[Federal Register Volume 80, Number 142 (Friday, July 24, 2015)]
[Notices]
[Pages 44033-44057]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2015-18145]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

RIN 0648-XE055


Takes of Marine Mammals Incidental to Specified Activities; 
Taking Marine Mammals Incidental to Two Pier Maintenance Projects

AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and 
Atmospheric Administration (NOAA), Commerce.

ACTION: Notice; two proposed incidental harassment authorizations; 
request for comments.

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SUMMARY: NMFS has received two requests from the U.S. Navy (Navy) for 
authorization to take marine mammals incidental to construction 
activities as part of two separate pier maintenance projects at Naval 
Base Kitsap Bremerton. Pursuant to the Marine Mammal Protection Act 
(MMPA), NMFS is requesting comments on its proposal to issue incidental 
harassment authorizations (IHA) to the Navy to incidentally take marine 
mammals, by Level B Harassment only, during the specified activity.

DATES: Comments and information must be received no later than August 
24, 2015.

ADDRESSES: Comments on the applications should be addressed to Jolie 
Harrison, Chief, Permits and Conservation Division, Office of Protected 
Resources, National Marine Fisheries Service. Physical comments should 
be sent to 1315 East-West Highway, Silver Spring, MD 20910 and 
electronic comments should be sent to [email protected].
    Instructions: NMFS is not responsible for comments sent by any 
other method, to any other address or individual, or received after the 
end of the comment period. 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 to the Internet at 
www.nmfs.noaa.gov/pr/permits/incidental/construction.htm 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: Ben Laws, Office of Protected 
Resources, NMFS, (301) 427-8401.

SUPPLEMENTARY INFORMATION: 

Availability

    An electronic copy of the Navy's application and supporting 
documents, as well as a list of the references cited in this document, 
may be obtained by visiting the Internet at: www.nmfs.noaa.gov/pr/permits/incidental/construction.htm. In case of problems accessing 
these documents, please call the contact listed above.

National Environmental Policy Act (NEPA)

Pier 6 Maintenance Project

    The Navy prepared an Environmental Assessment (EA; 2013) for this 
project. We subsequently adopted the EA and signed our own Finding of 
No Significant Impact (FONSI) prior to issuing the first IHA for this 
project, in accordance with NEPA and the regulations published by the 
Council on Environmental Quality. Information in the Navy's 
application, the Navy's EA, and this notice collectively provide the 
environmental information related to proposed issuance of this IHA for 
public review and comment. All documents are available at the 
aforementioned Web site. We will review all comments submitted in 
response to this notice as we complete the NEPA process, including a 
decision of whether to reaffirm the existing FONSI, prior to a final 
decision on the incidental take authorization request.

Pier 4 Maintenance Project

    The Navy prepared an EA to consider the direct, indirect and 
cumulative effects to the human environment resulting from the 
maintenance project. NMFS has reviewed the EA and believes it 
appropriate to adopt the EA in order to assess the impacts to the human 
environment of issuance of an IHA to the Navy and subsequently sign our 
own FONSI. Information in the Navy's application, the Navy's EA, and 
this notice collectively provide the environmental information related 
to proposed issuance of this IHA for public review and comment.
    For both proposed IHAs, all documents are available at the 
aforementioned Web site. We will review all comments submitted in 
response to this notice as we complete the NEPA processes, including a 
final decision of whether to reaffirm the existing FONSI or adopt the 
Navy's EA and sign a FONSI (for the Pier 6 and Pier 4 IHAs, 
respectively), prior to a final decision on the incidental take 
authorization requests.

Background

    Sections 101(a)(5)(A) and (D) of the MMPA (16 U.S.C. 1361 et seq.) 
direct the Secretary of Commerce to allow, upon request by U.S. 
citizens who engage in a specified activity (other than commercial 
fishing) within a specified area, the incidental, but not intentional, 
taking of small numbers of marine mammals, providing that certain 
findings are made and the necessary prescriptions are established.
    The incidental taking of small numbers of marine mammals may be 
allowed only if NMFS (through authority delegated by the Secretary) 
finds that the total taking by the specified activity during the 
specified time period will (i) have a negligible impact on the species 
or stock(s) and (ii) not have an unmitigable adverse impact on the 
availability of the species or stock(s) for subsistence uses (where 
relevant). Further, the permissible methods of taking and requirements 
pertaining to the mitigation, monitoring and reporting of such taking 
must be set forth, either in specific regulations or in an 
authorization.
    The allowance of such incidental taking under section 101(a)(5)(A), 
by harassment, serious injury, death, or a combination thereof, 
requires that regulations be established. Subsequently, a Letter of 
Authorization may be issued pursuant to the prescriptions established 
in such regulations, providing that the level of taking will be 
consistent with the findings made for the total taking allowable under 
the specific regulations. Under section 101(a)(5)(D), NMFS may 
authorize such incidental taking by harassment only, for periods of not 
more

[[Page 44034]]

than one year, pursuant to requirements and conditions contained within 
an IHA. The establishment of prescriptions through either specific 
regulations or an authorization requires notice and opportunity for 
public comment.
    NMFS has defined ``negligible impact'' in 50 CFR 216.103 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.'' 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].''

Summary of Requests

    On April 14, 2015, we received two requests from the Navy for 
authorization to take marine mammals incidental to pile driving and 
removal associated with the Pier 6 and Pier 4 maintenance projects at 
Naval Base Kitsap Bremerton, WA (NBKB). Hereafter, it may be assumed 
that use of the generic term ``pile driving'' refers to both pile 
driving and removal unless referring specifically to pile installation. 
The Navy submitted revised versions of the requests on May 20 and June 
12, 2015, the latter of which we deemed adequate and complete. This is 
expected to be the third and final year of in-water work associated 
with the Pier 6 project. The Pier 4 project is expected to require only 
one year to complete in-water work. Each section of this notice is 
either separated into project-specific subsections or indicates whether 
the discussion to follow applies to both projects or applies to both 
projects except where indicated.
    The use of both vibratory and impact pile driving is expected to 
produce underwater sound at levels that have the potential to result in 
behavioral harassment of marine mammals. Species with the expected 
potential to be present during all or a portion of the in-water work 
windows include the Steller sea lion (Eumetopias jubatus monteriensis), 
California sea lion (Zalophus californianus), and harbor seal (Phoca 
vitulina richardii). All of these species may be present during the 
proposed periods of validity for these IHAs.
    For Pier 6, this would be the third such IHA, if issued, following 
the IHAs issued effective from December 1, 2013, through March 1, 2014 
(78 FR 69825) and from October 1, 2014, through March 1, 2015 (79 FR 
59238). Monitoring reports associated with these previous IHAs are 
available on the Internet at www.nmfs.noaa.gov/pr/permits/incidental/construction.htm and provide environmental information related to 
proposed issuance of these IHAs for public review and comment.

Description of the Specified Activities

    In this section, we provide a mixed discussion with project-
specific portions indicated.

Overview

    NBKB serves as the homeport for a nuclear aircraft carrier and 
other Navy vessels and as a shipyard capable of overhauling and 
repairing all types and sizes of ships. Other significant capabilities 
include alteration, construction, deactivation, and dry-docking of 
naval vessels. Both Pier 6 and Pier 4, originally constructed in 1926 
and 1922, respectively, require substantial maintenance to maintain 
readiness. Over the course of the entire Pier 6 project, the Navy will 
remove 400 deteriorating creosoted timber (380) and steel (20) fender 
piles and replace them with 330 new pre-stressed concrete fender piles. 
For Pier 4, the Navy plans to remove eighty deteriorating creosoted 
timber fender piles and replace them with eighty new steel fender 
piles.

Dates and Duration

    For both projects, in-water work would occur only during approved 
work windows established to protect bull trout and migrating salmon; 
however, the two projects would operate under different requirements 
pursuant to separate agreements with the U.S. Fish and Wildlife Service 
(FWS). Under a 2013 agreement with FWS, in-water work associated with 
the Pier 6 project may be conducted from June 15 to March 1 of any 
year. In 2015, FWS requested that Navy operate under a more restrictive 
work window related to bull trout (Salvelinus confluentus) occurrence 
in the project area, and in-water work associated with the Pier 4 
project may occur from July 16 to February 15.
    Pier 6--The total three-year project is expected (on the basis of 
assumed production rates) to require fifty days of vibratory pile 
removal and 135 days of impact pile driving (total of 185 days of in-
water pile driving work), although it appears that better-than-expected 
production rates will result in a reduced number of total days. Under 
the proposed action--which includes only the portion of the project 
that would be completed under this proposed IHA--a maximum of sixty 
pile driving days would occur. The Navy proposes to conduct fifteen 
days of vibratory pile removal and 45 days of pile installation with an 
impact hammer. Either type of pile driving may occur on any day during 
the proposed period of validity. The proposed Pier 6 IHA covers only 
the third year (in-water work window) of the project, and would be 
valid from September 1, 2015, through March 1, 2016.
    Pier 4--The Navy expects to require thirty days of total work, 
including approximately ten days of vibratory pile removal and twenty 
days of vibratory pile driving. Either type of pile driving may occur 
on any day during the proposed period of validity (within approved work 
window). The proposed Pier 4 IHA would be valid for one year, from 
December 1, 2015, through November 30, 2016. The Navy requested a one-
year period of validity for this proposed IHA due to uncertainty 
regarding the project start date. However, the proposed in-water work 
would occur within only a single work window; i.e., would occur from 
December 1, 2015, through February 15, 2016, or would occur from July 
16, 2016, through November 30, 2016.

Specific Geographic Region

    NBKB is located on the north side of Sinclair Inlet in Puget Sound 
(see Figures 1-1 and 2-1 of the Navy's applications). Sinclair Inlet, 
an estuary of Puget Sound extending 3.5 miles southwesterly from its 
connection with the Port Washington Narrows, connects to the main basin 
of Puget Sound through Port Washington Narrows and then Agate Pass to 
the north or Rich Passage to the east. Sinclair Inlet has been 
significantly modified by development activities. Fill associated with 
transportation, commercial, and residential development of NBKB, the 
City of Bremerton, and the local ports of Bremerton and Port Orchard 
has resulted in significant changes to the shoreline. The area 
surrounding both Pier 6 and Pier 4 is industrialized, armored and 
adjacent to railroads and highways. Sinclair Inlet is also the 
receiving body for a wastewater treatment plant located just west of 
NBKB. Sinclair Inlet is relatively shallow and does not flush fully 
despite freshwater stream inputs. The action area is essentially the 
same for both projects, and is referred to generally as

[[Page 44035]]

the project area hereafter. Pier 4 and Pier 6 are co-located 
approximately 300 m apart on the NBKB waterfront. Please see Figure 4-1 
of the Navy's applications.

Detailed Description of Activities

    Pier 6--The Navy plans to remove deteriorated timber and steel 
fender piles at Pier 6 and replace them with prestressed concrete 
piles. The entire project calls for the removal of 380 12-in diameter 
creosoted timber piles and twenty 12-in steel pipe piles. These would 
be replaced with 240 18-in square concrete piles and ninety 24-in 
square concrete piles. It is not possible to specify accurately the 
number of piles that might be installed or removed in any given work 
window, due to various delays that may be expected during construction 
work and uncertainty inherent to estimating production rates. The Navy 
assumes a notional production rate of sixteen piles per day (removal) 
and four piles per day (installation) in determining the number of days 
of pile driving expected, and scheduling (as well as exposure analysis) 
is based on this assumption.
    All piles are planned for removal via vibratory driver. The driver 
is suspended from a barge-mounted crane and positioned on top of a 
pile. Vibration from the activated driver loosens the pile from the 
substrate. Once the pile is released, the crane raises the driver and 
pulls the pile from the sediment. Vibratory extraction is expected to 
take approximately 5-30 minutes per pile. If piles break during 
removal, the remaining portion may be removed via direct pull or with a 
clamshell bucket. Replacement piles would be installed via impact 
driver and would require approximately 15-60 minutes of driving time 
per pile, depending on subsurface conditions. Impact driving or 
vibratory removal could occur on any work day during the period of the 
proposed IHA.
    Description of Work Accomplished, Pier 6--During the first in-water 
work season for the Pier 6 project, the contractor completed 
installation of two concrete piles, on two separate days. During the 
second in-water work season, 282 piles were removed by vibratory 
extraction or direct pull. The contractor found that the direct pull 
method was very effective in pile removal and approximately fifty 
percent of the piles that were removed during Year 2, including three 
steel piles, were pulled without the use of the vibratory driver. A 
total of 168 new concrete piles were installed using an impact hammer. 
Therefore, approximately 118 piles remain to be removed and 160 to be 
installed. The Navy's monitoring reports are available on the Internet 
at: www.nmfs.noaa.gov/pr/permits/incidental/construction.htm.
    Pier 4--The Navy plans to remove eighty deteriorated 14-in timber 
fender piles at Pier 4 and replace them with eighty new 12 to 14-in 
steel fender piles. Here, due to slightly different geotechnical 
conditions, the Navy assumes a notional production rate of eight piles 
per day (removal) and four piles per day (installation) in determining 
the number of days of pile driving expected, and scheduling (as well as 
exposure analysis) is based on this assumption. All pile driving and 
removal would be accomplished with a vibratory driver (except where 
removal is accomplished by direct pull or other mechanical means, e.g., 
clamshell, cutting). Expected per-pile time for removal and 
installation is similar to that described for Pier 6.
    Neither project would employ more than one pile driving rig. 
Therefore, there would not be concurrent pile driving specific to 
either project. In addition, due to scheduling differences, it is 
unlikely that in-water work associated with the two projects would 
occur concurrently, meaning that it is highly unlikely that there would 
be more than one pile driving rig in operation at NBKB at any time even 
considering both projects. Pile driving would occur only during 
daylight hours.

Description of Marine Mammals in the Area of the Specified Activity

    There are five marine mammal species with records of occurrence in 
waters of Sinclair Inlet in the action area. These are the California 
sea lion, harbor seal, Steller sea lion, gray whale (Eschrichtius 
robustus), and killer whale (Orcinus orca). The harbor seal is a year-
round resident of Washington inland waters, including Puget Sound, 
while the sea lions are absent for portions of the summer. For the 
killer whale, both transient (west coast stock) and resident (southern 
stock) animals have occurred in the area. However, southern resident 
animals are known to have occurred only once, with the last confirmed 
sighting from 1997 in Dyes Inlet. A group of 19 whales from the L-25 
subpod entered and stayed in Dyes Inlet, which connects to Sinclair 
Inlet northeast of NBKB, for thirty days. Dyes Inlet may be reached 
only by traversing from Sinclair Inlet through the Port Washington 
Narrows, a narrow connecting body that is crossed by two bridges, and 
it was speculated at the time that the whales' long stay was the result 
of a reluctance to traverse back through the Narrows and under the two 
bridges. There is one other unconfirmed report of a single southern 
resident animal occurring in the project area, in January 2009. Of 
these stocks, the southern resident killer whale is listed (as 
endangered) under the Endangered Species Act (ESA).
    An additional seven species have confirmed occurrence in Puget 
Sound, but are considered rare to extralimital in Sinclair Inlet and 
the surrounding waters. These species--the humpback whale (Megaptera 
novaeangliae), minke whale (Balaenoptera acutorostrata scammoni), 
Pacific white-sided dolphin (Lagenorhynchus obliquidens), harbor 
porpoise (Phocoena phocoena vomerina), Dall's porpoise (Phocoenoides 
dalli dalli), and northern elephant seal (Mirounga angustirostris)--
along with the southern resident killer whale, are considered extremely 
unlikely to occur in the action area or to be affected by the specified 
activities, and are not considered further in this document. A review 
of sightings records available from the Orca Network 
(www.orcanetwork.org; accessed July 13, 2015) confirms that there are 
no recorded observations of these species in the action area (with the 
exception of the southern resident sightings described above).
    We have reviewed the Navy's detailed species descriptions, 
including life history information, for accuracy and completeness and 
refer the reader to sections 3 and 4 of the Navy's application instead 
of reprinting the information here. Please also refer to NMFS' Web site 
(www.nmfs.noaa.gov/pr/species/mammals) for generalized species accounts 
and to the Navy's Marine Resource Assessment for the Pacific Northwest, 
which documents and describes the marine resources that occur in Navy 
operating areas of the Pacific Northwest, including Puget Sound (DoN, 
2006). The document is publicly available at www.navfac.navy.mil/products_and_services/ev/products_and_services/marine_resources/marine_resource_assessments.html (accessed July 13, 2015).
    Table 1 lists the marine mammal species with expected potential for 
occurrence in the vicinity of NBKB during the project timeframe and 
summarizes key information regarding stock status and abundance. 
Taxonomically, we follow Committee on Taxonomy (2014). Please see NMFS' 
Stock Assessment Reports (SAR), available at www.nmfs.noaa.gov/pr/sars, 
for more detailed accounts of these stocks' status and abundance. The 
harbor seal, California sea lion, and gray

[[Page 44036]]

whale are assessed in the Pacific SARs (e.g., Carretta et al., 2014), 
while the Steller sea lion and transient killer whale are considered in 
the Alaska SARs (e.g., Allen and Angliss, 2014).
    In the species accounts provided here, we offer a brief 
introduction to the species and relevant stock as well as available 
information regarding population trends and threats, and describe any 
information regarding local occurrence.

                                           Table 1--Marine Mammals Potentially Present in the Vicinity of NBKB
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                                                     ESA/MMPA      Stock abundance
                                                     status;       (CV, Nmin, most                                              Relative occurrence in
           Species                   Stock        Strategic  (Y/   recent abundance         PBR \3\         Annual M/SI \4\    Sinclair Inlet; season of
                                                      N) \1\         survey) \2\                                                      occurrence
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Order Cetartiodactyla--Cetacea--Superfamily Mysticeti (baleen whales)...................................................................................
Family Eschrichtiidae...................................................................................................................................
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Gray whale...................  Eastern North     --; N..........      20,990 (0.05;  624.................           \10\ 132  Rare; year-round.
                                Pacific \5\.                       20,125; 2010-11)
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Superfamily Odontoceti (toothed whales, dolphins, and porpoises)........................................................................................
Family Delphinidae......................................................................................................................................
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Killer whale.................  West coast        --; N..........    243 (n/a; 2009)  2.4.................                  0  Rare; year-round.
                                transient \6\.
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Order Carnivora--Superfamily Pinnipedia.................................................................................................................
Family Otariidae (eared seals and sea lions)............................................................................................................
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California sea lion..........  U.S.............  --; N..........      296,750 (n/a;  9,200...............                389  Common; year-round
                                                                     153,337; 2011)                                            (excluding July).
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Steller sea lion.............  Eastern U.S.\5\.  --; N \8\......  60,131-74,448 (n/  1,645...............               92.3  Occasional/seasonal; Oct-
                                                                   a; 36,551; 2008-                                            May.
                                                                             13)\9\
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Family Phocidae (earless seals).........................................................................................................................
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Harbor seal..................  Washington        --; N..........      11,036 (0.15;  undetermined........               >2.8  Common; year-round.
                                northern inland                        7,213; 1999)
                                waters \7\.
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\1\ ESA status: Endangered (E), Threatened (T)/MMPA status: Depleted (D). A dash (-) indicates that the species is not listed under the ESA or
  designated as depleted under the MMPA. Under the MMPA, a strategic stock is one for which the level of direct human-caused mortality exceeds PBR (see
  footnote 3) or which is determined to be declining and likely to be listed under the ESA within the foreseeable future. Any species or stock listed
  under the ESA is automatically designated under the MMPA as depleted and as a strategic stock.
\2\ CV is coefficient of variation; Nmin is the minimum estimate of stock abundance. In some cases, CV is not applicable. For killer whales, the
  abundance values represent direct counts of individually identifiable animals; therefore there is only a single abundance estimate with no associated
  CV. For certain stocks of pinnipeds, abundance estimates are based upon observations of animals (often pups) ashore multiplied by some correction
  factor derived from knowledge of the species (or similar species) life history to arrive at a best abundance estimate; therefore, there is no
  associated CV. In these cases, the minimum abundance may represent actual counts of all animals ashore. The most recent abundance survey that is
  reflected in the abundance estimate is presented; there may be more recent surveys that have not yet been incorporated into the estimate.
\3\ Potential biological removal, defined by the MMPA as the maximum number of animals, not including natural mortalities, that may be removed from a
  marine mammal stock while allowing that stock to reach or maintain its optimum sustainable population size (OSP).
\4\ These values, found in NMFS' SARs, represent annual levels of human-caused mortality plus serious injury from all sources combined (e.g., commercial
  fisheries, subsistence hunting, ship strike). Annual M/SI often cannot be determined precisely and is in some cases presented as a minimum value. All
  values presented here are from the draft 2014 SARs (www.nmfs.noaa.gov/pr/sars/draft.htm).
\5\ Abundance estimates (and resulting PBR values) for these stocks are new values presented in the draft 2014 SARs. This information was made available
  for public comment and is currently under review and therefore may be revised prior to finalizing the 2014 SARs. However, we consider this information
  to be the best available for use in this document.
\6\ The abundance estimate for this stock includes only animals from the ``inner coast'' population occurring in inside waters of southeastern Alaska,
  British Columbia, and Washington--excluding animals from the ``outer coast'' subpopulation, including animals from California--and therefore should be
  considered a minimum count. For comparison, the previous abundance estimate for this stock, including counts of animals from California that are now
  considered outdated, was 354.
\7\ Abundance estimates for these stocks are greater than eight years old and are therefore not considered current. PBR is considered undetermined for
  these stocks, as there is no current minimum abundance estimate for use in calculation. We nevertheless present the most recent abundance estimates
  and PBR values, as these represent the best available information for use in this document.
\8\ The eastern distinct population segment of the Steller sea lion, previously listed under the ESA as threatened, was delisted on December 4, 2013 (78
  FR 66140; November 4, 2013).
\9\ Best abundance is calculated as the product of pup counts and a factor based on the birth rate, sex and age structure, and growth rate of the
  population. A range is presented because the extrapolation factor varies depending on the vital rate parameter resulting in the growth rate (i.e.,
  high fecundity or low juvenile mortality).
\10\ Includes annual Russian subsistence harvest of 127 whales.

Steller Sea Lion

    Steller sea lions are distributed mainly around the coasts to the 
outer continental shelf along the North Pacific rim from northern 
Hokkaido, Japan through the Kuril Islands and Okhotsk Sea, Aleutian 
Islands and central Bering Sea, southern coast of Alaska and south to 
California (Loughlin et al., 1984). Based on distribution, population 
response, and phenotypic and genotypic data, two separate stocks of 
Steller sea

[[Page 44037]]

lions are recognized within U. S. waters, with the population divided 
into western and eastern distinct population segments (DPS) at 
144[deg]W (Cape Suckling, Alaska) (Loughlin, 1997). The eastern DPS 
extends from California to Alaska, including the Gulf of Alaska, and is 
the only stock that may occur in Sinclair Inlet.
    According to NMFS' recent status review (NMFS, 2013), the best 
available information indicates that the overall abundance of eastern 
DPS Steller sea lions has increased for a sustained period of at least 
three decades while pup production has also increased significantly, 
especially since the mid-1990s. Johnson and Gelatt (2012) provided an 
analysis of growth trends of the entire eastern DPS from 1979-2010, 
indicating that the stock increased during this period at an annual 
rate of 4.2 percent (90% CI 3.7-4.6). Most of the overall increase 
occurred in the northern portion of the range (southeast Alaska and 
British Columbia), but pup counts in Oregon and California also 
increased significantly (e.g., Merrick et al., 1992; Sease et al., 
2001; Olesiuk and Trites, 2003; Fritz et al. 2008; Olesiuk, 2008; NMFS, 
2008, 2013). In Washington, Pitcher et al. (2007) reported that Steller 
sea lions, presumably immature animals and non-breeding adults, 
regularly used four haul-outs, including two ``major'' haul-outs (>50 
animals). The same study reported that the numbers of sea lions counted 
between 1989 and 2002 on Washington haul-outs increased significantly 
(average annual rate of 9.2 percent) (Pitcher et al., 2007). Although 
the stock size has increased, its status relative to OSP size is 
unknown. However, the consistent long-term estimated annual rate of 
increase may indicate that the stock is reaching OSP size (Allen and 
Angliss, 2014).
    The eastern stock breeds in rookeries located in southeast Alaska, 
British Columbia, Oregon, and California. There are no known breeding 
rookeries in Washington (Allen and Angliss, 2014) but eastern stock 
Steller sea lions are present year-round along the outer coast of 
Washington, including immature animals or non-breeding adults of both 
sexes. In 2011, the minimum count for Steller sea lions in Washington 
was 1,749 (Allen and Angliss, 2014), up from 516 in 2001 (Pitcher et 
al., 2007). In Washington, Steller sea lions primarily occur at haul-
out sites along the outer coast from the Columbia River to Cape 
Flattery and in inland waters sites along the Vancouver Island 
coastline of the Strait of Juan de Fuca (Jeffries et al., 2000; Olesiuk 
and Trites, 2003; Olesiuk, 2008). Numbers vary seasonally in Washington 
waters with peak numbers present during the fall and winter months 
(Jeffries et al., 2000). More recently, five winter haul-out sites used 
by adult and subadult Steller sea lions have been identified in Puget 
Sound (see Figure 4-2 of the Navy's applications). Numbers of animals 
observed at all of these sites combined were less than 200 individuals. 
The closest haul-out, with approximately 30 to 50 individuals near the 
Navy's Manchester Fuel Depot, occurs approximately 6.5 mi from the 
project site but is physically separated by various land masses and 
waterways. However, one Steller sea lion was observed hauled out on the 
floating security barrier at NBKB in November 2012. No permanent haul-
out has been identified in the project area and Steller sea lion 
presence is considered to be rare and seasonal.

Harbor Seal

    Harbor seals inhabit coastal and estuarine waters and shoreline 
areas of the northern hemisphere from temperate to polar regions. The 
eastern North Pacific subspecies is found from Baja California north to 
the Aleutian Islands and into the Bering Sea. Multiple lines of 
evidence support the existence of geographic structure among harbor 
seal populations from California to Alaska (e.g., O'Corry-Crowe et al., 
2003; Temte, 1986; Calambokidis et al., 1985; Kelly, 1981; Brown, 1988; 
Lamont, 1996; Burg, 1996). Harbor seals are generally non-migratory, 
and analysis of genetic information suggests that genetic differences 
increase with geographic distance (Westlake and O'Corry-Crowe, 2002). 
However, because stock boundaries are difficult to meaningfully draw 
from a biological perspective, three separate harbor seal stocks are 
recognized for management purposes along the west coast of the 
continental U.S.: (1) Inland waters of Washington (including Hood 
Canal, Puget Sound, and the Strait of Juan de Fuca out to Cape 
Flattery), (2) outer coast of Oregon and Washington, and (3) California 
(Carretta et al., 2014). Multiple stocks are recognized in Alaska. 
Samples from Washington, Oregon, and California demonstrate a high 
level of genetic diversity and indicate that the harbor seals of 
Washington inland waters possess unique haplotypes not found in seals 
from the coasts of Washington, Oregon, and California (Lamont et al., 
1996).
    Recent genetic evidence suggests that harbor seals of Washington 
inland waters have sufficient population structure to warrant division 
into multiple distinct stocks (Huber et al., 2010, 2012). Based on 
studies of pupping phenology, mitochondrial DNA, and microsatellite 
variation, Carretta et al. (2014) divide the Washington inland waters 
stock into three new populations, and present these as stocks: (1) 
Southern Puget Sound (south of the Tacoma Narrows Bridge); (2) 
Washington northern inland waters (including Puget Sound north of the 
Tacoma Narrows Bridge, the San Juan Islands, and the Strait of Juan de 
Fuca); and (3) Hood Canal. Only the northern inland waters stock of 
harbor seals is expected to occur in the action area.
    The best available abundance estimate was derived from aerial 
surveys of harbor seals in Washington conducted during the pupping 
season in 1999, during which time the total numbers of hauled-out seals 
(including pups) were counted (Jeffries et al., 2003). Radio-tagging 
studies conducted at six locations collected information on harbor seal 
haul-out patterns in 1991-92, resulting in a pooled correction factor 
(across three coastal and three inland sites) of 1.53 to account for 
animals in the water which are missed during the aerial surveys (Huber 
et al., 2001), which, coupled with the aerial survey counts, provides 
the abundance estimate (see Table 1).
    Harbor seal counts in Washington State increased at an annual rate 
of six percent from 1983-96, increasing to ten percent for the period 
1991-96 (Jeffries et al., 1997). The population is thought to be 
stable, and the Washington inland waters stock is considered to be 
within its OSP size (Jeffries et al., 2003).
    Harbor seal numbers increase from January through April and then 
decrease from May through August as the harbor seals move to adjacent 
bays on the outer coast of Washington for the pupping season. From 
April through mid-July, female harbor seals haul out on the outer coast 
of Washington at pupping sites to give birth. Harbor seals are expected 
to occur in Sinclair Inlet and NBKB at all times of the year. No 
permanent haul-out has been identified at NBKB. The nearest known haul-
outs are along the south side of Sinclair Inlet on log breakwaters at 
several marinas in Port Orchard, approximately one mile from Pier 6. An 
additional haul-out location in Dyes Inlet, approximately 8.5 km north 
and west (shoreline distance), was believed to support less than 100 
seals (Jeffries et al., 2000). Please see Figure 4-2 of the Navy's 
application.

California Sea Lion

    California sea lions range from the Gulf of California north to the 
Gulf of

[[Page 44038]]

Alaska, with breeding areas located in the Gulf of California, western 
Baja California, and southern California. Five genetically distinct 
geographic populations have been identified: (1) Pacific temperate, (2) 
Pacific subtropical, and (3-5) southern, central, and northern Gulf of 
California (Schramm et al., 2009). Rookeries for the Pacific temperate 
population are found within U.S. waters and just south of the U.S.-
Mexico border, and animals belonging to this population may be found 
from the Gulf of Alaska to Mexican waters off Baja California. For 
management purposes, a stock of California sea lions comprising those 
animals at rookeries within the U.S. is defined (i.e., the U.S. stock 
of California sea lions) (Carretta et al., 2014). Pup production at the 
Coronado Islands rookery in Mexican waters is considered an 
insignificant contribution to the overall size of the Pacific temperate 
population (Lowry and Maravilla-Chavez, 2005).
    Trends in pup counts from 1975 through 2008 have been assessed for 
four rookeries in southern California and for haul-outs in central and 
northern California. During this time period counts of pups increased 
at an annual rate of 5.4 percent, excluding six El Nino years when pup 
production declined dramatically before quickly rebounding (Carretta et 
al., 2014). The maximum population growth rate was 9.2 percent when pup 
counts from the El Ni[ntilde]o years were removed. There are 
indications that the California sea lion may have reached or is 
approaching carrying capacity, although more data are needed to confirm 
that leveling in growth persists (Carretta et al., 2014).
    Sea lion mortality has been linked to the algal-produced neurotoxin 
domoic acid (Scholin et al., 2000). Future mortality may be expected to 
occur, due to the sporadic occurrence of such harmful algal blooms. 
There is currently an Unusual Mortality Event (UME) declaration in 
effect for California sea lions. Beginning in January 2013, elevated 
strandings of California sea lion pups have been observed in southern 
California, with live sea lion strandings nearly three times higher 
than the historical average. Findings to date indicate that a likely 
contributor to the large number of stranded, malnourished pups was a 
change in the availability of sea lion prey for nursing mothers, 
especially sardines. The causes and mechanisms of this UME remain under 
investigation (www.nmfs.noaa.gov/pr/health/mmume/californiasealions2013.htm; accessed July 13, 2015).
    California sea lions were not recorded in Puget Sound until 
approximately 1979 (Steiger and Calambokidis, 1986). Everitt et al. 
(1980) reported the initial occurrence of large numbers in northern 
Puget Sound in the spring of that year. Similar sightings and increases 
in numbers were documented throughout the region after the initial 
sighting (Steiger and Calambokidis 1986), including urbanized areas 
such as Elliot Bay near Seattle and heavily used areas of central Puget 
Sound (Gearin et al., 1986). California sea lions now use haul-out 
sites within all regions of Washington inland waters (Jeffries et al., 
2000). California sea lions migrate northward along the coast to 
central and northern California, Oregon, Washington, and Vancouver 
Island during the non-breeding season from September to May and return 
south the following spring (Mate, 1975; Bonnell et al., 1983). Jeffries 
et al. (2000) estimated that 3,000 to 5,000 individuals make this trip, 
with peak numbers of up to 1,000 occurring in Puget Sound during this 
time period. The California sea lion population has grown 
substantially, and it is likely that the numbers migrating to 
Washington inland waters have increased as well.
    Occurrence in Puget Sound is typically between September and June 
with peak abundance between September and May. During summer months 
(June through August) and associated breeding periods, California sea 
lions are largely returning to rookeries in California and are not 
present in large numbers in Washington inland waters. They are known to 
utilize a diversity of man-made structures for hauling out (Riedman, 
1990) and, although there are no regular California sea lion haul-outs 
known within Sinclair Inlet (Jeffries et al., 2000), they are 
frequently observed hauled out at several opportune areas at NBKB 
(e.g., floating security fence; see Figures 4-1 and 4-2 of the Navy's 
application). The next nearest recorded haul-outs are navigation buoys 
and net pens in Rich Passage, approximately 10 km east of NBKB 
(Jeffries et al., 2000).

Killer Whale

    Killer whales are one of the most cosmopolitan marine mammals, 
found in all oceans with no apparent restrictions on temperature or 
depth, although they do occur at higher densities in colder, more 
productive waters at high latitudes and are more common in nearshore 
waters (Leatherwood and Dahlheim, 1978; Forney and Wade, 2006). Killer 
whales are found throughout the North Pacific, including the entire 
Alaska coast, in British Columbia and Washington inland waterways, and 
along the outer coasts of Washington, Oregon, and California. On the 
basis of differences in morphology, ecology, genetics, and behavior, 
populations of killer whales have largely been classified as 
``resident'', ``transient'', or ``offshore'' (e.g., Dahlheim et al., 
2008). Several studies have also provided evidence that these ecotypes 
are genetically distinct, and that further genetic differentiation is 
present between subpopulations of the resident and transient ecotypes 
(e.g., Barrett-Lennard, 2000). The taxonomy of killer whales is 
unresolved, with expert opinion generally following one of two lines: 
Killer whales are either (1) a single highly variable species, with 
locally differentiated ecotypes representing recently evolved and 
relatively ephemeral forms not deserving species status, or (2) 
multiple species, supported by the congruence of several lines of 
evidence for the distinctness of sympatrically occurring forms (Krahn 
et al., 2004). Resident and transient whales are currently considered 
to be unnamed subspecies (Committee on Taxonomy, 2014).
    The resident and transient populations have been divided further 
into different subpopulations on the basis of genetic analyses, 
distribution, and other factors. Recognized stocks in the North Pacific 
include Alaska residents; northern residents; southern residents; Gulf 
of Alaska, Aleutian Islands, and Bering Sea transients; and west coast 
transients, along with a single offshore stock. See Allen and Angliss 
(2014) for more detail about these stocks. West coast transient killer 
whales, which occur from California through southeastern Alaska, are 
the only type expected to potentially occur in the project area.
    It is thought that the stock grew rapidly from the mid-1970s to 
mid-1990s as a result of a combination of high birth rate, survival, as 
well as greater immigration of animals into the nearshore study area 
(DFO, 2009). The rapid growth of the population during this period 
coincided with a dramatic increase in the abundance of the whales' 
primary prey, harbor seals, in nearshore waters. Population growth 
began slowing in the mid-1990s and has continued to slow in recent 
years (DFO, 2009). Population trends and status of this stock relative 
to its OSP level are currently unknown. Analyses in DFO (2009) 
estimated a rate of increase of about six percent per year from 1975 to 
2006, but this included recruitment of non-calf whales into the 
population.

[[Page 44039]]

    Transient occurrence in inland waters appears to peak during August 
and September which is the peak time for harbor seal pupping, weaning, 
and post-weaning (Baird and Dill, 1995). The number of west coast 
transients in Washington inland waters at any one time was considered 
likely to be fewer than twenty individuals by Wiles (2004), although 
more recent information (2004-10) suggests that transient use of inland 
waters has increased, possibly due to increasing prey abundance 
(Houghton et al., in prep.). However, Sinclair Inlet is a shallow bay 
located approximately eight miles through various waterways from the 
main open waters of Puget Sound, where killer whales occur more 
frequently, and killer whale occurrence in Sinclair Inlet is uncommon. 
From December 2002 to June 2014, there were two reports of transient 
killer whales transiting through the area around NBKB, with both 
reports occurring in May (a group of up to twelve in 2004 and a group 
of up to five in 2012; www.orcanetwork.org).

Gray Whale

    Gray whales are found in shallow coastal waters, migrating between 
summer feeding areas in the north and winter breeding areas in the 
south. Gray whales were historically common throughout the northern 
hemisphere but are now found only in the Pacific, where two populations 
are recognized, Eastern and Western North Pacific (ENP and WNP). ENP 
whales breed and calve primarily in areas off Baja California and in 
the Gulf of California. From February to May, whales typically migrate 
northbound to summer/fall feeding areas in the Chukchi and northern 
Bering Seas, with the southbound return to calving areas typically 
occurring in November and December. WNP whales are known to feed in the 
Okhotsk Sea and off of Kamchatka before migrating south to poorly known 
wintering grounds, possibly in the South China Sea.
    The two populations have historically been considered 
geographically isolated from each other; however, recent data from 
satellite-tracked whales indicates that there is some overlap between 
the stocks. Two WNP whales were tracked from Russian foraging areas 
along the Pacific rim to Baja California (Mate et al., 2011), and, in 
one case where the satellite tag remained attached to the whale for a 
longer period, a WNP whale was tracked from Russia to Mexico and back 
again (IWC, 2012). Between 22-24 WNP whales are known to have occurred 
in the eastern Pacific through comparisons of ENP and WNP photo-
identification catalogs (IWC, 2012; Weller et al., 2011; Burdin et al., 
2011), and WNP animals comprised 8.1 percent of gray whales identified 
during a recent field season off of Vancouver Island (Weller et al., 
2012). In addition, two genetic matches of WNP whales have been 
recorded off of Santa Barbara, CA (Lang et al., 2011a). More recently, 
Urban et al. (2013) compared catalogs of photo-identified individuals 
from Mexico with photographs of whales off Russia and reported a total 
of 21 matches. Therefore, a portion of the WNP population is assumed to 
migrate, at least in some years, to the eastern Pacific during the 
winter breeding season. However, no WNP whales are known to have 
occurred in Washington inland waters. The likelihood of any gray whale 
being exposed to project sound to the degree considered in this 
document is already low, given the uncommon occurrence of gray whales 
in the project area. In the event that a gray whale did occur in the 
project area, it is extremely unlikely that it would be one of the 
approximately twenty WNP whales that have been documented in the 
eastern Pacific (less than one percent probability). The WNP population 
is listed as endangered under the ESA and depleted under the MMPA as a 
foreign stock; however, the likelihood that a WNP whale would be 
present in the action area is insignificant and discountable.
    In addition, recent studies provide new information on gray whale 
stock structure within the ENP, with emphasis on whales that feed 
during summer off the Pacific coast between northern California and 
southeastern Alaska, occasionally as far north as Kodiak Island, Alaska 
(Gosho et al., 2011). These whales, collectively known as the Pacific 
Coast Feeding Group (PCFG), are a trans-boundary population with the 
U.S. and Canada and are defined by the International Whaling Commission 
(IWC) as follows: Gray whales observed between June 1 to November 30 
within the region between northern California and northern Vancouver 
Island (from 41[deg]N to 52[deg]N) and photo-identified within this 
area during two or more years (Carretta et al., 2013). Photo-
identification and satellite tagging studies provide data on abundance, 
population structure, and movements of PCFG whales (Calambokidis et 
al., 2010; Mate et al.; 2010; Gosho et al., 2011). These data in 
conjunction with genetic studies (e.g., Frasier et al., 2011; Lang et 
al., 2011b) indicate that the PCFG may be a demographically distinct 
feeding aggregation, and may warrant consideration as a distinct stock 
(Carretta et al., 2014). It is unknown whether PCFG whales would be 
encountered in Washington inland waters. Here, we consider only a 
single stock of ENP whales.
    The ENP population of gray whales, which is managed as a stock, was 
removed from ESA protection in 1994, is not currently protected under 
the ESA, and is not listed as depleted under the MMPA. Punt and Wade 
(2010) estimated the ENP population was at 91 percent of carrying 
capacity and at 129 percent of the maximum net productivity level and 
therefore within the range of its optimum sustainable population. The 
estimated annual rate of increase from 1967-88, based on a revised 
abundance time series from Laake et al. (2009), is 3.2 percent (Punt 
and Wade, 2010), and the population size of the ENP gray whale stock 
has been increasing over the past several decades despite a west coast 
UME from 1999-2001. It is likely that oceanographic factors limited 
food availability (LeBouef et al., 2000; Moore et al., 2001; Minobe, 
2002; Gulland et al., 2005), with resulting declines in survival rates 
of adults (Punt and Wade, 2012). The population has recovered to levels 
seen prior to the UME (Carretta et al., 2014).
    Gray whales generally migrate southbound past Washington in late 
December and January, and transit past Washington on the northbound 
return in March to May. Gray whales do not generally make use of 
Washington inland waters, but have been observed in certain portions of 
those waters in all months of the year, with most records occurring 
from March through June (Calambokidis et al., 2010; 
www.orcanetwork.org) and associated with regular feeding areas. Usually 
fewer than twenty gray whales visit the inner marine waters of 
Washington and British Columbia beginning in about January, with some 
staying until summer. Six to ten of these are PCFG whales that return 
most years to feeding sites near Whidbey and Camano Islands in northern 
Puget Sound. The remaining individuals occurring in any given year 
generally appear unfamiliar with feeding areas, often arrive emaciated, 
and commonly die of starvation (WDFW, 2012). From December 2002 to June 
2014, the Orca Network sightings database reports four occurrences of 
gray whales in the project area during the in-water work window 
(www.orcanetwork.org). Three sightings occurred during the winter of 
2008-09, and one stranding was reported in January 2013. The necropsy 
of the whale indicated that it was a juvenile

[[Page 44040]]

male in poor nutritional health. Two other strandings have been 
recorded in the project area, in May 2005 and July 2011.

Potential Effects of the Specified Activity on Marine Mammals

    This section includes a summary and discussion of the ways that 
components of the specified activity may impact marine mammals. This 
discussion also includes reactions that we consider to rise to the 
level of a take and those that we do not consider to rise to the level 
of a take (for example, with acoustics, we may include a discussion of 
studies that showed animals not reacting at all to sound or exhibiting 
barely measurable avoidance). This section is intended as a background 
of potential effects and does not consider either the specific manner 
in which this activity will be carried out or the mitigation that will 
be implemented, and how either of those will shape the anticipated 
impacts from this specific activity. The Estimated Take by Incidental 
Harassment section later in this document will include a quantitative 
analysis of the number of individuals that are expected to be taken by 
this activity. The Negligible Impact Analyses section will include the 
analysis of how this specific activity will impact marine mammals and 
will consider the content of this section, the Estimated Take by 
Incidental Harassment section, the Proposed Mitigation section, and the 
Anticipated Effects on Marine Mammal Habitat section to draw 
conclusions regarding the likely impacts of this activity on the 
reproductive success or survivorship of individuals and from that on 
the affected marine mammal populations or stocks. In the following 
discussion, we provide general background information on sound and 
marine mammal hearing before considering potential effects to marine 
mammals from sound produced by vibratory and impact pile driving.

Description of Sound Sources

    Sound travels in waves, the basic components of which are 
frequency, wavelength, velocity, and amplitude. Frequency is the number 
of pressure waves that pass by a reference point per unit of time and 
is measured in hertz (Hz) or cycles per second. Wavelength is the 
distance between two peaks of a sound wave; lower frequency sounds have 
longer wavelengths than higher frequency sounds and attenuate 
(decrease) more rapidly in shallower water. Amplitude is the height of 
the sound pressure wave or the `loudness' of a sound and is typically 
measured using the decibel (dB) scale. A dB is the ratio between a 
measured pressure (with sound) and a reference pressure (sound at a 
constant pressure, established by scientific standards). It is a 
logarithmic unit that accounts for large variations in amplitude; 
therefore, relatively small changes in dB ratings correspond to large 
changes in sound pressure. When referring to sound pressure levels 
(SPLs; the sound force per unit area), sound is referenced in the 
context of underwater sound pressure to 1 microPascal ([mu]Pa). One 
pascal is the pressure resulting from a force of one newton exerted 
over an area of one square meter. The source level (SL) represents the 
sound level at a distance of 1 m from the source (referenced to 1 
[mu]Pa). The received level is the sound level at the listener's 
position. Note that all underwater sound levels in this document are 
referenced to a pressure of 1 [micro]Pa and all airborne sound levels 
in this document are referenced to a pressure of 20 [micro]Pa.
    Root mean square (rms) is the quadratic mean sound pressure over 
the duration of an impulse. Rms is calculated by squaring all of the 
sound amplitudes, averaging the squares, and then taking the square 
root of the average (Urick, 1983). Rms accounts for both positive and 
negative values; squaring the pressures makes all values positive so 
that they may be accounted for in the summation of pressure levels 
(Hastings and Popper, 2005). This measurement is often used in the 
context of discussing behavioral effects, in part because behavioral 
effects, which often result from auditory cues, may be better expressed 
through averaged units than by peak pressures.
    When underwater objects vibrate or activity occurs, sound-pressure 
waves are created. These waves alternately compress and decompress the 
water as the sound wave travels. Underwater sound waves radiate in all 
directions away from the source (similar to ripples on the surface of a 
pond), except in cases where the source is directional. The 
compressions and decompressions associated with sound waves are 
detected as changes in pressure by aquatic life and man-made sound 
receptors such as hydrophones.
    Even in the absence of sound from the specified activity, the 
underwater environment is typically loud due to ambient sound. Ambient 
sound is defined as environmental background sound levels lacking a 
single source or point (Richardson et al., 1995), and the sound level 
of a region is defined by the total acoustical energy being generated 
by known and unknown sources. These sources may include physical (e.g., 
waves, earthquakes, ice, atmospheric sound), biological (e.g., sounds 
produced by marine mammals, fish, and invertebrates), and anthropogenic 
sound (e.g., vessels, dredging, aircraft, construction). A number of 
sources contribute to ambient sound, including the following 
(Richardson et al., 1995):
     Wind and waves: The complex interactions between wind and 
water surface, including processes such as breaking waves and wave-
induced bubble oscillations and cavitation, are a main source of 
naturally occurring ambient noise for frequencies between 200 Hz and 50 
kHz (Mitson, 1995). In general, ambient sound levels tend to increase 
with increasing wind speed and wave height. Surf noise becomes 
important near shore, with measurements collected at a distance of 8.5 
km from shore showing an increase of 10 dB in the 100 to 700 Hz band 
during heavy surf conditions.
     Precipitation: Sound from rain and hail impacting the 
water surface can become an important component of total noise at 
frequencies above 500 Hz, and possibly down to 100 Hz during quiet 
times.
     Biological: Marine mammals can contribute significantly to 
ambient noise levels, as can some fish and shrimp. The frequency band 
for biological contributions is from approximately 12 Hz to over 100 
kHz.
     Anthropogenic: Sources of ambient noise related to human 
activity include transportation (surface vessels and aircraft), 
dredging and construction, oil and gas drilling and production, seismic 
surveys, sonar, explosions, and ocean acoustic studies. Shipping noise 
typically dominates the total ambient noise for frequencies between 20 
and 300 Hz. In general, the frequencies of anthropogenic sounds are 
below 1 kHz and, if higher frequency sound levels are created, they 
attenuate rapidly (Richardson et al., 1995). Sound from identifiable 
anthropogenic sources other than the activity of interest (e.g., a 
passing vessel) is sometimes termed background sound, as opposed to 
ambient sound.
    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

[[Page 44041]]

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.
    The underwater acoustic environment in Sinclair Inlet is likely to 
be dominated by noise from day-to-day port and vessel activities. 
Normal port activities include vessel traffic from large ships, 
submarines, support vessels, and security boats, and loading and 
maintenance operations. Other sources of human-generated underwater 
sound in the area are recreational vessels, industrial ship noise, and 
ferry traffic at the adjacent Washington State Ferry Terminal. In 2009, 
the average broadband (100 Hz-20 kHz) underwater noise level at NBK 
Bangor in the Hood Canal was measured at 114 dB (Slater, 2009), which 
is within the range of levels reported for a number of sites within the 
greater Puget Sound region (95-135 dB; e.g., Carlson et al., 2005; 
Veirs and Veirs, 2006). Measurements near ferry terminals in Puget 
Sound, such as the Bremerton terminal adjacent to NBKB, resulted in 
median noise levels (50% cumulative distribution function) between 106 
and 133 dB (Laughlin, 2012). Although no specific measurements have 
been made at NBKB, it is reasonable to believe that levels may 
generally be higher than at NBK Bangor as there is a greater degree of 
activity, that levels periodically exceed the 120-dB threshold and, 
therefore, that the high levels of anthropogenic activity in the area 
create an environment far different from quieter habitats where 
behavioral reactions to sounds around the 120-dB threshold have been 
observed (e.g., Malme et al., 1984, 1988).
    Known sound levels and frequency ranges associated with 
anthropogenic sources similar to those that would be used for this 
project are summarized in Table 2. Details of the source types are 
described in the following text.

                          Table 2--Representative Sound Levels of Anthropogenic Sources
----------------------------------------------------------------------------------------------------------------
                                Frequency   Underwater sound
         Sound source          range  (Hz)        level                            Reference
----------------------------------------------------------------------------------------------------------------
Small vessels................    250-1,000  151 dB rms at 1   Richardson et al., 1995.
                                             m.
Tug docking gravel barge.....    200-1,000  149 dB rms at     Blackwell and Greene, 2002.
                                             100 m.
Vibratory driving of 72-in        10-1,500  180 dB rms at 10  Reyff, 2007.
 steel pipe pile.                            m.
Impact driving of 36-in steel     10-1,500  195 dB rms at 10  Laughlin, 2007.
 pipe pile.                                  m.
Impact driving of 66-in cast-     10-1,500  195 dB rms at 10  Reviewed in Hastings and Popper, 2005.
 in-steel-shell (CISS) pile.                 m.
----------------------------------------------------------------------------------------------------------------

    In-water construction activities associated with the project would 
include impact pile driving and vibratory pile driving. The sounds 
produced by these activities fall into one of two general sound types: 
pulsed and non-pulsed (defined in the following). 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). Please see 
Southall et al., (2007) for an in-depth discussion of these concepts.
    Pulsed sound sources (e.g., explosions, gunshots, sonic booms, 
impact pile driving) produce signals that are brief (typically 
considered to be less than one second), broadband, atonal transients 
(ANSI, 1986; Harris, 1998; NIOSH, 1998; ISO, 2003; ANSI, 2005) and 
occur either as isolated events or repeated in some succession. Pulsed 
sounds are all characterized by a relatively rapid rise from ambient 
pressure to a maximal pressure value followed by a rapid decay period 
that may include a period of diminishing, oscillating maximal and 
minimal pressures, and generally have an increased capacity to induce 
physical injury as compared with sounds that lack these features.
    Non-pulsed sounds can be tonal, narrowband, or broadband, brief or 
prolonged, and may be either continuous or non-continuous (ANSI, 1995; 
NIOSH, 1998). Some of these non-pulsed sounds can be transient signals 
of short duration but without the essential properties of pulses (e.g., 
rapid rise time). Examples of non-pulsed sounds include those produced 
by vessels, aircraft, machinery operations such as drilling or 
dredging, vibratory pile driving, and active sonar systems (such as 
those used by the U.S. Navy). The duration of such sounds, as received 
at a distance, can be greatly extended in a highly reverberant 
environment.
    Impact hammers operate by repeatedly dropping a heavy piston onto a 
pile to drive the pile into the substrate. Sound generated by impact 
hammers is characterized by rapid rise times and high peak levels, a 
potentially injurious combination (Hastings and Popper, 2005). 
Vibratory hammers install piles by vibrating them and allowing the 
weight of the hammer to push them into the sediment. Vibratory hammers 
produce significantly less sound than impact hammers. Peak SPLs may be 
180 dB or greater, but are generally 10 to 20 dB lower than SPLs 
generated during impact pile driving of the same-sized pile (Oestman et 
al., 2009). Rise time is slower, reducing the probability and severity 
of injury, and sound energy is distributed over a greater amount of 
time (Nedwell and Edwards, 2002; Carlson et al., 2005).

Marine Mammal Hearing

    Hearing is the most important sensory modality for marine mammals, 
and exposure to sound can have deleterious effects. To appropriately 
assess these potential effects, 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 
measured or estimated hearing ranges on the basis of available 
behavioral data, audiograms derived using auditory evoked potential 
techniques, anatomical modeling, and other data. The lower and/or upper 
frequencies for some of these functional hearing groups have been 
modified from those designated by Southall et al. (2007). The 
functional groups and the associated frequencies are indicated below 
(note that these frequency ranges do not necessarily correspond to the 
range of best hearing, which varies by species):

[[Page 44042]]

     Low-frequency cetaceans (mysticetes): Functional hearing 
is estimated to occur between approximately 7 Hz and 25 kHz (extended 
from 22 kHz; Watkins, 1986; Au et al., 2006; Lucifredi and Stein, 2007; 
Ketten and Mountain, 2009; Tubelli et al., 2012);
     Mid-frequency cetaceans (larger toothed whales, beaked 
whales, and most delphinids): Functional hearing is estimated to occur 
between approximately 150 Hz and 160 kHz;
     High-frequency cetaceans (porpoises, river dolphins, and 
members of the genera Kogia and Cephalorhynchus; now considered to 
include two members of the genus Lagenorhynchus on the basis of recent 
echolocation data and genetic data [May-Collado and Agnarsson, 2006; 
Kyhn et al. 2009, 2010; Tougaard et al. 2010]): Functional hearing is 
estimated to occur between approximately 200 Hz and 180 kHz; and
     Pinnipeds in water: Functional hearing is estimated to 
occur between approximately 75 Hz to 100 kHz for Phocidae (true seals) 
and between 100 Hz and 40 kHz for Otariidae (eared seals), with the 
greatest sensitivity between approximately 700 Hz and 20 kHz. 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 et al., 
2013).
    There are five marine mammal species (two cetacean and three 
pinniped [two otariid and one phocid] species) with expected potential 
to co-occur with Navy construction activities. Please refer to Table 1. 
Of the two cetacean species that may be present, the killer whale is 
classified as mid-frequency and the gray whale is classified as low-
frequency.

Acoustic Effects, Underwater

    Potential Effects of Pile Driving Sound--The effects of sounds from 
pile driving might result in one or more of the following: Temporary or 
permanent hearing impairment, non-auditory physical or physiological 
effects, behavioral disturbance, and masking (Richardson et al., 1995; 
Gordon et al., 2004; Nowacek et al., 2007; Southall et al., 2007). The 
effects of pile driving on marine mammals are dependent on several 
factors, including the size, type, and depth of the animal; the depth, 
intensity, and duration of the pile driving sound; the depth of the 
water column; the substrate of the habitat; the standoff distance 
between the pile and the animal; and the sound propagation properties 
of the environment. Impacts to marine mammals from pile driving 
activities are expected to result primarily from acoustic pathways. As 
such, the degree of effect is intrinsically related to the received 
level and duration of the sound exposure, which are in turn influenced 
by the distance between the animal and the source. The further away 
from the source, the less intense the exposure should be. The substrate 
and depth of the habitat affect the sound propagation properties of the 
environment. Shallow environments are typically more structurally 
complex, which leads to rapid sound attenuation. In addition, 
substrates that are soft (e.g., sand) would absorb or attenuate the 
sound more readily than hard substrates (e.g., rock) which may reflect 
the acoustic wave. Soft porous substrates would also likely require 
less time to drive the pile, and possibly less forceful equipment, 
which would ultimately decrease the intensity of the acoustic source.
    In the absence of mitigation, impacts to marine species would be 
expected to result from physiological and behavioral responses to both 
the type and strength of the acoustic signature (Viada et al., 2008). 
The type and severity of behavioral impacts are more difficult to 
define due to limited studies addressing the behavioral effects of 
impulsive sounds on marine mammals. Potential effects from impulsive 
sound sources can range in severity from effects such as behavioral 
disturbance or tactile perception to physical discomfort, slight injury 
of the internal organs and the auditory system, or mortality (Yelverton 
et al., 1973).
    Hearing Impairment and Other Physical Effects--Marine mammals 
exposed to high intensity sound repeatedly or for prolonged periods can 
experience hearing threshold shift (TS), which is the loss of hearing 
sensitivity at certain frequency ranges (Kastak et al., 1999; Schlundt 
et al., 2000; Finneran et al., 2002, 2005). TS can be permanent (PTS), 
in which case the loss of hearing sensitivity is not recoverable, or 
temporary (TTS), in which case the animal's hearing threshold would 
recover over time (Southall et al., 2007). Marine mammals depend on 
acoustic cues for vital biological functions, (e.g., orientation, 
communication, finding prey, avoiding predators); thus, TTS may result 
in reduced fitness in survival and reproduction. However, this depends 
on the frequency and duration of TTS, as well as the biological context 
in which it occurs. TTS of limited duration, occurring in a frequency 
range that does not coincide with that used for recognition of 
important acoustic cues, would have little to no effect on an animal's 
fitness. Repeated sound exposure that leads to TTS could cause PTS. PTS 
constitutes injury, but TTS does not (Southall et al., 2007). The 
following subsections discuss in somewhat more detail the possibilities 
of TTS, PTS, and non-auditory physical effects.
    Temporary Threshold Shift--TTS is the mildest form of hearing 
impairment that can occur during exposure to a strong sound (Kryter, 
1985). While experiencing TTS, the hearing threshold rises, and a sound 
must be stronger in order to be heard. In terrestrial mammals, TTS can 
last from minutes or hours to days (in cases of strong TTS). For sound 
exposures at or somewhat above the TTS threshold, hearing sensitivity 
in both terrestrial and marine mammals recovers rapidly after exposure 
to the sound ends. Few data on sound levels and durations necessary to 
elicit mild TTS have been obtained for marine mammals, and none of the 
published data concern TTS elicited by exposure to multiple pulses of 
sound. Available data on TTS in marine mammals are summarized in 
Southall et al. (2007).
    Given the available data, the received level of a single pulse 
(with no frequency weighting) might need to be approximately 186 dB re 
1 [mu]Pa\2\-s (i.e., 186 dB sound exposure level [SEL] or approximately 
221-226 dB p-p [peak]) in order to produce brief, mild TTS. Exposure to 
several strong pulses that each have received levels near 190 dB rms 
(175-180 dB SEL) might result in cumulative exposure of approximately 
186 dB SEL and thus slight TTS in a small odontocete, assuming the TTS 
threshold is (to a first approximation) a function of the total 
received pulse energy.
    The above TTS information for odontocetes is derived from studies 
on the bottlenose dolphin (Tursiops truncatus) and beluga whale 
(Delphinapterus leucas). There is no published TTS information for 
other species of cetaceans. However, preliminary evidence from a harbor 
porpoise exposed to pulsed sound suggests that its TTS threshold may 
have been lower (Lucke et al., 2009). As summarized above, data that 
are now available imply that TTS is unlikely to occur unless 
odontocetes are exposed to pile driving pulses stronger than 180 dB re 
1 [mu]Pa rms.
    Permanent Threshold Shift--When PTS occurs, there is physical 
damage to the sound receptors in the ear. In severe cases, there can be 
total or partial

[[Page 44043]]

deafness, while in other cases the animal has an impaired ability to 
hear sounds in specific frequency ranges (Kryter, 1985). There is no 
specific evidence that exposure to pulses of sound can cause PTS in any 
marine mammal. However, given the possibility that mammals close to a 
sound source might incur TTS, there has been further speculation about 
the possibility that some individuals might incur PTS. Single or 
occasional occurrences of mild TTS are not indicative of permanent 
auditory damage, but repeated or (in some cases) single exposures to a 
level well above that causing TTS onset might elicit PTS.
    Relationships between TTS and PTS thresholds have not been studied 
in marine mammals but are assumed to be similar to those in humans and 
other terrestrial mammals. PTS might occur at a received sound level at 
least several decibels above that inducing mild TTS if the animal were 
exposed to strong sound pulses with rapid rise time. Based on data from 
terrestrial mammals, a precautionary assumption is that the PTS 
threshold for impulse sounds (such as pile driving pulses as received 
close to the source) is at least 6 dB higher than the TTS threshold on 
a peak-pressure basis and probably greater than 6 dB (Southall et al., 
2007). On an SEL basis, Southall et al. (2007) estimated that received 
levels would need to exceed the TTS threshold by at least 15 dB for 
there to be risk of PTS. Thus, for cetaceans, Southall et al. (2007) 
estimate that the PTS threshold might be an M-weighted SEL (for the 
sequence of received pulses) of approximately 198 dB re 1 [mu]Pa\2\-s 
(15 dB higher than the TTS threshold for an impulse). Given the higher 
level of sound necessary to cause PTS as compared with TTS, it is 
considerably less likely that PTS could occur.
    Measured source levels from impact pile driving can be as high as 
214 dB rms. Although no marine mammals have been shown to experience 
TTS or PTS as a result of being exposed to pile driving activities, 
captive bottlenose dolphins and beluga whales exhibited changes in 
behavior when exposed to strong pulsed sounds (Finneran et al., 2000, 
2002, 2005). The animals tolerated high received levels of sound before 
exhibiting aversive behaviors. Experiments on a beluga whale showed 
that exposure to a single watergun impulse at a received level of 207 
kPa (30 psi) p-p, which is equivalent to 228 dB p-p, resulted in a 7 
and 6 dB TTS in the beluga whale at 0.4 and 30 kHz, respectively. 
Thresholds returned to within 2 dB of the pre-exposure level within 
four minutes of the exposure (Finneran et al., 2002). Although the 
source level of pile driving from one hammer strike is expected to be 
much lower than the single watergun impulse cited here, animals being 
exposed for a prolonged period to repeated hammer strikes could receive 
more sound exposure in terms of SEL than from the single watergun 
impulse (estimated at 188 dB re 1 [mu]Pa\2\-s) in the aforementioned 
experiment (Finneran et al., 2002). However, in order for marine 
mammals to experience TTS or PTS, the animals have to be close enough 
to be exposed to high intensity sound levels for a prolonged period of 
time. Based on the best scientific information available, these SPLs 
are far below the thresholds that could cause TTS or the onset of PTS.
    Non-auditory Physiological Effects--Non-auditory physiological 
effects or injuries that theoretically might occur in marine mammals 
exposed to strong underwater sound include stress, neurological 
effects, bubble formation, resonance effects, and other types of organ 
or tissue damage (Cox et al., 2006; Southall et al., 2007). Studies 
examining such effects are limited. In general, little is known about 
the potential for pile driving to cause auditory impairment or other 
physical effects in marine mammals. Available data suggest that such 
effects, if they occur at all, would presumably be limited to short 
distances from the sound source and to activities that extend over a 
prolonged period. The available data do not allow identification of a 
specific exposure level above which non-auditory effects can be 
expected (Southall et al., 2007) or any meaningful quantitative 
predictions of the numbers (if any) of marine mammals that might be 
affected in those ways. Marine mammals that show behavioral avoidance 
of pile driving, including some odontocetes and some pinnipeds, are 
especially unlikely to incur auditory impairment or non-auditory 
physical effects.

Disturbance Reactions

    Disturbance includes a variety of effects, including subtle changes 
in behavior, more conspicuous changes in activities, and displacement. 
Behavioral responses to sound are highly variable and context-specific 
and reactions, if any, depend on species, state of maturity, 
experience, current activity, reproductive state, auditory sensitivity, 
time of day, and many other factors (Richardson et al., 1995; Wartzok 
et al., 2003; Southall et al., 2007).
    Habituation can occur when an animal's response to a stimulus wanes 
with repeated exposure, usually in the absence of unpleasant associated 
events (Wartzok et al., 2003). Animals are most likely to habituate to 
sounds that are predictable and unvarying. The opposite process is 
sensitization, when an unpleasant experience leads to subsequent 
responses, often in the form of avoidance, at a lower level of 
exposure. Behavioral state may affect the type of response as well. For 
example, animals that are resting may show greater behavioral change in 
response to disturbing sound levels than animals that are highly 
motivated to remain in an area for feeding (Richardson et al., 1995; 
NRC, 2003; Wartzok et al., 2003).
    Controlled experiments with captive marine mammals showed 
pronounced behavioral reactions, including avoidance of loud sound 
sources (Ridgway et al., 1997; Finneran et al., 2003). Observed 
responses of wild marine mammals to loud pulsed sound sources 
(typically seismic guns or acoustic harassment devices, but also 
including pile driving) have been varied but often consist of avoidance 
behavior or other behavioral changes suggesting discomfort (Morton and 
Symonds, 2002; Thorson and Reyff, 2006; see also Gordon et al., 2004; 
Wartzok et al., 2003; Nowacek et al., 2007). Responses to continuous 
sound, such as vibratory pile installation, have not been documented as 
well as responses to pulsed sounds.
    With both types of pile driving, it is likely that the onset of 
pile driving could result in temporary, short term changes in an 
animal's typical behavior and/or avoidance of the affected area. These 
behavioral changes may include (Richardson et al., 1995): 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 aggressive 
behavior (such as tail/fluke slapping or jaw clapping); avoidance of 
areas where sound sources are located; and/or flight responses (e.g., 
pinnipeds flushing into water from haul-outs or rookeries). Pinnipeds 
may increase their haul-out time, possibly to avoid in-water 
disturbance (Thorson and Reyff, 2006).
    The biological significance of many of these behavioral 
disturbances is difficult to predict, especially if the detected 
disturbances appear minor. However, the consequences of behavioral 
modification could be expected to be biologically significant if the 
change affects growth, survival, or reproduction. Significant 
behavioral modifications that could potentially

[[Page 44044]]

lead to effects on growth, survival, or reproduction include:
     Drastic changes in diving/surfacing patterns (such as 
those thought to cause beaked whale stranding due to exposure to 
military mid-frequency tactical sonar);
     Habitat abandonment due to loss of desirable acoustic 
environment; and
     Cessation of feeding or social interaction.
    The onset of behavioral disturbance from anthropogenic sound 
depends on both external factors (characteristics of sound sources and 
their paths) and the specific characteristics of the receiving animals 
(hearing, motivation, experience, demography) and is difficult to 
predict (Southall et al., 2007).

Auditory Masking

    Natural and artificial sounds can disrupt behavior by masking, or 
interfering with, a marine mammal's ability to hear other sounds. 
Masking occurs when the receipt of a sound is interfered with by 
another coincident sound at similar frequencies and at similar or 
higher levels. Chronic exposure to excessive, though not high-
intensity, sound could cause masking at particular frequencies for 
marine mammals, which utilize sound for vital biological functions. 
Masking can interfere with detection of acoustic signals such as 
communication calls, echolocation sounds, and environmental sounds 
important to marine mammals. Therefore, under certain circumstances, 
marine mammals whose acoustical sensors or environment are being 
severely masked could also be impaired from maximizing their 
performance fitness in survival and reproduction. If the coincident 
(masking) sound were man-made, it could be potentially harassing if it 
disrupted hearing-related behavior. It is important to distinguish TTS 
and PTS, which persist after the sound exposure, from masking, which 
occurs during the sound exposure. Because masking (without resulting in 
TS) is not associated with abnormal physiological function, it is not 
considered a physiological effect, but rather a potential behavioral 
effect.
    The frequency range of the potentially masking sound is important 
in determining any potential behavioral impacts. Because sound 
generated from in-water pile driving is mostly concentrated at low 
frequency ranges, it may have less effect on high frequency 
echolocation sounds made by porpoises. However, lower frequency man-
made sounds are more likely to affect detection of communication calls 
and other potentially important natural sounds such as surf and prey 
sound. It may also affect communication signals when they occur near 
the sound band and thus reduce the communication space of animals 
(e.g., Clark et al., 2009) and cause increased stress levels (e.g., 
Foote et al., 2004; Holt et al., 2009).
    Masking has the potential to impact species at the population or 
community levels as well as at individual levels. Masking affects both 
senders and receivers of the signals and can potentially have long-term 
chronic effects on marine mammal species and populations. Recent 
research suggests that low frequency ambient sound levels have 
increased by as much as 20 dB (more than three times in terms of SPL) 
in the world's ocean from pre-industrial periods, and that most of 
these increases are from distant shipping (Hildebrand, 2009). All 
anthropogenic sound sources, such as those from vessel traffic, pile 
driving, and dredging activities, contribute to the elevated ambient 
sound levels, thus intensifying masking.
    The most intense underwater sounds in the proposed action are those 
produced by impact pile driving. Given that the energy distribution of 
pile driving covers a broad frequency spectrum, sound from these 
sources would likely be within the audible range of marine mammals 
present in the project area. Impact pile driving activity is relatively 
short-term, with rapid pulses occurring for approximately fifteen 
minutes per pile. The probability for impact pile driving resulting 
from this proposed action masking acoustic signals important to the 
behavior and survival of marine mammal species is likely to be 
negligible. Vibratory pile driving is also relatively short-term, with 
rapid oscillations occurring for approximately one and a half hours per 
pile. It is possible that vibratory pile driving resulting from this 
proposed action may mask acoustic signals important to the behavior and 
survival of marine mammal species, but the short-term duration and 
limited affected area would result in insignificant impacts from 
masking. Any masking event that could possibly rise to Level B 
harassment under the MMPA would occur concurrently within the zones of 
behavioral harassment already estimated for vibratory and impact pile 
driving, and which have already been taken into account in the exposure 
analysis.

Acoustic Effects, Airborne

    Marine mammals that occur in the project area could be exposed to 
airborne sounds associated with pile driving that have the potential to 
cause harassment, depending on their distance from pile driving 
activities. Airborne pile driving sound would have less impact on 
cetaceans than pinnipeds because sound from atmospheric sources does 
not transmit well underwater (Richardson et al., 1995); thus, airborne 
sound would only be an issue for pinnipeds either hauled-out or looking 
with heads above water in the project area. 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 their habitat and move further from the source. Studies by 
Blackwell et al. (2004) and Moulton et al. (2005) indicate a tolerance 
or lack of response to unweighted airborne sounds as high as 112 dB 
peak and 96 dB rms.

Anticipated Effects on Habitat

    The proposed activities associated with both projects at NBKB would 
not result in permanent impacts to habitats used directly by marine 
mammals, such as haul-out sites, but may have potential short-term 
impacts to food sources such as forage fish and salmonids. The proposed 
activities could also affect acoustic habitat (see masking discussion 
above), but this is unlikely given the existing conditions at the 
project site (see previous discussion of acoustic environment under 
Description of Sound Sources above). There are no rookeries or major 
haul-out sites, no known foraging hotspots, or other ocean bottom 
structure of significant biological importance to marine mammals 
present in the marine waters in the vicinity of the project area. 
Therefore, the main impact issue associated with the proposed activity 
would be temporarily elevated sound levels and the associated direct 
effects on marine mammals, as discussed previously in this document. 
The most likely impact to marine mammal habitat occurs from pile 
driving effects on likely marine mammal prey (i.e., fish) near NBKB and 
minor impacts to the immediate substrate during installation and 
removal of piles during the pier maintenance project.

Pile Driving Effects on Potential Prey

    Construction activities would produce both pulsed (i.e., impact 
pile driving) and continuous (i.e., vibratory pile driving) sounds. 
Fish react to sounds which are especially strong and/or intermittent 
low-frequency sounds. Short duration, sharp sounds can cause overt or 
subtle changes in fish behavior and local distribution. Hastings and

[[Page 44045]]

Popper (2005) identified several studies that suggest fish may relocate 
to avoid certain areas of sound energy. Additional studies have 
documented effects of pile driving on fish, although several are based 
on studies in support of large, multiyear bridge construction projects 
(e.g., Scholik and Yan, 2001, 2002; Popper and Hastings, 2009). Sound 
pulses at received levels of 160 dB may cause subtle changes in fish 
behavior. SPLs of 180 dB may cause noticeable changes in behavior 
(Pearson et al., 1992; Skalski et al., 1992). SPLs of sufficient 
strength have been known to cause injury to fish and fish mortality. 
The most likely impact to fish from pile driving activities at the 
project area would be temporary behavioral avoidance of the area. The 
duration of fish avoidance of this area after pile driving stops is 
unknown, but a rapid return to normal recruitment, distribution and 
behavior is anticipated. In general, impacts to marine mammal prey 
species are expected to be minor and temporary due to the short 
timeframe for the project. However, adverse impacts may occur to a few 
species of fish which may still be present in the project area despite 
operating in a reduced work window in an attempt to avoid important 
fish spawning time periods.

Pile Driving Effects on Potential Foraging Habitat

    The area likely impacted by the project is relatively small 
compared to the available habitat in inland waters in the region. 
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 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. The area around NBKB, including the 
adjacent ferry terminal and nearby marinas, is heavily altered with 
significant levels of industrial and recreational activity, and is 
unlikely to harbor significant amounts of forage fish. Thus, any 
impacts to marine mammal habitat are not expected to cause significant 
or long-term consequences for individual marine mammals or their 
populations.

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 such 
activity, and other means of effecting the least practicable impact on 
such species or stock and its habitat, paying particular attention to 
rookeries, mating grounds, and areas of similar significance, and on 
the availability of such species or stock for taking for certain 
subsistence uses. Here we provide a single description of proposed 
mitigation measures, as we propose to require similar measures for both 
the Pier 6 and Pier 4 IHAs. The only differences would be related to 
the difference between impact and vibratory driving, as described 
below. The Pier 4 project does not involve impact driving and measures 
specific to that technique are not relevant for the Pier 4 project. 
Please see Proposed Authorizations, below, for requirements specific to 
each proposed IHA.
    Measurements from similar pile driving events were coupled with 
practical spreading loss to estimate zones of influence (ZOI; see 
Estimated Take by Incidental Harassment); these values were used to 
develop mitigation measures for pile driving activities at NBKB. The 
ZOIs effectively represent the mitigation zone that would be 
established around each pile to prevent Level A harassment to marine 
mammals, while providing estimates of the areas within which Level B 
harassment might occur. In addition to the specific measures described 
later in this section, the Navy would conduct briefings between 
construction supervisors and crews, marine mammal monitoring team, and 
Navy staff prior to the start of all pile driving activity, and when 
new personnel join the work, in order to explain responsibilities, 
communication procedures, marine mammal monitoring protocol, and 
operational procedures.

Monitoring and Shutdown for Pile Driving

    The following measures would apply to the Navy's mitigation through 
shutdown and disturbance zones:
    Shutdown Zone--For all pile driving activities, the Navy will 
establish a shutdown zone intended to contain the area in which SPLs 
equal or exceed the 190 dB rms acoustic injury criteria. The purpose of 
a shutdown zone is to define an area within which shutdown of activity 
would occur upon sighting of a marine mammal (or in anticipation of an 
animal entering the defined area), thus preventing injury of marine 
mammals (as described previously under Potential Effects of the 
Specified Activity on Marine Mammals, serious injury or death are 
unlikely outcomes even in the absence of mitigation measures). Modeled 
radial distances for shutdown zones are shown in Table 5. However, a 
minimum shutdown zone of 10 m (which is larger than the maximum 
predicted injury zone) will be established during all pile driving 
activities, regardless of the estimated zone. Vibratory pile driving 
activities are not predicted to produce sound exceeding the 190-dB 
Level A harassment threshold, but these precautionary measures are 
intended to prevent the already unlikely possibility of physical 
interaction with construction equipment and to further reduce any 
possibility of acoustic injury.
    Disturbance Zone--Disturbance zones are the areas in which SPLs 
equal or exceed 160 and 120 dB rms (for impulse and continuous sound, 
respectively). Disturbance zones provide utility for monitoring 
conducted for mitigation purposes (i.e., shutdown zone monitoring) by 
establishing monitoring protocols for areas adjacent to the shutdown 
zones. Monitoring of disturbance zones enables observers to be aware of 
and communicate the presence of marine mammals in the project area but 
outside the shutdown zone and thus prepare for potential shutdowns of 
activity. However, the primary purpose of disturbance zone monitoring 
is for documenting incidents of Level B harassment; disturbance zone 
monitoring is discussed in greater detail later (see Proposed 
Monitoring and Reporting). Nominal radial distances for disturbance 
zones are shown in Table 5.
    In order to document observed incidents of harassment, monitors 
record all marine mammal observations, regardless of location. The 
observer's location, as well as the location of the pile being driven, 
is known from a GPS. The location of the animal is estimated as a 
distance from the observer, which is then compared to the location from 
the pile. It may then be estimated whether the animal was exposed to 
sound levels constituting incidental harassment on the basis of 
predicted distances to relevant thresholds in post-processing of 
observational and acoustic data, and a precise accounting of observed 
incidences of harassment created. This information may then be used to 
extrapolate observed takes to reach an approximate understanding of 
actual total takes.

[[Page 44046]]

    Monitoring Protocols--Monitoring would be conducted before, during, 
and after pile driving activities. In addition, observers shall record 
all incidents of marine mammal occurrence, regardless of distance from 
activity, and shall document any behavioral reactions in concert with 
distance from piles being driven. Observations made outside the 
shutdown zone will not result in shutdown; that pile segment would be 
completed without cessation, unless the animal approaches or enters the 
shutdown zone, at which point all pile driving activities would be 
halted. Monitoring will take place from fifteen minutes prior to 
initiation through thirty minutes post-completion of pile driving 
activities. 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 equipment is no more than thirty 
minutes. Please see the project-specific Monitoring Plans (Appendix C 
in both the Pier 4 and Pier 6 applications; www.nmfs.noaa.gov/pr/permits/incidental/construction.htm), developed by the Navy in 
agreement with NMFS, for full details of the monitoring protocols.
    The following additional measures apply to visual monitoring:
    (1) Monitoring will be conducted by qualified observers, who will 
be placed at the best vantage point(s) practicable to monitor for 
marine mammals and implement shutdown/delay procedures when applicable 
by calling for the shutdown to the hammer operator. Qualified observers 
are trained biologists, with the following minimum qualifications:
     Visual acuity in both eyes (correction is permissible) 
sufficient for discernment of moving targets at the water's surface 
with ability to estimate target size and distance; use of binoculars 
may be necessary to correctly identify the target;
     Advanced education in biological science or related field 
(undergraduate degree or higher required);
     Experience and ability to conduct field observations and 
collect data according to assigned protocols (this may include academic 
experience);
     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 and times when in-water construction 
activities were suspended to avoid potential incidental injury from 
construction sound of marine mammals observed within a defined shutdown 
zone; and marine mammal behavior; and
     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.
    (2) Prior to the start of pile driving activity, the shutdown zone 
will be monitored for fifteen minutes to ensure that it is clear of 
marine mammals. Pile driving will only commence once observers have 
declared the shutdown zone clear of marine mammals; animals will be 
allowed to remain in the shutdown zone (i.e., must leave of their own 
volition) and their behavior will be monitored and documented. The 
shutdown zone may only be declared clear, and pile driving started, 
when the entire shutdown zone is visible (i.e., when not obscured by 
dark, rain, fog, etc.). In addition, if such conditions should arise 
during impact pile driving that is already underway, the activity would 
be halted.
    (3) If a marine mammal approaches or enters the shutdown zone 
during the course of pile driving operations, activity will be halted 
and delayed until either the animal has voluntarily left and been 
visually confirmed beyond the shutdown zone or fifteen minutes have 
passed without re-detection of the animal. Monitoring will be conducted 
throughout the time required to drive a pile.

Special Conditions

    The Navy has not requested the authorization of incidental take for 
killer whales or gray whales (see discussion below in Estimated Take by 
Incidental Harassment). Therefore, shutdown would be implemented in the 
event that either of these species is observed in the vicinity, prior 
to entering the defined disturbance zone. As described later in this 
document, we believe that occurrence of these species during the in-
water work window would be uncommon and that the occurrence of an 
individual or group would likely be highly noticeable and would attract 
significant attention in local media and with local whale watchers and 
interested citizens.
    Prior to the start of pile driving on any day, the Navy would 
contact and/or review the latest sightings data from the Orca Network 
and/or Center for Whale Research to determine the location of the 
nearest marine mammal sightings. The Orca Sightings Network consists of 
a list of over 600 residents, scientists, and government agency 
personnel in the U.S. and Canada, and includes passive acoustic 
detections. The presence of a killer whale or gray whale in the 
southern reaches of Puget Sound would be a notable event, drawing 
public attention and media scrutiny. With this level of coordination in 
the region of activity, the Navy should be able to effectively receive 
real-time information on the presence or absence of whales, sufficient 
to inform the day's activities. Pile driving would not occur if there 
was the risk of incidental harassment of a species for which incidental 
take was not authorized.
    During vibratory pile driving, one land-based observer would be 
positioned at the pier work site. Additionally, one vessel-based 
observer will travel through the monitoring area, completing an entire 
loop approximately every thirty minutes (please see Figure 1 of 
Appendix C in the Navy's applications). If any killer whales or gray 
whales are detected, activity would not begin or would shut down.

Timing Restrictions

    In the project area, designated timing restrictions exist to avoid 
in-water work when salmonids and other spawning forage fish are likely 
to be present. The in-water work window is June 15-March 1 for Pier 6 
and July 16-February 15 for Pier 4. All in-water construction 
activities would occur only during daylight hours (sunrise to sunset).

Soft Start

    The use of a soft start procedure is believed to provide additional 
protection to marine mammals by warning or providing a chance to leave 
the area prior to the hammer operating at full capacity, and typically 
involves a requirement to initiate sound from the hammer at reduced 
energy followed by a waiting period. This procedure is repeated two 
additional times. It is difficult to specify the reduction in energy 
for any given hammer because of variation across drivers and, for 
impact hammers, the actual number of strikes at reduced energy will 
vary because operating the hammer at less than full power results in 
``bouncing'' of the hammer as it strikes the pile, resulting in 
multiple ``strikes.'' The pier maintenance project will utilize soft 
start techniques for both impact and vibratory pile driving. We require 
the Navy to initiate sound from vibratory hammers for fifteen seconds 
at reduced energy followed by a thirty-second

[[Page 44047]]

waiting period, with the procedure repeated two additional times. For 
impact driving, we require an initial set of three strikes from the 
impact hammer at reduced energy, followed by a thirty-second waiting 
period, then two subsequent three strike sets. Soft start will be 
required at the beginning of each day's pile driving work and at any 
time following a cessation of pile driving of thirty minutes or longer.
    We have carefully evaluated the Navy's proposed mitigation measures 
and considered their effectiveness in past implementation to 
preliminarily determine whether they are likely to effect the least 
practicable impact on the affected marine mammal species and stocks and 
their habitat. Our evaluation of potential measures included 
consideration of the following factors in relation to one another: (1) 
The manner in which, and the degree to which, the successful 
implementation of the measure is expected to minimize adverse impacts 
to marine mammals, (2) the proven or likely efficacy of the specific 
measure to minimize adverse impacts as planned; and (3) the 
practicability of the measure for applicant implementation.
    Any mitigation measure(s) we prescribe should be able to 
accomplish, have a reasonable likelihood of accomplishing (based on 
current science), or contribute to the accomplishment of one or more of 
the general goals listed below:
    (1) Avoidance or minimization of injury or death of marine mammals 
wherever possible (goals 2, 3, and 4 may contribute to this goal).
    (2) A reduction in the number (total number or number at 
biologically important time or location) of individual marine mammals 
exposed to stimuli expected to result in incidental take (this goal may 
contribute to 1, above, or to reducing takes by behavioral harassment 
only).
    (3) A reduction in the number (total number or number at 
biologically important time or location) of times any individual marine 
mammal would be exposed to stimuli expected to result in incidental 
take (this goal may contribute to 1, above, or to reducing takes by 
behavioral harassment only).
    (4) A reduction in the intensity of exposure to stimuli expected to 
result in incidental take (this goal may contribute to 1, above, or to 
reducing the severity of behavioral harassment only).
    (5) Avoidance or minimization of adverse effects to marine mammal 
habitat, paying particular attention to the prey base, blockage or 
limitation of passage to or from biologically important areas, 
permanent destruction of habitat, or temporary disturbance of habitat 
during a biologically important time.
    (6) For monitoring directly related to mitigation, an increase in 
the probability of detecting marine mammals, thus allowing for more 
effective implementation of the mitigation.
    Based on our evaluation of the Navy's proposed measures, as well as 
any other potential measures that may be relevant to the specified 
activity, we have preliminarily determined that the proposed mitigation 
measures provide the means of effecting the least practicable impact on 
marine mammal 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 
incidental take 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.
    Any monitoring requirement we prescribe should improve our 
understanding of one or more of the following:
     Occurrence of marine mammal species in action area (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 responses to acute stressors, or impacts of 
chronic exposures (behavioral or physiological).
     How anticipated responses to stressors impact either: (1) 
Long-term fitness and survival of an individual; or (2) Population, 
species, or stock.
     Effects on marine mammal habitat and resultant impacts to 
marine mammals.
     Mitigation and monitoring effectiveness.
    With the exception of acoustic monitoring required for the Pier 6 
project (see below), monitoring requirements are the same for both Pier 
4 and Pier 6 projects, and a single discussion is provided here. 
Monitoring requirements specific to impact pile driving are only 
applicable to the Pier 6 project. The Navy marine mammal monitoring 
plans can be found as Appendix C of both applications, on the Internet 
at www.nmfs.noaa.gov/pr/permits/incidental/construction.htm.

Acoustic Monitoring

    Specific to the Pier 6 project, the Navy will implement a sound 
source level verification study during the specified activities. Data 
will be collected in order to estimate airborne and underwater source 
levels for vibratory removal of timber piles and impact driving of 
concrete piles, with measurements conducted for ten piles of each type. 
Monitoring will include one underwater and one airborne monitoring 
position. These exact positions will be determined in the field during 
consultation with Navy personnel, subject to constraints related to 
logistics and security requirements. Reporting of measured sound level 
signals will include the average, minimum, and maximum rms value and 
frequency spectra for each pile monitored. Please see section 11.4.4 of 
the Navy's Pier 6 application for details of the Navy's acoustic 
monitoring plan. This acoustic monitoring program was included with 
requirements under Year 2 of the Pier 6 project, but could not be 
conducted due to changes to the project schedule.

Visual Marine Mammal Observations

    The Navy will collect sighting data and behavioral responses to 
construction for marine mammal species observed in the region of 
activity during the period of activity. All observers will be trained 
in marine mammal identification and behaviors and are required to have 
no other construction-related tasks while conducting monitoring. The 
Navy will monitor the shutdown zone and disturbance zone before, 
during, and after pile driving, with observers located at the best 
practicable vantage points. Based on our requirements, the Navy would 
implement the following procedures for pile driving:
     MMOs would be located at the best vantage point(s) in 
order to properly see the entire shutdown zone and as much of the 
disturbance zone as possible.
     During all observation periods, observers will use 
binoculars and the

[[Page 44048]]

naked eye to search continuously for marine mammals.
     If the shutdown zones are obscured by fog or poor lighting 
conditions, pile driving at that location will not be initiated until 
that zone is visible. Should such conditions arise while impact driving 
is underway, the activity would be halted.
     The shutdown and disturbance zones around the pile will be 
monitored for the presence of marine mammals before, during, and after 
any pile driving or removal activity.
    During vibratory pile driving, two observers would be deployed as 
described under Proposed Mitigation, including one land-based observer 
and one-vessel-based observer traversing the extent of the Level B 
harassment zone. We previously required (for Years 1-2 of the Pier 6 
project) the deployment of four land-based observers (in addition to 
one vessel-based observer) during vibratory driving. This additional 
monitoring effort served to confirm that our assumptions relating to 
marine mammal occurrence in the action area were accurate, and we do 
not believe it necessary to continue with two shore-based observers in 
the far-field, in addition to the far-field vessel-based observer, to 
accomplish the required monitoring of incidental take. During impact 
driving, one observer would be positioned at or near the pile to 
observe the much smaller disturbance zone.
    Individuals implementing the monitoring protocol will assess its 
effectiveness using an adaptive approach. Monitoring biologists will 
use their best professional judgment throughout implementation and seek 
improvements to these methods when deemed appropriate. Any 
modifications to protocol will be coordinated between NMFS and the 
Navy.

Data Collection

    We require that observers use approved data forms. Among other 
pieces of information, the Navy will record detailed information about 
any implementation of shutdowns, including the distance of animals to 
the pile and description of specific actions that ensued and resulting 
behavior of the animal, if any. In addition, the Navy will attempt to 
distinguish between the number of individual animals taken and the 
number of incidents of take. We require that, at a minimum, the 
following information be collected on the sighting forms:
     Date and time that monitored activity begins or ends;
     Construction activities occurring during each observation 
period;
     Weather parameters (e.g., percent cover, visibility);
     Water conditions (e.g., sea state, tide state);
     Species, numbers, and, if possible, sex and age class of 
marine mammals;
     Description of any observable marine mammal behavior 
patterns, including bearing and direction of travel and distance from 
pile driving activity;
     Distance from pile driving activities to marine mammals 
and distance from the marine mammals to the observation point;
     Description of implementation of mitigation measures 
(e.g., shutdown or delay).
     Locations of all marine mammal observations; and
     Other human activity in the area.

Reporting

    A draft report would be submitted to NMFS within 45 days of the 
completion of marine mammal monitoring, or sixty days prior to the 
issuance of any subsequent IHA for these projects (if required), 
whichever comes first. The report will include marine mammal 
observations pre-activity, during-activity, and post-activity during 
pile driving days, and will also provide descriptions of any behavioral 
responses to construction activities by marine mammals and a complete 
description of all mitigation shutdowns and the results of those 
actions and an extrapolated total take estimate based on the number of 
marine mammals observed during the course of construction. A final 
report must be submitted within thirty days following resolution of 
comments on the draft report.

Monitoring Results From Previously Authorized Activities

    The Navy complied with the mitigation and monitoring required under 
the previous authorizations for the Pier 6 project. Marine mammal 
monitoring occurred before, during, and after each pile driving event. 
During the course of these activities, the Navy did not exceed the take 
levels authorized under the IHAs. In accordance with the 2013 and 2014 
IHAs, the Navy submitted monitoring reports (available at: 
www.nmfs.noaa.gov/pr/permits/incidental/construction.htm).
    Under the 2013 IHA, the Navy anticipated a total of 65 pile driving 
days; however, only a limited program of test pile driving actually 
took place. Pile driving occurred on only two days, with a total of 
only two piles driven (both impact-driven concrete piles). The only 
species observed was the California sea lion. A total of 24 individuals 
were observed within the defined Level B harassment zone, but all were 
hauled-out on port security barrier floats outside of the defined Level 
B harassment zone for airborne sound. Therefore, no take of marine 
mammals occurred incidental to project activity under the year one IHA.
    Under the 2014 IHA, the Navy anticipated a total of sixty pile 
driving days, but actually conducted a total of 32 pile driving days. 
This total included sixteen days each of impact driving and pile 
removal; however, only approximately fifty percent of pile removal 
required use of the vibratory driver and there were a total of 24 
monitoring days. Only two species, the California sea lion and harbor 
seal, were observed. Total observed incidents of take were 275 for 
California sea lions (151 during vibratory removal and 124 during 
impact driving) and ten for harbor seals (nine during vibratory removal 
and one during impact driving). Given the extensive far-field 
monitoring required, no extrapolation of observed takes to unobserved 
area was necessary.
    Observed behaviors were typical for pinnipeds and included 
foraging, milling, and traveling. Numerous California sea lions use the 
port security floats as a haul-out. No reactions indicative of 
disturbance were observed.

Estimated Take by Incidental Harassment

    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].''
    All anticipated takes would be by Level B harassment resulting from 
vibratory and impact pile driving and involving temporary changes in 
behavior. The proposed mitigation and monitoring measures are expected 
to minimize the possibility of injurious or lethal takes such that take 
by Level A harassment, serious injury, or mortality is considered 
discountable. However, it is unlikely that injurious or lethal takes 
would occur even in the absence of the planned mitigation and 
monitoring measures.
    If a marine mammal responds to a stimulus by changing its behavior 
(e.g., through relatively minor changes in locomotion direction/speed 
or

[[Page 44049]]

vocalization behavior), the response may or may not constitute taking 
at the individual level, and is unlikely to affect the stock or the 
species as a whole. However, if a sound source displaces marine mammals 
from an important feeding or breeding area for a prolonged period, 
impacts on animals or on the stock or species could potentially be 
significant (e.g., Lusseau and Bejder, 2007; Weilgart, 2007). Given the 
many uncertainties in predicting the quantity and types of impacts of 
sound on marine mammals, it is common practice to estimate how many 
animals are likely to be present within a particular distance of a 
given activity, or exposed to a particular level of sound. In practice, 
depending on the amount of information available to characterize daily 
and seasonal movement and distribution of affected marine mammals, it 
can be difficult to distinguish between the number of individuals 
harassed and the instances of harassment and, when duration of the 
activity is considered, it can result in a take estimate that 
overestimates the number of individuals harassed. In particular, for 
stationary activities, it is more likely that some smaller number of 
individuals may accrue a number of incidences of harassment per 
individual than for each incidence to accrue to a new individual, 
especially if those individuals display some degree of residency or 
site fidelity and the impetus to use the site (e.g., because of 
foraging opportunities) is stronger than the deterrence presented by 
the harassing activity.
    The project area is not believed to be particularly important 
habitat for marine mammals, nor is it considered an area frequented by 
marine mammals, although harbor seals may be present year-round and sea 
lions are known to haul-out on man-made objects at the NBKB waterfront. 
Sightings of other species are rare. Therefore, behavioral disturbances 
that could result from anthropogenic sound associated with these 
activities are expected to affect only a relatively small number of 
individual marine mammals, although those effects could be recurring 
over the life of the project if the same individuals remain in the 
project vicinity.
    The Navy has requested authorization for the incidental taking of 
small numbers of Steller sea lions, California sea lions, and harbor 
seals in Sinclair Inlet and nearby waters that may result from pile 
driving during construction activities associated with the pier 
maintenance projects described previously in this document. The 
available information, and the most appropriate way to use that 
information in estimating take by incidental harassment, is general to 
Sinclair Inlet. Therefore, we provide a single discussion of exposure 
analyses that is applicable to both the Pier 4 and Pier 6 projects.
    In order to estimate the potential incidents of take that may occur 
incidental to the specified activity, we must first estimate the extent 
of the sound field that may be produced by the activity and then 
consider in combination with information about marine mammal density or 
abundance in the project area. We first provide information on 
applicable sound thresholds for determining effects to marine mammals 
before describing the information used in estimating the sound fields, 
the available marine mammal density or abundance information, and the 
method of estimating potential incidents of take.

Sound Thresholds

    We use generic sound exposure thresholds to determine when an 
activity that produces sound might result in impacts to a marine mammal 
such that a take by harassment might occur. To date, no studies have 
been conducted that explicitly examine impacts to marine mammals from 
pile driving sounds or from which empirical sound thresholds have been 
established. These thresholds (Table 3) are used to estimate when 
harassment may occur (i.e., when an animal is exposed to levels equal 
to or exceeding the relevant criterion) in specific contexts; however, 
useful contextual information that may inform our assessment of effects 
is typically lacking and we consider these thresholds as step 
functions. NMFS is working to revise these acoustic guidelines; for 
more information on that process, please visit www.nmfs.noaa.gov/pr/acoustics/guidelines.htm.

               Table 3--Current Acoustic Exposure Criteria
------------------------------------------------------------------------
            Criterion                 Definition           Threshold
------------------------------------------------------------------------
Level A.........................  Injury (PTS--any    180 dB (cetaceans)/
harassment (underwater).........   level above that    190 dB
                                   which is known to   (pinnipeds)
                                   cause TTS).         (rms).
Level B harassment (underwater).  Behavioral          160 dB (impulsive
                                   disruption.         source)/120 dB
                                                       (continuous
                                                       source) (rms).
Level B harassment (airborne)...  Behavioral          90 dB (harbor
                                   disruption.         seals)/100 dB
                                                       (other pinnipeds)
                                                       (unweighted).
------------------------------------------------------------------------

Distance to Sound Thresholds

    Underwater Sound Propagation Formula--Pile driving generates 
underwater noise that can potentially result in disturbance to marine 
mammals in the project area. 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
R1 = the distance of the modeled SPL from the driven 
pile, and
R2 = the distance from the driven pile of the initial 
measurement.

    This formula neglects loss due to scattering and absorption, which 
is assumed to be zero here. The degree to which underwater sound 
propagates away from a sound source is dependent on a variety of 
factors, most notably the water bathymetry and presence or absence of 
reflective or absorptive conditions including in-water structures and 
sediments. Spherical spreading occurs in a perfectly unobstructed 
(free-field) environment not limited by depth or water surface, 
resulting in a 6 dB reduction in sound level for each doubling of 
distance from the source (20*log[range]). Cylindrical spreading occurs 
in an environment in which sound propagation is bounded by the water 
surface and sea bottom, resulting in a reduction of 3 dB in sound level 
for each doubling of distance from the source (10*log[range]). A 
practical spreading value of fifteen is often used under conditions, 
such as Sinclair Inlet, where water increases with depth as the 
receiver moves away from the shoreline,

[[Page 44050]]

resulting in an expected propagation environment that would lie between 
spherical and cylindrical spreading loss conditions. Practical 
spreading loss (4.5 dB reduction in sound level for each doubling of 
distance) is assumed here.
    Underwater Sound--The intensity of pile driving sounds is greatly 
influenced by factors such as the type of piles, hammers, and the 
physical environment in which the activity takes place. However, a 
limited quantity of literature is available for consideration regarding 
SPLs recorded from pile driving projects similar to the Navy's activity 
(i.e., impact-driven concrete piles and vibratory pile removal). In 
order to determine reasonable SPLs and their associated effects on 
marine mammals that are likely to result from pile driving at NBKB, 
studies with similar properties to the specified activity were 
evaluated, and are displayed in Table 4.

                               Table 4--Summary of Proxy Measured Underwater SPLs
----------------------------------------------------------------------------------------------------------------
                                                                 Pile size and
              Location                       Method                 material                Measured SPLs
----------------------------------------------------------------------------------------------------------------
Berth 22, Port of Oakland \1\......  Impact................  24-in concrete.......  176 dB at 10 m.
Mad River Slough, CA \1\...........  Vibratory.............  13-in steel pipe.....  155 dB at 10 m.
Port Townsend, WA \2\..............  Vibratory (removal)...  12-in timber.........  150 dB at 16 m.
----------------------------------------------------------------------------------------------------------------
Sources: \1\ Caltrans, 2012; \2\ Laughlin, 2011.

    We consider the values presented in Table 4 to be representative of 
SPLs that may be produced by impact driving of concrete piles, 
vibratory driving of steel piles, and vibratory removal of timber 
piles, respectively. The value from Berth 22 was selected as 
representative of the largest concrete pile size to be installed and 
may be conservative when smaller concrete piles are driven. The value 
from Mad River Slough is for vibratory installation and would likely be 
conservative when applied to vibratory extraction, which would be 
expected to produce lower SPLs than vibratory installation of same-
sized piles. All calculated distances to and the total area encompassed 
by the marine mammal sound thresholds are provided in Table 5.

             Table 5--Distances to Relevant Sound Thresholds and Areas of Ensonification, Underwater
----------------------------------------------------------------------------------------------------------------
                                        Distance to threshold (m) and associated area of ensonification (km\2\)
             Description             ---------------------------------------------------------------------------
                                            190 dB             180 dB             160 dB             120 dB
----------------------------------------------------------------------------------------------------------------
Concrete piles, impact..............       1.2, <0.0001        5.4, 0.0001          117, 0.04                n/a
Steel piles, vibratory..............                  0                  0                n/a      2,154\2\, 7.5
Timber piles, vibratory.............                  0                  0                n/a         1,585; 5.0
----------------------------------------------------------------------------------------------------------------
\1\ SPLs used for calculations were: 191 dB for impact driving, 170 dB for vibratory removal of steel piles, and
  168 dB for vibratory removal of timber piles.
\2\ Areas presented take into account attenuation and/or shadowing by land. Please see Appendix B in the Navy's
  applications.

    Sinclair Inlet does not represent open water, or free field, 
conditions. Therefore, sounds would attenuate according to the 
shoreline topography. Distances shown in Table 5 are estimated for 
free-field conditions, but areas are calculated per the actual 
conditions of the action area. See Appendix B of the Navy's 
applications for a depiction of areas in which each underwater sound 
threshold is predicted to occur at the project area due to pile 
driving.
    Airborne Sound--Pile driving can generate airborne sound that could 
potentially result in disturbance to marine mammals (specifically, 
pinnipeds) which are hauled out or at the water's surface. As was 
discussed for underwater sound from pile driving, the intensity of pile 
driving sounds is greatly influenced by factors such as the type of 
piles, hammers, and the physical environment in which the activity 
takes place. As before, measured values from other studies were used as 
proxy values to determine reasonable airborne SPLs and their associated 
effects on marine mammals that might result from pile driving at NBKB. 
There are no measurements known for unweighted airborne sound from 
either impact driving of concrete piles or for vibratory driving of 
timber piles. A spherical spreading loss model (i.e., 6 dB reduction in 
sound level for each doubling of distance from the source), in which 
there is a perfectly unobstructed (free-field) environment not limited 
by depth or water surface, is appropriate for use with airborne sound 
and was used to estimate the distance to the airborne thresholds.

                                Table 6--Summary of Proxy Measured Airborne SPLs
----------------------------------------------------------------------------------------------------------------
                                                               Pile size and
             Location                       Method                material                 Measured SPLs
----------------------------------------------------------------------------------------------------------------
Test Pile Program, Hood Canal \1\.  Impact...............  24-in steel pipe.....  89 dB at 15 m.
Wahkiakum Ferry Terminal, WA \2\..  Vibratory............  18-in steel pipe.....  87.5 dB at 15 m.
----------------------------------------------------------------------------------------------------------------
Sources: \1\ Illingworth & Rodkin, 2012; \2\ Laughlin, 2010.

    Steel piles generally produce louder source levels than do 
similarly sized concrete or timber piles. Similarly, the value shown 
here for the larger steel piles (18-in) would likely be louder than 
smaller steel piles or timber piles. Therefore, these values will 
likely overestimate the distances to relevant thresholds. Based on 
these values and the assumption of spherical spreading loss, distances 
to relevant thresholds and associated areas of ensonification

[[Page 44051]]

are presented in Table 7; these areas are depicted in Appendix B of the 
Navy's applications.

      Table 7--Distances to Relevant Sound Thresholds and Areas of
                        Ensonification, Airborne
------------------------------------------------------------------------
                                           Distance to threshold (m) and
                                                associated area of
                                               ensonification (m\2\)
                  Group                  -------------------------------
                                                             Vibratory
                                          Impact driving      driving
------------------------------------------------------------------------
Harbor seals............................         13, 169         11, 121
Sea lions...............................           5, 25           4, 16
------------------------------------------------------------------------
\1\SPLs used for calculations were: 112.5 dB for impact driving and 111
  dB for use of a vibratory hammer.

    However, because there are no regular haul-outs within such a small 
area around the site of proposed pile driving activity, we believe that 
incidents of incidental take resulting solely from airborne sound are 
unlikely. In particular, the zones for sea lions are within the minimum 
shutdown zone defined for underwater sound, and the zones for harbor 
seals are only slightly larger. It is extremely unlikely that any 
structure would be available as a haul-out opportunity within these 
zones, or that an animal would haul out in such close proximity to pile 
driving activity. There is a remote possibility that an animal could 
surface in-water, but with head out, within one of the defined zones 
and thereby be exposed to levels of airborne sound that we associate 
with harassment, but any such occurrence would likely be accounted for 
in our estimation of incidental take from underwater sound.
    In summary, we generally recognize that pinnipeds occurring within 
an estimated airborne harassment zone, whether in the water or hauled 
out, could be exposed to airborne sound that may result in behavioral 
harassment. However, any animal exposed to airborne sound above the 
behavioral harassment threshold is likely to also be exposed to 
underwater sound above relevant thresholds (which are typically in all 
cases larger zones than those associated with airborne sound). Thus, 
the behavioral harassment of these animals is already accounted for in 
these estimates of potential take. Multiple incidents of exposure to 
sound above NMFS' thresholds for behavioral harassment are not believed 
to result in increased behavioral disturbance, in either nature or 
intensity of disturbance reaction. 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 Densities

    For all species, the best scientific information available was 
considered for use in the marine mammal take assessment calculations. 
The Navy has developed, with input from regional marine mammal experts, 
estimates of marine mammal densities in Washington inland waters for 
the Navy Marine Species Density Database (NMSDD). A technical report 
(Hanser et al., 2015) describes methodologies and available information 
used to derive these densities, which are generally based upon the best 
available information for Washington inland waters, except where 
specific local abundance information is available.
    At NBKB, the Navy began collecting opportunistic observational data 
of animals hauled-out on the floating security barrier. These surveys 
began in February 2010 and have been conducted approximately monthly 
from September 2010 through December 2014 (DoN, 2014). In addition, the 
Washington State Department of Transportation (WSDOT) recently 
conducted in-water pile driving over the course of multiple work 
windows as part of the Manette Bridge construction project in the 
nearby Port Washington Narrows. WSDOT conducted required marine mammal 
monitoring as part of this project (WSDOT, 2011, 2012; Rand, 2011). 
Here, we considered NMSDD density information for all five species we 
believe to have the potential for occurrence in the project area, but 
determined it most appropriate to use local abundance data for the 
three pinniped species. Density information is shown in Table 8; see 
Hanser et al. (2015) for descriptions of how the densities were 
derived. That document is publicly available on the Internet at 
nwtteis.com/DocumentsandReferences/NWTTDocuments/SupportingTechnicalDocuments.aspx (accessed July 13, 2015). See below 
for discussion of gray whale and killer whale.

Description of Take Calculation

    The following assumptions are made when estimating potential 
incidences of take:
     All marine mammal individuals potentially available are 
assumed to be present within the relevant area, and thus incidentally 
taken;
     An individual can only be taken once during a 24-h period;
     There were will be sixty total days of activity for the 
Pier 6 project and thirty total days for the Pier 4 project; and,
     Exposures to sound levels at or above the relevant 
thresholds equate to take, as defined by the MMPA.
    The estimation of marine mammal takes typically uses the following 
calculation:

Exposure estimate = (n * ZOI) * days of total activity

Where:
n = density estimate used for each species/season.
ZOI = sound threshold ZOI area; the area encompassed by all 
locations where the SPLs equal or exceed the threshold being 
evaluated.
n * ZOI produces an estimate of the abundance of animals that could 
be present in the area for exposure, and is rounded to the nearest 
whole number before multiplying by days of total activity.

    The ZOI impact area is estimated using the relevant distances in 
Table 5, taking into consideration the possible affected area due to 
topographical constraints of the action area (i.e., radial distances to 
thresholds are not always reached). When local abundance is the best 
available information, in lieu of the density-area method described 
above, we may simply multiply some number of animals (as determined 
through counts of animals hauled-out) by the number of days of 
activity, under the assumption that all of those animals will be 
present and incidentally taken on each day of activity.
    There are a number of reasons why estimates of potential incidents 
of take may be conservative, assuming that available density or 
abundance estimates and estimated ZOI areas are accurate. We assume, in 
the absence of information supporting a more refined conclusion, that 
the output of the calculation represents the number of individuals that 
may be taken by the specified activity. In fact, in the context of 
stationary activities such as pile driving and in areas where resident 
animals may be present, this number more realistically represents the 
number of incidents of take that may accrue to a smaller number of 
individuals. While pile driving can occur any day throughout the in-
water work window, and the analysis is conducted on a per day basis, 
only a fraction of that time (typically a matter of hours on any given 
day) is actually spent pile driving. The potential effectiveness of 
mitigation measures in reducing the number of takes is typically not 
quantified in the take estimation process. For these reasons, these 
take estimates may be conservative. See Table 8 for total estimated 
incidents of take.

[[Page 44052]]

    Harbor Seal--While no harbor seal haul-outs are present in the 
action area or in the immediate vicinity of NBKB, haul-outs are present 
elsewhere in Sinclair Inlet and in other nearby waters and harbor seals 
may haul out on available objects opportunistically. Marine mammal 
monitoring conducted during pile driving work on the Manette Bridge 
showed variable numbers of harbor seals (but generally greater than 
indicated by the uncorrected NMSDD density of 1.219 animals/km\2\). 
During the first year of construction (in-water work window only), an 
average of 3.7 harbor seals were observed per day of monitoring with a 
maximum of 59 observed in October 2011 (WSDOT, 2011; Rand, 2011). 
During the most recent construction period (July-November 2012), an 
average of eleven harbor seals per monitoring day was observed, though 
some animals were likely counted multiple times (WSDOT, 2012). Given 
the potential for similar occurrence of harbor seals in the vicinity of 
NBKB during the in-water construction period, we determined it 
appropriate to use this most recent, local abundance information in the 
take assessment calculation.
    California Sea Lion--Similar to harbor seals, it is not likely that 
use of the NMSDD density value for California sea lions (0.13 animals/
km\2\) would adequately represent their potential occurrence in the 
project area, i.e., would result in an underestimate. California sea 
lions are commonly observed hauled out on the floating security barrier 
which is in close proximity to the piers; counts from 52 surveys 
(February 2010-December 2014) showed an average of 48 individuals per 
survey day (range 0-219; DoN, 2014). These counts represent the best 
local abundance data available and were used in the take assessment 
calculation.
    Steller Sea Lion--No Steller sea lion haul-outs are present within 
or near the action area, and Steller sea lions have not been observed 
during Navy waterfront surveys or during monitoring associated with the 
Manette Bridge construction project. It is assumed that the possibility 
exists that a Steller sea lion could occur in the project area, but 
there is no known attractant in Sinclair Inlet, which is a relatively 
muddy, industrialized area, and the floating security barrier that 
California sea lions use as an opportunistic haul-out cannot generally 
accommodate the larger adult Steller sea lions (juveniles could haul-
out on the barrier). Use of the NMSDD density estimate (0.037 animals/
km\2\) results in an estimate of zero exposures, and there are no 
existing data to indicate that Steller sea lions would occur more 
frequently locally. However, as a precaution and to account for the 
possibility that a Steller sea lion could occur in the project area, we 
assume that one Steller sea lion could occur per day of activity.
    Killer Whale--Transient killer whales are rarely observed in the 
project area, with records since 2002 showing one group transiting 
through the area in May 2004 and a subsequent, similar observation in 
May 2010. No other observations have occurred during Navy surveys or 
during project monitoring for Manette Bridge. Use of the NMSDD density 
estimate (0.0024 animals/km\2\) results in an estimate of zero 
exposures, and there are no existing data to indicate that killer 
whales would occur more frequently locally. Therefore, the Navy has not 
requested the authorization of incidental take for transient killer 
whales and we do not propose such authorization. The Navy would not 
begin activity or would shut down upon report of a killer whale present 
within or approaching the relevant ZOI.
    Gray Whale--Gray whales are rarely observed in the project area, 
and the majority of in-water work would occur when whales are 
relatively less likely to occur (i.e., outside of March-May). Since 
2002 and during the in-water work window, there are observational 
records of three whales (all during winter 2008-09) and a stranding 
record of a fourth whale (January 2013). No other observations have 
occurred during Navy surveys or during project monitoring for Manette 
Bridge. Use of the NMSDD density estimate (0.0005 animals/km\2\) 
results in an estimate of zero exposures, and there are no existing 
data to indicate that gray whales would occur more frequently locally. 
Therefore, the Navy has not requested the authorization of incidental 
take for gray whales and we do not propose such authorization. The Navy 
would not begin activity or would shut down upon report of a gray whale 
present within or approaching the relevant ZOI.

                                                  Table 8--Calculations for Incidental Take Estimation
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                      Total proposed     Total proposed
                                                                                   n * ZOI                          authorized takes,  authorized takes,
                   Species                         n (animals/km\2\) \1\       (vibratory steel    Abundance \3\       Pier 6 (% of       Pier 4 (% of
                                                                              pile removal) \2\                        total stock)       total stock)
--------------------------------------------------------------------------------------------------------------------------------------------------------
California sea lion.........................  0.1266........................                  1                 45        2,880 (1.0)        1,440 (0.5)
Steller sea lion............................  0.0368........................                  0                  1           60 (0.1)          30 (0.05)
Harbor seal.................................  1.219 \5\.....................                  9                 11          660 (6.0)          330 (3.0)
Killer whale (transient)....................  0.0024 (fall).................                  0                n/a                  0                  0
Gray whale..................................  0.0005 (winter)...............                  0                n/a                  0                  0
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Best available species- and season-specific density estimate, with season noted in parentheses where applicable (Hanser et al., 2015).
\2\ Product of density and largest ZOI (7.5 km\2\) rounded to nearest whole number; presented for reference only.
\3\ Best abundance numbers multiplied by expected days of activity (60 and 30 for Pier 6 and Pier 4, respectively) to produce take estimate.
\4\ Totals presented for reference only. Negligible impact and small numbers analyses (below) consider the project-specific numbers in columns to left.
\5\ Uncorrected density; presented for reference only.

Analyses and Preliminary Determinations

Negligible Impact Analyses

    NMFS has defined ``negligible impact'' in 50 CFR 216.103 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.'' 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 
Level B harassment 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 behavioral 
harassment, we consider other factors, such as the likely nature of any 
responses (e.g., intensity, duration), the context of any responses

[[Page 44053]]

(e.g., critical reproductive time or location, migration), as well as 
the number and nature of estimated Level A harassment takes, the number 
of estimated mortalities, and effects on habitat.
    To avoid repetition, the discussion below applies to all the 
species listed in Table 8 for which we propose to authorize take, and 
to both separately proposed IHAs (i.e., the Navy's planned activities 
pursuant to the separate Pier 6 and Pier 4 projects), as the 
anticipated effects of both the Pier 6 and Pier 4 maintenance projects 
on marine mammals are expected to be relatively similar in nature. 
There is no information about the nature or severity of the impacts, or 
the size, status, or structure of any species or stock that would lead 
to species- or action-specific analyses for these activities.
    Pile driving activities associated with the pier maintenance 
projects, as outlined previously, have the potential to disturb or 
displace marine mammals. Specifically, the specified activities may 
result in take, in the form of Level B harassment (behavioral 
disturbance) only, from underwater sounds generated from pile driving. 
Potential takes could occur if individuals of these species are present 
in the ensonified zone when pile driving is happening.
    No injury, serious injury, or mortality is anticipated given the 
nature of the activities and measures designed to minimize the 
possibility of injury to marine mammals. The potential for these 
outcomes is minimized through the construction method and the 
implementation of the planned mitigation measures. Specifically, piles 
would be removed via vibratory means--an activity that does not have 
the potential to cause injury to marine mammals due to the relatively 
low source levels produced (less than 180 dB) and the lack of 
potentially injurious source characteristics--and, while impact pile 
driving produces short, sharp pulses with higher peak levels and much 
sharper rise time to reach those peaks, only small diameter concrete 
piles are planned for impact driving (no impact pile driving would 
occur for the Pier 4 project). Predicted source levels for such impact 
driving events are significantly lower than those typical of impact 
driving of steel piles and/or larger diameter piles. In addition, 
implementation of soft start and shutdown zones significantly reduces 
any possibility of injury. Given sufficient ``notice'' through use of 
soft start (for impact driving), marine mammals are expected to move 
away from a sound source that is annoying prior to its becoming 
potentially injurious. Environmental conditions in Sinclair Inlet are 
expected to generally be good, with calm sea states, although Sinclair 
Inlet waters may be more turbid than those further north in Puget Sound 
or in Hood Canal. Nevertheless, we expect conditions in Sinclair Inlet 
would allow a high marine mammal detection capability for the trained 
observers required, enabling a high rate of success in implementation 
of shutdowns to avoid injury, serious injury, or mortality. In 
addition, the topography of Sinclair Inlet should allow for placement 
of observers sufficient to detect cetaceans, should any occur (see 
Figure 1 of Appendix C in the Navy's applications).
    Effects on individuals that are taken by Level B harassment, on the 
basis of reports in the literature as well as monitoring from other 
similar activities, will likely be limited to reactions such as 
increased swimming speeds, increased surfacing time, or decreased 
foraging (if such activity were occurring) (e.g., Thorson and Reyff, 
2006; HDR, Inc., 2012). Most likely, individuals will simply move away 
from the sound source and be temporarily displaced from the areas of 
pile driving, although even this reaction has been observed primarily 
only in association with impact pile driving. The pile driving 
activities analyzed here are similar to, or less impactful than, 
numerous other construction activities conducted in San Francisco Bay 
and in the Puget Sound region, which have taken place with no reported 
injuries or mortality to marine mammals, and no known long-term adverse 
consequences from behavioral harassment. Repeated exposures of 
individuals to levels of sound that may cause Level B harassment are 
unlikely to result in hearing impairment or to significantly disrupt 
foraging behavior. Thus, even repeated Level B harassment of some small 
subset of the overall stock is unlikely to result in any significant 
realized decrease in viability for the affected individuals, and thus 
would not result in any adverse impact to the stock as a whole. Level B 
harassment will be reduced to the level of least practicable impact 
through use of mitigation measures described herein and, if sound 
produced by project activities is sufficiently disturbing, animals are 
likely to simply avoid the area while the activity is occurring.
    In summary, these negligible impact analyses are founded on the 
following factors: (1) The possibility of injury, serious injury, or 
mortality may reasonably be considered discountable; (2) the 
anticipated incidents of Level B harassment consist of, at worst, 
temporary modifications in behavior; (3) the absence of any significant 
habitat within the project area, including rookeries, significant haul-
outs, or known areas or features of special significance for foraging 
or reproduction; (4) the presumed efficacy of the proposed mitigation 
measures in reducing the effects of the specified activity to the level 
of least practicable impact. In addition, these stocks are not listed 
under the ESA or considered depleted under the MMPA. 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 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. Below, we make separate preliminary findings specific to 
each project.
    Pier 6--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, we preliminarily find that the 
total marine mammal take from the Navy's pier maintenance activities 
will have a negligible impact on the affected marine mammal species or 
stocks.
    Pier 4--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, we preliminarily find that the 
total marine mammal take from the Navy's pier maintenance activities 
will have a negligible impact on the affected marine mammal species or 
stocks.

Small Numbers Analyses

    The number of incidents of take proposed for authorization for 
these stocks, specific to each separate project, would be considered 
small relative to the relevant stocks or populations (one percent or 
less for both sea lion stocks and six percent or less for harbor seals; 
Table 8) even if each estimated taking occurred to a new individual. 
This is an extremely unlikely scenario as, for pinnipeds in estuarine/
inland waters, there is likely to be some overlap in individuals 
present day-to-day. Below, we make separate preliminary findings 
specific to each project.
    Pier 6--Based on the analysis contained herein of the likely 
effects of the specified activity on marine mammals and their habitat, 
and taking

[[Page 44054]]

into consideration the implementation of the mitigation and monitoring 
measures, we preliminarily find that small numbers of marine mammals 
will be taken relative to the populations of the affected species or 
stocks.
    Pier 4--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 mitigation and 
monitoring measures, we preliminarily find that small numbers of marine 
mammals will be taken relative to the populations of the affected 
species or stocks.

Impact on Availability of Affected Species for Taking for Subsistence 
Uses

    There are no relevant subsistence uses of marine mammals implicated 
by these actions. Therefore, relevant to both the Pier 6 and Pier 4 
proposed IHAs, we have 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)

    No marine mammal species listed under the ESA are expected to be 
affected by these activities. Therefore, we have determined that 
section 7 consultations under the ESA are not required.

National Environmental Policy Act (NEPA)

    Pier 6--In compliance with the National Environmental Policy Act of 
1969 (42 U.S.C. 4321 et seq.), as implemented by the regulations 
published by the Council on Environmental Quality (40 CFR parts 1500-
1508), the Navy prepared an Environmental Assessment (EA) to consider 
the direct, indirect and cumulative effects to the human environment 
resulting from the pier maintenance project. NMFS made the Navy's EA 
available to the public for review and comment, in relation to its 
suitability for adoption by NMFS in order to assess the impacts to the 
human environment of issuance of an IHA to the Navy. Also in compliance 
with NEPA and the CEQ regulations, as well as NOAA Administrative Order 
216-6, NMFS has reviewed the Navy's EA, determined it to be sufficient, 
and adopted that EA and signed a Finding of No Significant Impact 
(FONSI) on November 8, 2013.
    We have reviewed the Navy's application for a renewed IHA for 
ongoing construction activities for 2015-16 and the 2014-15 monitoring 
report. Based on that review, we have determined that the proposed 
action is very similar to that considered in the previous IHA. In 
addition, no significant new circumstances or information relevant to 
environmental concerns have been identified. Thus, we have determined 
preliminarily that the preparation of a new or supplemental NEPA 
document is not necessary, and will, after review of public comments 
determine whether or not to reaffirm our 2013 FONSI. The 2013 NEPA 
documents are available for review at www.nmfs.noaa.gov/pr/permits/incidental/construction.htm.
    Pier 4--The Navy has prepared a Draft EA in accordance with NEPA 
and the regulations published by the Council on Environmental Quality. 
We have posted it on the NMFS Web site concurrently with the 
publication of this proposed IHA. NMFS will independently evaluate the 
EA and determine whether or not to adopt it. We may prepare a separate 
NEPA analysis and incorporate relevant portions of the Navy's EA by 
reference. Information in the Navy's application, EA, and this notice 
collectively provide the environmental information related to proposed 
issuance of the IHA for public review and comment. We will review all 
comments submitted in response to this notice as we complete the NEPA 
process, including a decision of whether to sign a FONSI, prior to a 
final decision on the IHA request.

Proposed Authorizations

    As a result of these preliminary determinations, we propose to 
issue two separate IHAs to the Navy for conducting the described pier 
maintenance activities in Sinclair Inlet, provided the previously 
mentioned mitigation, monitoring, and reporting requirements are 
incorporated. Specific language from the proposed IHAs is provided 
next.
    This section contains drafts of the IHAs. The wording contained in 
this section is proposed for inclusion in the IHAs (if issued).

Pier 6

    1. This Incidental Harassment Authorization (IHA) is valid from 
September 1, 2015 through March 1, 2016.
    2. This IHA is valid only for pile driving and removal activities 
associated with the Pier 6 Maintenance Project at Naval Base Kitsap 
Bremerton, Washington.
    3. General Conditions.
    (a) A copy of this IHA must be in the possession of the Navy, its 
designees, and work crew personnel operating under the authority of 
this IHA.
    (b) The species authorized for taking are the harbor seal (Phoca 
vitulina), California sea lion (Zalophus californianus), and Steller 
sea lion (Eumetopias jubatus).
    (c) The taking, by Level B harassment only, is limited to the 
species listed in condition 3(b). See Table 1 for numbers of take 
authorized.

              Table 1--Authorized Take Numbers, by Species
------------------------------------------------------------------------
                                                              Authorized
                          Species                                take
------------------------------------------------------------------------
Harbor seal................................................          660
California sea lion........................................        2,880
Steller sea lion...........................................           60
------------------------------------------------------------------------

    (d) The taking by injury (Level A harassment), serious injury, or 
death of any of the species listed in condition 3(b) of the 
Authorization or any taking of any other species of marine mammal is 
prohibited and may result in the modification, suspension, or 
revocation of this IHA.
    (e) The Navy shall conduct briefings between construction 
supervisors and crews, marine mammal monitoring team, acoustic 
monitoring team, and Navy staff prior to the start of all pile driving 
activity, and when new personnel join the work, in order to explain 
responsibilities, communication procedures, marine mammal monitoring 
protocol, and operational procedures.
    4. Mitigation Measures.
    The holder of this Authorization is required to implement the 
following mitigation measures:
    (a) For all pile driving, the Navy shall implement a minimum 
shutdown zone of 10 m radius around the pile. If a marine mammal comes 
within or approaches the shutdown zone, such operations shall cease.
    (b) The Navy shall establish monitoring locations as described 
below. Please also refer to the Marine Mammal Monitoring Plan 
(Monitoring Plan; attached).
    i. For all vibratory pile removal activities, a minimum of two 
observers shall be deployed. One observer shall be located at the pier 
work site, positioned to achieve optimal monitoring of the shutdown 
zone and the surrounding waters of Sinclair Inlet. A minimum of one 
vessel-based observer shall be deployed and shall conduct regular 
transits through the estimated disturbance zone for the duration of the 
activity.
    ii. For all impact pile driving activities, a minimum of one shore-
based observer shall be located at the pier work site.

[[Page 44055]]

    iii. These observers shall record all observations of marine 
mammals, regardless of distance from the pile being driven, as well as 
behavior and potential behavioral reactions of the animals. If any 
killer whales or gray whales are detected, activity must not begin or 
must shut down.
    iv. All observers shall be equipped for communication of marine 
mammal observations amongst themselves and to other relevant personnel 
(e.g., those necessary to effect activity delay or shutdown).
    (c) Prior to the start of pile driving on any day, the Navy shall 
take measures to ensure that no species for which incidental take is 
not authorized are located within the vicinity of the action area, and 
shall contact and/or review the latest sightings data from the Orca 
Network and/or Center for Whale Research, including passive acoustic 
detections, to determine the location of the nearest marine mammal 
sightings.
    (d) Monitoring shall take place from fifteen minutes prior to 
initiation of pile driving activity through thirty minutes post-
completion of pile driving activity. Pre-activity monitoring shall be 
conducted for fifteen minutes to ensure that the shutdown zone is clear 
of marine mammals, and pile driving may commence when observers have 
declared the shutdown zone clear of marine mammals. In the event of a 
delay or shutdown of activity resulting from marine mammals in the 
shutdown zone, animals shall be allowed to remain in the shutdown zone 
(i.e., must leave of their own volition) and their behavior shall be 
monitored and documented. Monitoring shall occur throughout the time 
required to drive a pile. The shutdown zone must be determined to be 
clear during periods of good visibility (i.e., the entire shutdown zone 
and surrounding waters must be visible to the naked eye).
    (e) If a marine mammal approaches or enters the shutdown zone, all 
pile driving activities at that location shall be halted. If pile 
driving is halted or delayed due to the presence of a marine mammal, 
the activity may not commence or resume until either the animal has 
voluntarily left and been visually confirmed beyond the shutdown zone 
or fifteen minutes have passed without re-detection of the animal.
    (f) Monitoring shall be conducted by qualified observers, as 
described in the Monitoring Plan. Trained observers shall be placed 
from the best vantage point(s) practicable to monitor for marine 
mammals and implement shutdown or delay procedures when applicable 
through communication with the equipment operator.
    (g) The Navy shall use soft start techniques recommended by NMFS 
for vibratory and impact pile driving. Soft start for vibratory drivers 
requires contractors to initiate sound for fifteen seconds at reduced 
energy followed by a thirty-second waiting period. This procedure is 
repeated two additional times. Soft start for impact drivers requires 
contractors to provide an initial set of strikes at reduced energy, 
followed by a thirty-second waiting period, then two subsequent reduced 
energy strike sets. Soft start shall be implemented at the start of 
each day's pile driving and at any time following cessation of pile 
driving for a period of thirty minutes or longer. Soft start for impact 
drivers must be implemented at any time following cessation of impact 
driving for a period of thirty minutes or longer.
    (h) Pile driving shall only be conducted during daylight hours.
    5. Monitoring.
    The holder of this Authorization is required to conduct marine 
mammal monitoring during pile driving activity. Marine mammal 
monitoring and reporting shall be conducted in accordance with the 
Monitoring Plan.
    (a) The Navy shall collect sighting data and behavioral responses 
to pile driving for marine mammal species observed in the region of 
activity during the period of activity. All observers shall be trained 
in marine mammal identification and behaviors, and shall have no other 
construction-related tasks while conducting monitoring.
    (b) For all marine mammal monitoring, the information shall be 
recorded as described in the Monitoring Plan.
    (c) The Navy shall conduct acoustic monitoring sufficient to 
measure underwater and airborne source levels for vibratory removal of 
timber piles and impact driving of concrete piles. Minimum requirements 
include:
    i. Measurements shall be taken for a minimum of ten piles of each 
type.
    ii. Each hydrophone (underwater) and microphone (airborne) shall be 
calibrated prior to the beginning of the project and shall be checked 
at the beginning of each day of monitoring activity.
    iii. Environmental data shall be collected including but not 
limited to: wind speed and direction, wave height, water depth, 
precipitation, and type and location of in-water construction 
activities, as well other factors that could contribute to influencing 
the airborne and underwater sound levels measured (e.g. aircraft, 
boats).
    iv. The construction contractor shall supply the Navy and 
monitoring personnel with an estimate of the substrate condition, 
hammer model and size, hammer energy settings and any changes to those 
settings during the piles being monitored.
    v. Post-analysis of data shall include the average, minimum, and 
maximum rms values and frequency spectra for each pile monitored. If 
equipment used is able to accommodate such a requirement, average, 
minimum, and maximum peak values shall also be provided.
    6. Reporting.
    The holder of this Authorization is required to:
    (a) Submit a draft report on all monitoring conducted under the IHA 
within 45 days of the completion of marine mammal and acoustic 
monitoring, or sixty days prior to the issuance of any subsequent IHA 
for this project, whichever comes first. A final report shall be 
prepared and submitted within thirty days following resolution of 
comments on the draft report from NMFS. This report must contain the 
informational elements described in the Monitoring Plan, at minimum 
(see attached), and shall also include:
    i. Detailed information about any implementation of shutdowns, 
including the distance of animals to the pile and description of 
specific actions that ensued and resulting behavior of the animal, if 
any.
    ii. Description of attempts to distinguish between the number of 
individual animals taken and the number of incidences of take, such as 
ability to track groups or individuals.
    iii. A refined take estimate based on the number of marine mammals 
observed during the course of construction activities.
    iv. Results of acoustic monitoring, including the information 
described in condition 5(c) of this authorization.
    (b) Reporting injured or dead marine mammals:
    i. In the unanticipated event that the specified activity clearly 
causes the take of a marine mammal in a manner prohibited by this IHA, 
such as an injury (Level A harassment), serious injury, or mortality, 
Navy shall immediately cease the specified activities and report the 
incident to the Office of Protected Resources, NMFS, and the West Coast 
Regional Stranding Coordinator, NMFS. The report must include the 
following information:
    A. Time and date of the incident;
    B. Description of the incident;
    C. Environmental conditions (e.g., wind speed and direction, 
Beaufort sea state, cloud cover, and visibility);

[[Page 44056]]

    D. Description of all marine mammal observations in the 24 hours 
preceding the incident;
    E. Species identification or description of the animal(s) involved;
    F. Fate of the animal(s); and
    G. Photographs or video footage of the animal(s).
    Activities shall not resume until NMFS is able to review the 
circumstances of the prohibited take. NMFS will work with Navy to 
determine what measures are necessary to minimize the likelihood of 
further prohibited take and ensure MMPA compliance. Navy may not resume 
their activities until notified by NMFS.
    ii. In the event that Navy discovers an injured or dead marine 
mammal, and the lead observer determines that the cause of the injury 
or death is unknown and the death is relatively recent (e.g., in less 
than a moderate state of decomposition), Navy shall immediately report 
the incident to the Office of Protected Resources, NMFS, and the West 
Coast Regional Stranding Coordinator, NMFS.
    The report must include the same information identified in 6(b)(i) 
of this IHA. Activities may continue while NMFS reviews the 
circumstances of the incident. NMFS will work with Navy to determine 
whether additional mitigation measures or modifications to the 
activities are appropriate.
    iii. In the event that Navy discovers an injured or dead marine 
mammal, and the lead observer determines that the injury or death is 
not associated with or related to the activities authorized in the IHA 
(e.g., previously wounded animal, carcass with moderate to advanced 
decomposition, scavenger damage), Navy shall report the incident to the 
Office of Protected Resources, NMFS, and the West Coast Regional 
Stranding Coordinator, NMFS, within 24 hours of the discovery. Navy 
shall provide photographs or video footage or other documentation of 
the stranded animal sighting to NMFS.
    7. This Authorization may be modified, suspended or withdrawn if 
the holder fails to abide by the conditions prescribed herein, or if 
the authorized taking is having more than a negligible impact on the 
species or stock of affected marine mammals.

Pier 4

    1. This Incidental Harassment Authorization (IHA) is valid from 
December 1, 2015, through November 30, 2016.
    2. This IHA is valid only for pile driving and removal activities 
associated with the Pier 4 Maintenance Project at Naval Base Kitsap 
Bremerton, Washington.
    3. General Conditions.
    (a) A copy of this IHA must be in the possession of the Navy, its 
designees, and work crew personnel operating under the authority of 
this IHA.
    (b) The species authorized for taking are the harbor seal (Phoca 
vitulina), California sea lion (Zalophus californianus), and Steller 
sea lion (Eumetopias jubatus).
    (c) The taking, by Level B harassment only, is limited to the 
species listed in condition 3(b). See Table 1 for numbers of take 
authorized.

              Table 1--Authorized Take Numbers, by Species
------------------------------------------------------------------------
                                                              Authorized
                          Species                                take
------------------------------------------------------------------------
Harbor seal................................................          330
California sea lion........................................        1,440
Steller sea lion...........................................           30
------------------------------------------------------------------------

    (d) The taking by injury (Level A harassment), serious injury, or 
death of any of the species listed in condition 3(b) of the 
Authorization or any taking of any other species of marine mammal is 
prohibited and may result in the modification, suspension, or 
revocation of this IHA.
    (e) The Navy shall conduct briefings between construction 
supervisors and crews, marine mammal monitoring team, acoustic 
monitoring team, and Navy staff prior to the start of all pile driving 
activity, and when new personnel join the work, in order to explain 
responsibilities, communication procedures, marine mammal monitoring 
protocol, and operational procedures.
    4. Mitigation Measures.
    The holder of this Authorization is required to implement the 
following mitigation measures:
    (a) For all pile driving, the Navy shall implement a minimum 
shutdown zone of 10 m radius around the pile. If a marine mammal comes 
within or approaches the shutdown zone, such operations shall cease.
    (b) The Navy shall establish monitoring locations as described 
below. Please also refer to the Marine Mammal Monitoring Plan 
(Monitoring Plan; attached).
    i. For all vibratory pile removal activities, a minimum of two 
observers shall be deployed. One observer shall be located at the pier 
work site, positioned to achieve optimal monitoring of the shutdown 
zone and the surrounding waters of Sinclair Inlet. A minimum of one 
vessel-based observer shall be deployed and shall conduct regular 
transits through the estimated disturbance zone for the duration of the 
activity.
    ii. These observers shall record all observations of marine 
mammals, regardless of distance from the pile being driven, as well as 
behavior and potential behavioral reactions of the animals. If any 
killer whales or gray whales are detected, activity must not begin or 
must shut down.
    iii. All observers shall be equipped for communication of marine 
mammal observations amongst themselves and to other relevant personnel 
(e.g., those necessary to effect activity delay or shutdown).
    (c) Prior to the start of pile driving on any day, the Navy shall 
take measures to ensure that no species for which incidental take is 
not authorized are located within the vicinity of the action area, and 
shall contact and/or review the latest sightings data from the Orca 
Network and/or Center for Whale Research, including passive acoustic 
detections, to determine the location of the nearest marine mammal 
sightings.
    (d) Monitoring shall take place from fifteen minutes prior to 
initiation of pile driving activity through thirty minutes post-
completion of pile driving activity. Pre-activity monitoring shall be 
conducted for fifteen minutes to ensure that the shutdown zone is clear 
of marine mammals, and pile driving may commence when observers have 
declared the shutdown zone clear of marine mammals. In the event of a 
delay or shutdown of activity resulting from marine mammals in the 
shutdown zone, animals shall be allowed to remain in the shutdown zone 
(i.e., must leave of their own volition) and their behavior shall be 
monitored and documented. Monitoring shall occur throughout the time 
required to drive a pile. The shutdown zone must be determined to be 
clear during periods of good visibility (i.e., the entire shutdown zone 
and surrounding waters must be visible to the naked eye).
    (e) If a marine mammal approaches or enters the shutdown zone, all 
pile driving activities at that location shall be halted. If pile 
driving is halted or delayed due to the presence of a marine mammal, 
the activity may not commence or resume until either the animal has 
voluntarily left and been visually confirmed beyond the shutdown zone 
or fifteen minutes have passed without re-detection of the animal.
    (f) Monitoring shall be conducted by qualified observers, as 
described in the Monitoring Plan. Trained observers shall be placed 
from the best vantage point(s) practicable to monitor for

[[Page 44057]]

marine mammals and implement shutdown or delay procedures when 
applicable through communication with the equipment operator.
    (g) The Navy shall use soft start techniques recommended by NMFS 
for vibratory pile driving. Soft start for vibratory drivers requires 
contractors to initiate sound for fifteen seconds at reduced energy 
followed by a thirty-second waiting period. This procedure is repeated 
two additional times. Soft start shall be implemented at the start of 
each day's pile driving and at any time following cessation of pile 
driving for a period of thirty minutes or longer.
    (h) Pile driving shall only be conducted during daylight hours.
    5. Monitoring.
    The holder of this Authorization is required to conduct marine 
mammal monitoring during pile driving activity. Marine mammal 
monitoring and reporting shall be conducted in accordance with the 
Monitoring Plan.
    (a) The Navy shall collect sighting data and behavioral responses 
to pile driving for marine mammal species observed in the region of 
activity during the period of activity. All observers shall be trained 
in marine mammal identification and behaviors, and shall have no other 
construction-related tasks while conducting monitoring.
    (b) For all marine mammal monitoring, the information shall be 
recorded as described in the Monitoring Plan.
    6. Reporting.
    The holder of this Authorization is required to:
    (a) Submit a draft report on all monitoring conducted under the IHA 
within 45 days of the completion of marine mammal and acoustic 
monitoring, or sixty days prior to the issuance of any subsequent IHA 
for this project, whichever comes first. A final report shall be 
prepared and submitted within thirty days following resolution of 
comments on the draft report from NMFS. This report must contain the 
informational elements described in the Monitoring Plan, at minimum 
(see attached), and shall also include:
    i. Detailed information about any implementation of shutdowns, 
including the distance of animals to the pile and description of 
specific actions that ensued and resulting behavior of the animal, if 
any.
    ii. Description of attempts to distinguish between the number of 
individual animals taken and the number of incidences of take, such as 
ability to track groups or individuals.
    iii. A refined take estimate based on the number of marine mammals 
observed during the course of construction activities.
    (b) Reporting injured or dead marine mammals:
    i. In the unanticipated event that the specified activity clearly 
causes the take of a marine mammal in a manner prohibited by this IHA, 
such as an injury (Level A harassment), serious injury, or mortality, 
Navy shall immediately cease the specified activities and report the 
incident to the Office of Protected Resources, NMFS, and the West Coast 
Regional Stranding Coordinator, NMFS. The report must include the 
following information:
    A. Time and date of the incident;
    B. Description of the incident;
    C. Environmental conditions (e.g., wind speed and direction, 
Beaufort sea state, cloud cover, and visibility);
    D. Description of all marine mammal observations in the 24 hours 
preceding the incident;
    E. Species identification or description of the animal(s) involved;
    F. Fate of the animal(s); and
    G. Photographs or video footage of the animal(s).
    Activities shall not resume until NMFS is able to review the 
circumstances of the prohibited take. NMFS will work with Navy to 
determine what measures are necessary to minimize the likelihood of 
further prohibited take and ensure MMPA compliance. Navy may not resume 
their activities until notified by NMFS.
    ii. In the event that Navy discovers an injured or dead marine 
mammal, and the lead observer determines that the cause of the injury 
or death is unknown and the death is relatively recent (e.g., in less 
than a moderate state of decomposition), Navy shall immediately report 
the incident to the Office of Protected Resources, NMFS, and the West 
Coast Regional Stranding Coordinator, NMFS.
    The report must include the same information identified in 6(b)(i) 
of this IHA. Activities may continue while NMFS reviews the 
circumstances of the incident. NMFS will work with Navy to determine 
whether additional mitigation measures or modifications to the 
activities are appropriate.
    iii. In the event that Navy discovers an injured or dead marine 
mammal, and the lead observer determines that the injury or death is 
not associated with or related to the activities authorized in the IHA 
(e.g., previously wounded animal, carcass with moderate to advanced 
decomposition, scavenger damage), Navy shall report the incident to the 
Office of Protected Resources, NMFS, and the West Coast Regional 
Stranding Coordinator, NMFS, within 24 hours of the discovery. Navy 
shall provide photographs or video footage or other documentation of 
the stranded animal sighting to NMFS.
    7. This Authorization may be modified, suspended or withdrawn if 
the holder fails to abide by the conditions prescribed herein, or if 
the authorized taking is having more than a negligible impact on the 
species or stock of affected marine mammals.

Request for Public Comments

    We request comment on our analyses, the draft authorizations, and 
any other aspect of this Notice of Proposed IHAs for Navy's pier 
maintenance activities. Please include with your comments any 
supporting data or literature citations to help inform our final 
decision on Navy's request for an MMPA authorization.

    Dated: July 20, 2015.
Perry F. Gayaldo,
Deputy Director, Office of Protected Resources, National Marine 
Fisheries Service.
[FR Doc. 2015-18145 Filed 7-23-15; 8:45 am]
 BILLING CODE 3510-22-P