Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to Gastineau Channel Historical Society Sentinel Island Moorage Float Project, Juneau, Alaska, 18196-18213 [2020-06787]

Agencies

• DEPARTMENT OF COMMERCE
• National Oceanic and Atmospheric Administration

[Federal Register Volume 85, Number 63 (Wednesday, April 1, 2020)]
[Notices]
[Pages 18196-18213]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2020-06787]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

[RTID 0648-XR097]


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

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SUMMARY: NMFS has received a request from Gastineau Channel Historical 
Society (GCHS) for authorization to take marine mammals incidental to 
Sentinel Island Moorage Float project near Juneau, Alaska. Pursuant to 
the Marine Mammal Protection Act (MMPA), NMFS is requesting comments on 
its proposal to issue an incidental harassment authorization (IHA) to 
incidentally take marine mammals during the specified activities. NMFS 
is also requesting comments on a possible one-year renewal that could 
be issued under certain circumstances and if all requirements are met, 
as described in Request for Public Comments at the end of this notice. 
NMFS will consider public comments prior to making any final decision 
on the issuance of the requested MMPA authorizations and agency 
responses will be summarized in the final notice of our decision.

DATES: Comments and information must be received no later than May 1, 
2020.

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

FOR FURTHER INFORMATION CONTACT: 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.
    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.

[[Page 18197]]

    The definitions of all applicable MMPA statutory terms cited above 
are included in the relevant sections below.

National Environmental Policy Act

    To comply with the National Environmental Policy Act of 1969 (NEPA; 
42 U.S.C. 4321 et seq.) and NOAA Administrative Order (NAO) 216-6A, 
NMFS must review our proposed action (i.e., the issuance of an 
incidental harassment authorization) with respect to potential impacts 
on the human environment.
    This action is consistent with categories of activities identified 
in Categorical Exclusion B4 (incidental harassment authorizations 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 preliminarily determined that the 
issuance of the proposed IHA qualifies to be categorically excluded 
from further NEPA review.
    We will review all comments submitted in response to this notice 
prior to concluding our NEPA process or making a final decision on the 
IHA request.

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 Proposed 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.
    The pile driving or DTH drilling can result in take of marine 
mammals from sound in the water which results in behavioral harassment 
(Level B harassment) or auditory injury (Level A harassment). The 
footprint of the project is approximately one square mile around the 
project site. The project will take no more than 6 days of pile-
driving/DTH drilling.

Dates and Duration

    The work for which take will be authorized will occur between July 
15, 2020 and September 20, 2020. Noise generating activities will not 
overlap with high densities of marine mammal prey that occur March 1 
through May 31. The daily construction window for pile driving would 
begin no sooner than 30 minutes after sunrise and would end 30 minutes 
prior to sunset to allow for marine mammal monitoring.

Specific Geographic Region

    The project site is located at Sentinel Island at the northern end 
of Favorite Channel at its convergence with Lynn Canal near Juneau, 
Alaska (Figure 1). In 2004 the Sentinel Island Lighthouse was 
transferred to the Gastineau Channel Historical Society from the U.S. 
Coast Guard. The proposed mooring float is adjacent to the lighthouse 
on the island. In a similar location to the proposed float there was an 
old timber dock with a hoist house that was demolished in 2004.
BILLING CODE 3510-22-P

[[Page 18198]]

[GRAPHIC] [TIFF OMITTED] TN01AP20.000

BILLING CODE 3510-22-C
    Several seasonally available prey species are abundant within the 
project area. Herring (Clupea pallasii) are abundant in dense 
aggregations in the spring and fall, coinciding with when Steller sea 
lion numbers peak at Benjamin Island to the north (Womble 2003). In 
Southeast Alaska, spawning of eulachon (Thaleichtys pacificus) and 
capelin (Mallotus villosus) also occurs in the spring (Womble et al. 
2009).
    The underwater acoustic environment in the project area is 
dominated by ambient noise from day-to-day vessel activities.

Detailed Description of Specific Activity

    The 16 by 60 foot float and 8 by 88 foot gangway will be fabricated 
and moved to the installation site. To support these structures, six 
24-inch diameter steel pipes would be driven into the substrate at the 
project location. The pipe piles would be installed to a depth of at 
least 15 feet or more below the surface using a crane-mounted vibratory 
and/or impact hammer located on a barge. It may take up to about 60 
minutes per pile of vibratory driving to set each pile. If impact 
hammering is used, about 250 strikes would be needed to drive each of 
the piles to a sufficient depth which may require about 15 minutes of 
hammering. Installation will begin with use of the vibratory hammer, 
then drilling will begin at the bedrock interface and at the end the 
final setting of the pile in the drilled socket will be done with the 
vibratory hammer. DTH drilling will be used to install the rock 
sockets. It is estimated that about 6 hours (maximum) would be required 
to drive each pile and they would be proofed the same day.
    Multiple piles would not be concurrently driven. Under the best-
case scenario, using solely vibratory and DTH drilling, two piles would 
be set in

[[Page 18199]]

a day. Therefore, the duration of drilling activity for the four piles 
could be as short as 3 days or as long as 6 days. Thus in the worst 
case, the entire project would take a total of 6 days of pile driving/
drilling.
    Proposed mitigation, monitoring, and reporting measures are 
described in detail later in this document (please see Proposed 
Mitigation and Proposed Monitoring and Reporting).
Description of Marine Mammals in the Area of Specified Activities
    Sections 3 and 4 of the 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,
                                                                                       ESA/MMPA  status;       Nmin, most recent               Annual  M/
            Common name                 Scientific name             Stock             Strategic (Y/N) \1\    abundance survey) \2\     PBR       SI \3\
 
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                                          Order Cetartiodactyla--Cetacea--Superfamily Mysticeti (baleen whales)
--------------------------------------------------------------------------------------------------------------------------------------------------------
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
Minke whale \4\....................  Balaenoptera           Alaska...............  -; N                      N/A, see text........        N/A          0
                                      acutorostrata.
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                            Superfamily Odontoceti (toothed whales, dolphins, and porpoises)
--------------------------------------------------------------------------------------------------------------------------------------------------------
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).
--------------------------------------------------------------------------------------------------------------------------------------------------------
\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-assessments 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 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.

[[Page 18200]]

 
\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.
    In addition, the northern sea otter may be found in the project 
vicinity. However, that species is managed by the U.S. Fish and 
Wildlife Service and is not considered further in this document.

Humpback Whale

    Humpback whales (Megaptera novaeangliae) in the North Pacific 
migrate from low-latitude breeding and calving grounds to form 
geographically distinct aggregations on higher-latitude feeding 
grounds. They occur in Lynn Canal where they feed on aggregations of 
herring in lower Lynn Canal.
    In 2016 NMFS revised the ESA listing of humpback whales (81 FR 
62259; September 8, 2016). NMFS is in the process of reviewing humpback 
whale stock structure and abundance under the MMPA in light of the ESA 
revisions. The MMPA stock in Alaska is considered to be the Central 
North Pacific stock. Humpbacks from 2 of the 14 newly identified 
Distinct Population Segments (DPSs) occur in the project area: The 
Mexico DPS, which is a threatened species; and the Hawaii DPS, which is 
not protected under the ESA. NMFS considers humpback whales in 
Southeast Alaska to be 94 percent comprised of the Hawaii DPS and 6 
percent of the Mexico DPS (Wade et al., 2016). While the range of the 
Mexico DPS extends up to Southeast Alaska, this DPS has never been 
reported as far north as Sitka. The likelihood that an individual from 
the Mexico DPS is part of the relatively few humpback whales that move 
to Lynn Canal is extremely low; nevertheless, we use the 6 percent 
estimate to be conservative in this analysis.
    On October 9, 2019, NMFS published a proposed rule to designate 
critical habitat for the humpback whale (84 FR 54354). Areas proposed 
as critical habitat include specific marine areas off the coasts of 
California, Oregon, Washington and Alaska, including near the project 
area. GCHS expects to complete this project before the critical habitat 
designation is effective, therefore we do not consider it further in 
this analysis.
    Estimates of humpback whale abundance for the Mexico DPS are from 
the ESA listing process. Some whale researchers, resource managers, and 
whale watching guides track the presence of individual humpback whales 
in the Juneau area by unique fluke patterns (Teerlink, 2017). Based on 
fluke pattern identification from fluke photographs taken between 2006 
and 2014, 179 individual humpback whales were identified from the 
Juneau area (Teerlink, 2017). For Lynn Canal/Favorite Channel and other 
waters in the project vicinity including Stephens Passage, and Saginaw 
Channel, researchers have documented 4 to 18 humpback whales in winter 
(Krieger and Wing, 1986; Moran et al., 2018). Straley et al. (2011) 
surveyed humpback whales in Lynn Canal from September 15-October 14 in 
2007/2008 and during the same months in 2000/2009. During both years a 
total of 55 whale sighting (average of approximately 2 whales per day) 
were recorded, however in 2007/2008 there were 30 unique whales 
identified and in 2008/2009 there were 22 unique whales identified in 
the project vicinity.
    Dahlheim et al. (2009) found significant difference in the mean 
group size of humpback whales from year to year and also found that the 
average group size was largest in the fall (September/October), however 
no surveys were conducted in August. Information from the fall surveys 
is thus utilized, and is conservative because humpback numbers were 
found to peak during the fall in Lynn Canal (Straley et al., 2011).

Minke Whale

    There are three stocks of minke whales (Balaenopera acutorostrata) 
recognized in U.S. waters of the Pacific Ocean; only members of the 
Alaska stock could potentially occur within the project area. This 
stock has seasonal movements associated with feeding areas that are 
generally located at the edge of the pack ice (Muto et al., 2019). 
Minke whales are considered to be rare in Lynn Canal (Dahlheim et al., 
2009). However, minke whales forage on schooling fish and may rarely 
enter the project area. In 2015, one minke whale was sighted in Taiya 
Inlet, northeast of the Project Area (K. Gross, personal communication, 
as cited in 84 FR 4777, February 19, 2019).
    No comprehensive estimates of abundance have been made for the 
Alaska stock or near the project area, but a 2010 survey conducted on 
the eastern Bering Sea shelf produced a provisional abundance estimate 
of 2,020 whales (Friday et al., 2013).

Killer Whale

    NMFS recognizes eight killer whale (Orcinus orca) stocks throughout 
the Pacific Ocean. However, only three of these stocks can be found in 
Southeast Alaska: (1) the Alaska Resident stock ranges from 
southeastern Alaska to the Aleutian Islands and Bering Sea; (2) the 
Northern Resident stock occurs from Washington State through part of 
southeastern Alaska; and (3) the West Coast Transient stock ranges from 
California through southeastern Alaska (Muto et al., 2019). Resident 
and transient killer whales are sporadically and seasonally attracted 
to Lutak Inlet during the spring to feed on the large aggregations of 
fishes and pinnipeds.
    Killer whale abundance estimates are determined by a direct count 
of individually identifiable animals. Killer whales are observed within 
the project area several times annually. Data compiled by Oceanus 
Alaska found an average of 25 killer whales in the Statter Harbor area 
of Auke Bay each year. While killer whales occurring in Lynn Canal can 
belong to one of three stocks, photoidentification studies since 1970 
have catalogued most individuals observed in this area as belonging to 
the Northern Resident stock. The AG resident pod is one pod known to 
frequent the Juneau area (Dahlheim et al., 2009; B. Lambert personal 
observation) and has 41 members. This pod is seen in the area 
intermittently in groups of up to approximately 25 individuals (B. 
Lambert personal observation). The occurrence of transient killer 
whales in Lynn Canal increases in summer, with lower numbers observed 
in spring and fall. Dahlheim et al. (2009) found the average group size 
of resident orcas to be approximately 33 individuals during the summer 
(June/July) and 20 during the fall (September/October).

Dall's Porpoise

    Dall's porpoise (Phocoenoides dalli) are widely distributed 
throughout the region and have been observed in Lynn Canal (Dahlheim et 
al., 2009). They were observed more frequently in the spring, tapering 
off in summer and fall

[[Page 18201]]

in southeast Alaska (Jefferson et al., 2019). The Alaska stock is the 
only Dall's porpoise stock found in Alaska waters. Group sizes were 
generally small, under 5 individuals, and during the summer months the 
mean group size was 2.6.

Harbor Porpoise

    Harbor porpoise (Phocoena phocoena) are common in coastal waters of 
Alaska. There are three harbor porpoise stocks in Alaska, but only the 
Southeast Alaska stock occurs in the project area (Muto et al., 2019). 
Individuals from the Southeast Alaska stock of harbor porpoise are 
infrequently observed in Lynn Canal, though they have been observed as 
far north as Haines during the summer months (Dahlheim et al., 2015).

Steller Sea Lion

    Steller sea lions (Eumetopias jubatus) range along the North 
Pacific Rim from northern Japan to California, with centers of 
abundance and distribution in the Gulf of Alaska and Aleutian Islands. 
Large numbers of individuals widely disperse when not breeding (late 
May to early July) to access seasonally important prey resources (Muto 
et al., 2019). In 1997 NMFS identified two DPSs of Steller sea lions 
under the ESA: a Western DPS and an Eastern DPS (62 FR 24345, May 5, 
1997). The Eastern DPS is not ESA-listed, the Western DPS is. For MMPA 
purposes the Eastern DPS is called the Eastern U.S. stock and the 
Western DPS is called the Western U.S. stock. For simplicity we will 
refer to them by their DPS name in this analysis. Most of the Steller 
sea lions in southeastern Alaska have been determined to be part of the 
Eastern DPS, however, in recent years there has been an increasing 
trend of the Western DPS animals occurring and breeding in southeastern 
Alaska (Muto et al., 2019).
    Steller sea lions have been observed in the project vicinity 
throughout the year. Salmon increase in importance as prey for sea 
lions from late-October and December. The closest haulout to the 
project area is Benjamin Island, about 1 mile northeast. Typically the 
sea lions vacate Benjamin Island mid-July through late-September, 
however some years individuals have remained. In surveys conducted from 
2004 to 2018, Steller sea lions were absent from July 17 through 
September 28 at Benjamin Island with the exception of 2005 and 2013. On 
July 16, 2005 560 non-pups were observed; on August 9, 2013, 40 non-
pups were counted; and on September 24, 2013, 144 non-pups were 
observed (Jemison, Alaska Fish and Game, personal communication).
    Individuals from the Western DPS have been observed in the Lynn 
Canal area. The percentage of Western DPS animals estimated to occur in 
the project area in the summer is estimated to be 1.4 percent (Hastings 
et al., in press); for the rest of this analysis we assume that 1.4 
percent of the Steller sea lions in the project area are from the 
Western DPS.

Harbor Seal

    Harbor seals (Phoca vitulina) inhabit coastal and estuarine waters 
off Alaska. They haul out on rocks, reefs, beaches, and drifting 
glacial ice. Up to 44 percent of their time is spent hauled out, with 
hauling out occurring more often during the summer (Pitcher and 
Calkins, 1979; Klinkhart et al., 2008). They are opportunistic feeders 
and often adjust their distribution to take advantage of locally and 
seasonally abundant prey (Womble et al., 2009; Allen and Angliss, 
2015). Harbor seals occurring in the project area belong to the Lynn 
Canal/Stephens Passage (LC/SP) stock. NOAA 2018 abundance estimates for 
the unit in which the action area is located is 42.06 harbor seals at a 
haulout on the east coast of Sentinel Island with the 95 percent 
confidence interval for that estimate at 134 seals.

Marine Mammal Hearing

    Hearing is the most important sensory modality for marine mammals 
underwater, and exposure to anthropogenic sound can have deleterious 
effects. To appropriately assess the potential effects of exposure to 
sound, it is necessary to understand the frequency ranges marine 
mammals are able to hear. Current data indicate that not all marine 
mammal species have equal hearing capabilities (e.g., Richardson et 
al., 1995; Wartzok and Ketten, 1999; Au and Hastings, 2008). To reflect 
this, Southall et al. (2007) recommended that marine mammals be divided 
into functional hearing groups based on directly measured or estimated 
hearing ranges on the basis of available behavioral response data, 
audiograms derived using auditory evoked potential techniques, 
anatomical modeling, and other data. Note that no direct measurements 
of hearing ability have been successfully completed for mysticetes 
(i.e., low-frequency cetaceans). Subsequently, NMFS (2018) described 
generalized hearing ranges for these marine mammal hearing groups. 
Generalized hearing ranges were chosen based on the approximately 65 
decibel (dB) threshold from the normalized composite audiograms, with 
the exception for lower limits for low-frequency cetaceans where the 
lower bound was deemed to be biologically implausible and the lower 
bound from Southall et al. (2007) retained. Marine mammal hearing 
groups and their associated hearing ranges are provided in Table 2.

                               Table 2--Marine Mammal Hearing Groups (NMFS, 2018)
----------------------------------------------------------------------------------------------------------------
                     Hearing group                                     Generalized hearing  range *
----------------------------------------------------------------------------------------------------------------
Low-frequency (LF) cetaceans (baleen whales)...........  7 Hz to 35 kHz
Mid-frequency (MF) cetaceans (dolphins, toothed whales,  150 Hz to 160 kHz
 beaked whales, bottlenose whales).
High-frequency (HF) cetaceans (true porpoises, Kogia,    275 Hz to 160 kHz
 river dolphins, cephalorhynchid, Lagenorhynchus
 cruciger & L. australis).
Phocid pinnipeds (PW) (underwater) (true seals)........  50 Hz to 86 kHz
Otariid pinnipeds (OW) (underwater) (sea lions and fur   60 Hz to 39 kHz
 seals).
----------------------------------------------------------------------------------------------------------------
\*\ Represents the generalized hearing range for the entire group as a composite (i.e., all species within the
  group), where individual species' hearing ranges are typically not as broad. Generalized hearing range chosen
  based on ~65 dB threshold from normalized composite audiogram, with the exception for lower limits for LF
  cetaceans (Southall et al. 2007) and PW pinniped (approximation).

    The pinniped functional hearing group was modified from Southall et 
al. (2007) on the basis of data indicating that phocid species have 
consistently demonstrated an extended frequency range of hearing 
compared to otariids, especially in the higher frequency range 
(Hemil[auml] et al., 2006; Kastelein et al., 2009; Reichmuth and Holt, 
2013).
    For more detail concerning these groups and associated frequency 
ranges,

[[Page 18202]]

please see NMFS (2018) for a review of available information. Seven 
marine mammal species (five cetacean and two pinniped (one otariid and 
one phocid) species have the reasonable potential to co-occur with the 
proposed survey activities (see Table 1). Of the cetacean species that 
may be present, two are classified as low-frequency cetaceans (i.e., 
all mysticete species), one is classified as a mid-frequency cetacean 
(i.e., all delphinid and ziphiid species and the sperm whale), and two 
are classified as high-frequency cetaceans (i.e., harbor porpoise and 
Dall's porpoise).
Potential Effects of Specified Activities on Marine Mammals and Their 
Habitat
    This section includes a summary and discussion of the ways that 
components of the specified activity may impact marine mammals and 
their habitat. The Estimated Take section later in this document 
includes a quantitative analysis of the number of individuals that are 
expected to be taken by this activity. The Negligible Impact Analysis 
and Determination section considers the content of this section, the 
Estimated Take section, and the Proposed Mitigation section, to draw 
conclusions regarding the likely impacts of these activities on the 
reproductive success or survivorship of individuals and how those 
impacts on individuals are likely to impact marine mammal species or 
stocks.

Description of Sound Sources

    The marine soundscape is comprised of both ambient and 
anthropogenic sounds. Ambient sound is defined as the all-encompassing 
sound in a given place and is usually a composite of sound from many 
sources both near and far (ANSI 1994, 1995). The sound level of an area 
is defined by the total acoustical energy being generated by known and 
unknown sources. These sources may include physical (e.g., waves, wind, 
precipitation, earthquakes, ice, atmospheric sound), biological (e.g., 
sounds produced by marine mammals, fish, and invertebrates), and 
anthropogenic sound (e.g., vessels, dredging, aircraft, construction).
    The sum of the various natural and anthropogenic sound sources at 
any given location and time--which comprise ``ambient'' or 
``background'' sound--depends not only on the source levels (as 
determined by current weather conditions and levels of biological and 
shipping activity) but also on the ability of sound to propagate 
through the environment. In turn, sound propagation is dependent on the 
spatially and temporally varying properties of the water column and sea 
floor, and is frequency-dependent. As a result of the dependence on a 
large number of varying factors, ambient sound levels can be expected 
to vary widely over both coarse and fine spatial and temporal scales. 
Sound levels at a given frequency and location can vary by 10-20 dB 
from day to day (Richardson et al., 1995). The result is that, 
depending on the source type and its intensity, sound from the 
specified activity may be a negligible addition to the local 
environment or could form a distinctive signal that may affect marine 
mammals.
    In-water construction activities associated with the project would 
include impact pile driving, vibratory pile driving, and DTH drilling. 
The sounds produced by these activities fall into one of two general 
sound types: Impulsive and non-impulsive. Impulsive sounds (e.g., 
explosions, gunshots, sonic booms, impact pile driving) are typically 
transient, brief (less than 1 second), broadband, and consist of high 
peak sound pressure with rapid rise time and rapid decay (ANSI, 1986; 
NIOSH, 1998; ANSI, 2005; NMFS, 2018). Non-impulsive sounds (e.g., 
machinery operations such as drilling or dredging, vibratory pile 
driving, and active sonar systems) can be broadband, narrowband or 
tonal, brief or prolonged (continuous or intermittent), and typically 
do not have the high peak sound pressure with raid rise/decay time that 
impulsive sounds do (ANSI 1995; NIOSH 1998; NMFS 2018). The distinction 
between these two sound types is important because they have differing 
potential to cause physical effects, particularly with regard to 
hearing (e.g., Ward 1997 in Southall et al., 2007).
    Two types of pile hammers would be used on this project: Impact and 
vibratory. Impact hammers operate by repeatedly dropping a heavy piston 
onto a pile to drive the pile into the substrate. Sound generated by 
impact hammers is characterized by rapid rise times and high peak 
levels, a potentially injurious combination (Hastings and Popper, 
2005). Vibratory hammers install piles by vibrating them and allowing 
the weight of the hammer to push them into the sediment. Vibratory 
hammers produce significantly less sound than impact hammers. Peak 
Sound pressure Levels (SPLs) may be 180 dB or greater, but are 
generally 10 to 20 dB lower than SPLs generated during impact pile 
driving of the same-sized pile (Oestman et al., 2009). Rise time is 
slower, reducing the probability and severity of injury, and sound 
energy is distributed over a greater amount of time (Nedwell and 
Edwards, 2002; Carlson et al., 2005).
    DTH drilling would be conducted using a down-the-hole drill 
inserted through the hollow steel piles. A DTH drill is a drill bit 
that drills through the bedrock using a pulse mechanism that functions 
at the bottom of the hole. This pulsing bit breaks up rock to allow 
removal of debris and insertion of the pile. The head extends so that 
the drilling takes place just below the pile. The pulsing sounds 
produced by the DTH drilling method occur in a range of frequencies 
that depends on the size and type of the bit and the hammering pressure 
applied. Smaller diameter DTH drilling produces sounds that are 
generally continuous while larger and ring-type DTH drills produce 
sounds that can be a combination of continuous and impulsive. The DTH 
hammering for this project falls in the continuous range. In addition, 
this method likely increases sound attenuation because the noise is 
primarily contained within the steel pile and below ground as opposed 
to impact hammer driving methods which occur at the top of the pile and 
introduce sound into the water column to a greater degree. See also our 
detailed discussion of this sound source in the notice of issuance of 
an IHA for Ferry Berth Improvements in Tongass Narrows, Alaska https://www.govinfo.gov/content/pkg/FR-2020-01-07/pdf/2020-00038.pdf.
    The likely or possible impacts of GCHS's proposed activity on 
marine mammals could involve both non-acoustic and acoustic stressors. 
Potential non-acoustic stressors could result from the physical 
presence of the equipment and personnel; however, any impacts to marine 
mammals are expected to primarily be acoustic in nature. Acoustic 
stressors include effects of heavy equipment operation during pile 
installation and drilling.

Acoustic Impacts

    The introduction of anthropogenic noise into the aquatic 
environment from pile driving and DTH drilling is the primary means by 
which marine mammals may be harassed from GCHS's specified activity. In 
general, animals exposed to natural or anthropogenic sound may 
experience physical and psychological effects, ranging in magnitude 
from none to severe (Southall et al., 2007). Generally, exposure to 
pile driving and drilling noise has the potential to result in auditory 
threshold shifts and behavioral reactions (e.g., avoidance, temporary 
cessation of foraging and vocalizing, changes in dive behavior). 
Exposure to anthropogenic noise can also lead to

[[Page 18203]]

non-observable physiological responses such an increase in stress 
hormones. Additional noise in a marine mammal's habitat can mask 
acoustic cues used by marine mammals to carry out daily functions such 
as communication and predator and prey detection. The effects of pile 
driving and drilling noise on marine mammals are dependent on several 
factors, including, but not limited to, sound type (e.g., impulsive vs. 
non-impulsive), the species, age and sex class (e.g., adult male vs. 
mom with calf), duration of exposure, the distance between the pile and 
the animal, received levels, behavior at time of exposure, and previous 
history with exposure (Wartzok et al., 2003; Southall et al., 2007). 
Here we discuss physical auditory effects (threshold shifts) followed 
by behavioral effects and potential impacts on habitat.
    NMFS defines a noise-induced threshold shift (TS) as a change, 
usually an increase, in the threshold of audibility at a specified 
frequency or portion of an individual's hearing range above a 
previously established reference level (NMFS, 2018). The amount of 
threshold shift is customarily expressed in dB. A TS can be permanent 
or temporary. As described in NMFS (2018), there are numerous factors 
to consider when examining the consequence of TS, including, but not 
limited to, the signal temporal pattern (e.g., impulsive or non-
impulsive), likelihood an individual would be exposed for a long enough 
duration or to a high enough level to induce a TS, the magnitude of the 
TS, time to recovery (seconds to minutes or hours to days), the 
frequency range of the exposure (i.e., spectral content), the hearing 
and vocalization frequency range of the exposed species relative to the 
signal's frequency spectrum (i.e., how animal uses sound within the 
frequency band of the signal; e.g., Kastelein et al., 2014), and the 
overlap between the animal and the source (e.g., spatial, temporal, and 
spectral).
    Permanent Threshold Shift (PTS)--NMFS defines PTS as a permanent, 
irreversible increase in the threshold of audibility at a specified 
frequency or portion of an individual's hearing range above a 
previously established reference level (NMFS 2018). Available data from 
humans and other terrestrial mammals indicate that a 40 dB threshold 
shift approximates PTS onset (see Ward et al., 1958, 1959; Ward, 1960; 
Kryter et al., 1966; Miller, 1974; Ahroon et al., 1996; Henderson and 
Hu, 2008). PTS levels for marine mammals are estimates, with the 
exception of a single study unintentionally inducing PTS in a harbor 
seal (Kastak et al., 2008), there are no empirical data measuring PTS 
in marine mammals, largely due to the fact that, for various ethical 
reasons, experiments involving anthropogenic noise exposure at levels 
inducing PTS are not typically pursued or authorized (NMFS, 2018).
    Temporary Threshold Shift (TTS)--A temporary, reversible increase 
in the threshold of audibility at a specified frequency or portion of 
an individual's hearing range above a previously established reference 
level (NMFS, 2018). Based on data from cetacean TTS measurements (see 
Southall et al., 2007), a TTS of 6 dB is considered the minimum 
threshold shift clearly larger than any day-to-day or session-to-
session variation in a subject's normal hearing ability (Schlundt et 
al., 2000; Finneran et al., 2000, 2002). As described in Finneran 
(2016), marine mammal studies have shown the amount of TTS increases 
with cumulative sound exposure level (SELcum) in an 
accelerating fashion: At low exposures with lower SELcum, 
the amount of TTS is typically small and the growth curves have shallow 
slopes. At exposures with higher SELcum, the growth curves 
become steeper and approach linear relationships with the noise SEL.
    Depending on the degree (elevation of threshold in dB), duration 
(i.e., recovery time), and frequency range of TTS, and the context in 
which it is experienced, TTS can have effects on marine mammals ranging 
from discountable to serious (similar to those discussed in auditory 
masking, below). For example, a marine mammal may be able to readily 
compensate for a brief, relatively small amount of TTS in a non-
critical frequency range that takes place during a time when the animal 
is traveling through the open ocean, where ambient noise is lower and 
there are not as many competing sounds present. Alternatively, a larger 
amount and longer duration of TTS sustained during time when 
communication is critical for successful mother/calf interactions could 
have more serious impacts. We note that reduced hearing sensitivity as 
a simple function of aging has been observed in marine mammals, as well 
as humans and other taxa (Southall et al., 2007), so we can infer that 
strategies exist for coping with this condition to some degree, though 
likely not without cost.
    Currently, TTS data only exist for four species of cetaceans 
(bottlenose dolphin (Tursiops truncatus), beluga whale (Delphinapterus 
leucas), harbor porpoise, and Yangtze finless porpoise (Neophocoena 
asiaeorientalis)) and five species of pinnipeds exposed to a limited 
number of sound sources (i.e., mostly tones and octave-band noise) in 
laboratory settings (Finneran, 2015). TTS was not observed in trained 
spotted (Phoca largha) and ringed (Pusa hispida) seals exposed to 
impulsive noise at levels matching previous predictions of TTS onset 
(Reichmuth et al., 2016). In general, harbor seals and harbor porpoises 
have a lower TTS onset than other measured pinniped or cetacean species 
(Finneran, 2015). The potential for TTS from impact pile driving 
exists. After exposure to playbacks of impact pile driving sounds (rate 
2760 strikes/hour) in captivity, mean TTS increased from 0 dB after 15 
minute exposure to 5 dB after 360 minute exposure; recovery occurred 
within 60 minutes (Kastelein et al., 2016). Additionally, the existing 
marine mammal TTS data come from a limited number of individuals within 
these species. No data are available on noise-induced hearing loss for 
mysticetes. For summaries of data on TTS in marine mammals or for 
further discussion of TTS onset thresholds, please see Southall et al. 
(2007), Finneran and Jenkins (2012), Finneran (2015), and Table 5 in 
NMFS (2018).
    Installing piles requires a combination of impact pile driving, 
vibratory pile driving, and DTH drilling. For the project, these 
activities would not occur at the same time and there would likely be 
pauses in activities producing the sound during each day. Given these 
pauses and that many marine mammals are likely moving through the 
action area and not remaining for extended periods of time, the 
potential for TS declines.
    Behavioral Harassment--Exposure to noise from pile driving and 
removal and drilling also has the potential to behaviorally disturb 
marine mammals. Available studies show wide variation in response to 
underwater sound; therefore, it is difficult to predict specifically 
how any given sound in a particular instance might affect marine 
mammals perceiving the signal. If a marine mammal does react briefly to 
an underwater sound by changing its behavior or moving a small 
distance, the impacts of the change are unlikely to be significant to 
the individual, let alone the stock or population. However, if a sound 
source displaces marine mammals from an important feeding or breeding 
area for a prolonged period, impacts on individuals and populations 
could be significant (e.g., Lusseau and Bejder, 2007; Weilgart, 2007; 
NRC, 2005).
    Disturbance may result in changing durations of surfacing and 
dives, number of blows per surfacing, or

[[Page 18204]]

moving direction and/or speed; reduced/increased vocal activities; 
changing/cessation of certain behavioral activities (such as 
socializing or feeding); visible startle response or aggressive 
behavior (such as tail/fluke slapping or jaw clapping); avoidance of 
areas where sound sources are located. Pinnipeds may increase their 
haul-out time, possibly to avoid in-water disturbance (Thorson and 
Reyff, 2006). Behavioral responses to sound are highly variable and 
context-specific and any reactions depend on numerous intrinsic and 
extrinsic factors (e.g., species, state of maturity, experience, 
current activity, reproductive state, auditory sensitivity, time of 
day), as well as the interplay between factors (e.g., Richardson et 
al., 1995; Wartzok et al., 2003; Southall et al., 2007; Weilgart, 2007; 
Archer et al., 2010). Behavioral reactions can vary not only among 
individuals but also within an individual, depending on previous 
experience with a sound source, context, and numerous other factors 
(Ellison et al., 2012), and can vary depending on characteristics 
associated with the sound source (e.g., whether it is moving or 
stationary, number of sources, distance from the source). In general, 
pinnipeds seem more tolerant of, or at least habituate more quickly to, 
potentially disturbing underwater sound than do cetaceans, and 
generally seem to be less responsive to exposure to industrial sound 
than most cetaceans. Please see Appendices B and C of Southall et al. 
(2007) for a review of studies involving marine mammal behavioral 
responses to sound.
    Disruption of feeding behavior can be difficult to correlate with 
anthropogenic sound exposure, so it is usually inferred by observed 
displacement from known foraging areas, the appearance of secondary 
indicators (e.g., bubble nets or sediment plumes), or changes in dive 
behavior. As for other types of behavioral response, the frequency, 
duration, and temporal pattern of signal presentation, as well as 
differences in species sensitivity, are likely contributing factors to 
differences in response in any given circumstance (e.g., Croll et al., 
2001; Nowacek et al., 2004; Madsen et al., 2006; Yazvenko et al., 
2007). A determination of whether foraging disruptions incur fitness 
consequences would require information on or estimates of the energetic 
requirements of the affected individuals and the relationship between 
prey availability, foraging effort and success, and the life history 
stage of the animal.
    In 2016, the Alaska Department of Transportation and Public 
Facilities (ADOT&PF) documented observations of marine mammals during 
construction activities (i.e., pile driving and down-hole drilling) at 
the Kodiak Ferry Dock (see 80 FR 60636, October 7, 2015). In the marine 
mammal monitoring report for that project (ABR 2016), 1,281 Steller sea 
lions were observed within the Level B disturbance zone during pile 
driving or drilling (i.e., documented as Level B harassment take). Of 
these, 19 individuals demonstrated an alert behavior, 7 were fleeing, 
and 19 swam away from the project site. All other animals (98 percent) 
were engaged in activities such as milling, foraging, or fighting and 
did not change their behavior. In addition, two sea lions approached 
within 20 meters of active vibratory pile driving activities. Three 
harbor seals were observed within the disturbance zone during pile 
driving activities; none of them displayed disturbance behaviors. 
Fifteen killer whales and three harbor porpoise were also observed 
within the Level B harassment zone during pile driving. The killer 
whales were travelling or milling while all harbor porpoises were 
travelling. No signs of disturbance were noted for either of these 
species. Given the similarities in activities and habitat and the fact 
the same species are involved, we expect similar behavioral responses 
of marine mammals to GCHS's specified activity. That is, disturbance, 
if any, is likely to be temporary and localized (e.g., small area 
movements). Monitoring reports from other recent pile driving and DTH 
drilling projects in Alaska have observed similar behaviors (for 
example, the Biorka Island Dock Replacement Project).
    Masking--Sound can disrupt behavior through masking, or interfering 
with, an animal's ability to detect, recognize, or discriminate between 
acoustic signals of interest (e.g., those used for intraspecific 
communication and social interactions, prey detection, predator 
avoidance, navigation) (Richardson et al., 1995). Masking occurs when 
the receipt of a sound is interfered with by another coincident sound 
at similar frequencies and at similar or higher intensity, and may 
occur whether the sound is natural (e.g., snapping shrimp, wind, waves, 
precipitation) or anthropogenic (e.g., pile driving, shipping, sonar, 
seismic exploration) in origin. The ability of a noise source to mask 
biologically important sounds depends on the characteristics of both 
the noise source and the signal of interest (e.g., signal-to-noise 
ratio, temporal variability, direction), in relation to each other and 
to an animal's hearing abilities (e.g., sensitivity, frequency range, 
critical ratios, frequency discrimination, directional discrimination, 
age or TTS hearing loss), and existing ambient noise and propagation 
conditions. Masking of natural sounds can result when human activities 
produce high levels of background sound at frequencies important to 
marine mammals. Conversely, if the background level of underwater sound 
is high (e.g. on a day with strong wind and high waves), an 
anthropogenic sound source would not be detectable as far away as would 
be possible under quieter conditions and would itself be masked. The 
Juneau area contains active commercial shipping and ferry operations as 
well as numerous recreational and commercial vessels; therefore, 
background sound levels in the area are already elevated.
    Airborne Acoustic Effects--Pinnipeds that occur near the project 
site could be exposed to airborne sounds associated with pile driving 
and DTH drilling that have the potential to cause behavioral 
harassment, depending on their distance from pile driving activities. 
Cetaceans are not expected to be exposed to airborne sounds that would 
result in harassment as defined under the MMPA.
    Airborne noise would primarily be an issue for pinnipeds that are 
swimming or hauled out near the project site within the range of noise 
levels elevated above the acoustic criteria. We recognize that 
pinnipeds in the water could be exposed to airborne sound that may 
result in behavioral harassment when looking with their heads above 
water. Most likely, airborne sound would cause behavioral responses 
similar to those discussed above in relation to underwater sound. For 
instance, anthropogenic sound could cause hauled out pinnipeds to 
exhibit changes in their normal behavior, such as reduction in 
vocalizations, or cause them to temporarily abandon the area and move 
further from the source. However, these animals would previously have 
been `taken' because of exposure to underwater sound above the 
behavioral harassment thresholds, which are in all cases larger than 
those associated with airborne sound. Thus, the behavioral harassment 
of these animals is already accounted for in these estimates of 
potential take. Therefore, we do not believe that authorization of 
incidental take resulting from airborne sound for pinnipeds is 
warranted, and airborne sound is not discussed further here.

[[Page 18205]]

Marine Mammal Habitat Effects

    GCHS's construction activities at Sentinel Island could have 
localized, temporary impacts on marine mammal habitat and their prey by 
increasing in-water sound pressure levels and slightly decreasing water 
quality. Increased noise levels may affect acoustic habitat (see 
masking discussion above) and adversely affect marine mammal prey in 
the vicinity of the project area (see discussion below). During impact 
pile driving, elevated levels of underwater noise would ensonify Lynn 
Canal where both fishes and mammals occur and could affect foraging 
success. Currently, there are a few dozen annual vessel landings at 
Sentinel Island. With the new dock there would be up to two tour 
landings daily during the summer.
    Construction activities are of short duration and would likely have 
temporary impacts on marine mammal habitat through increases in 
underwater and airborne sound.
    In-water pile driving, and drilling activities would also cause 
short-term effects on water quality due to increased turbidity. Local 
strong currents are anticipated to disburse suspended sediments 
produced by project activities at moderate to rapid rates depending on 
tidal stage. GCHS would employ standard construction best management 
practices (BMPs; see section 11 in application), thereby reducing any 
impacts. Therefore, the impact from increased turbidity levels is 
expected to be discountable.

In-Water Construction Effects on Potential Foraging Habitat

    The area likely impacted by the project is relatively small 
compared to the available habitat in Lynn Canal (e.g., most of the 
impacted area is limited to the east side of Sentinel Island in the 
Favorite Channel) and does not include any BIAs. One ESA-designated 
critical habitat area for Steller sea lions is nearby on Benjamin 
Island and would be within the Level B harassment zone for sound but 
there would be no direct effects on the critical habitat. Pile 
installation and drilling may temporarily increase turbidity resulting 
from suspended sediments. Any increases would be temporary, localized, 
and minimal. GCHS must comply with state water quality standards during 
these operations by limiting the extent of turbidity to the immediate 
project area. In general, turbidity associated with pile installation 
is localized to about a 25-foot radius around the pile (Everitt et al., 
1980). Cetaceans are not expected to be close enough to the project 
pile driving areas to experience effects of turbidity, and any 
pinnipeds would be transiting the area and could avoid localized areas 
of turbidity. Therefore, the impact from increased turbidity levels is 
expected to be discountable to marine mammals. Furthermore, pile 
driving at the project site would not obstruct movements or migration 
of marine mammals.
    Avoidance by potential prey (i.e., fish) of the immediate area due 
to the temporary loss of this foraging habitat is also possible. The 
duration of fish avoidance of this area after pile driving stops is 
unknown, but a rapid return to normal recruitment, distribution and 
behavior is anticipated. Any behavioral avoidance by fish of the 
disturbed area would still leave significantly large areas of fish and 
marine mammal foraging habitat in the nearby vicinity in Lynn Canal and 
the project would occur outside the peak eulachon, capelin and salmonid 
runs.
    The duration of the construction activities is relatively short. 
The construction window is for a maximum of 4-5 months with only a 
maximum of 6 days of pile driving. During each day, construction 
activities would only occur during daylight hours. Impacts to habitat 
and prey are expected to be minimal based on the short duration of 
activities.
    In-water Construction Effects on Potential Prey (Fish)--
Construction activities would produce continuous (i.e., vibratory pile 
driving and DTH drilling) and pulsed (i.e. impact driving) sounds. Fish 
react to sounds that are especially strong and/or intermittent low-
frequency sounds. Short duration, sharp sounds can cause overt or 
subtle changes in fish behavior and local distribution. Hastings and 
Popper (2005) identified several studies that suggest fish may relocate 
to avoid certain areas of sound energy. Additional studies have 
documented effects of pile driving on fish, although several are based 
on studies in support of large, multiyear bridge construction projects 
(e.g., Scholik and Yan, 2001, 2002; Popper and Hastings, 2009). Sound 
pulses at received levels of 160 dB may cause subtle changes in fish 
behavior. SPLs of 180 dB may cause noticeable changes in behavior 
(Pearson et al., 1992; Skalski et al., 1992). SPLs of sufficient 
strength have been known to cause injury to fish and fish mortality.
    The most likely impact to fish from pile driving and drilling 
activities at the project area would be temporary behavioral avoidance 
of the area. The duration of fish avoidance of this area after pile 
driving stops is unknown, but a rapid return to normal recruitment, 
distribution and behavior is anticipated. In general, impacts to marine 
mammal prey species are expected to be minor and temporary due to the 
short timeframe for the project.
    Construction activities, in the form of increased turbidity, have 
the potential to adversely affect forage fish and juvenile salmonid 
outmigratory routes in the project area. Both herring and salmon form a 
significant prey base for Steller sea lions, herring is a primary prey 
species of humpback whales, and herring, capelin and salmon are 
components of the diet of many other marine mammal species that occur 
in the project area. Increased turbidity is expected to occur in the 
immediate vicinity (on the order of 10 feet or less) of construction 
activities. However, suspended sediments and particulates are expected 
to dissipate quickly within a single tidal cycle. Given the limited 
area affected and high tidal dilution rates any effects on forage fish 
and salmon are expected to be minor or negligible. In addition, best 
management practices would be in effect, which would limit the extent 
of turbidity to the immediate project area. Finally, exposure to turbid 
waters from construction activities is not expected to be different 
from the current exposure; fish and marine mammals in the Lynn Canal 
region are routinely exposed to substantial levels of suspended 
sediment from glacial sources.
    In summary, given the short daily duration of sound associated with 
individual pile driving and drilling events, the small number of total 
piles, and the relatively small areas being affected, pile driving and 
drilling activities associated with the proposed action are not likely 
to have a permanent, adverse effect on any fish habitat, or populations 
of fish species. Thus, we conclude that impacts of the specified 
activity are not likely to have more than short-term adverse effects on 
any prey habitat or populations of prey species. Further, any impacts 
to marine mammal habitat are not expected to result in significant or 
long-term consequences for individual marine mammals, or to contribute 
to adverse impacts on their populations.
Estimated Take
    This section provides an estimate of the number of incidental takes 
proposed for authorization through this IHA, which will inform both 
NMFS' consideration of ``small numbers'' and the negligible impact 
determination.
    Harassment is the only type of take expected to result from these 
activities. Except with respect to certain activities not pertinent 
here, section 3(18) of the

[[Page 18206]]

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 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 proposed to 
be authorized for this activity. Below we describe how the take is 
estimated.
    Generally speaking, we estimate take by considering: (1) Acoustic 
thresholds above which NMFS believes the best available science 
indicates marine mammals will be behaviorally harassed or incur some 
degree of permanent hearing impairment; (2) the area or volume of water 
that will be ensonified above these levels in a day; (3) the density or 
occurrence of marine mammals within these ensonified areas; and, (4) 
and the number of days of activities. We note that while these basic 
factors can contribute to a basic calculation to provide an initial 
prediction of takes, additional information that can qualitatively 
inform take estimates is also sometimes available (e.g., previous 
monitoring results or average group size). Below, we describe the 
factors considered here in more detail and present the proposed take 
estimate.

Acoustic Thresholds

    Using the best available science, NMFS has developed acoustic 
thresholds that identify the received level of underwater sound above 
which exposed marine mammals would be reasonably expected to be 
behaviorally harassed (equated to Level B harassment) or to incur PTS 
of some degree (equated to Level A harassment).
    Level B Harassment 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) (root mean square 
(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, drilling) and impulsive (impact pile-driving) 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 3. 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.
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.


[[Page 18207]]

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 vibratory pile driving we determined a source level of 161 dB 
(RMS SPL) at 10m was most appropriate. The closest known measurements 
of sound levels for vibratory pile installation of 16-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 used a source level of 166.2 dB (RMS SPL); 
this is derived from Denes et al. (2016), where they drilled 24-inch 
piles near Kodiak, AK. 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 (166.2dB) 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 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 4. 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 5).

                  Table 4--NMFS User Spreadsheet Inputs
------------------------------------------------------------------------
                         User spreadsheet input
-------------------------------------------------------------------------
                                     Vibratory pile
                                       driving/DTH        Impact pile
                                        drilling            driving
------------------------------------------------------------------------
Spreadsheet Tab Used.............  A.1) Vibratory      E.1) Impact pile
                                    pile driving.       driving.
Source Level.....................  166.2 dB RMS......  175 dB SS SEL.
Weighting Factor Adjustment (kHz)  2.5...............  2.
(a) Number of strikes per pile...  N/A...............  250.
(a) Activity Duration (h:min)      12:00.............  N/A.
 within 24-h period.
Propagation (xLogR)..............  15................  15.
Distance of source level           10................  10.
 measurement (meters).
Number of piles per day..........  2.................  2.
------------------------------------------------------------------------


                                       Table 5--NMFS User Spreadsheet Outputs: Level B and Level A (PTS) Isopleths
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                      Behavioral                                       PTS isopleths (meters)  (level A)
                                      disturbance    ---------------------------------------------------------------------------------------------------
            Activity                (level B)  all     Humpback + minke                         Harbor + dall's
                                        species             whales           Killer whales         porpoise          Harbor seals      Stellar sea lions
--------------------------------------------------------------------------------------------------------------------------------------------------------
Vibratory Driving/DTH drilling..  12.1 km (7.5        80 m (263 feet)...  7 m (23 feet).....  118 m (387 feet)..  48.3 m (159 feet).  4 m (13 feet)
                                   miles) *.
Impact Driving..................  1 km (3280 ft)....  184 m (605 ft)....  6.6 m (22 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 dB RMS are 
12.1 km (7.5 miles) miles for vibratory pile driving and 1 km (3280 ft) 
for impact driving. The enclosed nature of Lutak Inlet restricts the 
propagation of noise in all 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 all 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.

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.

[[Page 18208]]

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 6.
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. 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. Our take estimate is then the product of 
the number of individuals per day times the number of interactions per 
individual per day times the 6 days of the project, or 144 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 9 of the 144 takes 
will be of the Mexico DPS. However, the average group size in the area 
during the fall months was two whales (Dahlheim et al. 2009) and it is 
possible that a mother calf pair of the Mexico DPS, or other group of 
two Mexico DPS whales, may occur within the project area each day. Thus 
it is conservatively assumed that 12 individuals (2 individuals per 
day) of the threatened Mexico DPS population may be taken and 132 of 
the Hawaiian DPS.
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. 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. Take is 
estimated to be 134 seals times 7.5 in-water sightings per hour times 
36 hours of work, or 36,180 Level B takes.
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 zone 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 18209]]



         Table 6--Proposed Authorized Level A and B Take and Percent of MMPA Stock Proposed to Be Taken
----------------------------------------------------------------------------------------------------------------
                                                                             Proposed authorized take
                             Species                             -----------------------------------------------
                                                                      Level B         Level A       % of stock
----------------------------------------------------------------------------------------------------------------
Humpback Whale \1\..............................................             144               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 \2\.................................................          36,180               0             8.5
Steller Sea Lion (Eastern DPS) \3\..............................            1467               0             3.5
Steller Sea Lion (Western DPS) \3\..............................              21               0            0.04
----------------------------------------------------------------------------------------------------------------
\1\ Distribution of proposed take by ESA status is 88 Level B takes for Hawaii DPS and 8 Level B take for Mexico
  DPS.
\2\ Percent of stock taken is calculated assuming 804 unique individuals exposed, individuals are likely to be
  repeatedly counted as takes because of dive times of species.
\3\ Total estimated take of Steller sea lions was 992. 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 
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 possible 
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.
Proposed Mitigation
    In order to issue an IHA under Section 101(a)(5)(D) of the MMPA, 
NMFS must set forth the permissible methods of taking pursuant to 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.

[[Page 18210]]

    The following mitigation measures are proposed 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 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 7) 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 30-minute period. 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. In the 
unanticipated event that the specified activity clearly causes the take 
of a marine mammal in a manner prohibited by the IHA, such as serious 
injury or mortality, the protected species observer (PSO) on watch 
would immediately call for the cessation of the specified activities 
and immediately report the incident to the Chief of the Permits and 
Conservation Division, Office of Protected Resources, NMFS, and NMFS 
Alaska Regional Office;
     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 
elapsed since the last sighting; 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 preliminarily determined that the proposed 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 7--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/Drilling..............  80 m (265 ft).....  7 m (25 ft).......  120 m (395 ft)....  50 m (165 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).
--------------------------------------------------------------------------------------------------------------------------------------------------------

Proposed Monitoring and Reporting
    In order to issue an IHA for an activity, Section 101(a)(5)(D) of 
the MMPA states that NMFS must set forth requirements pertaining to the 
monitoring and reporting of such taking. The MMPA implementing 
regulations at 50 CFR 216.104 (a)(13) indicate that requests for 
authorizations must include the suggested means of accomplishing the 
necessary monitoring and reporting that will result in increased 
knowledge of the species and of the level of taking or impacts on 
populations of marine mammals that are expected to be present in the 
proposed action area. Effective reporting is critical both to 
compliance as well as ensuring that the most value is obtained from the 
required monitoring.
    Monitoring and reporting requirements prescribed by NMFS 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 
concert with distance from piles being

[[Page 18211]]

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 thirty 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 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 CVs 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; 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. 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.
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

[[Page 18212]]

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 6, 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, 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 
Proposed 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 preliminary determination that the impacts resulting from 
this activity are not expected to adversely affect the species or stock 
through effects on annual rates of recruitment or survival:
     No mortality 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 proposed monitoring and 
mitigation measures, NMFS preliminarily finds that the total marine 
mammal take from the proposed activity will have a negligible impact on 
all affected marine mammal species or stocks.
Small Numbers
    As noted above, only small numbers of incidental take may be 
authorized under 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. 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 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 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 proposed mitigation and monitoring measures) and the 
anticipated take of marine mammals, NMFS preliminarily finds that small 
numbers of marine mammals will be taken relative to the population size 
of 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

[[Page 18213]]

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 preliminarily 
determined that there will not be an unmitigable adverse impact on 
subsistence uses from GCHS's planned activities.
Endangered Species Act (ESA)
    Section 7(a)(2) of the Endangered Species Act of 1973 (ESA: 16 
U.S.C. 1531 et seq.) requires that each Federal agency insure that any 
action it authorizes, funds, or carries out is not likely to jeopardize 
the continued existence of any endangered or threatened species or 
result in the destruction or adverse modification of designated 
critical habitat. To ensure 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 Permits and 
Conservation Division has requested initiation of Section 7 
consultation with the Alaska Region for the issuance of this IHA. NMFS 
will conclude the ESA consultation prior to reaching a determination 
regarding the proposed issuance of the authorization.
Proposed Authorization
    As a result of these preliminary determinations, NMFS proposes to 
issue an IHA to GCHS for conducting the Sentinel Island Moorage Float 
project near Juneau, Alaska between July 20, 2020 and July 19, 2021, 
provided the previously mentioned mitigation, monitoring, and reporting 
requirements are incorporated. A draft of the proposed IHA can be found 
at https://www.fisheries.noaa.gov/permit/incidental-take-authorizations-under-marine-mammal-protection-act.
Request for Public Comments
    We request comment on our analyses, the proposed authorization, and 
any other aspect of this Notice of Proposed IHA for the proposed 
Sentinel Island Moorage Float project. We also request at this time 
comment on the potential renewal of this proposed IHA as described in 
the paragraph below. Please include with your comments any supporting 
data or literature citations to help inform decisions on the request 
for this IHA or a subsequent Renewal IHA.
    On a case-by-case basis, NMFS may issue a one-year Renewal IHA 
following notice to the public providing an additional 15 days for 
public comments when (1) up to another year of identical, or nearly 
identical, activities as described in the Detailed Description of 
Specific Activity section of this notice is planned or (2) the 
activities as described in the Detailed Description of Specific 
Activity section of this notice would not be completed by the time the 
IHA expires and a Renewal would allow for completion of the activities 
beyond that described in the Dates and Duration section of this notice, 
provided all of the following conditions are met:
     A request for renewal is received no later than 60 days 
prior to the needed Renewal IHA effective date (recognizing that 
Renewal IHA expiration date cannot extend beyond one year from 
expiration of the initial IHA).
     The request for renewal must include the following:
    (1) An explanation that the activities to be conducted under the 
requested Renewal IHA are identical to the activities analyzed under 
the initial IHA, are a subset of the activities, or include changes so 
minor (e.g., reduction in pile size) that the changes do not affect the 
previous analyses, mitigation and monitoring requirements, or take 
estimates (with the exception of reducing the type or amount of take).
    (2) A preliminary monitoring report showing the results of the 
required monitoring to date and an explanation showing that the 
monitoring results do not indicate impacts of a scale or nature not 
previously analyzed or authorized.
     Upon review of the request for Renewal, the status of the 
affected species or stocks, and any other pertinent information, NMFS 
determines that there are no more than minor changes in the activities, 
the mitigation and monitoring measures will remain the same and 
appropriate, and the findings in the initial IHA remain valid.

    Dated: March 27, 2020.
Donna S. Wieting,
Director, Office of Protected Resources, National Marine Fisheries 
Service.
[FR Doc. 2020-06787 Filed 3-31-20; 8:45 am]
 BILLING CODE 3510-22-P