Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to Gastineau Channel Historical Society Sentinel Island Moorage Float Project, Juneau, Alaska, 42837-42849 [2020-15198]

Agencies

• DEPARTMENT OF COMMERCE
• National Oceanic and Atmospheric Administration

[Federal Register Volume 85, Number 136 (Wednesday, July 15, 2020)]
[Notices]
[Pages 42837-42849]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2020-15198]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

[RTID 0648-XA116]


Takes of Marine Mammals Incidental to Specified Activities; 
Taking Marine Mammals Incidental to Gastineau Channel Historical 
Society Sentinel Island Moorage Float Project, Juneau, Alaska

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 
the Gastineau Channel Historical Society (GCHS) to incidentally harass, 
by Level B harassment only, marine mammals during construction 
activities associated with the Sentinel Island Moorage Float project 
near Juneau, Alaska.

DATES: This Authorization is effective from July 15, 2020 to September 
20, 2020.

FOR FURTHER INFORMATION CONTACT: Dwayne Meadows, Ph.D., 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.

[[Page 42838]]

    Authorization for incidental takings shall be granted if NMFS finds 
that the taking will have a negligible impact on the species or 
stock(s) and will not have an unmitigable adverse impact on the 
availability of the species or stock(s) for taking for subsistence uses 
(where relevant). Further, NMFS must prescribe the permissible methods 
of taking and other ``means of effecting the least practicable adverse 
impact'' on the affected species or stocks and their habitat, paying 
particular attention to rookeries, mating grounds, and areas of similar 
significance, and on the availability of 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 24 October 2019, NMFS received a request from GCHS for an IHA to 
take marine mammals incidental to Sentinel Island Moorage Float project 
near Juneau, Alaska. The application was deemed adequate and complete 
on February 7, 2020. GCHS's request is for take of seven species 
(consisting of eight stocks) of marine mammals by Level B harassment 
and/or Level A harassment. Neither GCHS nor NMFS expects serious injury 
or mortality to result from this activity and, therefore, an IHA is 
appropriate.

Description of the Specified Activity

Overview

    The project consists of the construction of an access float to more 
easily access Sentinel Island within Favorite Channel/Lynn Canal near 
Juneau, Alaska. GCHS would install a pile supported marine float with a 
metal gangway spanning from the float to a timber platform on Sentinel 
Island. The project includes the following in-water components: Driving 
six 24-inch diameter steel pipe piles to support the float and seaward 
end of the gangway. Pile driving would be by vibratory pile driving to 
install the piles until down-the-hole (DTH) drilling is needed to rock 
socket the piles. Impact pile driving will only be used for piles that 
encounter soils too dense to penetrate with the vibratory equipment, 
which is not expected. A detailed description of the planned project is 
provided in the Federal Register notice for the proposed IHA (85 FR 
18196; April 1, 2020). Since that time, no changes have been made to 
the planned activities. Therefore, a detailed description is not 
provided here. Please refer to that Federal Register notice for the 
description of the specific activity.

Comments and Responses

    A notice of NMFS's proposal to issue an IHA to GCHS was published 
in the Federal Register on April 1, 2020 (85 FR 18196). That notice 
described, in detail, GCHS's activity, the marine mammal species that 
may be affected by the activity, and the anticipated effects on marine 
mammals. During the 30-day public comment period, NMFS received 
comments from Defenders of Wildlife (Defenders). A comment letter from 
the Marine Mammal Commission (Commission) was received pursuant to the 
Commission's authority to recommend steps it deems necessary or 
desirable to protect and conserve marine mammals (16 U.S.C. 1402). We 
are obligated to respond to the Commission's recommendations within 120 
days, and we do so below.
    Comment: Defenders suggested that an additional local location 
where Steller sea lions aggregate is Poundstone Rock buoy which is 1.6 
miles (2.6 km) from the southern end of Sentinel Island. They assert 
the buoy is in the Level B harassment zone and request we confirm this 
and state if take would occur at this location. They also request 
Protected Species Observers (PSOs) be notified of this resting area.
    Response: We thank Defenders for noting this additional location. 
Poundstone Rock and buoy are several hundred meters to the west of the 
level B harassment zone so animals resting there would not be taken as 
a result of this project.
    Comment: Defenders requests we ground truth the data of Wade et al. 
(2016) with regard to the proportion of humpback whales of the 
Endangered Species Act (ESA) listed Mexico Distinct Population Segment 
(DPS) in southeast Alaska.
    Response: We thank Defenders for their comments. Our obligation 
under the MMPA is to issue incidental take authorizations for stocks of 
marine mammals (or species when stocks have not been assigned). The 
relevant stock in this area is the Central North Pacific stock. The 
DPSs created under the ESA are only relevant for regulatory actions 
under that law. NMFS's Alaska Regional office conducted an ESA Section 
7 consultation on this IHA which concluded that NMFS authorization of 
take of humpback whales under the MMPA is not likely to jeopardize 
continued existence of humpback whales (or any other ESA-listed 
species), and is not likely to destroy or adversely modify any critical 
habitat (specifically, western DPS Steller sea lion).
    Comment: Defenders also encourages us to reference and discuss a 
new paper by Southall et al. (2019) regarding marine mammal noise 
exposure criteria.
    Response: We appreciate Defenders comment. NMFS has reviewed the 
Southall et al. (2019) paper in the context of NMFS' 2018 Revised 
Technical Guidance. The paper recommends the same thresholds and 
weighting functions as NMFS' 2018 Technical Guidance and no changes are 
necessary in our analysis.
    Comment: The Commission recommends that NMFS convey any concerns of 
local native Alaska communities in the Federal Register notices for 
draft and final authorizations regarding subsistence use and how those 
concerns will be addressed by either the applicant or NMFS.
    Response: We agree with the Commission. In order to issue an IHA, 
NMFS must find that the specified activity will not have an 
``unmitigable adverse impact'' on the subsistence uses of the affected 
marine mammal species or stocks by Alaskan Natives. NMFS has defined 
``unmitigable adverse impact'' in 50 CFR 216.103. Sealaska Heritage 
Institute requested, and GCHS indicated that it would require the 
contractor to provide public notice 7 days in advance of the project 
and again 2 days before construction commences in the local media and 
to post information signage on the board at the Amalga Harbor boat 
launch 7 days prior to commencement of construction activities.
    Comment: The Commission recommends that for all authorizations 
involving DTH drilling, including GCHS's final IHA, NMFS (1) use source 
level data from Denes et al. (2019), its Level A harassment thresholds 
for impulsive sources, and the relevant expected operating parameters 
to estimate the extents of the Level A harassment zones, (2) use source 
level data from Denes et al. (2016) and its Level B harassment 
threshold of 120-decibels (dB) for continuous sources to estimate the 
extents of the Level B harassment zones, (3) ensure the shut-down zones 
are reasonable to minimize unnecessary delays and enable the activities 
to be completed in a timely manner, and (4) ensure that the numbers of 
Level A and B harassment takes are sufficient based on the resulting 
zones, including in GCHS's case the Level A harassment takes.
    Response: NMFS acknowledges that DTH piling operations can, but may 
not always, include both impulsive and continuous noise components. The

[[Page 42839]]

limited available data show that the specific acoustic characteristics 
of any particular DTH piling operation can vary significantly, based on 
the extent of the continuous non-pulse acoustic components of the 
drilling/pumping and the impulsive acoustic components of the 
hammering, as well as the nature of the environment (especially bottom 
characteristics). Currently, given the potential variation in the 
acoustic output from any specific operation and the limited in situ 
measurements of DTH piling available, NMFS is taking a conservative 
approach until more data are available. Specifically, we recommend 
estimating the potential impulsive components (and using the associated 
thresholds) of the operations for the purposes of predicting Level A 
harassment and estimating the potential continuous components (and 
using the associated threshold) for the purposes of predicting Level B 
harassment. As recommended, we have used the Denes et al. (2016) source 
level as a proxy source level for the purposes of the Level B 
harassment assessment. For the purposes of the Level A harassment 
assessment, while using Denes et al. (2019) may be more appropriate for 
larger pile sizes, Denes et al. (2016), which shows a single strike 
source level of 154 dB SEL, is the most relevant and appropriate source 
level for the 24-inch pile size of this project.
    We have recently received new analyses and data that provide us 
three references for source levels. For the 24-inch pile size of this 
project the most relevant source level is Denes et al. (2016), which 
new analyses show has a single strike source level of 154 dB (Sound 
Exposure Level) SEL.
    We note that it is not a simple matter to estimate the strikes per 
pile needed as input to calculate Level A harassment isopleths. DTH 
equipment varies significantly in hammer rates both within and across 
hole sizes. For example, we note that the Commission's recommendation 
of 7 to 10 strikes per second is far below values we know to be 
applicable for equipment of this size (e.g., the equipment used at Ward 
Cove (85 FR 12523; March 3, 2020), operated at 15 strikes per second). 
We further note that the Commission is under the impression that the 
appropriate pulse duration for DTH hammering is 100 milliseconds 
(msec), a standard value applied to impact hammers. There is no reason 
to assume DTH hammers have a similar pulse duration, and in fact Denes 
et al. (2019) provided data on pulse durations. We also note that Denes 
et al. (2019) used a 42-inch drill bit to drill much larger holes than 
the 24-inch drill holes of this project. The larger drill bits likely 
create louder sounds from the larger area of contact with rock, which 
means that the Level A harassment zones would be overestimated to some 
degree for this project.
    Finally, we have ensured that the shut-down zones are reasonable to 
minimize unnecessary delays and enable the activities to be completed 
in a timely manner, and that the numbers of Level A and B harassment 
takes are sufficient based on the new zones.
    Comment: The Commission recommends that NMFS encourage action 
proponents to provide the necessary operational information and 
characteristics for DTH drilling, use consistent terminology regarding 
DTH drilling in all relevant applications, and use consistent 
terminology in all future Federal Register notices and draft and final 
authorizations that involve DTH drilling.
    Response: We agree with the Commission that as knowledge of the 
variety of DTH methods and uses grows, more information from applicants 
on operational information and characteristics of DTH drills, and more 
consistent terminology, is beneficial. We note that many applicants do 
not know exactly what DTH equipment they will use at the time of 
application and that DTH equipment appears to have more variable 
operational parameters than impact or pile driving. The lack of data on 
the extremes of these operational parameters for DTH systems makes 
implementing even conservative assumptions challenging. The Commission 
could be of great service by helping to gather and publish the relevant 
information from literature and experts to increase our understanding 
of these systems.
    Comment: The Commission recommends that NMFS require all applicants 
that propose to use a DTH hammer to install piles, including GCHS, to 
conduct in-situ measurements, ensure that signal processing is 
conducted appropriately, and adjust the Level A and B harassment zones 
accordingly.
    Response: We will evaluate the need to require such measures for 
future projects on a case-by-case basis, though we acknowledge the 
general need for more data on these sources.
    Comment: The Commission recommends that NMFS (1) ensure that take 
estimates for all proposed IHAs and rulemakings and for GCHS's final 
authorization abide by its policy that an individual marine mammal can 
be taken only once on a given day and specify that policy on its web 
page, (2) increase the haulout count from 134 to 849 seals based on the 
95-percent CI for seals at CF13 and CF11 [Marine Mammal lab survey unit 
descriptors] and authorize at least 5,094 takes of harbor seals in the 
final authorization, and (3) specify that 849 individual seals could be 
taken and factor that number into the percentage of the stock taken and 
its small numbers determination.
    Response: For the purposes of predicting and authorizing take, 
NMFS' general practice is to limit the enumeration of take of 
individual marine mammals to once per day and we plan to augment our 
application instructions on the web to indicate this. For the purposes 
of monitoring impacts, we clarify the difference between takes and 
potential daily number of observations that PSOs may or may not be able 
to attribute to single individuals throughout the course of a day. We 
disagree with the Commission that take be increased for unit CF11. Unit 
CF 11 is not within the level B harassment zone and the Commission 
provided no evidence that animals from CF11 enter the Level B 
harassment zone. CF12 and CF13 areas are larger than the project area 
so, regardless of whether animals from other areas move in and out, the 
total number of animals surveyed from those areas represent a 
conservative estimate of the maximum number of individuals that might 
be present and taken during the course of a day.
    Comment: The Commission recommends that NMFS ensure GCHS keeps a 
running tally of the total takes, based on observed and extrapolated 
takes, for Level A and B harassment.
    Response: We agree that the applicant must ensure they do not 
exceed authorized takes. A condition for extrapolation of the estimated 
takes by Level B harassment based on the number of observed exposures 
within the Level B harassment zone and the percentage of the Level B 
harassment zone that was not visible is included.
    Comment: The Commission recommends that NMFS refrain from issuing 
renewals for any authorization and instead use its abbreviated Federal 
Register notice process. They further recommend that if NMFS uses 
renewals, we (1) stipulate in all Federal Register notices and 
authorizations that a renewal is a one-time opportunity and, (2) if 
NMFS refuses to stipulate a renewal being a one-time opportunity, 
explain why it will not do so. The Commission also claimed that NMFS' 
failure to address the Commission's comments and recommendations in the 
decision document runs counter to the requirements of the 
Administrative Procedures Act (APA).

[[Page 42840]]

    Response: NMFS has changed their website and templates to reflect 
that Renewals are a one-time opportunity. Regarding the recommendation 
to refrain from using the Renewal process, NMFS does not agree with the 
Commission and, therefore, does not adopt the Commission's 
recommendation. NMFS has explained the rationale for this decision in 
multiple Federal Register notices (e.g., 84 FR 52464; October 02, 
2019), nonetheless, NMFS will also provide a separate detailed 
explanation of its decision within 120 days, as required by section 
202(d) of the MMPA.
    Comment: The Commission recommended that NMFS continue to include 
in all draft and final IHAs the explicit requirements to cease 
activities if a marine mammal is injured or killed during the proposed 
activities until NMFS reviews the circumstances involving any injury or 
death that has been attributed to the activities and determines what 
additional measures are necessary to minimize additional injuries or 
deaths.
    Response: NMFS concurs with the Commission's recommendation as it 
relates to this IHA, and construction IHAs in general, and has added 
the referenced language to the Monitoring and Reporting section of this 
notice and the Reporting section of the issued IHA. We will continue to 
evaluate inclusion of this language in future IHAs.

Changes From the Proposed IHA to Final IHA

    The vibratory pile driving source level for 16 inch piles from the 
U.S. Navy (2015) was corrected to 162 dB (SPL (root mean square) rms) 
from 161 dB in the proposed rule. We clarified the actual take is 
limited to one take per animal per day, and that calculations of total 
instances of sightings per day that may initially be made by observers 
cannot exceed more than 1 take per individual per day from the known 
population in the area (See Estimated Take section for revised 
description). The condition for extrapolation of the estimated takes by 
Level B harassment based on the number of observed exposures within the 
Level B harassment zone and the percentage of the Level B harassment 
zone that was not visible was inadvertently omitted in the proposed IHA 
Federal Register notice and is now included.
    As discussed above in the Comments and Responses section, we are 
changing the approach to DTH hammering so that we estimate the 
potential impulsive components (using the associated thresholds) of the 
operations for the purposes of predicting Level A harassment and 
estimate the potential continuous components (using the associated 
threshold) for the purposes of predicting Level B harassment. We use 
the Denes et al., (2016) source level of 154 dB single strike SEL as a 
proxy source level for the purposes of the Level A harassment 
assessment and continue to use the 166.2 dB RMS) source level for Level 
B calculations. As a result new Level A harassment zones (see Estimated 
Take section below) and shutdown zones (see Mitigation section below) 
are incorporated. These new zones are smaller than the existing zones 
for impact pile driving, and since the different pile driving 
activities are likely to occur on the same day, there is no change to 
estimated take. We add the explicit requirements to cease activities if 
a marine mammal is injured or killed during the proposed activities 
until NMFS reviews the circumstances to the Monitoring and Reporting 
section of this notice and the Reporting section of the issued IHA. 
Typographical errors were corrected.

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 1 lists all species with expected potential for occurrence in 
Juneau, Alaska 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. Alaska SARs (e.g., Muto et al., 2019). All values presented 
in Table 1 are the most recent available at the time of publication and 
are available in the draft 2019 SARs (Muto et al., 2019).

                                     Table 1--Marine Mammals Potentially Present in the Vicinity of the Study Areas
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                                                                                                              Stock abundance (CV,
            Common name                 Scientific name             Stock              ESA/MMPA status;        Nmin, most recent       PBR     Annual M/
                                                                                      Strategic (Y/N) \1\    abundance survey) \2\               SI \3\
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                                          Order Cetartiodactyla--Cetacea--Superfamily Mysticeti (baleen whales)
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Family Physeteridae:
    Sperm whale....................  Physeter               North Pacific........  -; N                      N/A (see SAR, N/A,       See SAR        4.4
                                      macrocephalus.                                                          2015), see text.
Family Balaenopteridae (rorquals):
    Humpback Whale.................  Megaptera              Central North Pacific  -;N (Hawaii DPS)          10,103 (0.3, 7,890,           83         25
                                      novaeangliae.                                                           2006).
                                                            Central North Pacific  T,D,Y (Mexico DPS)        3264.................        N/A        N/A

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    Minke whale \4\................  Balaenoptera           Alaska...............  -; N                      N/A, see text........        N/A          0
                                      acutorostrata.
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                                            Superfamily Odontoceti (toothed whales, dolphins, and porpoises)
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Family Delphinidae:
    Killer whale \5\...............  Orcinus orca.........  Alaska Resident......  -; Y                      2347.................         24          1
                                                            Northern Resident....                            261..................       1.96          0
                                                            West Coast transient.                            243..................        2.4          0
Family Phocoenidae (porpoises):
    Dall's porpoise \4\............  Phocoenoides dalli...  Alaska...............  -;N                       83,400 (0.097, N/A,          N/A         38
                                                                                                              1991).
    Harbor porpoise................  Phocoena phocoena....  Southeast Alaska.....  -; Y                      975 (2012)...........        8.9         34
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                                                         Order Carnivora--Superfamily Pinnipedia
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Family Otariidae (eared seals and
 sea lions):
    Steller sea lion...............  Eumetopias jubatus...  Eastern U.S..........  -; N                      41,638 (n/a; 41,638;       2,498        108
                                                                                                              2015).
    Steller sea lion...............  Eumetopias jubatus...  Western U.S..........  E,D,Y                     54,268 (see SAR,             326        247
                                                                                                              54,267, 2017).
Family Phocidae (earless seals):
    Harbor seal....................  Phoca vitulina         Lynn Canal/Stephens    -; N                      9,478 (see SAR,              155         50
                                      richardii.             Passage.                                         8,605, 2011).
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\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 SARs online at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments. CV is
  coefficient of variation; Nmin is the minimum estimate of stock abundance. In some cases, CV is not applicable
\3\ 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 mortality/serious injury (M/SI) often cannot be determined precisely and is in some cases presented as a
  minimum value or range. A CV associated with estimated mortality due to commercial fisheries is presented in some cases.
\4\ The most recent abundance estimate is >8 years old, there is no official current estimate of abundance available for this stock.
\5\ NMFS has preliminary genetic information on killer whales in Alaska which indicates that the current stock structure of killer whales in Alaska
  needs to be reassessed. NMFS is evaluating the new genetic information. A complete revision of the killer whale stock assessments will be postponed
  until the stock structure evaluation is completed and any new stocks are identified'' (Muto, Helker et al. 2018). For the purposes of this IHA
  application, the existing stocks are used to estimate potential takes.

    All species that could potentially occur in the proposed survey 
areas are included in Table 1. As described below, seven species (with 
eight managed stocks) temporally and spatially co-occur with the 
activity to the degree that take is reasonably likely to occur, and we 
have proposed authorizing it. Sperm whales are considered extra-limital 
and will not be considered further.
    A detailed description of the species likely to be affected by the 
project, including brief introductions to the species and relevant 
stocks as well as available information regarding population trends and 
threats, and information regarding local occurrence, were provided in 
the Federal Register notice for the proposed IHA (85 FR 18196; April 1, 
2020); since that time, we are not aware of any changes in the status 
of these species and stocks; therefore, detailed descriptions are not 
provided here. Please refer to that 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 GCHS's construction activities 
have the potential to result in behavioral harassment of marine mammals 
in the vicinity of the survey area. The notice of proposed IHA (85 FR 
18196; April 1, 2020) included a discussion of the effects of 
anthropogenic noise on marine mammals and the potential effects of 
underwater noise from GCHS's activities on marine mammals and their 
habitat. That information and analysis is incorporated by reference 
into this final IHA determination and is not repeated here; please 
refer to the notice of proposed IHA (85 FR 18196; April 1, 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 primarily be by Level B harassment, as use 
of the acoustic source (i.e., vibratory or impact pile driving or DTH 
drilling) has the potential to result in disruption of behavioral 
patterns for individual marine mammals. There is also some potential 
for auditory injury (Level A harassment) to result, primarily for 
mysticetes, high frequency species and pinnipeds because predicted 
auditory

[[Page 42842]]

injury zones are larger than for mid-frequency species. Auditory injury 
is unlikely to occur for mid-frequency species and otariids. The 
proposed mitigation and monitoring measures are expected to minimize 
the severity of the taking to the extent practicable.
    As described previously, no mortality is anticipated or authorized 
for this activity. Below we describe how the take is estimated.
    Generally speaking, we estimate take by considering: (1) Acoustic 
thresholds above which NMFS believes the best available science 
indicates marine mammals will be behaviorally harassed or incur some 
degree of permanent hearing impairment; (2) the area or volume of water 
that will be ensonified above these levels in a day; (3) the density or 
occurrence of marine mammals within these ensonified areas; and, (4) 
and the number of days of activities. We note that while these basic 
factors can contribute to a basic calculation to provide an initial 
prediction of takes, additional information that can qualitatively 
inform take estimates is also sometimes available (e.g., previous 
monitoring results or average group size). Below, we describe the 
factors considered here in more detail and present the take estimate.

Acoustic Thresholds

    Using the best available science, NMFS has developed acoustic 
thresholds that identify the received level of underwater sound above 
which exposed marine mammals would be reasonably expected to be 
behaviorally harassed (equated to Level B harassment) or to incur 
Permanent Threshold Shift (PTS) of some degree (equated to Level A 
harassment).
    Level B Harassment for non-explosive sources--Though significantly 
driven by received level, the onset of behavioral disturbance from 
anthropogenic noise exposure is also informed to varying degrees by 
other factors related to the source (e.g., frequency, predictability, 
duty cycle), the environment (e.g., bathymetry), and the receiving 
animals (hearing, motivation, experience, demography, behavioral 
context) and can be difficult to predict (Southall et al., 2007, 
Ellison et al., 2012). Based on what the available science indicates 
and the practical need to use a threshold based on a factor that is 
both predictable and measurable for most activities, NMFS uses a 
generalized acoustic threshold based on received level to estimate the 
onset of behavioral harassment. NMFS predicts that marine mammals are 
likely to be behaviorally harassed in a manner we consider Level B 
harassment when exposed to underwater anthropogenic noise above 
received levels of 120 dB re 1 microPascal ([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., impact pile driving) 
or intermittent (e.g., scientific sonar) sources.
    GCHS's proposed activity includes the use of continuous (vibratory 
pile-driving and DTH drilling) and impulsive (impact pile-driving and 
DTH drilling) sources, and therefore the 120 and 160 dB re 1 [mu]Pa 
(rms) thresholds are 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) (Technical Guidance, 2018) identifies dual 
criteria to assess auditory injury (Level A harassment) to five 
different marine mammal groups (based on hearing sensitivity) as a 
result of exposure to noise from two different types of sources 
(impulsive or non-impulsive). GCHS's activity includes the use of 
impulsive (impact pile-driving) sources.
    These thresholds are provided in Table 2. 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 2--Thresholds Identifying the Onset of Permanent Threshold Shift
----------------------------------------------------------------------------------------------------------------
                                PTS onset acoustic thresholds * (received level)
-----------------------------------------------------------------------------------------------------------------
             Hearing group                        Impulsive                         Non-impulsive
----------------------------------------------------------------------------------------------------------------
Low-Frequency (LF) Cetaceans...........  Cell 1: Lpk,flat: 219 dB;   Cell 2: LE,LF,24h: 199 dB.
                                          LE,LF,24h: 183 dB.
Mid-Frequency (MF) Cetaceans...........  Cell 3: Lpk,flat: 230 dB;   Cell 4: LE,MF,24h: 198 dB.
                                          LE,MF,24h: 185 dB.
High-Frequency (HF) Cetaceans..........  Cell 5: Lpk,flat: 202 dB;   Cell 6: LE,HF,24h: 173 dB.
                                          LE,HF,24h: 155 dB.
Phocid Pinnipeds (PW) (Underwater).....  Cell 7: Lpk,flat: 218 dB;   Cell 8: LE,PW,24h: 201 dB.
                                          LE,PW,24h: 185 dB.
Otariid Pinnipeds (OW) (Underwater)....  Cell 9: Lpk,flat: 232 dB;   Cell 10: LE,OW,24h: 219 dB.
                                          LE,OW,24h: 203 dB.
----------------------------------------------------------------------------------------------------------------
* Dual metric acoustic thresholds for impulsive sounds: Use whichever results in the largest isopleth for
  calculating PTS onset. If a non-impulsive sound has the potential of exceeding the peak sound pressure level
  thresholds associated with impulsive sounds, these thresholds should also be considered.
Note: Peak sound pressure (Lpk) has a reference value of 1 [micro]Pa, and cumulative sound exposure level (LE)
  has a reference value of 1[micro]Pa\2\s. In this Table, thresholds are abbreviated to reflect American
  National Standards Institute standards (ANSI 2013). However, peak sound pressure is defined by ANSI as
  incorporating frequency weighting, which is not the intent for this Technical Guidance. Hence, the subscript
  ``flat'' is being included to indicate peak sound pressure should be flat weighted or unweighted within the
  generalized hearing range. The subscript associated with cumulative sound exposure level (SEL) 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. For DTH, as discussed above, we now estimate the potential 
impulsive components (using the associated thresholds) of DTH 
operations for the purposes of predicting Level A harassment using 
relevant impulsive source levels, and we estimate the potential 
continuous components of DTH (using the associated threshold) for the 
purposes of predicting Level B harassment using relevant continuous 
source levels.
    For vibratory pile driving we determined a source level of 162 dB 
(RMS SPL) at 10m was most appropriate. The closest known measurements 
of sound levels for

[[Page 42843]]

vibratory pile installation of 24-inch steel piles are from the U.S. 
Navy Proxy Sound Source Study for projects in Puget Sound (U.S. Navy 
2015). Based on the projects analyzed it was determined that 16- to 24-
inch piles exhibited similar sound source levels. For DTH drilling we 
use a source level of 166.2 dB (RMS SPL) for Level B harassment zones; 
this is derived from Denes et al. (2016), where they drilled 24-inch 
piles near Kodiak, AK. For Level A harassment zones for DTH drilling we 
use the single strike source level of 154 dB SEL that was recently 
calculated from the same Kodiak project. To be conservative, since DTH 
drilling and vibratory pile driving would occur on the same day, the 
applicant used the higher of the vibratory and DTH source levels (162 
dB ssSEL for level A and 166.2dB rms for level B harassment) for both 
Level A and Level B calculations and assumed all drilling/driving time 
in a day was at this higher level. For impact pile driving of 24-inch 
piles, sound measurements were used from the literature review in 
Appendix H of the Alaska Department of Transportation (AKDOT&PF) study 
(Yurk et al. 2015) for 24-inch piles driven in the Columbia River with 
a diesel impact hammer (190 dB RMS, 205 dB Peak, 175 dB SS SEL).
    We assumed no more than two piles per day with DTH drilling as the 
duration per pile was assumed to be 6 hours. For impact pile driving 
activities we also assumed no more than 2 piles per day and 250 strikes 
per pile. In all cases we used a propagation loss coefficient of 15 
logR as most appropriate for these stationary, in-shore sources.
    When the NMFS Technical Guidance (2016) was published, in 
recognition of the fact that ensonified area/volume could be more 
technically challenging to predict because of the duration component in 
the new thresholds, we developed a User Spreadsheet that includes tools 
to help predict a simple isopleth that can be used in conjunction with 
marine mammal density or occurrence to help predict takes. We note that 
because of some of the assumptions included in the methods used for 
these tools, we anticipate that isopleths produced are typically going 
to be overestimates of some degree, which may result in some degree of 
overestimate of Level A harassment take. However, these tools offer the 
best way to predict appropriate isopleths when more sophisticated 3D 
modeling methods are not available, and NMFS continues to develop ways 
to quantitatively refine these tools, and will qualitatively address 
the output where appropriate. For stationary sources, such as pile 
driving and drilling in this project, NMFS User Spreadsheet predicts 
the distance at which, if a marine mammal remained at that distance the 
whole duration of the activity, it would incur PTS. Inputs used in the 
User Spreadsheet, and the resulting isopleths are reported below.
    NMFS User spreadsheet input scenarios for vibratory pile driving/
DTH drilling and impact pile driving are shown in Table 3. These input 
scenarios lead to PTS isopleth distances (Level A thresholds) of 
anywhere from 7 to 220 meters (22 to 720 ft), depending on the marine 
mammal group and scenario (Table 4).

                                      Table 3--NMFS User Spreadsheet Inputs
----------------------------------------------------------------------------------------------------------------
                                             User spreadsheet input
-----------------------------------------------------------------------------------------------------------------
                                        Vibratory pile driving/DTH      DTH drilling--
                                           drilling--continuous           impulsive         Impact pile driving
----------------------------------------------------------------------------------------------------------------
Spreadsheet Tab Used.................  A.1) Vibratory pile driving  E.1-2) Impact pile     E.1) Impact pile
                                                                     driving.               driving.
Source Level.........................  166.2 dB RMS...............  154 dB SS SEL........  175 dB SS SEL.
Weighting Factor Adjustment (kHz)....  2.5........................  2....................  2.
a) Number of strikes per pile........  N/A........................  10,000...............  250.
a) Activity Duration (h:min) within    12:00......................  N/A..................  N/A.
 24-h period.
Propagation (xLogR)..................  15.........................  15...................  15.
Distance of source level measurement   10.........................  10...................  10.
 (meters).
Number of piles per day..............  2..........................  2....................  2.
----------------------------------------------------------------------------------------------------------------


                                       Table 4--NMFS User Spreadsheet Outputs: Level B and Level A (PTS) Isopleths
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                       PTS isopleths (meters) (level A)
                                      Behavioral     ---------------------------------------------------------------------------------------------------
            Activity              disturbance (level   Humpback + Minke                         Harbor + Dall's
                                    B) all species          whales           Killer whales         porpoise          Harbor seals      Stellar sea lions
--------------------------------------------------------------------------------------------------------------------------------------------------------
Vibratory Driving/DTH drilling--  12.1 km (7.5        80 m (263 ft).....  7 m (23 ft).......  118 m (387 ft)....  48 m (158 ft).....  4 m (13 ft).
 continuous.                       miles) *.
DTH drilling--impulsive.........  N/A...............  137 m (447 ft)....  5 m (16 ft).......  163 m (532 ft)....  73 m (239 ft).....  6 m (17 ft).
Impact Driving..................  1 km (3280 ft)....  184 m (605 ft)....  7 m (23 feet).....  220 m (720 ft)....  99 m (325 ft).....  8 m (25 ft).
--------------------------------------------------------------------------------------------------------------------------------------------------------
* Lynn Canal is smaller than this, therefore extent of actual impacts will be constrained by land.

    The distances to the Level B harassment threshold of 120 dBrms are 
12.1 kilometers (km) (7.5 miles (mi)) for vibratory pile driving/DTH 
drilling and 1 km (3280 feet (ft)) for impact driving. The enclosed 
nature of the area restricts the propagation of noise in most 
directions before noise levels reduce below the Level B harassment 
threshold for vibratory pile driving/DTH) Therefore, the area 
ensonified to the Level B harassment threshold is truncated by land in 
most directions. The ensonified area of the vibratory/drilling Level B 
harassment zone is 47km\2\ (18.15 mi\2\). Note that thresholds for 
behavioral disturbance are unweighted with respect to marine mammal 
hearing and therefore the thresholds apply to all species.

[[Page 42844]]

Marine Mammal Occurrence and Take Calculation and Estimation

    In this section we provide the information about the presence, 
density, or group dynamics of marine mammals that will inform the take 
calculations. We have density information for two species: Dall's 
porpoise and harbor porpoise. For the other five species we have 
information on presence, group size, and dive durations that we use to 
derive take estimates.
    In this section we then describe for each species how the marine 
mammal occurrence and/or density information is brought together to 
produce a quantitative take estimate. Level A harassment takes are 
requested for Dall's porpoise and harbor porpoise only as they are more 
cryptic and could enter a Level A harassment zone undetected. For the 
other species, the Level A harassment zones are small and shutdown 
measures can be implemented prior to any individual entering the Level 
A harassment zones. Take estimates for all stocks are shown in Table 5.
Humpback Whale
    Based on local information and Dahlheim et al. (2009) we estimate 
that up to eight individuals could be exposed to underwater noise each 
day. Our take estimate is then the product of the number of individuals 
per day times the 6 days of the project, or 48 Level B takes.
    For purposes of estimating effects and ESA takes of the Mexico DPS 
of humpback whales, we acknowledge that Mexico DPS whales cannot be 
readily distinguished from non-listed humpback whales in the project 
area. Based on Wade et al. (2016) we estimate that 3 of the 48 takes 
will be of the Mexico DPS.
    While individual humpback whales can generally be identified, due 
to the size of the monitoring zone it is possible this won't be the 
case in some instances. Further, it is possible that different monitors 
will sight the same whale, given the size of the monitoring zones and 
the distances humpback whales can move in a day. Thus it is 
conservatively assumed that there could be up to three interactions 
with each individual daily. PSOs may thus initially record more 
sightings than allowed takes until individuals being observed multiple 
time per day can be verified.
Steller Sea Lions
    As discussed above Steller sea lions are typically absent in the 
project area from mid-July through September. On the off chance that 
Steller sea lions will be present during construction for this project 
we used an average of the three sightings discussed above from 2005 and 
2013 to estimate the possible number of animals in the area. This 
average was 248 individuals. We assume that no more than 248 individual 
Steller sea lions will enter the action area on a given day of the 
project and calculate expected take as 248 times the 6 days of the 
project, or 1,488 takes. As discussed above, some of these takes will 
be eastern DPS Steller sea lions and some will be western DPS. We use 
the estimate from Hastings et al. (2020) that 1.4 percent of the 
animals in the project area are from the western DPS to allot 21 of the 
1,488 Level B takes to the western DPS and 1,467 of the takes to the 
eastern DPS.
Harbor Seal
    As discussed above, researchers estimate that they are 95 percent 
confident the population size of harbor seals in the area is not 
greater than 134 individuals. We use that estimate as the number of 
animals expected in the Level B harassment zone daily. Our take 
estimate is then the product of the number of individuals per day times 
the 6 days of the project, or 804 Level B takes.
    We know from Klinkhart et al. (2008) that animals dive and 
resurface every 4 minutes. That translates to potentially 15 sightings 
per hour. We also use the estimate that they spend 50 percent of their 
time hauled out. The project involved 36 hours of pile driving/drilling 
total. Individual sightings is estimated to be 134 seals times 7.5 in-
water sightings per hour times 36 hours of work, or 36,180 sightings. 
PSOs may thus initially record more sightings than allowed takes until 
individuals being observed multiple time per day can be verified.
Dall's Porpoise
    Density estimates were determined for Dall's porpoises for areas in 
Southeast Alaska, however densities specific to the Lynn Canal/Favorite 
Channel area are not available. However, surveys occurred closest to 
the project area in 1991, 1992, and 2007. These surveys found densities 
(porpoises/100km\2\) during summer months of 18.5, 14.3, and 17.8 
(Dahlheim et al., 2009). We used the average of these densities (16.9 
porpoises/100 km\2\) to calculate take. As noted above the ensonified 
area is 47 km\2\. Thus estimated take is 16.9/100 km\2\ times 47 km\2\ 
times 6 days, or 48 takes.
    Due to the size of the Level A harassment zone associated with 
drilling, and the cryptic nature of Dall's porpoises, it is possible 
Dall's porpoises may enter the Level A harassment zones undetected. It 
is conservatively assumed that up to four harbor porpoises (the mean 
group size from Dahlheim et al. 2009) may enter the Level A harassment 
once during the duration of the project. Thus we allot the 48 takes 
above to 4 Level A takes and 44 Level B takes.
Harbor Porpoise
    Density was estimated for harbor porpoises in Lynn Canal by 
Dahlhein et al. (2015) to be 0.2 individuals/km\2\. As noted above the 
ensonified area is 47 km\2\. Thus estimated take is 0.2/km\2\ times 47 
km\2\ times 6 days, or 57 takes.
    Due to the size of the Level A harassment zone associated with 
drilling, and the stealthy nature of harbor porpoises with no visible 
blow and a low profile, it is possible harbor porpoises may enter the 
Level A harassment zone undetected. Because they are most commonly 
observed in pairs (Dahlheim et al. 2009), it is conservatively assumed 
that one pair of harbor porpoises may enter the Level A harassment zone 
every other day of pile driving. Thus we allot the 57 takes above to 6 
Level A takes and 51 Level B takes.
Killer Whale
    Based on the information available as discussed above, it is 
conservatively estimated that 2 interactions with the average group 
size of residents (33) and 2 interactions with the average group size 
of transients (5) may be occur during the 6 days of the project. Thus 
we expect 76 Level B takes of killer whales.
Minke Whale
    There are no known occurrences of minke whales within the project 
area, however since their ranges extend into the project area and they 
have been observed in southeast Alaska (Dahlheim et al., 2009), it is 
possible minke whales could occur near the project. It is estimated up 
to one minke whale could be exposed to elevated noise levels from the 
project. Therefore, 1 Level B take is proposed to be authorized.

[[Page 42845]]



         Table 5--Proposed Authorized Level A and B Take and Percent of MMPA Stock Proposed To Be Taken
----------------------------------------------------------------------------------------------------------------
                                                                     Proposed authorized take
                             Species                             --------------------------------   % of Stock
                                                                      Level B         Level A
----------------------------------------------------------------------------------------------------------------
Humpback Whale \1\..............................................              48               0             1.4
Minke Whale.....................................................               1               0             N/A
Killer Whale....................................................              76               0             2.9
Harbor Porpoise.................................................              51               6             5.9
Dall's Porpoise.................................................              44               4             N/A
Harbor Seal.....................................................             804               0             8.5
Steller Sea Lion (Eastern DPS) \2\..............................            1467               0             3.5
Steller Sea Lion (Western DPS) \2\..............................              21               0            0.04
----------------------------------------------------------------------------------------------------------------
\1\ Distribution of proposed take by ESA status is 36 Level B takes for Hawaii DPS and 12 Level B take for
  Mexico DPS.
\2\ Total estimated take of Steller sea lions was 1488. Distribution between the stocks was calculated assuming
  1.4% Western DPS and rounding to nearest whole number.

Effects of Specified Activities on Subsistence Uses of Marine Mammals

    The availability of the affected marine mammal stocks or species 
for subsistence uses may be impacted by this activity. The subsistence 
uses that may be affected and the potential impacts of the activity on 
those uses are described below. The information from this section is 
analyzed to determine whether the necessary findings may be made in the 
Unmitigable Adverse Impact Analysis and Determination section.
    Subsistence harvest of harbor seals and Steller sea lions by Alaska 
Natives is not prohibited by the MMPA. No records exist of subsistence 
harvests of whales and porpoises in Lynn Canal (Haines, 2007). The 
Alaska Department of Fish and Game (ADF&G) has regularly conducted 
surveys of harbor seal and Steller sea lion subsistence harvest in 
Alaska and the number of Steller sea lions taken for subsistence in 
this immediate area from 1992-2008, and 2012 is only two (Wolfe et al. 
2013). Subsequent to the 2012 reporting year through 2017, an estimated 
one to three Steller sea lions have been taken annually outside Sitka 
Sound (personal communication with Lauren Sill, ADF&G, 83 FR 52394; 
October 17, 2018). Based upon data for harbor seal harvests, hunters in 
Southeast Alaska took from 523 to 719 harbor seals annually in the 
years 1992-2008. In 2012 an estimated 595 harbor seals were taken for 
subsistence uses (Wolfe et al. 2013). Seals were harvested across the 
year, with peak harvests in March, May, and October. Most recent 
reported data for the Juneau area indicates that in 2012, an estimated 
26 harbor seal were harvested for food (Wolfe et al. 2013). From 2013 
through 2019, Juneau area harbor seal hunting has continued, with 
several cultural heritage programs teaching students how to harvest, 
cut and store seal meat. However, there is no information on take 
numbers from 2013-2019 (personal communication with Lauren Sill, 
ADF&G).
    Since there is very little sea lion hunting in the Juneau area, 
short term displacement of animals from the project area is anticipated 
to have no effect on abundance or availability of Steller sea lions to 
subsistence hunters. Further, due to the project timing, Steller sea 
lions are typically absent from the project area and it is likely none 
will be displaced. The Douglas Indian Association, Sealaska Heritage 
Institute, and the Central Council of the Tlingit and Haida Indian 
Tribes of Alaska (Central Council) were contacted during December 2019 
to discuss this project. The Douglas Indian Association responded that 
they did not see any impacts that may affect their subsistence use. 
Chuck Smythe, with the Sealaska Heritage Institute, responded 
indicating that there is known harbor seal hunting in the project area. 
The other groups have not responded.
    Construction activities at the project site would be expected to 
cause only short term, non-lethal disturbance of marine mammals. 
Construction activities are localized and temporary, mitigation 
measures will be implemented to minimize disturbance of marine mammals 
in the action area, and, the project will not result in significant 
changes to availability of subsistence resources. Impacts on the 
abundance or availability of either species to subsistence hunters in 
the region are thus not anticipated.

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 grounds, and areas of similar significance, and on 
the availability of the species or stock for taking for certain 
subsistence uses. 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, as 
well as subsistence uses. 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.
    The following mitigation measures are in the IHA:
     Schedule: Pile driving or removal would occur during 
daylight hours. If poor environmental conditions restrict visibility 
(e.g., from excessive wind or

[[Page 42846]]

fog, high Beaufort state), pile installation would be delayed. No pile 
driving would occur from March 1 through May 31 to avoid peak marine 
mammal abundance periods and critical foraging periods;
     Pile Driving Delay/Shut-Down: For use of in-water heavy 
machinery/vessel (e.g., dredge), GCHS will implement a minimum shutdown 
zone of 10 m radius around the pile/vessel. For vessels, GCHS must 
cease operations and reduce vessel speed to the minimum required to 
maintain steerage and safe working conditions. In addition, if an 
animal comes within the shutdown zone (see Table 6) of a pile being 
driven or removed, GCHS would shut down. The shutdown zone would only 
be reopened when a marine mammal has not been observed within the 
shutdown zone for a 15 minutes have passed without subsequent 
detections of small cetaceans and pinnipeds; or 30 minutes have passed 
without subsequent detections of large cetaceans. If pile driving is 
stopped, pile installation would not commence if pile any marine 
mammals are observed anywhere within the Level A harassment zone. Pile 
driving activities would only be conducted during daylight hours when 
it is possible to visually monitor for marine mammals. If a species for 
which authorization has not been granted, or if a species for which 
authorization has been granted but the authorized takes are met, GCHS 
would delay or shut-down pile driving if the marine mammal approaches 
or is observed within the Level A and/or B harassment zones;
     Soft-start: For all impact pile driving, a ``soft start'' 
technique will be used at the beginning of each pile installation day, 
or if pile driving has ceased for more than 30 minutes, to allow any 
marine mammal that may be in the immediate area to leave before 
hammering at full energy. The soft start requires GCHS to provide an 
initial set of three strikes from the impact hammer at reduced energy, 
followed by a 30 second waiting period, then two subsequent 3-strike 
sets. If any marine mammal is sighted within the Level A shutdown zone 
prior to pile-driving, or during the soft start, GCHS will delay pile-
driving until the animal is confirmed to have moved outside and is on a 
path away from the Level A harassment zone or if 15 minutes have passed 
without subsequent detections of small cetaceans and pinnipeds; or 30 
minutes have passed without subsequent detections of large cetaceans; 
and
     Other best management practices: GCHS will drive all piles 
with a vibratory hammer to the maximum extent possible (i.e., until a 
desired depth is achieved or to refusal) prior to using an impact 
hammer and will use DTH drilling prior to using an impact hammer. GCHS 
will also use the minimum hammer energy needed to safely install the 
piles.
    Based on our evaluation of the applicant's proposed measures, NMFS 
has determined that the 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, and on the availability of 
such species or stock for subsistence uses.

                                                Table 6--Shutdown Zones for Each Activity Type and Stock
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                   Shutdown zone--permitted species                                   Level B harassment
                                 ----------------------------------------------------------------------------------------------------        zone
             Source                 Low- frequency      Mid- frequency      High- frequency                                          -------------------
                                       cetaceans           cetaceans           cetaceans            Phocids            Otariids           All species
--------------------------------------------------------------------------------------------------------------------------------------------------------
Vibratory.......................  80 m (265 ft).....  10 m (35 ft)......  120 m (395 ft)....  50 m (165 ft).....  10 m (35 ft)......  12.1 km (7.5
                                                                                                                                       miles).
DTH drilling....................  140 m (460 ft)....  10 m (35 ft)......  165 m (213 ft)....  75 m (246 ft).....  10 m (35 ft)......  12.1 km (7.5
                                                                                                                                       miles).
Impact Pile Driving.............  185 m (605 ft)....  10 m (35 ft)......  220 m (720 ft)....  100 m (325 ft)....  10 m (35 ft)......  1000 m (3280 ft).
--------------------------------------------------------------------------------------------------------------------------------------------------------

Monitoring and Reporting

    In order to issue an IHA for an activity, Section 101(a)(5)(D) of 
the MMPA states that NMFS must set forth requirements pertaining to the 
monitoring and reporting of such taking. The MMPA implementing 
regulations at 50 CFR 216.104 (a)(13) indicate that requests for 
authorizations must include the suggested means of accomplishing the 
necessary monitoring and reporting that will result in increased 
knowledge of the species and of the level of taking or impacts on 
populations of marine mammals that are expected to be present in the 
proposed action area. Effective reporting is critical both to 
compliance as well as ensuring that the most value is obtained from the 
required monitoring.
    Monitoring and reporting requirements prescribed by NMFS should 
contribute to improved understanding of one or more of the following:
     Occurrence of marine mammal species or stocks in the area 
in which take is anticipated (e.g., presence, abundance, distribution, 
density);
     Nature, scope, or context of likely marine mammal exposure 
to potential stressors/impacts (individual or cumulative, acute or 
chronic), through better understanding of: (1) Action or environment 
(e.g., source characterization, propagation, ambient noise); (2) 
affected species (e.g., life history, dive patterns); (3) co-occurrence 
of marine mammal species with the action; or (4) biological or 
behavioral context of exposure (e.g., age, calving or feeding areas);
     Individual marine mammal responses (behavioral or 
physiological) to acoustic stressors (acute, chronic, or cumulative), 
other stressors, or cumulative impacts from multiple stressors;
     How anticipated responses to stressors impact either: (1) 
Long-term fitness and survival of individual marine mammals; or (2) 
populations, species, or stocks;
     Effects on marine mammal habitat (e.g., marine mammal prey 
species, acoustic habitat, or other important physical components of 
marine mammal habitat); and
     Mitigation and monitoring effectiveness.

Visual Monitoring

    Monitoring would be conducted 30 minutes before, during, and 30 
minutes after pile driving activities. In addition, observers shall 
record all incidents of marine mammal occurrence, regardless of 
distance from activity, and shall document any behavioral reactions in

[[Page 42847]]

concert with distance from piles being driven or removed. Pile driving 
activities include the time to install a single pile or series of 
piles, as long as the time elapsed between uses of the pile driving 
equipment is no more than 30 minutes.
    A primary PSO would be placed at the project site where pile 
driving would occur. The primary purpose of this observer is to monitor 
and implement the Level A shutdown zones. Two additional observers 
would focus on monitoring large parts of the Level B harassment zone as 
well as visible parts of the Level A shutdown and harassment zones. The 
locations are shown in Figure 2 of the monitoring plan. Since not all 
of the Level B harassment zone will be observable by PSOs, they will 
calculate take for the project by extrapolating the observable area for 
each stock to the total size of the Level B harassment zone. PSOs would 
scan the waters using binoculars, and/or spotting scopes, and would use 
a handheld GPS or range-finder device to verify the distance to each 
sighting from the project site. All PSOs would be trained in marine 
mammal identification and behaviors and are required to have no other 
project-related tasks while conducting monitoring. The following 
measures also apply to visual monitoring:
    (1) Monitoring will be conducted by qualified observers, who will 
be placed at the best vantage point(s) practicable to monitor for 
marine mammals and implement shutdown/delay procedures when applicable 
by calling for the shutdown to the hammer operator. Qualified observers 
are trained biologists, with the following minimum qualifications;
    (a) Visual acuity in both eyes (correction is permissible) 
sufficient for discernment of moving targets at the water's surface 
with ability to estimate target size and distance; use of binoculars 
may be necessary to correctly identify the target;
    (b) Advanced education in biological science or related field 
(undergraduate degree or higher required);
    (c) Experience and ability to conduct field observations and 
collect data according to assigned protocols (this may include academic 
experience);
    (d) Experience or training in the field identification of marine 
mammals, including the identification of behaviors;
    (e) Sufficient training, orientation, or experience with the 
construction operation to provide for personal safety during 
observations;
    (f) Writing skills sufficient to prepare a report of observations 
including but not limited to the number and species of marine mammals 
observed; dates and times when in-water construction activities were 
conducted; dates and times when in-water construction activities were 
suspended to avoid potential incidental injury from construction sound 
of marine mammals observed within a defined shutdown zone; and marine 
mammal behavior; and
    (g) Ability to communicate orally, by radio or in person, with 
project personnel to provide real-time information on marine mammals 
observed in the area as necessary; and
    (2) GCHS shall submit observer Curriculum Vitaes for approval by 
NMFS.
    A draft marine mammal monitoring report would be submitted to NMFS 
within 90 days after the completion of pile driving activities, or 60 
days prior to a requested date of issuance of any future IHAs for 
projects at the same location, whichever comes first. It will include 
an overall description of work completed, a narrative regarding marine 
mammal sightings, and associated marine mammal observation data sheets. 
Specifically, the report must include:
     Dates and times (begin and end) of all marine mammal 
monitoring;
     Construction activities occurring during each daily 
observation period, including how many and what type of piles were 
driven or removed and by what method (i.e., impact or vibratory);
     Weather parameters and water conditions during each 
monitoring period (e.g., wind speed, percent cover, visibility, sea 
state);
     The number of marine mammals observed, by species, 
relative to the pile location and if pile driving or removal was 
occurring at time of sighting;
     Age and sex class, if possible, of all marine mammals 
observed;
     PSO locations during marine mammal monitoring;
     Distances and bearings of each marine mammal observed to 
the pile being driven or removed for each sighting (if pile driving or 
removal was occurring at time of sighting);
     Description of any marine mammal behavior patterns during 
obsevation, including direction of travel and estimated time spent 
within the Level A and Level B harassment zones while the source was 
active;
     Number of individuals of each species (differentiated by 
month as appropriate) detected within the monitoring zone, and 
estimates of number of marine mammals taken, by species (a correction 
factor may be applied to total take numbers, as appropriate;
     Detailed information about any implementation of any 
mitigation triggered (e.g., shutdowns and delays), a description of 
specific actions that ensued, and resulting behavior of the animal, if 
any;
     Description of attempts to distinguish between the number 
of individual animals taken and the number of incidences of take, such 
as ability to track groups or individuals;
     An extrapolation of the estimated takes by Level B 
harassment based on the number of observed exposures within the Level B 
harassment zone and the percentage of the Level B harassment zone that 
was not visible; and
     Submit all PSO datasheets and/or raw sighting data (in a 
separate file from the Final Report referenced immediately above).
    If no comments are received from NMFS within 30 days, the draft 
final report will constitute the final report. If comments are 
received, a final report addressing NMFS comments must be submitted 
within 30 days after receipt of comments.
    In the event that personnel involved in the construction activities 
discover an injured or dead marine mammal, the IHA-holder shall report 
the incident to the Office of Protected Resources (OPR) (301-427-8401), 
NMFS and to the Alaska Regional Stranding Coordinator as soon as 
feasible. If the death or injury was clearly caused by the specified 
activity, the IHA-holder must immediately cease the specified 
activities until NMFS is able to review the circumstances of the 
incident and determine what, if any, additional measures are 
appropriate to ensure compliance with the terms of the IHA. The IHA-
holder must not resume their activities until notified by NMFS. 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);
     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.

[[Page 42848]]

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, the discussion of our analyses applies to all 
the species listed in Table 5, given that the anticipated effects of 
this activity on these different marine mammal stocks are expected to 
be similar. There is little information about the nature or severity of 
the impacts, or the size, status, or structure of any of these species 
or stocks that would lead to a different analysis for this activity. 
Pile driving and drilling activities have the potential to disturb or 
displace marine mammals. Specifically, the project activities may 
result in take, in the form of Level A harassment and Level B 
harassment from underwater sounds generated from pile driving and DTH 
drilling. Potential takes could occur if individuals of these species 
are present in the ensonified zone when these activities are underway.
    The takes from Level A and Level B harassment would be due to 
potential behavioral disturbance, Temporary Threshold Shift (TTS), and 
PTS. No mortality is anticipated given the nature of the activity and 
measures designed to minimize the possibility of injury to marine 
mammals. Level A harassment is only authorized for Dall's porpoise and 
harbor porpoise. The potential for harassment is minimized through the 
construction method and the implementation of the planned mitigation 
measures (see Mitigation section).
    Behavioral responses of marine mammals to pile driving at the 
project site, if any, are expected to be mild and temporary. Marine 
mammals within the Level B harassment zone may not show any visual cues 
they are disturbed by activities (as noted during modification to the 
Kodiak Ferry Dock) or could become alert, avoid the area, leave the 
area, or display other mild responses that are not observable such as 
changes in vocalization patterns. Given the short duration of noise-
generating activities per day and that pile driving would occur on no 
more than 4 days, any harassment would be temporary. In addition, GCHS 
would not conduct pile driving during the spring eulachon and herring 
runs, when marine mammals are in greatest abundance and engaging in 
concentrated foraging behavior. There are no other areas or times of 
known biological importance for any of the affected species.
    In addition, although some affected humpback whales and Steller sea 
lions may be from a DPS that is listed under the ESA, it is unlikely 
that minor noise effects in a small, localized area of habitat would 
have any effect on the stocks' ability to recover. In combination, we 
believe that these factors, as well as the available body of evidence 
from other similar activities, demonstrate that the potential effects 
of the specified activities will have only minor, short-term effects on 
individuals. The specified activities are not expected to impact rates 
of recruitment or survival and will therefore not result in population-
level impacts.
    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;
     Authorized Level A harassment would be very small amounts 
and of low degree for two cryptic species;
     GCHS would avoid pile driving during peak periods of 
marine mammal abundance and foraging (i.e., March 1 through May 31 
eulachon and herring runs);
     GCHS would implement mitigation measures such as vibratory 
driving piles to the maximum extent practicable, soft-starts, and shut 
downs; and
     Monitoring reports from similar work in Alaska have 
documented little to no effect on individuals of the same species 
impacted by the specified activities.
    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 monitoring and mitigation 
measures, NMFS finds that the total marine mammal take from the 
proposed activity will have a negligible impact on all affected marine 
mammal species or stocks.

Small Numbers

    As noted above, only small numbers of incidental take may be 
authorized under Section 101(a)(5)(D) of the MMPA for specified 
activities other than military readiness activities. The MMPA does not 
define small numbers and so, in practice, where estimated numbers are 
available, NMFS compares the number of individuals taken to the most 
appropriate estimation of abundance of the relevant species or stock in 
our determination of whether an authorization is limited to small 
numbers of marine mammals. Additionally, other qualitative factors may 
be considered in the analysis, such as the temporal or spatial scale of 
the activities.
    The amount of take NMFS proposes to authorize is less than one-
third of any stock's best population estimate (and in fact, no more 
than 10 percent for any stock). These are all likely conservative 
estimates because we assume all takes are of different individual 
animals which is likely not the case, especially for harbor seals and 
Steller sea lions, which have the largest take. The Alaska stock of 
Dall's porpoise has no official NMFS abundance estimate as the most 
recent estimate is greater than eight years old. Nevertheless, the most 
recent estimate was 83,400 animals and it is highly unlikely this 
number has drastically declined. Therefore, the 48 authorized takes of 
this stock clearly represent small numbers of this stock. The Alaska 
stock of minke whale has no stock-wide abundance estimate. The stock 
ranges from the Bering and Chukchi seas south through the Gulf of 
Alaska. Surveys in portions of the range have estimated abundances of 
2,020 on the eastern Bering Sea shelf and 1,233 from the Kenai Fjords 
in the Gulf of Alaska to the central Aleutian Islands. Thus there 
appears to be thousands of

[[Page 42849]]

animals at least in the stock and clearly the 1 authorized takes of 
this stock represent small numbers of this stock.
    Based on the analysis contained herein of the proposed activity 
(including the mitigation and monitoring measures) and the anticipated 
take of marine mammals, NMFS finds that small numbers of marine mammals 
will be taken relative to the population size of the affected species 
or stocks.

Unmitigable Adverse Impact Analysis and Determination

    In order to issue an IHA, NMFS must find that the specified 
activity will not have an ``unmitigable adverse impact'' on the 
subsistence uses of the affected marine mammal species or stocks by 
Alaskan Natives. NMFS has defined ``unmitigable adverse impact'' in 50 
CFR 216.103 as an impact resulting from the specified activity: (1) 
That is likely to reduce the availability of the species to a level 
insufficient for a harvest to meet subsistence needs by: (i) Causing 
the marine mammals to abandon or avoid hunting areas; (ii) Directly 
displacing subsistence users; or (iii) Placing physical barriers 
between the marine mammals and the subsistence hunters; and (2) That 
cannot be sufficiently mitigated by other measures to increase the 
availability of marine mammals to allow subsistence needs to be met.
    As discussed above in the subsistence uses section, subsistence 
harvest of harbor seals and other marine mammals is rare in the area 
and local subsistence users have not expressed concern about this 
project. All project activities will take place within the Favorite 
Channel area where subsistence activities do not generally occur. The 
project also will not have an adverse impact on the availability of 
marine mammals for subsistence use at locations farther away, where 
these construction activities are not expected to take place. Some 
minor, short-term harassment of the harbor seals and Steller sea lions 
could occur, but any effects on subsistence harvest activities in the 
region will be minimal, and not have an adverse impact.
    Based on the effects and location of the specified activity, and 
the mitigation and monitoring measures, NMFS has determined that there 
will not be an unmitigable adverse impact on subsistence uses from 
GCHS's planned activities.

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 (IHAs with no anticipated serious injury or 
mortality) of the Companion Manual for NOAA Administrative Order 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 issuance of the proposed IHA qualifies to be categorically 
excluded from further NEPA review.

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, in this case with the Alaska Region Protected 
Resources Division Office, whenever we propose to authorize take for 
endangered or threatened species.
    NMFS is proposing to authorize take of Western DPS Steller sea lion 
(Eumetopias jubatus) and Mexico DPS of humpback whales (Megaptera 
novaeangliae), which are listed under the ESA. The NMFS Alaska Regional 
Office Protected Resources Division issued a Biological Opinion on June 
25, 2020 under section 7 of the ESA, on the issuance of an IHA to GCHS 
under section 101(a)(5)(D) of the MMPA by the NMFS Permits and 
Conservation Division. The Biological Opinion concluded that the 
proposed action is not likely to jeopardize the continued existence of 
the above species, and is not likely to destroy or adversely modify 
western DPS Steller sea lion critical habitat.

Authorization

    NMFS has issued an IHA to GCHS for the potential harassment of 
small numbers of seven marine mammal species incidental to conducting 
the Sentinel Island Moorage Float project near Juneau, Alaska between 
July 15, 2020 and September 20, 2020, provided the previously mentioned 
mitigation, monitoring, and reporting requirements are incorporated.

    Dated: July 9, 2020.
Donna S. Wieting,
Director, Office of Protected Resources, National Marine Fisheries 
Service.
[FR Doc. 2020-15198 Filed 7-14-20; 8:45 am]
BILLING CODE 3510-22-P