[Federal Register Volume 85, Number 204 (Wednesday, October 21, 2020)]
[Notices]
[Pages 66939-66956]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2020-23304]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

[RTID 0648-XA554]


Takes of Marine Mammals Incidental to Specified Activities; 
Taking Marine Mammals Incidental to the U.S. Coast Guard's Base Los 
Angeles/Long Beach Wharf Expansion Project, Los Angeles, California

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 the U.S. Coast Guard (Coast 
Guard) for authorization to take marine mammals incidental to the Base 
Los Angeles/Long Beach Wharf Expansion Project in Los Angeles, 
California. 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 November 
20, 2020.

ADDRESSES: Comments should be addressed to Jolie Harrison, Chief, 
Permits and Conservation Division, Office of Protected Resources, 
National Marine Fisheries Service. Comments should be sent to 
[email protected].
    Instructions: NMFS is not responsible for comments sent by any 
other method, to any other address or individual, or received after the 
end of the comment period. Comments received electronically, including 
all attachments, must not exceed a 25-megabyte file size. Attachments 
to electronic comments will be accepted in Microsoft Word or Excel or 
Adobe PDF file formats only. All comments received are a part of the 
public record and will generally be posted online at 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.
    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 IHA) 
with respect to potential impacts on the human environment.
    This action is consistent with categories of activities identified 
in Categorical Exclusion B4 (IHAs with no anticipated serious injury or 
mortality) of the Companion Manual for NOAA Administrative Order 216-
6A, which do not individually or cumulatively have the potential for 
significant impacts on the quality of the human environment and for 
which we have not identified any extraordinary circumstances that would 
preclude this categorical exclusion. Accordingly, NMFS has 
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 July 2, 2020, NMFS received an application from the Coast Guard 
requesting an IHA to take small numbers of five species of marine 
mammals incidental to pile driving associated with the Base Los Angeles 
Long Beach Wharf Expansion Project in Los Angeles, California. The 
application was deemed adequate and complete on October 5, 2020. The 
Coast Guard's request is for take of a small number of five species of 
marine mammals by Level A and/or Level B harassment. Neither the Coast 
Guard nor NMFS expects serious injury or mortality to result from this 
activity and, therefore, an IHA is appropriate.

Description of Proposed Activity

Overview

    The purpose of the project is to expand the existing wharf and 
other base infrastructure for hosting two additional offshore patrol 
cutters. The existing 1255-foot (383 meters (m)) long

[[Page 66940]]

by 30-foot (9 m) wide wharf will be extended 265 feet (81 m). The 
waterfront improvements also include repair of the bank erosion area 
and placement of small rocks for slope protection near the new onshore 
electrical substation. Specifically, construction work includes 
installing up to 102 pier support piles (16 to 30-inch diameter 
concrete piles) and 126 fender and corner protection piles (16 to 30-
inch diameter concrete piles). Pile driving will be by impact 
hammering.
    The pile driving can result in take of marine mammals from sound in 
the water which results in behavioral harassment or auditory injury.

Dates and Duration

    The work described here is scheduled for February 1, 2021 through 
January 31, 2022. Because of other permitting restrictions, in-water 
pile driving can only occur between September 1 and April 14, to avoid 
the nesting season of the California least tern.

Specific Geographic Region

    The project site is located in the Port of Los Angeles (Figure 1). 
The Port of Los Angeles is bounded by hard structure breakwaters and 
riprap lined, mostly artificial islands. It is a highly industrialized 
port (the busiest container seaport in the United States) and is 
located immediately west of the Port of Long Beach, the second-busiest 
container seaport in the United States. Coast Guard Base Los Angeles/
Long Beach is located on 27 acres (0.11 square kilometers (km)) of 
Federal government[hyphen]owned land on the southern tip of Terminal 
Island within the Los Angeles port and harbor at the mouth of the Main 
Channel. The port geography and breakwaters limit the effects of 
construction sound to within the port boundaries. Base Los Angeles/Long 
Beach currently has three wharf piers along its western boundary that 
serve as the home port for a buoy tender, four fast response cutters, 
and seven small boats. The extension of the piers will lengthen the 
existing structure to the south towards the harbor entrance.
    The port is heavily used by commercial, recreational, and military 
vessels. Tetra Tech (2011) reported the underwater ambient noise levels 
in active shipping areas were approximately 140 decibels (dB) re: 1 
micropascal ([micro]Pa) root mean square (rms) and noise levels in non-
shipping areas were between 120 dB re: 1 [micro]Pa (rms) and 132 re: 1 
[micro]Pa (rms). These underwater ambient noise levels are typical of a 
large marine bay with heavy commercial boat traffic (Buehler et al. 
2015). Ship noise in the ports may mask underwater sounds produced by 
the proposed activities, and project noises will likely become 
indistinguishable from other background noise as they attenuate to near 
ambient sound pressure levels moving away from the project site.
BILLING CODE 3510-22-P
[GRAPHIC] [TIFF OMITTED] TN21OC20.000


[[Page 66941]]


BILLING CODE 3510-22-C

Detailed Description of Specific Activity

    The contracting for the project will be a design build contract 
that has not yet been awarded. Therefore, the Coast Guard does not 
currently have finalized plans for the project. Consequently the Coast 
Guard has provided a number of construction scenarios we will use to 
calculate possible effects of the project and determine potential 
marine mammal harassment zones, shutdown zones, and take. We will take 
a conservative worst case approach by analyzing the loudest sounds 
(from the largest possible diameter piles) and the longest possible 
duration of sound generation (from installing smaller but more numerous 
and time-consuming piles) and generally the methods that would most 
impact marine mammals. Meeting our statutory and regulatory burdens to 
issue an IHA for this worst case condition assures that whatever 
project design configuration is ultimately selected will also meet 
these burdens. It is possible the contract will be awarded by the time 
this IHA is finalized. Therefore, we consider the Coast Guard's range 
of construction options herein as we may be able to narrow the range of 
impacts by the issuance of the final IHA.
    The wharf extension will be supported by concrete piles that may 
vary in diameter from 16 to 30 inches under the different construction 
options. If 16-inch pies are used the Coast Guard estimates the project 
will require up to 102 piles to support the wharf. If 30-inch piles are 
used the Coast Guard estimates up to 54 piles will be required. In 
addition to the support piles, up to 108 additional concrete piles (up 
to 30-inch diameter) will be used to construct fenders and a further 18 
concrete piles (up to 30-inch diameter) will be installed as corner 
protection at the end of the wharf.
    The pile driving and excavation equipment will most likely be 
deployed and operated from barges, on water. A temporary construction 
staging area would be designated on shore in the vicinity, and 
construction barges would transport materials and crew to the work site 
from a local pier. The Coast Guard will use a bubble curtain to reduce 
sounds (e.g., pneumatic barrier typically comprised of hosing or PVC 
piping that disrupts underwater noise propagation; see Proposed 
Mitigation section below).
    In addition to the in-water work, the project includes onshore work 
including a new Maintenance and Weapons Division building, 
modifications to two other buildings, new and refurbished parking, and 
associated site and utility work. None of this work is expected to 
affect marine mammals and is not considered further. The waterfront 
improvements also include repair of the bank erosion area and placement 
of rock slope protection consisting of small rock near the new onshore 
electrical substation. None of this waterfront work is expected to 
affect marine mammals either and is not considered further.
    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 or stocks for which take is expected and 
proposed to be authorized for this action, and summarizes information 
related to the population or stock, including regulatory status under 
the MMPA and ESA and potential biological removal (PBR), where known. 
For taxonomy, we follow Committee on Taxonomy (2020). 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. Pacific SARs (e.g., Carretta et al. 2020).

                    Table 1--Species That Spatially Co-Occur With the Activity to the Degree That Take Is Reasonably Likely To Occur
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                                                                                         ESA/MMPA status;    Stock abundance (CV,
             Common name                  Scientific name               Stock             Strategic (Y/N)      Nmin, most recent       PBR     Annual M/
                                                                                                \1\          abundance survey) \2\               SI \3\
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                                          Order Cetartiodactyla--Cetacea--Superfamily Mysticeti (baleen whales)
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Family Eschrichtiidae:
    Gray Whale......................  Eschrichtius robustus..  Eastern North Pacific..  -, -, N             26,960 (0.05, 25,849,         801        138
                                                                                                             2016).
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                            Order Cetartiodactyla--Cetacea--Superfamily Odontoceti (toothed whales, dolphins, and porpoises)
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Family Delphinidae:
    Bottlenose Dolphin..............  Tursiops truncatus.....  California Coastal.....  -, -, N             453 (0.06, 346, 2011).        2.7       >2.0
    Short-beaked common dolphin.....  Delphinus delphis......  California/Oregon/       -, -, N             969,861 (0.17,              8,393       >=40
                                                                Washington.                                  839,325, 2016).
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                                                         Order Carnivora--Superfamily Pinnipedia
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Family Otariidae (eared seals and
 sea lions):

[[Page 66942]]

 
    California Sea Lion.............  Zalophus californianus.  United States..........  -, -, N             257,606 (N/A, 233,515,     14,011       >321
                                                                                                             2014).
Family Phocidae (earless seals):
    Harbor seal.....................  Phoca vitulina.........  California.............  -, -, N             30,968 (N/A, 27,348,        1,641         43
                                                                                                             2012).
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\1\ Endangered Species Act (ESA) status: Endangered (E), Threatened (T)/MMPA status: Depleted (D). A dash (-) indicates that the species is not listed
  under the ESA or designated as depleted under the MMPA. Under the MMPA, a strategic stock is one for which the level of direct human-caused mortality
  exceeds PBR or which is determined to be declining and likely to be listed under the ESA within the foreseeable future. Any species or stock listed
  under the ESA is automatically designated under the MMPA as depleted and as a strategic stock.
\2\ NMFS marine mammal 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.
\3\ These values, found in NMFS's SARs, represent annual levels of human-caused mortality plus serious injury from all sources combined (e.g.,
  commercial fisheries, ship strike). Annual Mortality/Serious Injury (M/SI) often cannot be determined precisely and is in some cases presented as a
  minimum value or range. A CV associated with estimated mortality due to commercial fisheries is presented in some cases.

    California sea lion, harbor seal, and bottlenose dolphin spatially 
co-occur with the activity to the degree that take is reasonably likely 
to occur, and we have proposed authorizing take of these species. 
Short-beaked common dolphin and gray whale occurrence and density is 
such that take is possible, and we have proposed authorizing take of 
these species also. These are all the species that have been observed 
in Los Angeles harbor in three surveys over 14 years (MEC, 2002; SAIC, 
2010; MBC, 2016).
    Blue whale, fin whale, Risso's dolphin, Pacific white-sided 
dolphin, and northern right whale dolphin occur in the region, but are 
rare and have not been observed in the project area, so take is not 
expected to occur and they are not discussed further beyond the 
explanation provided here. Blue whales have been observed in the 
Southern California Bight during their fall migration, however the 
closest live blue whale sighting record is 10 km south of the project 
site. Fin whales occur in the Southern California Bight year round, 
although they also seasonally range to central California and Baja 
California before returning to the Southern California Bight (Falcone 
and Schorr, 2013). The California, Oregon, and Washington (CA/OR/WA) 
stock of Risso's dolphins is commonly observed in the Southern 
California Bight (Carretta et al., 2020), however they are infrequently 
observed very close to shore. The CA/OR/WA stock of Pacific white-sided 
dolphin is seasonally present in colder months outside the port 
breakwater in offshore water. Given that there have been no sightings 
of Pacific white-sided dolphins in the port and that the noise produced 
by the proposed project's in-water activities are not anticipated to 
propagate outside the port, no takes are anticipated for Pacific white-
sided dolphins. The CA/OR/WA stock of northern right whale dolphins 
rarely occurs nearshore in the Southern California Bight (Carretta et 
al., 2020). The closest northern right whale dolphin sighting record is 
26.5 km southwest of the Port of Los Angeles breakwater (OBIS SEAMAP, 
2019).

Gray Whale

    In the fall, gray whales migrate from their summer feeding grounds, 
heading south along the coast of North America to spend the winter in 
their breeding and calving areas off the coast of Baja California, 
Mexico. From mid-February to May, the Eastern North Pacific stock of 
gray whales can be seen migrating northward with newborn calves along 
the west coast of the U.S. During the migration, gray whales will 
occasionally enter rivers and bays and even harbors along the coast but 
not in high numbers. They travel alone or in small groups. There is 
currently a gray whale unusual mortality event that has led to 
increased strandings along the west coast (https://www.fisheries.noaa.gov/national/marine-life-distress/2019-2020-gray-whale-unusual-mortality-event-along-west-coast-and).
    Gray whales are periodically, but not regularly sighted within the 
Los Angeles and Long Beach harbor area. No Gray whales were sighted 
during the 2013 to 2014 or 2008 biological baseline surveys of the 
harbors. One small gray whale, and later a dead gray whale, was 
observed inside the harbor areas during the 2000 survey (MEC, 2002; 
SAIC, 2010; MBC, 2016).

Bottlenose Dolphin

    The California coastal stock of common bottlenose dolphin is found 
within 0.6 miles (mi) (1 km) of shore (Defran and Weller, 1999) and 
occurs from northern Baja California, Mexico to Bodega Bay, CA. Their 
range has extended north over the last several decades with El 
Ni[ntilde]o events and increased ocean temperatures (Hansen and Defran, 
1990). Genetic studies have shown that no mixing occurs between the 
California coastal stock and the offshore common bottlenose dolphin 
stock (Lowther-Thieleking et al., 2015). Bottlenose dolphins are 
opportunistic foragers: time of day, tidal state, and oceanographic 
habitat influence where they pursue prey (Hanson and Defran, 1993). 
Dive durations up to 15 minutes have been recorded for trained Navy 
bottlenose dolphins, (Ridgway et al., 1969), but typical dives are 
shallower and of a much shorter duration (Mate et al., 1995).
    Bottlenose dolphins accounted for approximately two percent of all 
marine mammal observations during the most recent survey of the Los 
Angeles and Long Beach harbors. The majority of observations involved 
individuals foraging in the outer harbor area (MBC, 2016).

Short-Beaked Common Dolphin

    Common dolphins occur in temperate and tropical waters globally. 
Short beaked common dolphins from the CA/WA/OR stock are the most 
common cetacean off the coast of California, occurring year-round and 
ranging from the coast to at least 300 nautical miles (nm) offshore 
(Carretta et al., 2019). They travel in large social pods and are 
generally associated with oceanic and offshore waters, prey-rich ocean 
upwellings, and underwater landscape features such as seamounts, 
continental shelves, and oceanic ridges. Though they are present off 
the coast of California year-round, their abundance varies with 
seasonal and interannual changes in oceanographic conditions 
(increasing with higher temperatures) with peak abundance in the summer 
and fall (Forney and Barlow, 1998; Barlow, 2016). Common dolphins 
largely forage on schooling fish and squid. Off the California coast, 
calving takes place in winter months.

[[Page 66943]]

    Abundance of the CA/OR/WA stock of short-beaked common dolphins has 
increased since large-scale surveys began in 1991. This stock is known 
to increase in abundance in California during warm water periods. The 
most recent survey in 2014 survey was conducted during extremely warm 
oceanic conditions (Bond et al., 2015) and recorded the highest 
abundance estimate since large-scale surveys began. This observed 
increase in abundance of short-beaked common dolphins off California 
likely reflects a northward movement of this transboundary stock from 
waters off Mexico (distributional shift), rather than an overall 
population increase due to growth shift (Anganuzzi et al., 1993; 
Barlow, 1995; Barlow, 2016; Forney and Barlow, 1998).
    Observations during biological surveys in 2013 through 2014 
included one pod of 40 individuals in the Los Angeles Main Channel 
where the project occurs (MBC, 2016).

California Sea Lion

    California sea lions occur from Vancouver Island, British Columbia, 
to the southern tip of Baja California. Sea lions breed on the offshore 
islands of southern and central California from May through July (Heath 
and Perrin, 2008). During the non-breeding season, adult and subadult 
males and juveniles migrate northward along the coast to central and 
northern California, Oregon, Washington, and Vancouver Island 
(Jefferson et al., 1993). They return south the following spring (Heath 
and Perrin 2008, Lowry and Forney 2005). Females and some juveniles 
tend to remain closer to rookeries (Antonelis et al., 1990; Melin et 
al., 2008). Pupping occurs primarily on the California Channel Islands 
from late May until the end of June (Peterson and Bartholomew 1967). 
Weaning and mating occur in late spring and summer during the peak 
upwelling period (Bograd et al., 2009). After the mating season, adult 
males migrate northward to feeding areas as far away as the Gulf of 
Alaska (Lowry et al., 1992), and they remain away until spring (March-
May), when they migrate back to the breeding colonies. Adult females 
generally remain south of Monterey Bay, California throughout the year, 
feeding in coastal waters in the summer and offshore waters in the 
winter, alternating between foraging and nursing their pups on shore 
until the next pupping/breeding season (Melin and DeLong, 2000; Melin 
et al., 2008).
    California sea lions were the most commonly observed marine mammal 
during the 2008 and 2013 to 2014 surveys of the Los Angeles and Long 
Beach harbors. Individuals were observed hauled-out and resting on 
buoys, docks, riprap shorelines, as well as docked cargo ships. They 
were frequently documented to be foraging near bait barges and fish 
markets, as well as in the wakes of fishing boats entering the Port 
Complex (SAIC, 2010; MBC. 2016).

Harbor Seal

    Harbor seals are found from Baja California to the eastern Aleutian 
Islands of Alaska (Harvey and Goley, 2011). In California there are 
approximately 500 haulout sites along the mainland and on offshore 
islands, including intertidal sandbars, rocky shores, and beaches 
(Hanan, 1996; Lowry et al., 2008). Harbor seals molt from May through 
June. Peak numbers of harbor seals haul out during late May to July, 
which coincides with the peak molt. During both pupping and molting 
seasons, the number of seals and the length of time hauled out per day 
increase, from an average of 7 hours per day to 10-12 hours (Harvey and 
Goley, 2011; Huber et al., 2001; Stewart and Yochem, 1994).
    Harbor seals tend to forage at night and haul out during the day 
with a peak in the afternoon between 1 p.m. and 4 p.m. (Grigg et al., 
2012; London et al., 2001; Stewart and Yochem, 1994; Yochem et al., 
1987). Tide levels affect the maximum number of seals hauled out, with 
the largest number of seals hauled out at low tide, but time of day and 
season have the greatest influence on haul out behavior (Manugian et 
al., 2017; Patterson and Acevedo-Guti[eacute]rrez, 2008; Stewart and 
Yochem, 1994).
    Pupping occurs from March through May in central California (Codde 
and Allen, 2018). Pups are weaned in four weeks, most by mid-June 
(Codde and Allen, 2018). Harbor seals breed between late March and June 
(Greig and Allen, 2015). Harbor seals are rarely found more than 10.8 
nm from shore (Baird 2001) and are generally non-migratory (Burns, 
2002; Jefferson et al., 2008) and solitary at sea.
    In the Los Angeles and Long Beach Harbors, Pacific harbor seals 
were the second most abundant marine mammal, accounting for 
approximately 26 percent of marine mammal observations. They were more 
commonly observed in the outer harbor areas, resting or foraging along 
riprap shorelines, particularly in the vicinity of the outer harbor 
breakwaters (SAIC, 2010; MBC, 2016).

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        7 Hz to 35 kHz.
 (baleen whales).
Mid-frequency (MF) cetaceans        150 Hz to 160 kHz.
 (dolphins, toothed whales, beaked
 whales, bottlenose whales).
High-frequency (HF) cetaceans       275 Hz to 160 kHz.
 (true porpoises, Kogia, river
 dolphins, cephalorhynchid,
 Lagenorhynchus cruciger & L.
 australis).

[[Page 66944]]

 
Phocid pinnipeds (PW) (underwater)  50 Hz to 86 kHz.
 (true seals).
Otariid pinnipeds (OW)              60 Hz to 39 kHz.
 (underwater) (sea lions and fur
 seals).
------------------------------------------------------------------------
* Represents the generalized hearing range for the entire group as a
  composite (i.e., all species within the group), where individual
  species' hearing ranges are typically not as broad. Generalized
  hearing range chosen based on ~65 dB threshold from normalized
  composite audiogram, with the exception for lower limits for LF
  cetaceans (Southall et al. 2007) and PW pinniped (approximation).

    The pinniped functional hearing group was modified from Southall et 
al. (2007) on the basis of data indicating that phocid species have 
consistently demonstrated an extended frequency range of hearing 
compared to otariids, especially in the higher frequency range 
(Hemil[auml] et al., 2006; Kastelein et al., 2009; Reichmuth and Holt, 
2013).
    For more detail concerning these groups and associated frequency 
ranges, please see NMFS (2018) for a review of available information. 
Harbor seals are in the phocid group, California sea lions are in the 
otariid group, the dolphins are mid-frequency cetaceans, and gray 
whales are classified as low-frequency cetaceans.

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.
    Acoustic effects on marine mammals during the specified activity 
can occur from impact pile driving. The effects of underwater noise 
from the Coast Guard's proposed activities have the potential to result 
in Level A and/or Level B harassment of marine mammals in the action 
area.

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. The sounds produced by these activities 
fall into one of the 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).
    An impact pile hammer would be used on this project. 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).
    The likely or possible impacts of the Coast Guard'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 and sedimentation from 
the work; 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.

Acoustic Impacts

    The introduction of anthropogenic noise into the aquatic 
environment from pile driving is the primary means by which marine 
mammals may be harassed from the Coast Guard'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 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 non-observable physiological 
responses such an increase in stress hormones. Additional

[[Page 66945]]

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 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 et 
al., 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, 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 
2,760 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 for this project requires impact pile driving. 
There would likely be pauses in activities producing the sound during 
each day as work moves among piles and to adjust during the course of a 
single pile. 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 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 moving direction and/or speed; 
reduced/increased vocal activities; changing/cessation of certain 
behavioral activities (such as socializing or feeding); visible startle 
response or

[[Page 66946]]

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) 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 that some of the same species are 
involved, we expect similar behavioral responses of marine mammals to 
the Coast Guard's specified activity. That is, disturbance, if any, is 
likely to be temporary and localized (e.g., small area movements).
    Stress responses--An animal's perception of a threat may be 
sufficient to trigger stress responses consisting of some combination 
of behavioral responses, autonomic nervous system responses, 
neuroendocrine responses, or immune responses (e.g., Seyle 1950; Moberg 
2000). In many cases, an animal's first and sometimes most economical 
(in terms of energetic costs) response is behavioral avoidance of the 
potential stressor. Autonomic nervous system responses to stress 
typically involve changes in heart rate, blood pressure, and 
gastrointestinal activity. These responses have a relatively short 
duration and may or may not have a significant long-term effect on an 
animal's fitness.
    Neuroendocrine stress responses often involve the hypothalamus-
pituitary-adrenal system. Virtually all neuroendocrine functions that 
are affected by stress--including immune competence, reproduction, 
metabolism, and behavior--are regulated by pituitary hormones. Stress-
induced changes in the secretion of pituitary hormones have been 
implicated in failed reproduction, altered metabolism, reduced immune 
competence, and behavioral disturbance (e.g., Moberg 1987; Blecha 
2000). Increases in the circulation of glucocorticoids are also equated 
with stress (Romano et al., 2004).
    The primary distinction between stress (which is adaptive and does 
not normally place an animal at risk) and ``distress'' is the cost of 
the response. During a stress response, an animal uses glycogen stores 
that can be quickly replenished once the stress is alleviated. In such 
circumstances, the cost of the stress response would not pose serious 
fitness consequences. However, when an animal does not have sufficient 
energy reserves to satisfy the energetic costs of a stress response, 
energy resources must be diverted from other functions. This state of 
distress will last until the animal replenishes its energetic reserves 
sufficient to restore normal function.
    Relationships between these physiological mechanisms, animal 
behavior, and the costs of stress responses are well-studied through 
controlled experiments and for both laboratory and free-ranging animals 
(e.g., Holberton et al., 1996; Hood et al., 1998; Jessop et al., 2003; 
Krausman et al., 2004; Lankford et al., 2005). Stress responses due to 
exposure to anthropogenic sounds or other stressors and their effects 
on marine mammals have also been reviewed (Fair and Becker 2000; Romano 
et al., 2002b) and, more rarely, studied in wild populations (e.g., 
Romano et al., 2002a). For example, Rolland et al. (2012) found that 
noise reduction from reduced ship traffic in the Bay of Fundy was 
associated with decreased stress in North Atlantic right whales. These 
and other studies lead to a reasonable expectation that some marine 
mammals will experience physiological stress responses upon exposure to 
acoustic stressors and that it is possible that some of these would be 
classified as ``distress.'' In addition, any animal experiencing TTS 
would likely also experience stress responses (NRC, 2003), however 
distress is an unlikely result of this project based on observations of 
marine mammals during previous, similar projects in the area.
    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

[[Page 66947]]

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 project area 
contains active commercial shipping, as well as numerous recreational 
and other commercial vessels; therefore, background sound levels in the 
area are already elevated as noted above.
    Airborne Acoustic Effects--Pinnipeds that occur near the project 
site could be exposed to airborne sounds associated with pile driving 
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.

Marine Mammal Habitat Effects

    The Coast Guard's construction activities 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 the port 
and harbor where both fishes and mammals occur and could affect 
foraging success. Additionally, marine mammals may avoid the area 
during construction, however, displacement due to noise is expected to 
be temporary and is not expected to result in long-term effects to the 
individuals or populations. Construction activities are of short 
duration and would likely have temporary impacts on marine mammal 
habitat through increases in underwater and airborne sound.
    A temporary and localized increase in turbidity near the seafloor 
would occur in the immediate area surrounding the area where piles are 
installed. In general, turbidity associated with pile installation is 
localized to about a 25-foot (7.6-meter) radius around the pile 
(Everitt et al. 1980). Cetaceans are not expected to be close enough to 
the pile driving areas to experience effects of turbidity, and any 
pinnipeds could avoid localized areas of turbidity. Local strong 
currents are anticipated to disburse any additional suspended sediments 
produced by project activities at moderate to rapid rates depending on 
tidal stage. Therefore, we expect the impact from increased turbidity 
levels to be discountable to marine mammals and do not discuss it 
further.

In-Water Construction Effects on Potential Foraging Habitat

    The area likely impacted by the project is relatively small 
compared to the available habitat (e.g., the impacted area is entirely 
within the port) and does not include any Biologically Important Areas 
or other habitat of known importance. The area is highly influenced by 
anthropogenic activities. The total seafloor area affected by pile 
installation is a very small area compared to the vast foraging area 
available to marine mammals in the port and nearby ocean. At best, the 
impact area provides marginal foraging habitat for marine mammals and 
fish, while the new pilings installed would provide substrate for 
invertebrate prey to settle on. Furthermore, pile driving and removal 
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-water Construction Effects on Potential Prey--Sound may affect 
marine mammals through impacts on the abundance, behavior, or 
distribution of prey species (e.g., crustaceans, cephalopods, fish, 
zooplankton). Marine mammal prey varies by species, season, and 
location. Here, we describe studies regarding the effects of noise on 
known marine mammal prey.
    Fish utilize the soundscape and components of sound in their 
environment to perform important functions such as foraging, predator 
avoidance, mating, and spawning (e.g., Zelick and Mann, 1999; Fay, 
2009). Depending on their hearing anatomy and peripheral sensory 
structures, which vary among species, fishes hear sounds using pressure 
and particle motion sensitivity capabilities and detect the motion of 
surrounding water (Fay et al., 2008). The potential effects of noise on 
fishes depends on the overlapping frequency range, distance from the 
sound source, water depth of exposure, and species-specific hearing 
sensitivity, anatomy, and physiology. Key impacts to fishes may include 
behavioral responses, hearing damage, barotrauma (pressure-related 
injuries), and mortality.
    Fish react to sounds which are especially strong and/or 
intermittent low-frequency sounds, and behavioral responses such as 
flight or avoidance are the most likely effects. Short duration, sharp 
sounds can cause overt or subtle changes in fish behavior and local 
distribution. The reaction of fish to noise depends on the 
physiological state of the fish, past exposures, motivation (e.g., 
feeding, spawning, migration), and other environmental factors. 
Hastings and Popper (2005) identified several studies that suggest fish 
may relocate to avoid certain areas of sound energy. Additional studies 
have documented effects of pile driving on fish, although several are 
based on studies in support of large, multiyear bridge construction

[[Page 66948]]

projects (e.g., Scholik and Yan, 2001, 2002; Popper and Hastings, 
2009). Several studies have demonstrated that impulse sounds might 
affect the distribution and behavior of some fishes, potentially 
impacting foraging opportunities or increasing energetic costs (e.g., 
Fewtrell and McCauley, 2012; Pearson et al., 1992; Skalski et al., 
1992; Santulli et al., 1999; Paxton et al., 2017). However, some 
studies have shown no or slight reaction to impulse sounds (e.g., Pena 
et al., 2013; Wardle et al., 2001; Jorgenson and Gyselman, 2009; Cott 
et al., 2012).
    Sound Pressure Levels (SPL) of sufficient strength have been known 
to cause injury to fish and fish mortality. However, in most fish 
species, hair cells in the ear continuously regenerate and loss of 
auditory function likely is restored when damaged cells are replaced 
with new cells. Halvorsen et al. (2012a) showed that a TTS of 4-6 dB 
was recoverable within 24 hours for one species. Impacts would be most 
severe when the individual fish is close to the source and when the 
duration of exposure is long. Injury caused by barotrauma can range 
from slight to severe and can cause death, and is most likely for fish 
with swim bladders. Barotrauma injuries have been documented during 
controlled exposure to impact pile driving (Halvorsen et al., 2012b; 
Casper et al., 2013).
    The most likely impact to fish from pile driving activities 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.
    Construction activities, in the form of increased turbidity, have 
the potential to adversely affect fish migratory routes in the project 
area. These fish form a significant prey base for many marine mammal 
species that occur in the project area. Increased turbidity is expected 
to occur in the immediate vicinity of pile driving activities. Most of 
the turbidity is expected to be within the dredged navigation channel 
and port. Suspended sediments and particulates are expected to 
dissipate quickly within a single tidal cycle (Navy, 2018). Given the 
limited area affected and tidal dilution rates any effects on fish are 
expected to be minor or negligible. Finally, exposure to turbid waters 
from construction activities is not expected to be different from the 
current exposure; fish and marine mammals in the area are routinely 
exposed to substantial levels of suspended sediment from natural and 
anthropogenic sources (Tetra Tech, 2011).
    In summary, given the short daily duration of sound associated with 
individual pile driving events and the relatively small areas being 
affected, pile driving activities associated with the proposed action 
are not likely to have a permanent, adverse effect on any fish habitat, 
or populations of fish species. 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. 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 the IHA, which will inform both 
NMFS' consideration of ``small numbers'' and the negligible impact 
determination.
    Harassment is the only type of take expected to result from these 
activities. Except with respect to certain activities not pertinent 
here, section 3(18) of the MMPA defines ``harassment'' as any act of 
pursuit, torment, or annoyance, which (i) has the potential to injure a 
marine mammal or marine mammal stock in the wild (Level A harassment); 
or (ii) has the potential to disturb a marine mammal or marine mammal 
stock in the wild by causing disruption of behavioral patterns, 
including, but not limited to, migration, breathing, nursing, breeding, 
feeding, or sheltering (Level B harassment).
    Authorized takes would be by Level B harassment, as use of the 
acoustic source (i.e., impact pile driving) has the potential to result 
in disruption of behavioral patterns for individual marine mammals. 
There is also some potential for auditory injury (Level A harassment) 
to result for gray whales and harbor seals because predicted auditory 
injury zones are larger. 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). NMFS relied on local 
occurrence data and group size to estimate take. 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 [mu]Pa (rms) for continuous (e.g., 
vibratory pile-driving) 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.
    The Coast Guard's proposed activity includes the use of impulsive 
(impact pile-driving) sources, and therefore the

[[Page 66949]]

160 dB re 1 [mu]Pa (rms) threshold is applicable.
    Level A harassment for non-explosive sources--NMFS' Technical 
Guidance for Assessing the Effects of Anthropogenic Sound on Marine 
Mammal Hearing (Version 2.0) (Technical Guidance, 2018) identifies dual 
criteria to assess auditory injury (Level A harassment) to five 
different marine mammal groups (based on hearing sensitivity) as a 
result of exposure to noise from two different types of sources 
(impulsive or non-impulsive). The Coast Guard'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.

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.
    The sound field in the project area is the existing background 
noise plus additional construction noise from the proposed project. 
Marine mammals are expected to be affected via sound generated by the 
primary components of the project (i.e., impact pile driving).
    An impact hammer would be used to place the pile at its intended 
depth through rock or harder substrates. An impact hammer is a steel 
device that works like a piston, producing a series of independent 
strikes to drive the pile. Impact hammering typically generates the 
loudest noise associated with pile installation. The actual durations 
of each installation method vary depending on the type and size of the 
pile.
    In order to calculate distances to the Level A harassment and Level 
B harassment sound thresholds for piles of various sizes being used in 
this project, NMFS used acoustic monitoring data from other locations 
to develop source levels for the various pile sizes and methods (see 
Table 4). Data are provided for 16 and 30-inch concrete piles that are 
the extremes of the possible range of sizes. As noted above, the Coast 
Guard will use a bubble curtain to reduce sounds from pile driving. A 
5dB reduction is applied to the source levels for calculating distances 
to the Level A harassment and Level B harassment sound thresholds. This 
is a conservative reduction based on several studies including CALTRANS 
(2015) and Austin et al. (2016).

                                                          Table 4--Project Sound Source Levels
--------------------------------------------------------------------------------------------------------------------------------------------------------
                         Pile driving activity                             Estimated sound source level at 10 meters
-----------------------------------------------------------------------               without attenuation
                                                                       ------------------------------------------------            Data source
               Hammer type                          Pile type               dB RMS          dB SEL          dB peak
--------------------------------------------------------------------------------------------------------------------------------------------------------
Impact...................................  16-inch concrete...........             166             155             185  CALTRANS (2015) (Table I.2-1,18-
                                                                                                                         inch concrete).
Impact...................................  30-inch concrete...........             176             166             200  CALTRANS (2015) (Table I.2-3).
--------------------------------------------------------------------------------------------------------------------------------------------------------
Note: RMS = root mean square, SEL = single strike sound exposure level; dB peak = peak sound level. A 5-db reduction for use of a bubble curtain reduces
  these source levels when calculating isopleth distances below.

Level B Harassment Zones

    Transmission loss (TL) is the decrease in acoustic intensity as an 
acoustic pressure wave propagates out from a source. TL parameters vary 
with frequency, temperature, sea conditions, current, source and 
receiver depth, water depth, water chemistry, and bottom composition 
and topography. The general formula for underwater TL is:
TL = B * Log10 (R1/R2), where

TL = transmission loss in dB
B = transmission loss coefficient; for practical spreading equals 15
R1 = the distance of the modeled SPL from the driven pile, and
R2 = the distance from the driven pile of the initial measurement


[[Page 66950]]


    The recommended TL coefficient for most nearshore environments is 
the practical spreading value of 15. This value results in an expected 
propagation environment that would lie between spherical and 
cylindrical spreading loss conditions, which is the most appropriate 
assumption for the Coast Guard's proposed activity.
    Using the practical spreading model, the Coast Guard determined 
underwater noise would fall below the behavioral effects threshold for 
marine mammals at distances no greater than 55 m with an effective 
source level of 171 dB rms for the 30-inch piles (Table 5). This 
distance determines the maximum Level B harassment zone for the 
project.

 Table 5--Calculated Distances (Meters) to Level B Harassment Isopleths
                         (m) for Each Pile Type
------------------------------------------------------------------------
                                                              Level B
                        Pile type                          isopleth (m)
------------------------------------------------------------------------
16-inch concrete........................................              12
30-inch concrete........................................              55
------------------------------------------------------------------------

Level A Harassment Zones

    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 take by Level A harassment. 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 
impact pile driving, NMFS User Spreadsheet predicts the closest 
distance at which, if a marine mammal remained at that distance the 
whole duration of the activity, it would not incur PTS.
    Inputs used in the User Spreadsheet (Table 6), and the resulting 
isopleths are reported below (Table 7) for each of the pile types.

             Table 6--NMFS Technical Guidance User Spreadsheet Input To Calculate Level A Isopleths
----------------------------------------------------------------------------------------------------------------
                                                                                                   Days of pile
                   Pile type                       Piles/day           Strikes per pile *           driving **
----------------------------------------------------------------------------------------------------------------
16-inch concrete..............................               6  1564 strikes....................              17
30-inch concrete..............................               6  1748 strikes....................        21 or 30
----------------------------------------------------------------------------------------------------------------
Note: Propagation loss coefficient is 15LogR and Weighting Factor Adjustment is 2 for all cells.
* Strikes per pile are an estimate from a geotechnical report for the project (TCG, 2019).
** Days depends on size of pile ultimately used for wharf support. Take will be calculated using largest zones
  (30 inch piles) and longest duration (38 days using 16 inch support piles and 30-inch fender and corner
  piles).

    The above input scenarios lead to PTS isopleth distances (Level A 
thresholds) of 1 to 194.6 meters (3 to 639 feet), depending on the 
marine mammal group and scenario (Table 7). Note that the Level A 
harassment isopleths are larger than the level B harassment isopleths 
for the low-frequency and high-frequency cetaceans and the phocid 
pinnipeds because of the large number of piles and strikes per day and 
use of only an impact hammer.

 Table 7--Calculated Distances (Meters) to Level A Harassment Isopleths (m) for Each Hearing Group and Pile Type
----------------------------------------------------------------------------------------------------------------
                                                                       High-
                                   Low-frequency   Mid-frequency     frequency        Phocid          Otariid
            Pile type                cetaceans       cetaceans       cetaceans       pinnipeds       pinnipeds
                                     (meters)        (meters)        (meters)        (meters)        (meters)
----------------------------------------------------------------------------------------------------------------
16-inch concrete................            28.0               1            33.4              15             1.1
30-inch concrete................           163.4             5.8           194.6            87.4             6.4
----------------------------------------------------------------------------------------------------------------
Note: a 10-meter shutdown zone will be implemented for all species and activity types to prevent direct injury
  of marine mammals.

Marine Mammal Occurrence and Take Calculation and Estimation

    In this section we provide the information about the presence, 
abundance, or group dynamics of marine mammals that will inform the 
take calculations. Density data in the port and harbor does not exist 
for any species, but as described above, there are three baseline 
biological surveys since 2000 (MEC, 2002; SAIC, 2010; MBC, 2016) that 
provide observations in over 30 defined zones within the harbor, 4 of 
which are near the ensonified area of the project and are used to 
estimate take.
    Here we describe how the information provided above is brought 
together to produce a quantitative take estimate. Take by Level A and 
Level B harassment is proposed for authorization and summarized in 
Table 8.

Gray Whale

    Because live gray whales were not sighted during the baseline 
surveys (see above), but are periodically known from the harbor, and 
the Level A harassment and shutdown zone radius is 200 m (656 feet), we 
propose to authorize two Level A harassment takes (Table 8) for 
inadvertent takes of animals that could enter the shutdown zone 
undetected or before shutdown could be implemented. Because the Level A 
harassment and shutdown zones are larger than the Level B harassment 
zone, we do not propose to authorize take by Level B harassment, but 
recognize animals

[[Page 66951]]

could also inadvertently enter the smaller Level B harassment zone 
after already being recorded as Level A harassment within the larger 
Level A harassment zone.

Bottlenose Dolphin

    The highest observation on any given day in the four zones 
surrounding the Coast Guard Base from the three biological baseline 
surveys (MEC, 2002; SAIC, 2010; MBC, 2016) is 12. Given the small zone 
size relative to the study area an expected number of three animals in 
the project area per day is a reasonable representation of daily 
occurrence for the species. Given a maximum pile driving period of 38 
days, 3 animals per day would equate a take of 114 incidents of Level B 
harassment. Based on the above, we conservatively propose to authorize 
114 Level B harassment takes of bottlenose dolphins (Table 8). Because 
the Level A harassment and shutdown zones are very small and we believe 
the protected species observer (PSO) will be able to effectively 
monitor and implement the shutdown zones, we do not anticipate or 
propose to authorize take by Level A harassment.

Short-Beaked Common Dolphin

    Observations during biological surveys in 2013 through 2014 
included one pod of 40 individuals in the Los Angeles Main Channel 
where the project occurs (MBC, 2016). This number of individuals is 
highly unlikely to be present in the project area on a daily basis. We 
conservatively assume one pod of 40 could be present each full week. 
Given a maximum pile driving period of 38 days, this would equate to 5 
full weeks or 200 takes through Level B harassment. Based on the above, 
we propose to authorize 200 Level B harassment takes of short-beaked 
common dolphins (Table 8). Because the Level A harassment and shutdown 
zones are very small and we believe the PSO will be able to effectively 
monitor and implement the shutdown zones, we do not anticipate or 
propose to authorize take by Level A harassment.

California Sea Lion

    The highest observation on any given day in the four zones 
surrounding the Coast Guard Base from the three biological baseline 
surveys (MEC, 2002; SAIC, 2010; MBC, 2016) is 65 sea lions. Given the 
small zone size relative to the study area an expected number of 10 
animals in the project area per day is a reasonable representation of 
daily occurrence for the species. Given a maximum pile driving period 
of 38 days, 10 animals per day would equate to 380 incidents of Level B 
harassment. Based on the above, we propose to authorize 380 Level B 
harassment takes of California sea lions (Table 8). Because the Level A 
harassment and shutdown zones are very small and we believe the PSO 
will be able to effectively monitor and implement the shutdown zones, 
we do not anticipate or propose to authorize take by Level A 
harassment.

Harbor Seal

    The highest observation on any given day in the four zones 
surrounding the Coast Guard Base from the three biological baseline 
surveys (MEC, 2002; SAIC, 2010; MBC, 2016) is 1 seal. The Level A 
harassment zone for this species is 90 m (295 feet), however the Coast 
Guard proposed a smaller shutdown zone to minimize work stoppages. We 
are proposing a shutdown zone of 55 m (180 feet, see Proposed 
Mitigation section below) that coincides with the size of the Level B 
harassment zone for ease of implementation. It is conservatively 
estimated that 0.5 animals per day might enter the shutdown zone or 
Level A harassment zone between 55 and 90 m (180-295 feet). Given a 
maximum pile driving period of 38 days, this would equate to a take of 
19 individuals through Level A harassment (Table 8). Because the Level 
A harassment and shutdown zones are larger than the Level B harassment 
zone, we do not propose to authorize take by Level B harassment, but 
recognize animals could also enter the smaller Level B harassment zone 
after already being recorded within the larger Level A harassment zone.

   Table 8--Proposed Authorized Amount of Taking, by Level A and Level B Harassment, by Species and Stock and
                                            Percent of Take by Stock
----------------------------------------------------------------------------------------------------------------
                                                                          Authorized take
                             Species                             --------------------------------   Percent of
                                                                      Level B         Level A          stock
----------------------------------------------------------------------------------------------------------------
Harbor seal (Phoca vitulina) California Stock...................               0              19            <0.1
California sea lion (Zalophus californianus) U.S. Stock.........             380               0             0.2
Gray whale (Eschrichtius robustus) Eastern North Pacific Stock..               0               2            <0.1
Common bottlenose dolphin (Tursiops truncatus) California                    114               0            25.2
 Coastal Stock..................................................
Short-beaked common dolphin (Delphinus delphis) California/                  200               0            <0.1
 Oregon/Washington Stock........................................
----------------------------------------------------------------------------------------------------------------

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 (latter not applicable for this action). NMFS 
regulations require applicants for incidental take authorizations to 
include information about the availability and feasibility (economic 
and technological) of equipment, methods, and manner of conducting the 
activity or other means of effecting the least practicable adverse 
impact upon the affected species or stocks and their habitat (50 CFR 
216.104(a)(11)).
    In evaluating how mitigation may or may not be appropriate to 
ensure the least practicable adverse impact on species or stocks and 
their habitat, as well as subsistence uses where applicable, we 
carefully consider two primary factors:
    (1) The manner in which, and the degree to which, the successful 
implementation of the measure(s) is expected to reduce impacts to 
marine mammals, marine mammal species or stocks, and their habitat. 
This considers the nature of the potential adverse impact being 
mitigated (likelihood, scope, range). It further considers the 
likelihood that the measure will be effective if implemented 
(probability of accomplishing the mitigating result if implemented as 
planned), the likelihood of effective implementation (probability 
implemented as planned); and
    (2) The practicability of the measures for applicant 
implementation, which may consider such things as cost, impact on 
operations, and, in the case of a military readiness activity,

[[Page 66952]]

personnel safety, practicality of implementation, and impact on the 
effectiveness of the military readiness activity.
    The following mitigation measures are proposed in the IHA:
     For in-water heavy machinery work other than pile driving, 
if a marine mammal comes within 10 m, operations shall cease and 
vessels shall reduce speed to the minimum level required to maintain 
steerage and safe working conditions. This type of work could include 
the following activities: (1) Movement of the barge to the pile 
location; or (2) positioning of the pile on the substrate via a crane 
(i.e., stabbing the pile);
     Conduct briefings between construction supervisors and 
crews and the marine mammal monitoring team prior to the start of all 
pile driving activity and when new personnel join the work, to explain 
responsibilities, communication procedures, marine mammal monitoring 
protocol, and operational procedures;
     For those marine mammals for which Level B harassment take 
has not been requested, in-water pile installation/removal will shut 
down immediately if such species are observed within or entering the 
Level B harassment zone; and
     If take reaches the authorized limit for an authorized 
species, pile installation will be stopped as these species approach 
the Level B harassment zone to avoid additional take.
    The following mitigation measures would apply to the Coast Guard's 
in-water construction activities.
     Establishment of Shutdown Zones--The Coast Guard will 
establish shutdown zones for all pile driving activities. The purpose 
of a shutdown zone is generally to define an area within which shutdown 
of the activity would occur upon sighting of a marine mammal (or in 
anticipation of an animal entering the defined area). Shutdown zones 
will vary based on the activity type and marine mammal hearing group 
(Table 9). Shutdown zones are rounded up to the next 10 m from the 
largest Level A harassment zones in Table 7, except in the case of the 
phocid group where the shutdown zone is reduced to the same size as the 
largest Level B harassment zone (55 m) and the applicant has requested 
the authorization of Level A harassment takes for the area within the 
Level A harassment one and outside the shutdown zone.
     The placement of PSOs during all pile driving and removal 
activities (described in detail in the Proposed Monitoring and 
Reporting section) will ensure that the entire shutdown zone is visible 
during pile installation. Should environmental conditions deteriorate 
such that marine mammals within the entire shutdown zone would not be 
visible (e.g., fog, heavy rain), pile driving and removal must be 
delayed until the PSO is confident marine mammals within the shutdown 
zone could be detected.

                                             Table 9--Shutdown Zones
----------------------------------------------------------------------------------------------------------------
                                                                       High-
                                   Low-frequency   Mid-frequency     frequency        Phocid          Otariid
            Pile type                cetaceans       cetaceans       cetaceans       pinnipeds       pinnipeds
                                     (meters)        (meters)        (meters)        (meters)        (meters)
----------------------------------------------------------------------------------------------------------------
16-inch concrete................              30              10              40              20              10
30-inch concrete................             170              10             200              55              10
----------------------------------------------------------------------------------------------------------------

     Monitoring for Level A and B Harassment--The Coast Guard 
will monitor the Level A and B harassment zones. Monitoring zones 
provide utility for observing by establishing monitoring protocols for 
areas adjacent to the shutdown zones. Monitoring zones enable observers 
to be aware of and communicate the presence of marine mammals in the 
project area outside the shutdown zone and thus prepare for a potential 
halt of activity should the animal enter the shutdown zone. Placement 
of PSOs will allow PSOs to observe marine mammals within the Level B 
harassment zones.
     Pre-activity Monitoring--Prior to the start of daily in-
water construction activity, or whenever a break in pile driving/
removal of 30 minutes or longer occurs, PSOs will observe the shutdown 
and monitoring zones for a period of 30 minutes. The shutdown zone will 
be considered cleared when a marine mammal has not been observed within 
the zone for that 30-minute period. If a marine mammal is observed 
within the shutdown zone, a soft-start cannot proceed until the animal 
has left the zone or has not been observed for 15 minutes. When a 
marine mammal for which Level B harassment take is authorized is 
present in the Level B harassment zone, activities may begin and Level 
B harassment take will be recorded. If the entire Level B harassment 
zone is not visible at the start of construction, pile driving 
activities can begin. If work ceases for more than 30 minutes, the pre-
activity monitoring of the shutdown zones will be required.
     Soft Start--Soft-start procedures are believed to provide 
additional protection to marine mammals by providing warning and/or 
giving marine mammals a chance to leave the area prior to the hammer 
operating at full capacity. For impact pile driving, contractors will 
be required to provide an initial set of three strikes from the hammer 
at reduced energy, followed by a thirty-second waiting period. This 
procedure will be conducted three times before impact pile driving 
begins. Soft start will be implemented at the start of each day's 
impact pile driving and at any time following cessation of impact pile 
driving for a period of thirty minutes or longer.
     Bubble Curtain--The Coast Guard is required to employ a 
bubble curtain during all impact pile driving and operate it in a 
manner consistent with the following performance standards: (1) The 
bubble curtain must distribute air bubbles around 100 percent of the 
piling perimeter for the full depth of the water column; (2) The lowest 
bubble ring must be in contact with the mudline for the full 
circumference of the ring, and the weights attached to the bottom ring 
shall ensure 100 percent mudline contact. No parts of the ring or other 
objects shall prevent full mudline contact; and (3) Air flow to the 
bubblers must be balanced around the circumference of the pile.
     Hydroacoustic monitoring--The Coast Guard is required to 
conduct hydroacoustic monitoring of at least two piles of each pile 
diameter.
     Pile driving or removal is planned to occur during 
daylight hours.
    Based on our evaluation of the applicant's proposed measures, as 
well as other measures considered by NMFS, NMFS has preliminarily 
determined that the proposed mitigation measures provide the means 
effecting the least

[[Page 66953]]

practicable impact on the affected species or stocks and their habitat, 
paying particular attention to rookeries, mating grounds, and areas of 
similar significance.

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

    Marine mammal monitoring must be conducted in accordance with the 
Monitoring section of the application and Section 5 of the IHA. Marine 
mammal monitoring during pile driving must be conducted by NMFS-
approved PSOs in a manner consistent with the following:
     Independent PSOs (i.e., not construction personnel) who 
have no other assigned tasks during monitoring periods must be used;
     At least one PSO must have prior experience performing the 
duties of a PSO during construction activity pursuant to a NMFS-issued 
incidental take authorization.
     Other PSOs may substitute education (degree in biological 
science or related field) or training for experience; and
     The Coast Guard must submit PSO Curriculum Vitae for 
approval by NMFS prior to the onset of pile driving.
    PSOs must have the following additional qualifications:
     Ability to conduct field observations and collect data 
according to assigned protocols;
     Experience or training in the field identification of 
marine mammals, including the identification of behaviors;
     Sufficient training, orientation, or experience with the 
construction operation to provide for personal safety during 
observations;
     Writing skills sufficient to 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, times, and reason for implementation 
of mitigation (or why mitigation was not implemented when required); 
and marine mammal behavior; and
     Ability to communicate orally, by radio or in person, with 
project personnel to provide real-time information on marine mammals 
observed in the area as necessary.
    One PSO will be employed. PSO location will provide an unobstructed 
view of all water within the shutdown and Level A and Level B 
harassment zones.
    Monitoring will be conducted 30 minutes before, during, and 30 
minutes after pile driving/removal 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 driven or removed. Pile driving 
activities include the time to install or remove a single pile or 
series of piles, as long as the time elapsed between uses of the pile 
driving or drilling equipment is no more than 30 minutes.

Reporting

    A draft marine mammal monitoring report will be submitted to NMFS 
within 90 days after the completion of pile driving and removal 
activities, or 60 days prior to a requested date of issuance of any 
future IHAs for projects at the same location, whichever comes first. 
The report will include an overall description of work completed, a 
narrative regarding marine mammal sightings, and associated PSO 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).
     Environmental conditions during monitoring periods (at 
beginning and end of PSO shift and whenever conditions change 
significantly), including Beaufort sea state and any other relevant 
weather conditions including cloud cover, fog, sun glare, and overall 
visibility to the horizon, and estimated observable distance (if less 
than the harassment zone distance).
     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 
observation, including direction of travel and estimated time spent 
within the Level A and Level B harassment zones while the source was 
active.
     Number of marine mammals detected within the harassment 
zones, by species.
     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

[[Page 66954]]

number of incidences of take, such as ability to track groups or 
individuals.
     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.
    Hydroacoustic Monitoring and Reporting--The Coast Guard will 
monitor the driving of at least two piles of each diameter. As part of 
the above-mentioned report, or in a separate report with the same 
timelines as above, the Coast Guard will provide an acoustic monitoring 
report for this work. The acoustic monitoring report must, at minimum, 
include the following:
     Hydrophone equipment and methods: Recording device, 
sampling rate, distance (m) from the pile where recordings were made; 
depth of recording device(s).
     Type of pile being driven, substrate type, method of 
driving during recordings, and if a sound attenuation device is used.
     For impact pile driving: Pulse duration and mean, median, 
and maximum sound levels (dB re: 1[micro]Pa): SELcum, peak sound 
pressure level (SPLpeak), and single-strike sound exposure level (SELs-
s).
     Number of strikes per pile measured, one-third octave band 
spectrum and power spectral density plot.

Reporting Injured or Dead Marine Mammals

    In the event that personnel involved in the construction activities 
discover an injured or dead marine mammal, the Coast Guard shall report 
the incident to the Office of Protected Resources (OPR), NMFS and to 
the regional stranding coordinator as soon as feasible. If the death or 
injury was clearly caused by the specified activity, the Coast Guard 
must immediately cease the specified activities until NMFS is able to 
review the circumstances of the incident and determine what, if any, 
additional measures are appropriate to ensure compliance with the terms 
of the IHA. The IHA-holder must not resume their activities until 
notified by NMFS. The report must include the following information:
     Time, date, and location (latitude/longitude) of the first 
discovery (and updated location information if known and applicable);
     Species identification (if known) or description of the 
animal(s) involved;
     Condition of the animal(s) (including carcass condition if 
the animal is dead);
     Observed behaviors of the animal(s), if alive;
     If available, photographs or video footage of the 
animal(s); and
     General circumstances under which the animal was 
discovered.

Negligible Impact Analysis and Determination

    NMFS has defined negligible impact as an impact resulting from the 
specified activity that cannot be reasonably expected to, and is not 
reasonably likely to, adversely affect the species or stock through 
effects on annual rates of recruitment or survival (50 CFR 216.103). A 
negligible impact finding is based on the lack of likely adverse 
effects on annual rates of recruitment or survival (i.e., population-
level effects). An estimate of the number of takes alone is not enough 
information on which to base an impact determination. In addition to 
considering estimates of the number of marine mammals that might be 
``taken'' through harassment, NMFS considers other factors, such as the 
likely nature of any responses (e.g., intensity, duration), the context 
of any responses (e.g., critical reproductive time or location, 
migration), as well as effects on habitat, and the likely effectiveness 
of the mitigation. We also assess the number, intensity, and context of 
estimated takes by evaluating this information relative to population 
status. Consistent with the 1989 preamble for NMFS's implementing 
regulations (54 FR 40338; September 29, 1989), the impacts from other 
past and ongoing anthropogenic activities are incorporated into this 
analysis via their impacts on the environmental baseline (e.g., as 
reflected in the regulatory status of the species, population size and 
growth rate where known, ongoing sources of human-caused mortality, or 
ambient noise levels).
    To avoid repetition, this introductory discussion of our analyses 
applies to all of the species listed in Table 8, given that many of the 
anticipated effects of this project on different marine mammal stocks 
are expected to be relatively similar in nature. Pile driving 
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. Potential takes could occur if individuals 
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. The potential for 
harassment is minimized through the construction method and the 
implementation of the planned mitigation measures (see Proposed 
Mitigation section).
    The Level A harassment zones identified in Table 7 are based upon 
an animal exposed to impact pile driving multiple piles per day. 
Considering duration of impact driving each pile (up to 45 minutes) and 
breaks between pile installations (to reset equipment and move pile 
into place), this means an animal would have to remain within the area 
estimated to be ensonified above the Level A harassment threshold for 
multiple hours. This is highly unlikely given marine mammal movement 
throughout the area. So while the take we are proposing to authorize is 
expected to occur, if an animal was exposed to accumulated sound 
energy, the resulting PTS would likely be small (e.g., PTS onset) at 
lower frequencies where pile driving energy is concentrated, and 
unlikely to result in impacts to individual fitness, reproduction, or 
survival.
    The nature of the pile driving project precludes the likelihood of 
serious injury or mortality. For all species and stocks, take would 
occur within a limited, confined area (Los Angeles port) of any given 
stock's range. Level A and Level B harassment will be reduced to the 
level of least practicable adverse impact through use of mitigation 
measures described herein. Further the amount of take proposed to be 
authorized for any given stock is small when compared to stock 
abundance.
    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; see Behavioral Harassment section above) 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 and removal would occur across a few weeks, 
any harassment would be temporary. There are no other areas or times of 
known biological

[[Page 66955]]

importance for any of the affected species.
    In addition, 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.
     No biologically important areas have been identified 
within the project area.
     For all species, the project area is a very small, human-
altered and peripheral part of their range.
     The Coast Guard would implement mitigation measures such 
soft-starts, bubble curtain, and shut downs.
     Monitoring reports from similar work in the ports 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. When the predicted number of individuals to 
be taken is fewer than one third of the species or stock abundance, the 
take is considered to be of small numbers. 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 of all species or 
stocks is below one third of the estimated stock abundance. These are 
all likely conservative estimates of individuals taken because they 
assume all takes are of different individual animals which is likely 
not the case. Some individuals may return multiple times in a day, but 
PSOs would count them as separate takes if they cannot be individually 
identified.
    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

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

Endangered Species Act (ESA)

    Section 7(a)(2) of the Endangered Species Act of 1973 (ESA: 16 
U.S.C. 1531 et seq.) requires that each Federal agency insure that any 
action it authorizes, funds, or carries out is not likely to jeopardize 
the continued existence of any endangered or threatened species or 
result in the destruction or adverse modification of designated 
critical habitat.
    No incidental take of ESA-listed species is proposed for 
authorization or expected to result from this activity. Therefore, NMFS 
has determined that formal consultation under section 7 of the ESA is 
not required for this action.

Proposed Authorization

    As a result of these preliminary determinations, NMFS proposes to 
issue an IHA to the Coast Guard to conduct the Base Los Angeles/Long 
Beak Wharf Expansion project in California February 1, 2021 through 
January 31, 2022, 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 Base 
Los Angeles/Long Beak Wharf Expansion 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-time, 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 Description of 
Proposed Activity section of this notice is planned or (2) the 
activities as described in the Description of Proposed 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); 
and
    (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; and
     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

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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: October 16, 2020.
Donna S. Wieting,
Director, Office of Protected Resources, National Marine Fisheries 
Service.
[FR Doc. 2020-23304 Filed 10-20-20; 8:45 am]
BILLING CODE 3510-22-P