen whales)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Family Balaenidae:
    North Atlantic Right whale..  Eubalaena glacialis  Western North        E/D; Y          428 (0; 418; n/a)..  * 535 (0.45).........      0.8     5.55
                                                        Atlantic (WNA).
Family Balaenopteridae
 (rorquals):
    Humpback whale..............  Megaptera            Gulf of Maine......  -/-; N          1396 (0; 1380; n/a)  * 1,637 (0.07).......       22     12.5
                                   novaeangliae.
    Fin whale...................  Balaenoptera         WNA................  E/D; Y          7,418 (0.25; 6,025;  4,633 (0.08).........       12     2.35
                                   physalus.                                                 n/a).
    Sei whale...................  Balaenoptera         Nova Scotia........  E/D; Y          6,292 (1.015;        * 717 (0.30).........      6.2        1
                                   borealis.                                                 3,098; n/a).
    Minke whale.................  Balaenoptera         Canadian East Coast  -/-; N          24,202 (0.3;         * 2,112 (0.05).......    1,189        8
                                   acutorostrata.                                            18,902; n/a).
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                            Superfamily Odontoceti (toothed whales, dolphins, and porpoises)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Family Physeteridae:
    Sperm whale.................  Physeter             NA.................  E, D,Y          4,349 (0.28, 3,451;  5,353 (0.12).........      6.9        0
                                   macrocephalus.                                            n/a).
Family Delphinidae:
    Short-finned pilot whale....  Globicephala         WNA................  -/-; Y          28,924 (0.24;        18,977 (0.11) \5\....      236      160
                                   macrorhynchus.                                            23,637; 2011).
    Long-finned pilot whale.....  Globicephala melas.  WNA................  -/-; Y          39,215 (0.3;         .....................      306       21
                                                                                             30,627; n/a).
    Bottlenose dolphin..........  Tursiops truncatus.  WNA Offshore.......  -/-; N          62,851 (0.23;        97,476 (0.06) \5\....      519       28
                                                                                             15,914; 2011).
                                                       WNA Southern         -/-; Y          3,751 (0.06; 2,353;  .....................       23   0-14.3
                                                        Migratory Coastal.                   n/a).
    Common dolphin..............  Delphinus delphis..  WNA................  -/-; N          172,825 (0.21;       86,098 (0.12)........    1,452      419
                                                                                             145,216;2011).
    Atlantic white-sided dolphin  Lagenorhynchus       WNA................  -/-; N          92,233 (0.71;        37,180 (0.07)........      544       26
                                   acutus.                                                   54,443; n/a).
    Atlantic spotted dolphin....  Stenella frontalis.  WNA................  -/-: N          39,921 (0.27;        55,436 (0.32)........      303     54.3
                                                                                             32,032; 2012).
    Risso's dolphin.............  Grampus griseus....  WNA................  -/-; N          35,493 (0.19;        7,732 (0.09).........      126     49.7
                                                                                             30,289; 2011).
Family Phocoenidae (porpoises):
    Harbor porpoise.............  Phocoena phocoena..  Gulf of Maine/Bay    -/-; N          95,543 (0.31;        45,089 (0.12)........      851     2175
                                                        of Fundy.                            74,034; 2011).
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                         Order Carnivora--Superfamily Pinnipedia
--------------------------------------------------------------------------------------------------------------------------------------------------------
Family Phocidae:
    Harbor seal.................  Phoca vitulina.....  WNA................  -/-; N          75,834 (0.15,        .....................    2,006      350
                                                                                             66,884; 2012).
    Gray seal \6\...............  Halichoerus grypus.  WNA................  -/-; N          27,131 (0.19,        .....................    1,389    5,410
                                                                                             23,158, n/a).
--------------------------------------------------------------------------------------------------------------------------------------------------------
1 Endangered Species Act (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 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 NMFS marine mammal stock assessment reports online at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessment-reports-region/. CV is coefficient of variation; Nmin is the minimum estimate of stock abundance. In some cases, CV is not applicable.
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 These values, found in NMFS's SARs, represent annual levels of human-caused mortality plus serious injury from all sources combined (e.g., commercial
  fisheries, ship strike). Annual M/SI often cannot be determined precisely and is in some cases presented as a minimum value or range.
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, 2017, 2018, 2020) 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, 2017, 2018) produced density models to genus level
  for Globicephala spp. and produced a density model for bottlenose dolphins that does not differentiate between offshore and coastal stocks.
6 NMFS stock abundance estimate applies to U.S. population only, actual stock abundance including Canada is approximately 505,000. The referenced PBR
  value applies only to the U.S. population and is therefore an underestimate for the stock as a whole.

    As indicated above, all 16 species (with 17 managed stocks) in 
Table 2 temporally and spatially co-occur with the activity to the 
degree that take is reasonably likely to occur in the absence of 
mitigation measures. A detailed description of the species for which 
take has been authorized, including brief introductions to the relevant 
stocks as well as available information regarding population trends and 
threats, and information regarding local occurrence, were provided in 
the Federal Register notice for the proposed IHA (85 FR 36537; June 17, 
2020); since that time, we are not aware of any changes in the status 
of these species and stocks; therefore, detailed descriptions are not

[[Page 55424]]

provided here. Please refer to that Federal Register notice for these 
descriptions. Please also refer to NMFS' website (https://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 Dominion's survey activities 
have the potential to result in take of marine mammals by harassment in 
the vicinity of the Survey Area. The Federal Register notice for the 
proposed IHA (85 FR 36537; June 17, 2020) included a discussion of the 
effects of anthropogenic noise 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 (85 FR 36537; June 17, 2020).

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 be by Level B harassment only in the form of 
disruption of behavioral patterns for individual marine mammals 
resulting from exposure to HRG sources. Based on the nature of the 
activity and the anticipated effectiveness of the mitigation measures 
(i.e., EZs and shutdown measures), discussed in detail below in the 
Mitigation section, Level A harassment is neither anticipated nor 
authorized.
    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 authorized take.

Acoustic Thresholds

    Using the best available science, NMFS has developed acoustic 
thresholds that identify the RL of underwater sound above which exposed 
marine mammals would be reasonably expected to be behaviorally harassed 
(equated to Level B harassment) or to incur permanent threshold shift 
(PTS) of some degree (equated to Level A harassment).
    Level B Harassment for non-explosive sources--Though significantly 
driven by RL, 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 RL 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 RLs of 120 dB re 1 [mu]Pa (rms) 
for continuous (e.g., vibratory pile-driving, drilling) and above 160 
dB re 1 [mu]Pa (rms) for non-explosive impulsive (e.g., seismic 
airguns) or intermittent (e.g., scientific sonar) sources.
    Dominion's planned activity includes the use of intermittent 
(geophysical survey equipment) sources, and therefore the 160 dB re 1 
[mu]Pa (rms) threshold is applicable.
    Level A harassment for non-explosive sources--NMFS' Technical 
Guidance for Assessing the Effects of Anthropogenic Sound on Marine 
Mammal Hearing (Version 2.0) (NMFS, 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 Dominion's planned activity that may result in the 
take of marine mammals include the use of both impulsive and non-
impulsive sources (geophysical survey equipment).
    These thresholds are provided in Table 3 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 
https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-acoustic-technical-guidance.

                     Table 3--Thresholds Identifying the Onset of Permanent Threshold Shift
----------------------------------------------------------------------------------------------------------------
                                                     PTS onset acoustic thresholds * (received level)
             Hearing group              ------------------------------------------------------------------------
                                                  Impulsive                         Non-impulsive
----------------------------------------------------------------------------------------------------------------
Low-Frequency (LF) Cetaceans...........  Cell 1: Lpk,flat: 219 dB;   Cell 2: LE,LF,24h: 199 dB.
                                          LE,LF,24h: 183 dB.
Mid-Frequency (MF) Cetaceans...........  Cell 3: Lpk,flat: 230 dB;   Cell 4: LE,MF,24h: 198 dB.
                                          LE,MF,24h: 185 dB.
High-Frequency (HF) Cetaceans..........  Cell 5: Lpk,flat: 202 dB;   Cell 6: LE,HF,24h: 173 dB.
                                          LE,HF,24h: 155 dB.
Phocid Pinnipeds (PW) (Underwater).....  Cell 7: Lpk,flat: 218 dB;   Cell 8: LE,PW,24h: 201 dB.
                                          LE,PW,24h: 185 dB.
Otariid Pinnipeds (OW) (Underwater)....  Cell 9: Lpk,flat: 232 dB;   Cell 10: LE,OW,24h: 219 dB.
                                          LE,OW,24h: 203 dB.
----------------------------------------------------------------------------------------------------------------
* Dual metric acoustic thresholds for impulsive sounds: Use whichever results in the largest isopleth for
  calculating PTS onset. If a non-impulsive sound has the potential of exceeding the peak sound pressure level
  thresholds associated with impulsive sounds, these thresholds should also be considered.

[[Page 55425]]

 
Note: Peak sound pressure (Lpk) has a reference value of 1 [micro]Pa, and cumulative sound exposure level (LE)
  has a reference value of 1[micro]Pa\2\s. In this Table, thresholds are abbreviated to reflect American
  National Standards Institute standards (ANSI 2013). However, peak sound pressure is defined by ANSI as
  incorporating frequency weighting, which is not the intent for this Technical Guidance. Hence, the subscript
  ``flat'' is being included to indicate peak sound pressure should be flat weighted or unweighted within the
  generalized hearing range. The subscript associated with cumulative sound exposure level thresholds indicates
  the designated marine mammal auditory weighting function (LF, MF, and HF cetaceans, and PW and OW pinnipeds)
  and that the recommended accumulation period is 24 hours. The cumulative sound exposure level thresholds could
  be exceeded in a multitude of ways (i.e., varying exposure levels and durations, duty cycle). When possible,
  it is valuable for action proponents to indicate the conditions under which these acoustic thresholds will be
  exceeded.

Ensonified Area

    Here, we describe operational and environmental parameters of the 
activity that will feed into identifying the area ensonified above the 
acoustic thresholds, which include source levels and transmission loss 
coefficient.
    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 mobile sources such as survey vessels 
operating HRG equipment, the User Spreadsheet predicts the closest 
distance at which a stationary animal would not incur PTS if the sound 
source traveled by the animal in a straight line at a constant speed. 
Inputs used in the User Spreadsheet are shown in Table 4 and the 
resulting Level A harassment isopleths are reported below in Table 5.
    Note that NMFS considers the data provided by Crocker and 
Fratantonio (2016) to represent the best available information on 
source levels associated with HRG equipment and therefore recommends 
that source levels provided by Crocker and Fratantonio (2016) be 
incorporated in the method described above to estimate isopleth 
distances to the Level B harassment threshold. In cases when the source 
level for a specific type of HRG equipment is not provided in Crocker 
and Fratantonio (2016), NMFS recommends that either the source levels 
provided by the manufacturer be used, or, in instances where source 
levels provided by the manufacturer are unavailable or unreliable, a 
proxy from Crocker and Fratantonio (2016) be used instead. Table 1 
shows the HRG equipment types that may be used during the planned 
surveys, the sound levels associated with those HRG equipment types, 
and the literature sources for the sound source levels contained in 
Table 4.

                                                                                Table 4--User Spreadsheet Inputs
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
          HRG system                        Subsea positioning/USBL                Multibeam        Side scan      Parametric        Non-parametric SBP           Medium-penetration seismic
-------------------------------------------------------------------------------   echosounder         sonar           SBP      -----------------------------------------------------------------
                                                                               ------------------------------------------------                                                      Applied
                                   Sonardyne                                                                                     Edgetech 216   Edgetech 512   Geo Marine Dual    Acoustics  S-
         HRG equipment             Ranger 2     Evologics 82CR    IxBlue Gaps    R2 Sonics 2026   Edgetech 4200   Innomar SES-      Chirp          Chirp        400 GeoSource     Boom (Triple
                                                                                                 dual frequency       2000                                      Sparker 800j      Plate Boomer)
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Spreadsheet Tab Used..........                                         D.1: MOBILE SOURCE: Non-Impulsive, Intermittent
                                F.1: MOBILE SOURCE: Impulsive,
                                          Intermittent
                               -----------------------------------------------------------------------------------------------------------------------------------------------------------------
Source Level..................  194 RMS.......  178 RMS.......  191 RMS.......  191 RMS........  206 RMS.......  241 RMS......  179 RMS......  179 RMS......  200 RMS/210 PK..  203 RMS/213 PK
Weighting Factor Adjustment     35/55.........  48/78.........  20/30.........  170............  300,600.......  2/22.........  2/16.........  0.5/12.......  0.25/4..........  0.5
 (kHz).
Source Velocity (m/sec).......  2.045.........  2.045.........  2.045.........  2.045..........  2.045.........  2.045........  2.045........  2.045........  2.045...........  2.045
Pulse Duration (seconds)......  0.001.........  0.6...........  0.011.........  0.01115........  0.01..........  0.001........  0.001........  0.02.........  0.0008..........  0.01
1/repetition rate-(seconds)...  0.33..........  1.............  1.............  0.016667.......  0.125.........  2............  0.25.........  0.25.........  0.55............  0.25
Propagation (xLogR)...........  20............  20............  20............  20.............  20............  20...........  20...........  20...........  20..............  20
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------


        Table 5--Distances (meters) to Level A Harassment Regulatory Thresholds by Equipment Category \1\
----------------------------------------------------------------------------------------------------------------
                                                                  Marine mammal group PTS onset
                                                ----------------------------------------------------------------
                                                      LF           MF           HF         Phocid      Otariid
          HRG system            Representative    cetaceans    cetaceans    cetaceans    pinnipeds    pinnipeds
                                 HRG equipment  ----------------------------------------------------------------
                                                    199 dB       198 dB       173 dB       201 dB       219 dB
                                                    SELcum       SELcum       SELcum       SELcum       SELcum
----------------------------------------------------------------------------------------------------------------
Subsea positioning/USBL......  Sonardyne Ranger            0            0          0.1            0            0
                                2 USBL.
                               EvoLogics S2CR..            0            0          2.9            0            0
                               IxBlue Gaps.....            0            0          1.0            0            0
Multibeam Echosounder........  R2Sonics 2026...            0            0         14.4            0            0
Synthetic Aperture Sonar,      Kraken Aquapix            N/A          N/A          N/A          N/A          N/A
 combined bathymetry/sidescan.  \2\.
Sidescan Sonar...............  Edgetech 4200             N/A          N/A          N/A          N/A          N/A
                                dual Frequency
                                \2\.
Parametric SBP...............  Innomar SES-2000         12.1         14.7        3,950          4.8          0.1
                                Medium 100.

[[Page 55426]]

 
Non-Parametric SBP...........  Edgetech 216                0            0          0.0            0            0
                                Chirp.
                               Edgetech 512                0            0           0.            0            0
                                Chirp.
Medium Penetration Seismic...  Geo Marine Dual           0.1            0          1.5          0.1            0
                                400 Sparker
                                800J.
                               Applied                   5.9          0.2         54.2          3.5          0.1
                                Acoustics S-
                                Boom (Triple
                                Plate Boomer
                                1000J).
----------------------------------------------------------------------------------------------------------------
\1\ Distances to the Level A harassment threshold based on the larger of the dual criteria (peak SPL and SELcum)
  are shown.
\2\ Operating frequency above 180 kHz exceeding upper range of marine mammal hearing.

    Note that take of marine mammals through use of the non-impulsive, 
intermittent sources shown in Table 4, such as the Innomar SES-2000 
Medium 100 device, is highly unlikely. See estimated Level B harassment 
isopleth distances in Table 6. The estimated Level A harassment 
isopleths (Table 5) are based on the best currently available tools and 
information, but given aspects of these sources' output (e.g. beam 
width) that cannot readily be accounted for in the user guidance 
spreadsheet, zones calculated utilizing the spreadsheet are likely 
significant overestimates and should not be interpreted literally. 
Isopleths calculated using the User Spreadsheet are provided only as a 
reference, and in fact the area ensonified by narrower-beamed 
directional sources would be proportionally much smaller than that of a 
omni-directional or near-omnidirectional source with an isopleth of the 
same size as calculated by the User spreadsheet. As explained, NMFS 
includes qualitative consideration of beam-width and to assess the 
likely risk posed through use of these sources when evaluating 
potential for Level A harassment. HRG devices that feature low source 
levels, narrow beams, downward-directed transmission, short pulse 
lengths, frequencies outside known marine mammal hearing ranges, or 
some combination of those factors are generally considered at low risk 
of causing PTS. In consideration of the foregoing, and in consideration 
of the required mitigation measures (see the Mitigation section for 
more detail), the likelihood of the planned survey resulting in take in 
the form of Level A harassment is considered so low as to be 
discountable; therefore, NMFS did not authorize take of any marine 
mammals by Level A harassment.
    NMFS has developed an interim methodology for determining the rms 
sound pressure level (SPLrms) at the 160-dB isopleth for the 
purposes of estimating take by Level B harassment resulting from 
exposure to HRG survey equipment that takes into account source level, 
beamwidth, water depth, absorption, and operating frequency (NMFS 
2019). Distances to the behavioral threshold are shown in Table 6.

                  Table 6--HRG Equipment--Distances to Regulatory Level B Harassment Thresholds
----------------------------------------------------------------------------------------------------------------
                                                                  Source level (SLRMS)   Lateral distance (m) to
                     HRG survey equipment                           (dB re 1[mu]Pa)      Level B thresholds used
                                                                                             in take analysis
----------------------------------------------------------------------------------------------------------------
Sonardyne Ranger 2 USBL.......................................                      194                       30
EvoLogics S2CR................................................                      178                      8.0
IxBlue Gaps...................................................                      191                     34.4
R2Sonics 2026.................................................                      191                      0.3
Kraken Aquapix \1\............................................                      N/A                      N/A
Edgetech 4200 dual frequency \1\..............................                      N/A                      N/A
Innomar SES-2000 Medium 100...................................                      241                      0.7
Edgetech 216 Chirp............................................                      179                      1.9
Edgetech 512 Chirp............................................                      179                      3.1
Geo Marine Dual 400 Sparker 800J..............................                      200                    100.0
Triple Plate Boomer 1000J.....................................                      203                     21.9
----------------------------------------------------------------------------------------------------------------
\1\ Operating frequency above 180 kHz, above upper range of marine mammal hearing

Take Calculation and Estimation

    Here we describe how the information provided above is brought 
together to produce a quantitative take estimate.
    In order to estimate the number of marine mammals predicted to be 
exposed to sound levels that would result in harassment, radial 
distances to predicted isopleths corresponding to harassment thresholds 
are calculated, as described above. Those distances are then used to 
calculate the area(s) around the HRG survey equipment predicted to be 
ensonified to sound levels that exceed harassment thresholds. The area 
estimated to be ensonified to relevant thresholds in a single day is 
then calculated, based on areas predicted to be ensonified around the 
HRG survey equipment and the estimated trackline distance traveled per 
day by the survey vessel.
    The predominant source is the Geo Marine Dual 400 Sparker 800J (see 
Table 6), which results in the furthest distance to the Level B 
harassment criteria (160 dB rms 90% re 1 [mu]Pa) at 100.0 m (328 ft). 
This source will be employed on an estimated 152 vessel days. During an

[[Page 55427]]

additional 9 vessel days, the Triple Plate Boomer 1000J would be the 
predominant source used, with an estimated Level B harassment threshold 
of 22 m (72 ft) as the basis for determining potential take.
    The basis for the take estimate is the number of times that marine 
mammals are predicted to be exposed to sound levels in excess of Level 
B harassment criteria. Typically, this is determined by multiplying the 
zone of influence (ZOI) out to the Level B harassment criteria isopleth 
by local marine mammal density estimates and then correcting for 
seasonal use by marine mammals, seasonal duration of project-specific 
noise-generating activities, and estimated duration of individual 
activities when the maximum noise-generating activities are 
intermittent or occasional. In the absence of any part of this 
information, it becomes prudent to take a conservative approach to 
ensure the potential number of takes is not greatly underestimated. The 
estimated distance of the daily vessel trackline was determined using 
the estimated average speed of the vessel and the 24-hour operational 
period within each of the corresponding survey segments. Using the 
distance of 100.0 m (328 ft) and 22 m (72 ft) to the 160 dB Level B 
harassment isopleths for when HRG equipment is in use, the estimated 
daily vessel track of approximately 121.54 km (75.5 mi) for 24-hour 
operations, inclusive of an additional circular area to account for 
radial distance at the start and end of a 24-hour cycle, gives 
estimates of incidental take by HRG survey equipment based on the 
ensonified area around the survey equipment as depicted in Table 6.
    Based on the maximum estimated distance to the Level B harassment 
threshold of 100 m (Table 6) and the maximum estimated daily track line 
distance of 121.54 km, an area of 24.34 km\2\ would be ensonified to 
the Level B harassment threshold per day during the 152 vessel days 
that the Geo Marine Dual 400 Sparker 800J is in use. The estimated 
Level B harassment threshold of 22 m (72 ft) associated with the Triple 
Plate Boomer 1000J would ensonify 5.35 km\2\ for 9 vessel days as shown 
in Table 7.

                   Table 7--Survey Segment Distances and ZOIs at Level B Harassment Distances
----------------------------------------------------------------------------------------------------------------
                                                                     Number of       Estimated    Calculated ZOI
                         Survey segment                            active survey   distances per      per day
                                                                    vessel days      day (km)         (km\2\)
----------------------------------------------------------------------------------------------------------------
Lease Area Survey (Sparker In Use)..............................             149          121.54           24.34
Export Cable Corridor Survey (Sparker In Use)...................               3
Export Cable Corridor Survey (No Sparker In Use)................               9                            5.35
----------------------------------------------------------------------------------------------------------------

    The number of marine mammals expected to be incidentally taken per 
day is then calculated by estimating the number of each species 
predicted to occur within the daily ensonified area (animals/km\2\) by 
incorporating the estimated marine mammal densities. A summary of this 
method is illustrated in the following formula:

Estimated Take = D x ZOI x # of days

Where:

D = average species density (per km\2\) and ZOI = maximum daily 
ensonified area to relevant thresholds.

    The habitat-based density models produced by the Duke University 
Marine Geospatial Ecology Laboratory (Roberts et al. 2016, 2017, 2018, 
2020) represent the best available information regarding marine mammal 
densities in the Survey Area. The density data presented by Roberts et 
al. (2016, 2017, 2018, 2020) incorporates aerial and shipboard line-
transect survey data from NMFS and other organizations and incorporates 
data from 8 physiographic and 16 dynamic oceanographic and biological 
covariates, and controls for the influence of sea state, group size, 
availability bias, and perception bias on the probability of making a 
sighting. These density models were originally developed for all 
cetacean taxa in the U.S. Atlantic (Roberts et al. 2016). In subsequent 
years, certain models have been updated on the basis of additional data 
as well as certain methodological improvements. More information is 
available online at seamap.env.duke.edu/models/Duke-EC-GOM-2015/. 
Marine mammal density estimates in the Survey Area (animals/km\2\) were 
obtained using these model results (Roberts et al. 2016, 2017, 2018, 
2020).
    For the purposes of exposure analysis density data from Roberts et 
al. (2016, 2017, 2018) were mapped within the boundary of the Survey 
Area for each segment using geographic information systems. For each 
survey segment, the maximum densities as reported by Roberts et al. 
(2016, 2017, and 2018), were averaged by season over the survey 
duration (for spring, summer, fall and winter) for the entire HRG 
Survey Area based on the planned HRG survey schedule. The maximum 
average seasonal density within the HRG survey schedule was then 
selected for inclusion in the take calculations. Note that recently, 
these data have been updated with new modeling results and have 
included density estimates for pinnipeds (Roberts et al. 2016; 2017; 
2018). For pinnipeds, because the seasonality of, and habitat use by, 
gray seals roughly overlaps with harbor seals, the same estimated 
abundance has been applied to both gray and harbor seals.

                                                       Table 8--Total Number of Authorized Incidental Takes as a Percentage of Population
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                            Lease area             Cable route corridor (sparker     Cable route corridor (no            Adjusted totals
                                                                 --------------------------------             in use)                     sparker in use)        -------------------------------
                                                                                                 ----------------------------------------------------------------
                                                                      Average                         Average                         Average                                      Instances of
                                                                     seasonal       Calc. take       seasonal                        seasonal                          Take           take as
                                                                    density \1\        (No.)        density \1\     Calc. take      density \1\     Calc. take     authorization   percentage of
                                                                     (No./100                        (No./100          (No.)         (No./100          (No.)           (No.)       population\6\
                                                                     km[sup2])                       km[sup2])                       km[sup2])
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
North Atlantic right whale......................................       \2\ 0.078           2.816       \2\ 0.049           0.036       \2\ 0.049           0.023           \2\ 0               0
Humpback whale..................................................           0.085           3.087           0.066           0.048           0.066           0.032           \4\ 0               0
Fin whale.......................................................           0.261           9.448           0.122           0.089           0.122           0.059           \4\ 0               0
Sei whale.......................................................           0.002           0.089           0.001           0.000           0.001           0.000           \4\ 0               0
Sperm whale.....................................................           0.007           0.238           0.002           0.002           0.002           0.001           \4\ 0               0

[[Page 55428]]

 
Minke whale.....................................................           0.114           4.151           0.041           0.030           0.041           0.020           \4\ 0               0
Long-finned pilot whale \8\.....................................           0.029           1.038           0.010           0.007           0.010           0.005          \7\ 12            0.06
Short-finned pilot whale \8\....................................
Bottlenose dolphin (Offshore)...................................           18.53     \3\ 504.234           50.93       \3\ 3.719          50.932       \3\ 2.452             511            0.81
Bottlenose dolphin (Southern Migratory Coastal).................           18.53     \3\ 168.078           50.93      \3\ 33.470          50.932      \3\ 22.068             224             6.5
Common dolphin..................................................            1.84          66.797           0.613           0.447           0.613           0.295              68            0.08
Atlantic white-sided dolphin....................................            1.18          42.992           0.386           0.282           0.386           0.186              44            0.12
Spotted dolphin.................................................           0.729          26.425           0.219           0.160           0.219           0.106              27            0.05
Risso's dolphin.................................................           0.017           0.605           0.004           0.003           0.004           0.002           \7\ 6            0.08
Harbor porpoise.................................................           1.059          38.396           0.375           0.274           0.375           0.181              39            0.09
Harbor seal \5\.................................................           0.916          33.210           0.806           0.588           0.806           0.388              35            0.02
Gray Seal \5\...................................................  ..............  ..............  ..............  ..............  ..............  ..............  ..............            0.06
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Notes:
\1\ Cetacean density values from Duke University (Roberts et al. 2016, 2017, 2018).
\2\ New density estimate for North Atlantic right whales just became available (Roberts et al. 2020) that would make the calculated take closer to 6, but as indicated, given the small size of
  the Level B harassment zone and the much larger shutdown zone, we expect the mitigation to be effective in ensuring that no take of North Atlantic right whales occurs.
\3\ Density model for bottlenose dolphins (Roberts et al. 2016, 2017, 2018) does not differentiate between offshore and coastal stocks. Take estimates split based on bottlenose dolphin stock
  preferred water depths (Reeves et al. 2002; Hayes et al. 2018).
\4\ Take adjusted to 0 given expected effectiveness of mitigation to prevent take (shutdown zone encompasses Level B harassment zone). Calculated take for humpback whale=3; fin whale=10; sei
  whale=1; sperm whale=1; and minke whale=4.
\5\ Pinniped density values reported as ``seals'' and not species-specific.
\6\ Calculations of percentage of stock taken are based on the best available abundance estimate as shown in Table 2. In most cases the best available abundance estimate is provided by Roberts
  et al. (2016, 2017, 2018), when available, to maintain consistency with density estimates derived from Roberts et al. (2016, 2017, 2018). For North Atlantic right whales the best available
  abundance estimate is derived from the North Atlantic Right Whale Consortium 2019 Annual Report Card (Pettis et al. 2019). For bottlenose dolphins, Roberts et al. (2016, 2017, 2018) provides
  only a single abundance estimate and does not provide abundance estimates at the stock or species level (respectively), so abundance estimates used to estimate percentage of stock taken for
  bottlenose dolphins are derived from NMFS SARs (Hayes et al. 2019).
\7\ The number of authorized takes (Level B harassment only) for these species has been increased from the estimated take number to mean group size. Sources for mean group size estimates are
  as follows: Risso's dolphin, pilot whales (NOAA Fisheries Northeast and Southeast Fisheries Science Centers, 2019, 2018, 2017, 2016, 2015, 2014, 2013, 2012, 2011).
\8\ Density values reported as a guild for pilot whales at the genus level.

    Take is not authorized for six marine mammal species for which 
potential takes by Level B harassment were estimated based on the 
modeling approach described above: North Atlantic right, humpback, fin, 
sei, sperm, and minke whale. Though the modeling resulted in estimates 
of take for these species as shown in Table 8, take of these species 
are expected to be avoided due to mitigation.
    Note that the number of authorized takes (Level B harassment only) 
for Risso's dolphin and pilot whales has been increased from the 
estimated take number to mean group size. (NOAA Fisheries Northeast and 
Southeast Fisheries Science Centers, 2019, 2018, 2017, 2016, 2015, 
2014, 2013, 2012, 2011).
    For bottlenose dolphin densities, Roberts et al. (2016, 2017, and 
2018) does not differentiate by individual stock. Given the southern 
coastal migratory stock propensity to be found shallower than the 25-m 
(82-ft) depth isobath north of Cape Hatteras (Reeves et al. 2002; Hayes 
et al. 2018) and only during the summer, the export cable corridor 
segment was roughly divided along the 25-m (82-ft) depth isobath. 
Roughly 90 percent of the cable corridor is 25 m (82 ft) or less in 
depth. The Lease Area is mostly located within depths exceeding 25 m 
(82 ft), where the southern coastal migratory stock would be unlikely. 
Roughly 25 percent of the Lease Area survey segment is 25 m (82 ft) or 
less in depth. Therefore, to account for the potential for mixed stocks 
within the export cable corridor, 90 percent of the estimated take 
calculation is applied to the southern coastal migratory stock and the 
remaining applied to the offshore migratory stock within the export 
cable corridor Survey Area. Within the Lease Area, 25 percent of the 
estimated take calculation is applied to the southern coastal migratory 
stock and the remaining applied to the offshore migratory stock.
    Roberts et al. (2018) produced density models for all seals and did 
not differentiate by seal species. The take calculation methodology as 
described above resulted in an estimate of 35 total seal takes. An even 
split of takes between harbor and gray seals (i.e., 18 harbor seal 
takes and 17 gray seal takes) is authorized, based on an assumption 
that the likelihood of take of either species is equal.
    In the instance of the North Atlantic right whale, Dominion will 
implement and monitor and implement a 500-m (1,640-ft) EZ that exceeds 
the distance to the Level B harassment isopleth. Given that the 
mitigation effectively prevents Level B harassment, take has been 
adjusted to zero individuals. In addition, Dominion will implement and 
monitor and implement a 100-m (328-ft) EZ to be implemented for all 
non-delphinid large cetaceans, which is expected to preclude potential 
interactions with humpback, fin, sei, sperm, and minke whales. 
Therefore, the low calculated take estimates for these large whales was 
adjusted to zero individuals for these species and NMFS is not 
authorizing take of these whale species. Although survey activities 
will occur at night, two PSO will be on duty during night-time surveys 
and large whales are generally more easy to detect (including at night) 
than other smaller marine mammals with less pronounced blows.

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 the 
activity, and other means of effecting the least practicable impact on 
the species or stock and its habitat, paying particular attention to 
rookeries, mating

[[Page 55429]]

grounds, and areas of similar significance, and on the availability of 
the 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 the 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, impact on 
operations, and, in the case of a military readiness activity, 
personnel safety, practicality of implementation, and impact on the 
effectiveness of the military readiness activity.
    Marine mammal EZs must be established around the HRG survey 
equipment and monitored by PSOs during HRG surveys as follows:
     500-m EZ is required for North Atlantic right whales;
     During use of the GeoMarine Dual 400 Sparker 800J, a 100-m 
EZ is required for all other marine mammals except delphinid(s) from 
the genera Delphinus, Lagenorhynchus, Stenella or Tursiops and seals;
     When only the Triple Plate Boomer 1000J is in use, a 25-m 
EZ is required for all other marine mammals except delphinid(s) from 
the genera Delphinus, Lagenorhynchus, Stenella or Tursiops and 
seals;200-m buffer zone is required for all marine mammals except those 
species otherwise excluded (i.e., North Atlantic right whale).
    If a marine mammal is detected approaching or entering the EZs 
during the survey, the vessel operator must adhere to the shutdown 
procedures described below. In addition to the EZs described above, 
PSOs must visually monitor a 200-m buffer zone for the purposes of pre-
clearance. During use of acoustic sources with the potential to result 
in marine mammal harassment (i.e., anytime the acoustic source is 
active, including ramp-up), occurrences of marine mammals within the 
monitoring zone (but outside the EZs) must be communicated to the 
vessel operator to prepare for potential shutdown of the acoustic 
source. The buffer zone is not applicable when the EZ is greater than 
100 m. PSOs are also required to observe a 500-m monitoring zone and 
record the presence of all marine mammals within this zone. The zones 
described above are based upon the radial distance from the active 
equipment (rather than being based on distance from the vessel itself).

Visual Monitoring

    NMFS only requires a single PSO to be on duty during daylight 
hours. Dominion must have one PSO on duty during the day and has 
committed that a minimum of two NMFS-approved PSOs must be on duty and 
conducting visual observations when HRG equipment is in use at night. 
Visual monitoring must begin no less than 30 minutes prior to ramp-up 
of HRG equipment and continue until 30 minutes after use of the 
acoustic source. PSOs must establish and monitor the applicable EZs, 
Buffer Zone and Monitoring Zone as described above. Visual PSOs must 
coordinate to ensure 360[deg] visual coverage around the vessel from 
the most appropriate observation posts, and must conduct visual 
observations using binoculars and the naked eye while free from 
distractions and in a consistent, systematic, and diligent manner. PSOs 
are required to estimate distances to observed marine mammals. It is 
the responsibility of the Lead PSO on duty to communicate the presence 
of marine mammals as well as to communicate action(s) that are 
necessary to ensure mitigation and monitoring requirements are 
implemented as appropriate. Position data must be recorded using hand-
held or vessel global positioning system (GPS) units for each confirmed 
marine mammal sighting.

Pre-Clearance of the Exclusion Zones

    Prior to initiating HRG survey activities, Dominion must implement 
a 30-minute pre-clearance period. During pre-clearance monitoring 
(i.e., before ramp-up of HRG equipment begins), the Buffer Zone also 
acts as an extension of the 100-m EZ in that observations of marine 
mammals within the 200-m Buffer Zone would also preclude HRG operations 
from beginning. During this period, PSOs must ensure that no marine 
mammals are observed within 200 m of the survey equipment (500 m in the 
case of North Atlantic right whales). HRG equipment must not start up 
until this 200-m zone (or, 500-m zone in the case of North Atlantic 
right whales) is clear of marine mammals for at least 30 minutes. The 
vessel operator must notify a designated PSO of the proposed start of 
HRG survey equipment as agreed upon with the lead PSO; the notification 
time must not be less than 30 minutes prior to the planned initiation 
of HRG equipment in order to allow the PSOs time to monitor the EZs and 
Buffer Zone for the 30 minutes of pre-clearance. A PSO conducting pre-
clearance observations must be notified again immediately prior to 
initiating active HRG sources.
    If a marine mammal is observed within the relevant EZs or Buffer 
Zone during the pre-clearance period, initiation of HRG survey 
equipment must not begin until the animal(s) has been observed exiting 
the respective EZ or Buffer Zone, or, until an additional time period 
has elapsed with no further sighting (i.e., minimum 15 minutes for 
porpoises, and 30 minutes for all other species). The pre-clearance 
requirement includes small delphinoids. PSOs must also continue to 
monitor the zone for 30 minutes after survey equipment is shut down or 
survey activity has concluded.

Ramp-Up of Survey Equipment

    When technically feasible, a ramp-up procedure must be used for 
geophysical survey equipment capable of adjusting energy levels at the 
start or re-start of survey activities. The ramp-up procedure must be 
used at the beginning of HRG survey activities in order to provide 
additional protection to marine mammals near the Survey Area by 
allowing them to detect the presence of the survey and vacate the area 
prior to the commencement of survey equipment operation at full power. 
Ramp-up of the survey equipment must not begin until the relevant EZs 
and Buffer Zone has been cleared by the PSOs, as described above. HRG 
equipment must be initiated at their lowest power output and would be 
incrementally increased to full power. If any marine mammals are 
detected within the EZs or Buffer Zone prior to or during ramp-up, the 
HRG equipment must be shut down (as described below).

[[Page 55430]]

Shutdown Procedures

    If an HRG source is active and a marine mammal is observed within 
or entering a relevant EZ (as described above) an immediate shutdown of 
the HRG survey equipment is required. When shutdown is called for by a 
PSO, the acoustic source must be immediately deactivated and any 
dispute resolved only following deactivation. Any PSO on duty has the 
authority to delay the start of survey operations or to call for 
shutdown of the acoustic source if a marine mammal is detected within 
the applicable EZ. The vessel operator must establish and maintain 
clear lines of communication directly between PSOs on duty and crew 
controlling the HRG source(s) to ensure that shutdown commands are 
conveyed swiftly while allowing PSOs to maintain watch. Subsequent 
restart of the HRG equipment must only occur after the marine mammal 
has either been observed exiting the relevant EZ, or, until an 
additional time period has elapsed with no further sighting of the 
animal within the relevant EZ (i.e., 15 minutes for small odontocetes 
and seals, and 30 minutes for large whales).
    Upon implementation of shutdown, the HRG source may be reactivated 
after the marine mammal that triggered the shutdown has been observed 
exiting the applicable EZ (i.e., the animal is not required to fully 
exit the Buffer Zone where applicable) or, following a clearance period 
of 15 minutes for small odontocetes and seals and 30 minutes for all 
other species with no further observation of the marine mammal(s) 
within the relevant EZ. If the HRG equipment shuts down for brief 
periods (i.e., less than 30 minutes) for reasons other than mitigation 
(e.g., mechanical or electronic failure) the equipment may be re-
activated as soon as is practicable at full operational level, without 
30 minutes of pre-clearance, only if PSOs have maintained constant 
visual observation during the shutdown and no visual detections of 
marine mammals occurred within the applicable EZs and Buffer Zone 
during that time. For a shutdown of 30 minutes or longer, or if visual 
observation was not continued diligently during the pause, pre-
clearance observation is required, as described above.
    The shutdown requirement is waived for certain genera of small 
delphinids (i.e., Delphinus, Lagenorhynchus, Stenella, or Tursiops) 
under certain circumstances. If a delphinid(s) from these genera is 
visually detected within the EZ shutdown would not be required. If 
there is uncertainty regarding identification of a marine mammal 
species (i.e., whether the observed marine mammal(s) belongs to one of 
the delphinid genera for which shutdown is waived), PSOs must use best 
professional judgment in making the decision to call for a shutdown.
    If a species for which authorization has not been granted, or, a 
species for which authorization has been granted but the authorized 
number of takes have been met, approaches or is observed within the 
area encompassing the Level B harassment isopleth (100 m or 25 m), 
shutdown must occur.

Vessel Strike Avoidance

    Vessel strike avoidance measures include, but are not limited to, 
the following, except under circumstances when complying with these 
requirements puts the safety of the vessel or crew at risk:
     Vessel operators and crews must maintain a vigilant watch 
for all protected species and slow down, stop their vessel, or alter 
course, as appropriate and regardless of vessel size, to avoid striking 
any protected species. A visual observer aboard the vessel must monitor 
a vessel strike avoidance zone around the vessel (distances stated 
below). Visual observers monitoring the vessel strike avoidance zone 
may be third-party observers (i.e., PSOs) or crew members, but crew 
members responsible for these duties must be provided sufficient 
training to (1) distinguish protected species from other phenomena and 
(2) broadly to identify a marine mammal as a North Atlantic right 
whale, other whale (defined in this context as sperm whales or baleen 
whales other than North Atlantic right whales), or other marine mammal.
     All vessels, regardless of size, must observe a 10-knot 
speed restriction in specific areas designated by NMFS for the 
protection of North Atlantic right whales from vessel strikes: Any DMAs 
when in effect, the Norfolk SMA (from November 1 through April 30). See 
www.fisheries.noaa.gov/national/endangered-species-conservation/reducing-ship-strikes-north-atlantic-right-whales for specific detail 
regarding these areas.
     Vessel speeds must also be reduced to 10 knots or less 
when mother/calf pairs, pods, or large assemblages of cetaceans are 
observed near a vessel.
     All vessels must maintain a minimum separation distance of 
500 m from North Atlantic right whales. If a whale is observed but 
cannot be confirmed as a species other than a North Atlantic right 
whale, the vessel operator must assume that it is a North Atlantic 
right whale and take appropriate action.
     All vessels must maintain a minimum separation distance of 
100 m from sperm whales and all other baleen whales.
     All vessels must, to the maximum extent practicable, 
attempt to maintain a minimum separation distance of 50 m from all 
other protected species, with an understanding that at times this may 
not be possible (e.g., for animals that approach the vessel).
     When protected species are sighted while a vessel is 
underway, the vessel must take action as necessary to avoid violating 
the relevant separation distance (e.g., attempt to remain parallel to 
the animal's course, avoid excessive speed or abrupt changes in 
direction until the animal has left the area). If protected species are 
sighted within the relevant separation distance, the vessel must reduce 
speed and shift the engine to neutral, not engaging the engines until 
animals are clear of the area. This does not apply to any vessel towing 
gear or any vessel that is navigationally constrained.
     These requirements do not apply in any case where 
compliance would create an imminent and serious threat to a person or 
vessel or to the extent that a vessel is restricted in its ability to 
maneuver and, because of the restriction, cannot comply.
    Project-specific training is required for all vessel crew prior to 
the start of survey activities. Confirmation of the training and 
understanding of the requirements must be documented on a training 
course log sheet. Signing the log sheet will certify that the crew 
members understand and will comply with the necessary requirements 
throughout the survey activities.

Seasonal Operating Requirements

    Dominion will conduct HRG survey activities in the vicinity of the 
North Atlantic right whale Mid-Atlantic SMA near Norfolk and the mouth 
of the Chesapeake Bay. Activities conducted prior to May 1 must comply 
with the seasonal mandatory speed restriction period for this SMA 
(November 1 through April 30) for any survey work or transit within 
this area.
    Throughout all phases of the survey activities, Dominion must 
monitor NOAA Fisheries North Atlantic right whale reporting systems for 
the establishment of a DMA. If NOAA Fisheries should establish a DMA in 
the Lease Area or cable route corridor being surveyed, within 24 hours 
of the establishment of the DMA Dominion is required to work with NOAA 
Fisheries

[[Page 55431]]

to shut down and/or alter activities to avoid the DMA.
    Based on our evaluation of the applicant's measures, NMFS has 
determined that the required mitigation measures provide the means 
effecting the least practicable impact on the affected species or 
stocks and their habitat, paying particular attention to rookeries, 
mating grounds, and areas of similar significance.

Monitoring and Reporting

    In order to issue an 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).
     Mitigation and monitoring effectiveness.

Monitoring Measures

    As described above, visual monitoring must be performed by 
qualified and NMFS-approved PSOs. Dominion is required to use 
independent, dedicated, trained PSOs, meaning that the PSOs must be 
employed by a third-party observer provider, must have no tasks other 
than to conduct observational effort, collect data, and communicate 
with and instruct relevant vessel crew with regard to the presence of 
marine mammals and mitigation requirements (including brief alerts 
regarding maritime hazards), and must have successfully completed an 
approved PSO training course appropriate for their designated task. 
Dominion must provide resumes of all proposed PSOs (including 
alternates) to NMFS for review and approval prior to the start of 
survey operations.
    During survey operations (e.g., any day on which use of an HRG 
source is planned to occur), a single PSO must be on duty and 
conducting visual observations during the day on all active survey 
vessels when HRG equipment is operating. Additionally, Dominion has 
stated their intention to deploy two PSOs on duty during night 
operations. Visual monitoring must begin no less than 30 minutes prior 
to initiation of HRG survey equipment and must continue until one hour 
after use of the acoustic source ceases. PSOs would coordinate to 
ensure 360[deg] visual coverage around the vessel from the most 
appropriate observation posts, and must conduct visual observations 
using binoculars and the naked eye while free from distractions and in 
a consistent, systematic, and diligent manner. PSOs may be on watch for 
a maximum of four consecutive hours followed by a break of at least two 
hours between watches and may conduct a maximum of 12 hours of 
observation per 24-hour period. In cases where multiple vessels are 
surveying concurrently, any observations of marine mammals must would 
be communicated to PSOs on all survey vessels.
    PSOs must be equipped with binoculars and have the ability to 
estimate distances to marine mammals located in proximity to the vessel 
and/or EZ. Reticulated binoculars must be made available to PSOs for 
use as appropriate based on conditions and visibility to support the 
monitoring of marine mammals. Position data must be recorded using 
hand-held or vessel GPS units for each sighting. Observations must take 
place from the highest available vantage point on the survey vessel. 
General 360-degree scanning must occur during the monitoring periods, 
and target scanning by the PSO must occur when alerted of a marine 
mammal presence.
    During good conditions (e.g., daylight hours; Beaufort sea state 
(BSS) 3 or less), to the maximum extent practicable, PSOs must conduct 
observations when the acoustic source is not operating for comparison 
of sighting rates and behavior with and without use of the acoustic 
source and between acquisition periods. Any observations of marine 
mammals by crew members aboard any vessel associated with the survey 
must be relayed to the PSO team.
    Data on all PSO observations must be recorded based on standard PSO 
collection requirements. This includes dates, times, and locations of 
survey operations; dates and times of observations, location and 
weather; details of marine mammal sightings (e.g., species, numbers, 
behavior); and details of any observed marine mammal take that occurs 
(e.g., noted behavioral disturbances).

Reporting Measures

    Within 90 days after completion of survey activities, a final 
technical report must be provided to NMFS that fully documents the 
methods and monitoring protocols, summarizes the data recorded during 
monitoring, summarizes the number of marine mammals observed during 
survey activities (by species, when known), summarizes the mitigation 
actions taken during surveys (including what type of mitigation and the 
species and number of animals that prompted the mitigation action, when 
known), and provides an interpretation of the results and effectiveness 
of all mitigation and monitoring. Any recommendations made by NMFS must 
be addressed in the final report prior to acceptance by NMFS.
    In the event that Dominion personnel discover an injured or dead 
marine mammal, Dominion must report the incident to the OPR, NMFS and 
to the New England/Mid-Atlantic Regional Stranding Coordinator as soon 
as feasible. The report must include the following information:
     Time, date, and location (latitude/longitude) of the first 
discovery (and updated location information if known and applicable);
     Species identification (if known) or description of the 
animal(s) involved;
     Condition of the animal(s) (including carcass condition if 
the animal is dead);

[[Page 55432]]

     Observed behaviors of the animal(s), if alive;
     If available, photographs or video footage of the 
animal(s); and
     General circumstances under which the animal was 
discovered.
    In the event of a ship strike of a marine mammal by any vessel 
involved in the activities covered by the authorization, the IHA-holder 
must report the incident to OPR, NMFS and to the New England/Mid-
Atlantic Regional Stranding Coordinator as soon as feasible. The report 
must include the following information:
     Time, date, and location (latitude/longitude) of the 
incident;
     Species identification (if known) or description of the 
animal(s) involved;
     Vessel's speed during and leading up to the incident;
     Vessel's course/heading and what operations were being 
conducted (if applicable);
     Status of all sound sources in use;
     Description of avoidance measures/requirements that were 
in place at the time of the strike and what additional measures were 
taken, if any, to avoid strike;
     Environmental conditions (e.g., wind speed and direction, 
Beaufort sea state, cloud cover, visibility) immediately preceding the 
strike;
     Estimated size and length of animal that was struck;
     Description of the behavior of the marine mammal 
immediately preceding and following the strike;
     If available, description of the presence and behavior of 
any other marine mammals immediately preceding the strike;
     Estimated fate of the animal (e.g., dead, injured but 
alive, injured and moving, blood or tissue observed in the water, 
status unknown, disappeared); and
     To the extent practicable, photographs or video footage of 
the animal(s).

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).
    To avoid repetition, our analysis applies to all the species listed 
in Table 9, given that NMFS expects the anticipated effects of the 
planned survey to be similar in nature. As discussed in the Potential 
Effects of Specified Activities on Marine Mammals and Their Habitat 
section, PTS, masking, non-auditory physical effects, and vessel strike 
are not expected to occur.
    The majority of impacts to marine mammals are expected to be short-
term disruption of behavioral patterns, primarily in the form of 
avoidance or potential interruption of foraging. Marine mammal feeding 
behavior is not likely to be significantly impacted.
    Regarding impacts to marine mammal habitat, prey species are 
mobile, and are broadly distributed throughout the Survey Area and the 
footprint of the activity is small; therefore, marine mammals that may 
be temporarily displaced during survey 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 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. The HRG survey equipment itself will not 
result in physical habitat disturbance. Avoidance of the area around 
the HRG survey activities by marine mammal prey species is possible. 
However, any avoidance by prey species would be expected to be short 
term and temporary.
    The status of the North Atlantic right whale population is of 
heightened concern and, therefore, merits additional analysis. The 
Survey Area includes a biologically important migratory area for North 
Atlantic right whales (effective March-April and November-December) 
that extends from Massachusetts to Florida (LaBrecque, et al. 2015). As 
previously noted, no take of North Atlantic right whales has been 
authorized, and HRG survey operations will be required to shut down at 
500 m to further minimize any potential effects to this species. This 
is highly precautionary considering the Level B harassment isopleth for 
the largest source utilized (i.e., Geo Marine Dual 400 Sparker 800J is 
estimated to be 100 m). The fact that the spatial acoustic footprint of 
the survey is very small relative to the spatial extent of the 
available migratory habitat leads us to expect that North Atlantic 
right whale migration will not be impacted by the survey. Additionally, 
a UME for North Atlantic right whales was declared in June 2017, 
primarily due to mortality events in the Gulf of St. Lawrence region of 
Canada and around the Cape Cod area of Massachusetts. Overall, 
preliminary findings support human interactions, specifically vessel 
strikes or rope entanglements, as the cause of death for the majority 
of the North Atlantic right whales. Furthermore, these locations are 
found far to the north of the Survey Area.
    No take has been authorized for ESA-listed species including right, 
fin, sei, and sperm whales and NMFS does not anticipate that serious 
injury or mortality would occur to any species, even in the absence of 
mitigation. The planned survey is not anticipated to affect the fitness 
or reproductive success of individual animals. Since impacts to 
individual survivorship and fecundity are unlikely, the planned survey 
is not expected to result in population-level effects for any ESA-
listed species or alter current population trends of any ESA-listed 
species.
    As noted previously, elevated humpback whale mortalities have 
occurred along the Atlantic coast from Maine through Florida since 
January 2016. Of the cases examined, approximately half had evidence of 
human interaction (ship strike or entanglement). 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) remains healthy.
    Beginning in January 2017, elevated minke whale strandings have 
occurred

[[Page 55433]]

along the Atlantic coast from Maine through South Carolina, with 
highest numbers in Massachusetts, Maine, and New York. This event does 
not provide cause for concern regarding population level impacts, as 
the likely population abundance is greater than 20,000 whales. 
Additionally, elevated numbers of harbor seal and gray seal mortalities 
were first observed in July 2018 and have occurred across Maine, New 
Hampshire and Massachusetts. Based on tests conducted so far, the main 
pathogen found in the seals is phocine distemper virus although 
additional testing to identify other factors that may be involved in 
this UME are underway. 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 (350) is 
well below PBR (2,006) (Hayes et al. 2018). The population abundance of 
gray seals in the United States is in excess of 27,000 and likely 
increasing (Wood et al. 2019). The estimated abundance increases to 
505,000 when seals from Canada are included. Given that any Level B 
harassment of gray and harbor seals will be minor, short term, and 
temporary the authorized takes of gray and harbor seals would not 
exacerbate or compound the ongoing UMEs in any way.
    Direct physical interactions (ship strikes and entanglements) 
appear to be responsible for many of the UME humpback and North 
Atlantic right whale mortalities recorded. The HRG survey will require 
ship strike avoidance measures which would minimize the risk of ship 
strikes while fishing gear and in-water lines will not be employed as 
part of the survey. Furthermore, the planned activities are not 
expected to promote the transmission of infectious disease among marine 
mammals. The survey is not expected to result in the deaths of any 
marine mammals or combine with the effects of the ongoing UMEs to 
result in any additional impacts not analyzed here. NMFS is not 
authorizing take of large whales and is not authorizing take of any 
marine mammal species by serious injury, or mortality.
    The required mitigation measures are expected to reduce the number 
and/or severity of takes by giving animals the opportunity to move away 
from the sound source before HRG survey equipment reaches full energy 
and preventing animals from being exposed to sound levels that have the 
potential to result in more severe Level B harassment during HRG survey 
activities. Due to the small size of PTS zones no Level A harassment is 
anticipated or authorized.
    NMFS expects that most takes would primarily be in the form of 
short-term Level B behavioral harassment in the form of brief startling 
reaction and/or temporary vacating of the area, or decreased foraging 
(if such activity were occurring)--reactions that (at the scale and 
intensity anticipated here) are considered to be of low severity and 
with no lasting biological consequences. Since both the source and the 
marine mammals are mobile, only a smaller area would be ensonified by 
sound levels that could result in take for only a short period.
    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 is anticipated or authorized;
     No Level A harassment (PTS) is anticipated or authorized;
     Any foraging interruptions are expected to be short term 
and unlikely to be cause significantly impacts;
     Impacts on marine mammal habitat and species that serve as 
prey species for marine mammals are expected to be minimal and the 
alternate areas of similar habitat value for marine mammals are readily 
available;
     Take is anticipated to be by Level B behavioral harassment 
only consisting of brief startling reactions and/or temporary avoidance 
of the Survey Area;
     Mitigation measures, including visual monitoring and 
shutdowns, are expected to minimize the intensity of potential impacts 
to marine mammals.
    Based on the analysis contained herein of the likely effects of the 
specified activity on marine mammals and their habitat, and taking into 
consideration the implementation of the required monitoring and 
mitigation measures, NMFS finds that the total marine mammal take from 
the planned 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. When the predicted number of 
individuals to be taken is fewer than one third of the species or stock 
abundance, the take is considered to be of small numbers. For this IHA, 
take of all species or stocks is below one third of the estimated stock 
abundance (in fact, take of individuals is less than 7 percent of the 
abundance for all affected stocks). Additionally, other qualitative 
factors may be considered in the analysis, such as the temporal or 
spatial scale of the activities.
    Based on the analysis contained herein of the planned activity 
(including the required 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 the 
affected species or stocks.

Unmitigable Adverse Impact Analysis and Determination

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

Endangered Species Act

    Section 7(a)(2) of the Endangered Species Act of 1973 (ESA: 16 
U.S.C. 1531 et seq.) requires that each Federal agency insure that any 
action it authorizes, funds, or carries out is not likely to jeopardize 
the continued existence of any endangered or threatened species or 
result in the destruction or adverse modification of designated 
critical habitat. To ensure ESA compliance for the issuance of IHAs, 
NMFS consults internally whenever we propose to authorize take of 
endangered or threatened marine mammal species within NMFS 
jurisdiction. In the absence of mitigation measures, effects to North 
Atlantic right whale, fin whale, sei whale, and sperm whale could 
potentially occur. Accordingly, we requested initiation of consultation 
under section 7 of the ESA with NMFS Greater Atlantic Region (GARFO) on 
June 23, 2020, for the issuance of this IHA. NMFS GARFO has determined 
that issuance of the IHA to Dominion is not likely to adversely affect 
the North Atlantic right, fin, sei, or sperm whale or the critical 
habitat of any ESA-listed species or result in the

[[Page 55434]]

take of any marine mammals in violation of the ESA.

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 review our proposed action (i.e., the issuance of an IHA) 
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 planned action qualifies to be categorically excluded from 
further NEPA review.

Authorization

    NMFS has issued an IHA to Dominion for the potential harassment of 
small numbers of 10 marine mammal species incidental to the conducting 
marine site characterization surveys offshore of Virginia in the area 
of the Commercial Lease of Submerged Lands for Renewable Energy 
Development on the Outer Continental Shelf Offshore Virginia (Lease No. 
OCS-A-0483) and along a potential submarine cable route to landfall 
locations, provided the previously mentioned mitigation, monitoring and 
reporting requirements are followed.

    Dated: September 1, 2020.
Donna S. Wieting,
Director, Office of Protected Resources, National Marine Fisheries 
Service.
[FR Doc. 2020-19688 Filed 9-4-20; 8:45 am]
BILLING CODE 3510-22-P