[Federal Register Volume 81, Number 153 (Tuesday, August 9, 2016)]
[Notices]
[Pages 52645-52665]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2016-18847]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

RIN 0648-XE744


Takes of Marine Mammals Incidental to Specified Activities; 
Taking Marine Mammals Incidental to a Pier Replacement Project

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

ACTION: Notice; proposed incidental harassment authorization; request 
for comments.

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SUMMARY: NMFS has received a request from the U.S. Navy (Navy) for 
authorization to take marine mammals incidental to construction 
activities as part of a pier replacement project. Pursuant to the 
Marine Mammal Protection Act (MMPA), NMFS is requesting comments on its 
proposal to issue an incidental harassment authorization (IHA) to the 
Navy to incidentally take marine mammals, by

[[Page 52646]]

Level B Harassment only, during the specified activity.

DATES: Comments and information must be received no later than 
September 8, 2016.

ADDRESSES: Comments on the application 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)

    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 the existing EA and FONSI provide adequate analysis 
related to the potential environmental effects of issuing an IHA to the 
Navy, prior to a final decision on the incidental take authorization 
request.

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, the 
incidental, but not intentional, taking of small numbers of marine 
mammals by U.S. citizens who engage in a specified activity (other than 
commercial fishing) within a specified geographical region if certain 
findings are made and either regulations are issued or, if the taking 
is limited to harassment, a notice of a proposed authorization is 
provided to the public for review.
    Authorization for incidental takings shall be granted if NMFS finds 
that the taking will have a negligible impact on the species or 
stock(s), will not have an unmitigable adverse impact on the 
availability of the species or stock(s) for subsistence uses (where 
relevant), and if the permissible methods of taking and requirements 
pertaining to the mitigation, monitoring and reporting of such takings 
are set forth. 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.''
    Section 101(a)(5)(D) of the MMPA established an expedited process 
by which citizens of the U.S. can apply for an authorization to 
incidentally take small numbers of marine mammals by harassment. 
Section 101(a)(5)(D) establishes a 45-day time limit for NMFS review of 
an application followed by a 30-day public notice and comment period on 
any proposed authorizations for the incidental harassment of marine 
mammals. Within 45 days of the close of the comment period, NMFS must 
either issue or deny the authorization. Except with respect to certain 
activities not pertinent here, 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 Request

    On June 16, 2016, we received a request from the Navy for 
authorization to take marine mammals incidental to pile installation 
and demolition associated with a pier replacement project in San Diego 
Bay at Naval Base Point Loma in San Diego, CA (NBPL), including a 
separate monitoring plan. The Navy also submitted a draft monitoring 
report on June 2, 2016, pursuant to requirements of the previous IHA. 
The Navy submitted revised versions of the request and monitoring plan 
on August 3, 2016, and a revised monitoring report on July 12, 2016. 
These documents were deemed adequate and complete. The pier replacement 
project is planned to occur over multiple years; this proposed IHA 
would cover only the fourth year of work and would be valid for a 
period of one year from the date of issuance. Hereafter, use of the 
generic term ``pile driving'' may refer to both pile installation and 
removal unless otherwise noted.
    The use of both vibratory and impact pile driving, as well as 
various demolition techniques, 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 window include the 
California sea lion (Zalophus californianus), harbor seal (Phoca 
vitulina richardii), northern elephant seal (Mirounga angustirostris), 
gray whale (Eschrichtius robustus), bottlenose dolphin (Tursiops 
truncatus truncatus), Pacific white-sided dolphin (Lagenorhynchus 
obliquidens), Risso's dolphin (Grampus griseus), and either short-
beaked or long-beaked common dolphins (Delphinus spp.). California sea 
lions are present year-round and are very common in the project area, 
while bottlenose dolphins and harbor seals are common and likely to be 
present year-round but with more variable occurrence in San Diego Bay. 
Gray whales may be observed in San Diego Bay sporadically during 
migration periods. The remaining species are known to occur in 
nearshore waters outside San Diego Bay, but are generally only rarely 
observed near or in the bay. However, recent observations indicate that 
these species may occur in the project area and therefore could 
potentially be subject to incidental

[[Page 52647]]

harassment from the aforementioned activities.
    This would be the fourth such IHA, if issued, following the IHAs 
issued effective from September 1, 2013, through August 31, 2014 (78 FR 
44539), from October 8, 2014, through October 7, 2015 (79 FR 65378), 
and from October 8, 2015, through October 7, 2016 (80 FR 62032). 
Monitoring reports are available on the Internet at www.nmfs.noaa.gov/pr/permits/incidental/construction.htm and provide environmental 
information related to proposed issuance of this IHA for public review 
and comment.

Description of the Specified Activity

Overview

    NBPL provides berthing and support services for Navy submarines and 
other fleet assets. The existing fuel pier serves as a fuel depot for 
loading and unloading tankers and Navy underway replenishment vessels 
that refuel ships at sea (``oilers''), as well as transferring fuel to 
local replenishment vessels and other small craft operating in San 
Diego Bay, and is the only active Navy fueling facility in southern 
California. Portions of the pier are over one hundred years old, while 
the newer segment was constructed in 1942. The pier as a whole is 
significantly past its design service life and does not meet current 
construction standards.
    The Navy plans to demolish and remove the existing pier and 
associated pipelines and appurtenances while simultaneously replacing 
it with a generally similar structure that meets relevant standards for 
seismic strength and is designed to better accommodate modern Navy 
ships. Demolition and construction are planned to occur in two phases 
to maintain the fueling capabilities of the existing pier while the new 
pier is being constructed. During the fourth year of construction (the 
specified activity considered under this proposed IHA), the Navy 
anticipates construction at two locations: the fuel pier area and at 
the Naval Mine and Anti-Submarine Warfare Command (NMAWC), where the 
Navy's Marine Mammal Program (MMP) was temporarily moved during fuel 
pier construction (see Figure 1-1 in the Navy's application). At the 
fuel pier, the Navy anticipates driving remaining concrete fender piles 
and driving remaining steel piles for mooring dolphins. At NMAWC, Navy 
anticipates extracting and driving concrete piles as needed to return 
the existing facility to its configuration prior to temporary placement 
of the MMP, which will be returned to its previous location near the 
fuel pier. For construction work at the fuel pier, Navy anticipates 
driving approximately 24 30-in steel pipe piles, 81 30 x 24-in concrete 
piles, and one 16-in concrete-filled fiberglass pile. Steel pipe piles 
would be installed to refusal using a vibratory driver and then 
finished using an impact hammer; concrete piles would be installed to 
within five feet of tip elevation via jetting before being finished 
with an impact hammer, and the fiberglass pile would be installed 
entirely using an impact hammer. At NMAWC, Navy anticipates driving 21 
16-in concrete piles using an impact hammer and removing forty existing 
16-in concrete piles used for the temporary MMP relocation. See Table 
1-4 in the Navy's application for more detail on piles to be installed.
    The majority of demolition activity of the existing pier would 
occur concurrently during this fourth IHA period, including the removal 
of approximately 458 steel, concrete, and plastic piles and 51 
concrete-filled steel caissons. Removals may occur by multiple means, 
including vibratory removal, hydraulic pile cutter, torch cutter, dead 
pull, and diamond saw, as determined to be most effective. See Table 1-
3 in the Navy's application for more detail on piles to be removed.
    The proposed actions with the potential to incidentally harass 
marine mammals within the waters adjacent to NBPL are vibratory and 
impact pile installation and certain demolition (i.e., pile removal) 
techniques when not occurring concurrently with pile installation. 
Concurrent use of multiple pile driving rigs is not planned.

Dates and Duration

    The proposed activities that would be authorized by this IHA, 
during the fourth year of work associated with the fuel pier project, 
would occur for one year from the date of issuance of this proposed 
IHA. Under the terms of a memorandum of understanding (MOU) between the 
Navy and the U.S. Fish and Wildlife Service (FWS), all noise- and 
turbidity-producing in-water activities in designated least tern 
foraging habitat are to be avoided during the period when least terns 
are present and engaged in nesting and foraging (a window from 
approximately May 1 through September 15). However, it is possible that 
in-water work not expected to result in production of significant noise 
or turbidity (e.g., demolition activities) could occur at any time 
during the period of validity of this proposed IHA. The conduct of any 
such work would be subject to approval from FWS under the terms of the 
MOU. We expect that in-water construction work would primarily occur 
from October through April. Pile driving would occur during normal 
working hours (approximately 7 a.m. to 6 p.m.), and would not occur 
earlier than 45 minutes after sunrise or later than 45 minutes before 
sunset.

Specific Geographic Region

    NBPL is located on the peninsula of Point Loma near the mouth and 
along the northern edge of San Diego Bay (see Figures 1-1 and 1-2 in 
the Navy's application). San Diego Bay is a narrow, crescent-shaped 
natural embayment oriented northwest-southeast with an approximate 
length of 24 km and a total area of roughly 4,500 ha. The width of the 
bay ranges from 0.3 to 5.8 km, and depths range from 23 m mean lower 
low water (MLLW) near the tip of Ballast Point to less than 2 m at the 
southern end (see Figure 2-1 of the Navy's application). San Diego Bay 
is a heavily urbanized area with a mix of industrial, military, and 
recreational uses. The northern and central portions of the bay have 
been shaped by historic dredging to support large ship navigation. 
Dredging occurs as necessary to maintain constant depth within the 
navigation channel. Outside the navigation channel, the bay floor 
consists of platforms at depths that vary slightly. Sediments in 
northern San Diego Bay are relatively sandy as tidal currents tend to 
keep the finer silt and clay fractions in suspension, except in harbors 
and elsewhere in the lee of structures where water movement is 
diminished. Much of the shoreline consists of riprap and manmade 
structures. San Diego Bay is heavily used by commercial, recreational, 
and military vessels, with an average of over 80,000 vessel movements 
(in or out of the bay) per year (not including recreational boating 
within the Bay) (see Table 2-2 of the Navy's application). For more 
information about the specific geographic region, please see section 
2.3 of the Navy's application.

Detailed Description of Activities

    In order to provide context, we described the entire project in our 
Federal Register notice of proposed authorization associated with the 
first-year IHA (78 FR 30873; May 23, 2013). Please see that document 
for an overview of the entire fuel pier replacement project, or see the 
Navy's Environmental Assessment (2013) for more detail. Here, we 
provide an overview of relevant construction methods before describing 
only the specific project portions scheduled for completion during the 
third work window. Please see section 1 of the

[[Page 52648]]

Navy's application for full detail of construction scheduling for this 
period. For the fourth year of work, approximately 106 steel and 
concrete piles would be installed, completing in-water construction 
work for the new pier (with a total of approximately 518 steel and 
concrete piles installed). The Navy anticipates the need to request a 
fifth IHA related to completion of demolition work.
    Methods, Pile Installation--Vibratory hammers, which can be used to 
either install or extract a pile, contain a system of counter-rotating 
eccentric weights powered by hydraulic motors and are designed in such 
a way that horizontal vibrations cancel out, while vertical vibrations 
are transmitted into the pile. The pile driving machine is lifted and 
positioned over the pile by means of an excavator or crane, and is 
fastened to the pile by a clamp and/or bolts. The vibrations produced 
cause liquefaction of the substrate surrounding the pile, enabling the 
pile to be extracted or driven into the ground using the weight of the 
pile plus the hammer. Impact hammers use a rising and falling piston to 
repeatedly strike a pile and drive it into the ground.
    Steel piles are typically vibratory-driven for their initial 
embedment depths or to refusal and finished with an impact hammer for 
proofing or until the pile meets structural requirements, as necessary. 
Proofing involves striking a driven pile with an impact hammer to 
verify that it provides the required load-bearing capacity, as 
indicated by the number of hammer blows per foot of pile advancement. 
Non-steel piles are typically impact-driven for their entire embedment 
depth, in part because non-steel piles are often displacement piles (as 
opposed to pipe piles) and require some impact to allow substrate 
penetration. However, jetting may be used to advance displacement piles 
to a certain embedment depth. Pile jetting utilizes a directed and flow 
of pressurized water to assist in pile placement. The jetting technique 
liquefies the soils at the pile tip during pile placement, reducing the 
friction between adjacent sub-grade soil particles around the water 
jet. This greatly decreases the bearing capacity of the soils below the 
pile tip, causing the pile to descend toward its final tip elevation 
with much less soil resistance, largely under its own weight.
    Methods, Pile Removal--There are multiple methods for pile removal. 
During previous demolition, piles were generally removed by cutting at 
the mudline, which can be accomplished in various ways. Piles are 
expected to be removed during this fourth-year IHA primarily using a 
pile cutter, which is a bladed hydraulic device that shears the pile 
off. The preferred method of removing the caisson elements is to cut 
them at the mudline and then into two sections using a diamond wire 
cutting saw. Existing caisson elements would be removed with a 
clamshell, which is a dredging bucket consisting of two similar halves 
that open/close at the bottom and are hinged at the top. The clamshell 
would be used to grasp and lift large components.
    Piles may also be removed by simply dry pulling, or pulling after 
the pile has been loosened using a vibratory hammer or a pneumatic 
chipper. Jetting may be another option to loosen piles that could not 
be removed through the previous procedures. Pile removal is not 
generally expected to require the use of vibratory extraction or 
pneumatic chipping, and these methods are considered as contingency in 
the event other methods of extraction are not successful.
    Construction--Construction work during the proposed fourth year of 
activity would include driving of steel pipe piles to complete 
construction of mooring dolphins and driving of concrete fender piles 
for the new pier and mooring dolphins. This work is expected to require 
a total of 53 days.
    Demolition--Demolition of the old pier will continue during 
construction activity. Much of the demolition work will be above-water, 
involving removal of decking, utilities, and appurtenances, but in-
water structure removal will also occur, as described above under 
``Methods, Pile Removal.'' The in-water portion of demolition work 
planned during the period of this proposed IHA is expected to require 
156 days in total.
    NMAWC--As described above, the Navy also plans to return the MMP to 
its permanent location near the fuel pier, requiring extraction and 
installation of concrete piles to return the NMAWC site to its original 
condition. This work is expected to require eighteen days.

Description of Work Accomplished

    During the first in-water work season (2013-14), two primary 
activities were conducted: Relocation of the MMP and the Indicator Pile 
Program (IPP). During the second in-water work season (2014-15), the 
IPP was concluded and simultaneous construction of the new pier and 
demolition of the old pier begun. Production pile driving continued 
during the third in-water work season (2015-16).
    The Navy MMP, administered by Space and Naval Warfare Systems 
Command Systems Center, was moved approximately three kilometers to the 
NMAWC (see Figures 1-1 and 1-2 of the Navy's Year 1 monitoring report). 
Although not subject to the MMPA, SSC's working animals were 
temporarily relocated so that they will not be affected by the project. 
Over the course of 25 in-water construction days from January 28 to 
March 13, 2014, the Navy removed thirty and installed 81 concrete piles 
(12- and 16-in). See Table 3-2 of the Navy's Year 1 monitoring report 
for details. Installation was accomplished via a D19-42 American Pile 
Driving Equipment, Inc. (APE) diesel hammer with energy capacity of 
23,566-42,800 ft-lbs and fitted with a hydraulic tripping cylinder with 
four adjustable power settings that could be reset while driving. Pile 
removal was accomplished by jetting and dead pull.
    The IPP was designed to validate the length of pile required and 
the method of installation (vibratory and impact) as well as to 
validate acoustic sound pressure levels of the various sizes and 
locations (i.e., shallow versus deeper water) of installed piles. Nine 
steel pipe test piles were vibratory- and impact-driven over ten work 
days from April 28 to May 15, 2014, including two 30-in and seven 36-in 
piles. All piles were initially installed using an APE Variable Moment 
250 VM Vibratory Hammer Extractor powered by a model 765 hydraulic 
power source creating a maximum driving force of 2,389 kilonewtons (269 
tons). Impact pile driving equipment consisted of a single acting 
diesel impact hammer model D62-22 DELMAG with energy capacity of 
76,899-153,799 ft-lbs and fitted with a hydraulic tripping cylinder 
with four adjustable power settings that could be reset while driving. 
One additional 36-in pile was installed in Spring 2015, under the Year 
2 IHA, to conclude the IPP.
    Production pile driving associated with construction of the new 
pier was begun in Fall 2014 and continued into Spring 2015. Both 
vibratory and impact driving was used, as described above, to install 
238 steel pipe piles (four 18-in, 31 30-in, and 203 36-in diameter). 
Hammers used were the same as those described above. Demolition 
activity was begun in Spring 2015, and included the removal of four 
caissons, eighteen concrete fender piles, and a portion of concrete 
decking from the existing fuel pier. In total, this work consisted of 
one hundred days of activity from October 16, 2014, through April 29, 
2015. Of these one hundred days of in-water work, eighteen days 
involved only impact driving, fifteen days included only vibratory 
driving, and 65 days where both types of driving occurred.

[[Page 52649]]

The remaining two days involved only demolition activities. Please see 
the Year 2 monitoring report for more information.
    Production pile driving continued in early 2016 during three 
distinct construction periods from January 11 through April 30, 2016, 
with 161 piles installed over the course of fifty days. Because most 
structural steel pipe piles were installed under the Year 2 IHA, this 
work primarily involved placement of non-structural concrete fender 
piles. Both vibratory and impact driving was used, as described above, 
to install 132 16-in polycarbonate coated concrete fender piles and 23 
24 x 30-in concrete fender piles. In addition, six 30-in steel pipe 
piles were installed as structural elements to support a mooring 
dolphin. Hammers used for the steel piles were the same as those 
described above. The 16-in concrete piles were driven using an APE 
single action diesel impact hammer model D25-32, with energy capacity 
of 29,484-58,245 ft-lbs and fitted with a manual power level modulator 
and shut off trip. The 24 x 30-in concrete piles were driven using an 
APE single action diesel impact hammer model D80-42, with energy 
capacity of 127,008-198,450 ft-lbs and fitted with a manual power level 
modulator and shut off trip. No demolition occurred during this period. 
Of the 50 days of in-water work, 45 days involved only impact driving, 
two days included only vibratory driving, and three days where both 
types of driving occurred. Please see the Year 3 monitoring report for 
more information. Additional work may be conducted under the existing 
IHA between September 15 and October 7, 2016, in which case the 
submitted monitoring report would be amended as necessary.

Description of Marine Mammals in the Area of the Specified Activity

    There are four marine mammal species which are either resident or 
have known seasonal occurrence in the vicinity of San Diego Bay, 
including the California sea lion, harbor seal, bottlenose dolphin, and 
gray whale (see Figures 3-1 through 3-4 and 4-1 in the Navy's 
application). In addition, common dolphins (see Figure 3-4 in the 
Navy's application), the Pacific white-sided dolphin, Risso's dolphin, 
and northern elephant seals are known to occur in deeper waters in the 
vicinity of San Diego Bay and/or have been observed within the bay 
during the course of this project's monitoring. Although the latter 
three species of cetacean would not generally be expected to occur 
within the project area, the potential for changes in occurrence 
patterns in conjunction with recent observations leads us to believe 
that authorization of incidental take is warranted. Common dolphins 
have been documented regularly at the Navy's nearby Silver Strand 
Training Complex, and were observed in the project area during previous 
years of project activity. The Pacific white-sided dolphin has been 
sighted along a previously used transect on the opposite side of the 
Point Loma peninsula (Merkel and Associates, 2008) and there were 
several observations of Pacific white-sided dolphins during Year 2 
monitoring. Risso's dolphin is fairly common in southern California 
coastal waters (e.g., Campbell et al., 2010), and could occur in the 
bay. Northern elephant seals are included based on their continuing 
increase in numbers along the Pacific coast (Carretta et al., 2016) and 
the likelihood that animals that reproduce on the islands offshore of 
Baja California and mainland Mexico--where the population is also 
increasing--could move through the project area during migration, as 
well as the observation of a juvenile seal near the fuel pier in April 
2015.
    Note that common dolphins could be either short-beaked (Delphinus 
delphis delphis) or long-beaked (D. delphis bairdii). While it is 
likely that common dolphins observed in the project area would be long-
beaked, as it is the most frequently stranded species in the area from 
San Diego Bay to the U.S.-Mexico border (Danil and St. Leger, 2011), 
the species distributions overlap and it is unlikely that observers 
would be able to differentiate them in the field. Therefore, we 
consider that any common dolphins observed--and any incidental take of 
common dolphins--could be either stock.
    In addition, other species that occur in the Southern California 
Bight may have the potential for isolated occurrence within San Diego 
Bay or just offshore. In particular, a short-finned pilot whale 
(Globicephala macrorhynchus) was observed off Ballast Point, and a 
Steller sea lion (Eumetopias jubatus monteriensis) was seen in the 
project area during Year 2. These species are not typically observed 
near the project area and, unlike the previously mentioned species, we 
do not believe it likely that they will occur in the future. Given the 
unlikelihood of their exposure to sound generated from the project, 
these species are not considered further.
    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 Southern 
California and Point Mugu Operating Areas, which provides information 
regarding the biology and behavior of the marine resources that may 
occur in those operating areas (DoN, 2008). 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 26, 2016). In addition, we provided information for the 
potentially affected stocks, including details of stock-wide status, 
trends, and threats, in our Federal Register notices of proposed 
authorization associated with the first- and second-year IHAs (78 FR 
30873; May 23, 2013 and 79 FR 53026; September 5, 2014) and refer the 
reader to those documents rather than reprinting the information here.
    Table 1 lists the marine mammal species with expected potential for 
occurrence in the vicinity of NBPL during the project timeframe and 
summarizes key information regarding stock status and abundance. See 
also Figures 3-1 through 3-5 of the Navy's application for observed 
occurrence of marine mammals in the project area. Taxonomically, we 
follow Committee on Taxonomy (2016). 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. All 
potentially affected species are addressed in the Pacific SARs 
(Carretta et al., 2016).

[[Page 52650]]



                                           Table 1--Marine Mammals Potentially Present in the Vicinity of NBPL
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                  Stock abundance                                    Relative occurrence
                                                           ESA/MMPA status;       (CV, Nmin, most                      Annual M/SI    in San Diego Bay;
             Species                       Stock          Strategic (Y/N) \1\    recent abundance        PBR \3\           \4\            season of
                                                                                    survey) \2\                                           occurrence
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                          Order Cetartiodactyla--Cetacea--Superfamily Mysticeti (baleen whales)
                                                                  Family Eschrichtiidae
--------------------------------------------------------------------------------------------------------------------------------------------------------
Gray whale.......................  Eastern North         -; N                  20,990 (0.05;                    624             132  Occasional
                                    Pacific.                                    20,125; 2011).                                        migratory visitor;
                                                                                                                                      winter.
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                            Superfamily Odontoceti (toothed whales, dolphins, and porpoises)
                                                                   Family Delphinidae
--------------------------------------------------------------------------------------------------------------------------------------------------------
Bottlenose dolphin...............  California coastal..  -; N                  323 \5\ (0.13; 290;              2.4             0.2  Common; year-round.
                                                                                2005).
Short-beaked common dolphin......  California/Oregon/    -; N                  411,211 (0.21;                 3,440              64  Occasional; year-
                                    Washington.                                 343,990; 2008).                                       round (but more
                                                                                                                                      common in warm
                                                                                                                                      season).
Long-beaked common dolphin.......  California..........  -; N                  107,016 (0.42;                   610            13.8  Occasional; year-
                                                                                76,224; 2009).                                        round (but more
                                                                                                                                      common in warm
                                                                                                                                      season).
Pacific white-sided dolphin......  California/Oregon/    -; N                  26,930 (0.28;                    171            17.8  Uncommon; year-
                                    Washington.                                 21,406; 2008).                                        round.
Risso's dolphin..................  California/Oregon/    -; N                  6,272 (0.3; 4,913;                39             1.6  Rare; year-round
                                    Washington.                                 2008).                                                (but more common
                                                                                                                                      in cool season).
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                         Order Carnivora--Superfamily Pinnipedia
                                                      Family Otariidae (eared seals and sea lions)
--------------------------------------------------------------------------------------------------------------------------------------------------------
California sea lion..............  U.S.................  -; N                  296,750 (n/a;                  9,200             389  Abundant; year-
                                                                                153,337; 2011).                                       round.
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                             Family Phocidae (earless seals)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Harbor seal......................  California..........  -; N                  30,968 (n/a; 27,348;           1,641              43  Common; year-round.
                                                                                2012).
Northern elephant seal...........  California breeding.  -; N                  179,000 (n/a;                  4,882             8.8  Rare; year-round.
                                                                                81,368; 2010).
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Endangered Species Act (ESA) status: Endangered (E), Threatened (T)/MMPA status: Depleted (D). A dash (-) indicates that the species is not listed
  under the ESA or designated as depleted under the MMPA. Under the MMPA, a strategic stock is one for which the level of direct human-caused mortality
  exceeds PBR (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 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.
\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.
\5\ This value is based on photographic mark-recapture surveys conducted along the San Diego coast in 2004-05, but is considered a likely underestimate,
  as it does not reflect that approximately 35 percent of dolphins encountered lack identifiable dorsal fin marks (Defran and Weller, 1999). If 35
  percent of all animals lack distinguishing marks, then the true population size would be closer to 450-500 animals (Carretta et al., 2016).

Gray Whale

    Two populations of gray whales are recognized, Eastern and Western 
North Pacific (ENP and WNP). 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., 2011). 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.

[[Page 52651]]

    However, only ENP whales are expected to occur in the project area. 
The likelihood of any gray whale being exposed to project sound to the 
degree considered in this document is already low, as it would require 
a migrating whale to linger for an extended period of time, or for 
multiple migrating whales to linger for shorter periods of time. While 
such an occurrence is not unknown, it is uncommon. Further, of the 
approximately 20,000 gray whales migrating through the Southern 
California Bight, it is extremely unlikely that one found in San Diego 
Bay would be one of the approximately twenty WNP whales that have been 
documented in the eastern Pacific (less than one percent probability). 
The likelihood that a WNP whale would be exposed to elevated levels of 
sound from the specified activities is insignificant and discountable 
and WNP whales are not considered further in this document.

Potential Effects of the Specified Activity on Marine Mammals and Their 
Habitat

    We provided discussion of the potential effects of the specified 
activity on marine mammals and their habitat in our Federal Register 
notices of proposed authorization associated with the first- and 
second-year IHAs (78 FR 30873; May 23, 2013 and 79 FR 53026; September 
5, 2014). The specified activity associated with this proposed IHA is 
substantially similar to those considered for the first- and second-
year IHAs and the potential effects of the specified activity are the 
same as those identified in those documents. Therefore, we do not 
reprint the information here but refer the reader to those documents.
    In the aforementioned Federal Register notices, we also provided 
general background information on sound and marine mammal hearing and a 
description of sound sources and ambient sound and refer the reader to 
those documents. However, because certain terms are used frequently in 
this document, we provide brief definitions of relevant acoustic 
terminology below:
     Sound pressure level (SPL): Sound pressure is the force 
per unit area, usually expressed in microPascals ([mu]Pa), where one 
Pascal equals one Newton exerted over an area of one square meter. The 
SPL is expressed in decibels (dB) as twenty times the logarithm to the 
base ten of the ratio between the pressure exerted by the sound to a 
referenced sound pressure. SPL is the quantity that is directly 
measured by a sound level meter. For underwater sound, SPL in dB is 
referenced to one microPascal (re 1 [mu]Pa), unless otherwise stated. 
For airborne sound, SPL in dB is referenced to 20 microPascals (re 20 
[mu]Pa), unless otherwise stated.
     Frequency: Frequency is expressed in terms of 
oscillations, or cycles, per second. Cycles per second are commonly 
referred to as hertz (Hz). Typical human hearing ranges from 20 Hz to 
20 kilohertz (kHz).
     Peak sound pressure: The instantaneous maximum of the 
absolute positive or negative pressure over the frequency range from 20 
Hz to 20 kHz and presented in dB.
     Root mean square (rms) SPL: For impact pile driving, 
overall dB rms levels are characterized by integrating sound for each 
waveform across ninety percent of the acoustic energy in each wave and 
averaging all waves in the pile driving event. This value is referred 
to as the rms 90%. With this method, the time averaging per pulse 
varies.
     Sound Exposure Level (SEL): A measure of energy, 
specifically the dB level of the time integral of the squared-
instantaneous sound pressure, normalized to a one second period. It is 
an useful metric for assessing cumulative exposure because it enables 
sounds of differing duration, to be compared in terms of total energy. 
The accumulated SEL (SELcum) is used to describe the SEL 
from multiple events (e.g., many pile strikes). This can be calculated 
directly as a logarithmic sum of the individual single-strike SELs for 
the pile strikes that were used to install the pile.
     Level Z weighted (unweighted), equivalent 
(LZeq): LZeq is a value recorded by the SLM that 
represents SEL SPL over a specified time period or interval. The LZeq 
is most typically referred to in one-second intervals or over an entire 
event.
     Level Z weighted (unweighted), fast (LZFmax): 
LZFmax is a value recorded by the SLM that represents the 
maximum rms value recorded for any 125 millisecond time frame during 
each individual recording.

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.
    The mitigation strategies described below largely follow those 
required and successfully implemented under the first three IHAs 
associated with this project. For this proposed IHA, data from acoustic 
monitoring conducted during the first three years of work was used to 
estimate zones of influence (ZOIs; see ``Estimated Take by Incidental 
Harassment''); these values were used to develop mitigation measures 
for pile driving activities at NBPL. The ZOIs effectively represent the 
mitigation zone that would be established around each pile to minimize 
Level A harassment to marine mammals, while providing estimates of the 
areas within which Level B harassment might occur. In addition, the 
Navy has defined buffers to the estimated Level A harassment zones to 
further reduce the potential for Level A harassment. In addition to the 
measures described later in this section, the Navy would 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.

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 and removal activities, the 
Navy will establish a shutdown zone intended to contain the area in 
which SPLs equal or exceed NMFS' historical 180/190 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 (serious injury or death are 
unlikely outcomes even in the absence of mitigation measures). 
Estimated radial distances to the relevant thresholds are shown in 
Table 5. For certain activities, the shutdown zone would not exist 
because source levels are lower than the threshold, or the source 
levels indicate that the radial distance to the threshold would be less 
than 10 m. However, a minimum shutdown zone of 10 m will be established 
during all pile driving and removal activities, regardless of the 
estimated zone. In addition the Navy proposes to effect a buffered 
shutdown zone that is intended to significantly reduce the potential 
for Level A harassment given that, in particular, California sea lions 
are quite abundant in the project area and bottlenose

[[Page 52652]]

dolphins may surface unpredictably and move erratically in an area with 
a large amount of construction equipment. The Navy considered typical 
swim speeds (Godfrey, 1985; Lockyer and Morris, 1987; Fish, 1997; Fish 
et al., 2003; Rohr et al., 2002; Noren et al., 2006) and past field 
experience (e.g., typical elapsed time from observation of an animal to 
shutdown of equipment) in initially defining these buffered zones, and 
then evaluated the practicality and effectiveness of the zones during 
the Years 2-3 construction periods. The Navy will add a buffer of 75 m 
and 150 m to the estimated Level A harassment zones for impact driving 
of steel piles for pinnipeds and cetaceans, respectively, (incerasing 
the effective zones to 150 m and 450 m radius. These zones are also 
shown in Table 5. These precautionary measures are intended to prevent 
the already unlikely possibility of physical interaction with 
construction equipment and to establish a precautionary minimum zone 
with regard to acoustic effects.
    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. If acoustic monitoring is being conducted for that pile, a 
received SPL may be estimated, or the received level may be estimated 
on the basis of past or subsequent acoustic monitoring. It may then be 
determined whether the animal was exposed to sound levels constituting 
incidental harassment in post-processing of observational and acoustic 
data, and a precise accounting of observed incidences of harassment 
created. Therefore, although the predicted distances to behavioral 
harassment thresholds are useful for estimating incidental harassment 
for purposes of authorizing levels of incidental take, actual take may 
be determined in part through the use of empirical data.
    Acoustic measurements will continue during the fourth year of 
project activity and zones would be adjusted as indicated by empirical 
data. Please see the Navy's Acoustic and Marine Species Monitoring Plan 
(Monitoring Plan; available at www.nmfs.noaa.gov/pr/permits/incidental/construction.htm) for full details.
    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 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 Monitoring Plan 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 (as defined in the 
Monitoring Plan) 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 is 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 and for thirty minutes 
following the conclusion of pile driving.

Sound Attenuation Devices

    The use of bubble curtains to reduce underwater sound from impact 
pile driving was considered prior to the start of the project but was 
determined to not be practicable. Use of a bubble curtain in a channel 
with substantial current

[[Page 52653]]

may not be effective, as unconfined bubbles are likely to be swept away 
and confined curtain systems may be difficult to deploy effectively in 
high currents. Data gathered during monitoring of construction on the 
San Francisco-Oakland Bay Bridge indicated that no reduction in the 
overall linear sound level resulted from use of a bubble curtain in 
deep water with relatively strong current, and the distance to the 190 
dB zone was considered to be the same with and without the bubble 
curtain (Illingworth & Rodkin, 2001). During project monitoring for 
pile driving associated with the Richmond-San Rafael Bridge, also in 
San Francisco Bay, it was observed that performance in moderate current 
was significantly reduced (Oestman et al., 2009). Lucke et al. (2011) 
also note that the effectiveness of most currently used curtain designs 
may be compromised in stronger currents and greater water depths. We 
believe that conditions (relatively deep water and strong tidal 
currents of up to 3 kn) at the project site would disperse the bubbles 
and compromise the effectiveness of sound attenuation.

Timing Restrictions

    In-order to avoid impacts to least tern populations when they are 
most likely to be foraging and nesting, in-water work will be 
concentrated from October 1-April 1 or, depending on circumstances, to 
April 30. However, this limitation is in accordance with agreements 
between the Navy and FWS, and is not a requirement of this proposed 
IHA. All in-water construction activities would occur only from 45 
minutes after sunrise to 45 minutes before 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 project will utilize soft start techniques 
for impact pile 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 impact pile driving work and 
at any time following a cessation of impact pile driving of thirty 
minutes or longer; the requirement to implement soft start for impact 
driving is independent of whether vibratory driving has occurred within 
the prior thirty minutes.
    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.

[[Page 52654]]

     Mitigation and monitoring effectiveness.
    Please see the Monitoring Plan (available at www.nmfs.noaa.gov/pr/permits/incidental/construction.htm) for full details of the 
requirements for monitoring and reporting. Notional monitoring 
locations (for biological and acoustic monitoring) are shown in Figures 
3-1 and 3-2 of the Plan. The purpose of this Plan is to provide 
protocols for acoustic and marine mammal monitoring implemented during 
pile driving and removal activities. We have preliminarily determined 
this monitoring plan, which is summarized here and which largely 
follows the monitoring strategies required and successfully implemented 
under the previous IHAs, to be sufficient to meet the MMPA's monitoring 
and reporting requirements. The previous monitoring plan was modified 
to integrate adaptive changes to the monitoring methodologies as well 
as updates to the scheduled construction activities. Monitoring 
objectives are as follows:
     Monitor in-water construction activities, including the 
implementation of in-situ acoustic monitoring efforts to continue to 
measure SPLs from in-water construction and demolition activities not 
previously monitored or validated during the previous IHAs. This would 
include collection of acoustic data for activities and pile types for 
which sufficient data has not previously been collected, including for 
diamond saw cutting of caissons during fuel pier demolition. The Navy 
also plans to collect acoustic data for removal of 30-in steel piles 
via either vibratory extraction or torch cutting.
     Monitor marine mammal occurrence and behavior during in-
water construction activities to minimize marine mammal impacts and 
effectively document marine mammals occurring within ZOI boundaries.
    Collection of ambient underwater sound measurements in the absence 
of project activities has been concluded, as a rigorous baseline 
dataset for the project area has been developed.

Acoustic Measurements

    The primary purpose of acoustic monitoring is to empirically verify 
modeled injury and behavioral disturbance zones (defined at radial 
distances to NMFS-specified thresholds; see ``Estimated Take by 
Incidental Harassment'' below). For non-pulsed sound, distances will 
continue to be evaluated for attenuation to the point at which sound 
becomes indistinguishable from background levels. Empirical acoustic 
monitoring data will be used to document transmission loss values 
determined from past measurements and to examine site-specific 
differences in SPL and affected ZOIs on an as needed basis.
    Should monitoring results indicate it is appropriate to do so, 
marine mammal mitigation zones may be revised as necessary to encompass 
actual ZOIs. Acoustic monitoring will be conducted as specified in the 
approved Monitoring Plan. Please see Table 2-2 of the Plan for a list 
of equipment to be used during acoustic monitoring. Monitoring 
locations will be determined based on results of previous acoustic 
monitoring effort and the best professional judgment of acoustic 
technicians.
    No acoustic data will be collected for 30-in steel piles as 
sufficient data has been collected for 36-in steel piles during 
previous years. For other activities, such as fender pile driving and 
demolition, the Navy will continue to collect in situ acoustic data to 
validate source levels and ZOIs. Environmental data would be collected 
including but not limited to: Wind speed and direction, air 
temperature, humidity, surface water temperature, water depth, wave 
height, weather conditions and other factors that could contribute to 
influencing the airborne and underwater sound levels (e.g., aircraft, 
boats). Full details of acoustic monitoring requirements may be found 
in section 4.2 of the Navy's Monitoring Plan.

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 as described under ``Proposed 
Mitigation'' and in the Monitoring Plan, with observers located at the 
best practicable vantage points. Notional monitoring locations are 
shown in Figures 3-1 and 3-2 of the Navy's Plan. Please see that plan, 
available at www.nmfs.noaa.gov/pr/permits/incidental/construction.htm, 
for full details of the required marine mammal monitoring. Section 3.2 
of the Plan and section 13 of the Navy's application offer more detail 
regarding monitoring protocols. 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 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.
    One MMO will be placed in the most effective position near the 
active construction/demolition platform in order to observe the 
respective shutdown zones for vibratory and impact pile driving or for 
applicable demolition activities. Monitoring would be primarily 
dedicated to observing the shutdown zone; however, MMOs would record 
all marine mammal sightings beyond these distances provided it did not 
interfere with their effectiveness at carrying out the shutdown 
procedures. Additional land, pier, or vessel-based MMOs will be 
positioned to monitor the shutdown zones and the buffer zones, as 
notionally indicated in Figures 3-1 and 3-2 of the Navy's application.
    During driving of steel piles, at least four additional MMOs (five 
total) will be deployed. Three of the five MMOs will be positioned in 
various pier-based locations around the new fuel pier to monitor the 
ZOIs. Two of these will be stationed at the north and south ends of the 
second deck of the new pier, and one MMO will be stationed on a second 
story balcony of a building on the existing pier. This building is 
scheduled to be demolished as part of the project. When the building is 
removed, a suitable secondary location with similar visibility will be 
used as an observation location. One MMO will be positioned in a boat 
at or near floating docks associated, and will focus on the furthest 
extent of the 450-m cetacean shutdown ZOI. The fifth MMO will be 
positioned on a second-story balcony of a Navy building on Ballast 
Point at the entrance to San Diego Bay, will focus on the furthest 
extent of the Level B ZOIs, and will monitor for marine mammals as they 
enter or exit San Diego Bay.
    One additional team member--the ``Command'' position--will remain 
on the construction barge for the duration of monitoring efforts, and 
will log pile driving start and stop times. This

[[Page 52655]]

position will act as a secondary MMO during monitoring efforts, but 
will not log marine species observations as part of their normal 
duties. They will use either verbal or visual communication procedures 
to stop active construction if an animal enters the shutdown zones.
    During driving of 24 x 30-in concrete fender piles, two MMOs and 
the additional ``Command'' team member will be on duty. The two MMOs 
would be stationed on the second deck of the new fuel pier in the most 
appropriate locations. During driving of the 16-in poly-concrete pile, 
one MMO and the ``Command'' position would be on duty. One MMO would be 
on duty during demolition using the diamond saw. During activity at the 
NMAWC site, at least two MMOs will be on duty and will be located at 
the most appropriate positions.
    The MMOs will record all visible marine mammal sightings. Confirmed 
takes will be registered once the sightings data has been overlaid with 
the isopleths identified in Table 5 and visualized in Figures 6-2, 6-3, 
and 6-4 of the Navy's application, or based on refined acoustic data, 
if amendments to the ZOIs are needed. Acousticians on duty may be 
noting SPLs in real-time, but, to avoid biasing the observations, will 
not communicate that information directly to the MMOs. These platforms 
may move closer to, or farther from, the source depending on whether 
received SPLs are less than or greater than the regulatory threshold 
values. All MMOs will be in radio communication with each other so that 
the MMOs will know when to anticipate incoming marine mammal species 
and when they are tracking the same animals observed elsewhere.
    If any species for which take is not authorized is observed by a 
MMO during applicable construction or demolition activities, all 
construction will be stopped immediately. If a boat is available, MMOs 
will follow the animal(s) at a minimum distance of 100 m until the 
animal has left the Level B ZOI. Pile driving will commence if the 
animal has not been seen inside the Level B ZOI for at least one hour 
of observation. If the animal is resighted again, pile driving will be 
stopped and a boat-based MMO (if available) will follow the animal 
until it has left the Level B ZOI.
    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, and if possible, the correlation to measured 
SPLs;
     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.
    In addition, photographs would be taken of any gray whales 
observed. These photographs would be submitted to NMFS' West Coast 
Regional Office for comparison with photo-identification catalogs to 
determine whether the whale is a member of the WNP population.

Reporting

    A draft report would be submitted to NMFS within 45 calendar days 
of the completion of marine mammal monitoring, or sixty days prior to 
the issuance of any subsequent IHA for this project, 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. A final report 
would be prepared and submitted within thirty days following resolution 
of comments on the draft report. Required contents of the monitoring 
reports are described in more detail in the Navy's Acoustic and Marine 
Species Monitoring Plan.

Monitoring Results From Previously Authorized Activities

    The Navy complied with the mitigation and monitoring required under 
the previous authorizations for this project. Acoustic and marine 
mammal monitoring was implemented as required, with marine mammal 
monitoring occurring before, during, and after each pile driving event. 
During the course of Year 3 activities, the Navy did not exceed the 
take levels authorized under the IHA, and no animals were observed to 
occur within defined Level A harassment zones (please see the Navy's 
monitoring report for more details and below for further discussion).
    The general objectives of the monitoring plan were similar to those 
described above for the Year 4 monitoring plan. For acoustic 
monitoring, the primary goal was to continue to collect in situ data 
towards validation of the acoustic ZOIs defined based on previous data 
collection efforts and using the transmission loss modeling effort 
conducted prior to the start of the project, and to continue collection 
of data on background noise conditions in San Diego Bay.
    Acoustic Monitoring Results--For a full description of acoustic 
monitoring methodology, please see section 2.3 of the Navy's monitoring 
report, including Figure 2-3 for representative monitoring locations. 
Results from Years 1-3 are displayed in Table 2. Please see our notices 
of proposed IHAs for the Years 2 and 3 IHAs (79 FR 53026; September 5, 
2014 and 80 FR 53115; September 2, 2015) or the Navy's Year 1 and 2 
monitoring reports for more detailed description of monitoring 
accomplished during the first two years of the project.
    For acoustic monitoring associated with impact pile driving, 
continuous hydroacoustic monitoring systems were positioned at source 
(10 m from the pile) and opportunistically at predicted 160-dB Level B 
ZOIs. The far-field data collections were conducted at multiple 
locations during impact driving of 16-in concrete-filled poly piles and 
24 x 30-in concrete fender piles, i.e., approximately 20 to 550 m from 
source. Hydrophones were deployed from the dock, barge, or moored 
vessel at half the water depth. The SPLs for driving of 30-in steel 
pipe piles were measured intermittently and archived (but not reported) 
because associated SPLs for

[[Page 52656]]

the size, type, and location of the piles were previously validated. 
Source SPLs were recorded and analyzed for a minimum of five piles for 
each of the concrete pile types. Additional measurements were archived.
    SPLs of pile driving and demolition activities conducted during 
Year 2 fell within expected levels but varied spatially relative to the 
existing fuel pier structure and maximum source levels for individual 
piles (Table 4). For both vibratory and impact pile driving methods, 
results from the IPP (Year 1) and 2014/2015 production pile driving 
(Year 2) showed that transmission loss for piles driven in shallow 
water inside of the existing fuel pier was greater than piles driven in 
deep water outside of the existing pier. Differences in depth, sediment 
type, and existing in-water pier/wharf structures likely accounted for 
variations in transmission loss and measured differences in SPLs 
recorded at the shutdown and far-field locations for shallow versus 
deep piles of the same type and size. SPLs documented during vibratory 
and impact pile driving of shallow and deep steel pipe piles of the 
same size displayed notable differences in SPLs at shutdown range and 
to a lesser extent at source.
    Measurements of impact driving of concrete piles conducted during 
Year 3 produced greater than expected SPLs at source. Differences in 
the subsurface conditions may account for the discrepancy, as a 
hardened layer is found at approximately 20-40 m below the mudline. 
SPLs documented during driving of 16-in piles generally displayed 
relatively low sound source levels during initial driving then 
appreciable increases observed once the piles interacted with this 
layer. Measurements from driving of the square concrete piles showed 
greatest sound source levels during initial impact pile driving which 
then decreased once the piles transitioned through the hardened layer. 
While source SPLs were observed to be greater than expected for both 
pile types, attenuation was also greater. Despite greater than expected 
source levels, the measured isopleth distances were similar to modeled 
predictions. Far-field impact pile driving results varied substantially 
between piles and locations for the various pile sizes, types, and 
locations. Both pile types were driven adjacent to the new fuel pier 
and source SPLs were subject to a wide variety of boundary conditions 
from recently driven piles and associated pier infrastructure. Further 
detail and discussion is provided in the Navy's report.

                                                          Table 2--Acoustic Monitoring Results
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                              Average     Average      Measured distances to relevant zones (dB rms/dB
                                                                 Number of  underwater   airborne                    unweighted) (m) \1\
          Location                Activity        Pile type        piles     SPL at 10  SPL at  15 -----------------------------------------------------
                                                                 measured   m (dB rms)  m (LZFmax)    120      160      180      190     90 \4\  100 \4\
--------------------------------------------------------------------------------------------------------------------------------------------------------
NMAWC.......................  Impact.........  12- and 16-in            58         182         108      n/a      126       13      <10      728      105
                                                concrete.
Fuel Pier (Year 1)..........  Vibratory......  30- and 36-in             9         167         113      \2\      n/a      <10      <10      233       71
                                                steel pipe.                                           3,000
                              Impact.........  36-in steel               7         200  ..........      n/a      \3\  \3\ 450   \3\ 75  .......  .......
                                                pipe.                                                          2,500
Fuel Pier (Year 2) \6\......  Vibratory......  30-in steel               2         165         107  .......  .......  .......  .......  .......  .......
                                                pipe.
                              Impact.........  30-in steel               2         196  ..........  .......  .......  .......  .......  .......  .......
                                                pipe.
                              Vibratory......  36-in steel              31         178  ..........    2,500      n/a      <10      <10      182       78
                                                pipe.
                              Impact.........  36-in steel              31         204  ..........      n/a    2,000      350       75  .......  .......
                                                pipe.
Hydraulic cutting...........  24-in concrete.  4..............         154  ..........  ..........  .......  .......  .......  .......  .......  .......
                              Diamond saw      72-in caisson..           4     \5\ 143  ..........  .......  .......  .......  .......  .......  .......
                               cutting.
Fuel Pier (Year 3) \7\......  Impact.........  16-in poly-               6         190     104-110  .......      270       50       20      149       42
                                                concrete.
                              Impact.........  24 x 30-in                3         189     110-113  .......      470  .......  .......  .......  .......
                                                concrete.
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Site-specific measured transmission loss values (both underwater and airborne) were used to calculate zone distances. See monitoring report for more
  detail.
\2\ The 120-dB disturbance zone was initially modeled to be 6,470 m; however, ambient sound in the vicinity of the project site was measured at
  approximately 128 dB rms (see below). This value was used in conjunction with a site-specific propagation model to arrive at a predicted distance of
  3,000 m at which sound should attenuate to background levels. This was supported by collection of measured dB rms values for vibratory pile driving
  during the IPP, as signal could not be distinguished from background at similar distance.
\3\ These values are for outside piles. Measured distances to the 160/180/190 dB ZOIs for inside piles were 2,000/100/40 m. Zones calculated on the
  basis of SPLs from 36-in piles.
\4\ Distances based on impact driving.
\5\ Value measured at 15 m from source.
\6\ Year 2 values are maximum values rather than average. We use these in defining conservative ZOIs.
\7\ Underwater source level measurements are as reported from Loggerhead DSG acoustic data recorders and described in section 3.2.2 and Appendix E of
  the report.

    Ambient data collection was conducted in a manner consistent with 
NMFS' 2012 guidance for measurement of background sound. Ambient 
underwater and airborne sound level recordings were collected for three 
eight-hour days in December 2015, and April and May 2016. Ambient sound 
level recordings were collected in the absence of construction 
activities, and during typical construction time periods (7 a.m. to 6 
p.m.), at locations that were between 400 and 750 m from each site. 
Sites were chosen to minimize boat traffic effects that might impact 
results. Data recorded during December 2015 and on April 5, 2016, were 
determined to be outliers due to anthropogenic corruption. The 
resulting median ambient SPL was 130.5 dB rms, similar to the value of 
approximately 128 dB rms resulting from previous measurement efforts.
    Marine Mammal Monitoring Results--Marine mammal monitoring was 
conducted as required under the IHA and as described in the Year 3 
monitoring plan and in our Federal Register notice of proposed 
authorization associated with the Year 3 IHA. For a full description of 
monitoring methodology, please see section 2.4 of the Navy's monitoring 
report, including Figures 2-1 and 2-2 for representative monitoring 
locations and Figures 2-4, 2-5, and 2-6 for monitoring zones. 
Monitoring protocols were managed adaptively during the course of the 
third-year IHA. Multiple shutdowns were implemented due to marine 
mammals being observed within buffered shutdown zones, but no animals 
were observed within actual predicted Level A harassment zones.
    Monitoring results are presented in Table 3. The Navy recorded all 
observations of marine mammals, including pre- and post-construction

[[Page 52657]]

monitoring efforts. Animals observed during these periods or that were 
determined to be outside relevant ZOIs were not considered to represent 
incidents of take. Please see Figures 3-13, 3-19, and 3-24 for 
locations of observations and incidents of take relative to the project 
sites. Take authorization for the second-year authorization was 
informed by an assumption that 115 days of in-water construction would 
occur, whereas only fifty total days actually occurred. However, the 
actual observed rates per day were in all cases lower than what was 
assumed. Therefore, we expect that the Navy would not have exceeded the 
take allowances even if the full 115 days had been reached. In addition 
to the results shown in Table 3, the Navy observed two unidentified 
pinnipeds, which were likely California sea lions. These were not 
within an active Level B harassment zone.
    There were considerably fewer individuals and sightings during the 
Year 3 IHA when compared to the same months during the Year 2 IHA, and 
only three species were observed. This may be due to environmental 
fluctuations as part of the on-going El Ni[ntilde]o event. Water 
temperatures during Year 3 were cooler than during the same months 
during Year 2. Although the temperatures were still higher than the 
average water temperatures for the region prior to the current El 
Ni[ntilde]o event, it shows that the event may have been dissipating. 
In addition, California sea lion strandings decreased. No evidently 
significant behavioral changes were reported.
    There was one sighting of a dead California sea lion in the 
vicinity of the project. The dead animal was evaluated and deemed as 
having died as a result of factors unrelated to the project, likely due 
to the unusual mortality event currently ongoing in southern California 
waters. The observation was appropriately reported in accordance with 
the IHA and per protocols agreed-upon with NMFS' regional stranding 
coordinator.

                                    Table 3--Marine Mammal Monitoring Results
----------------------------------------------------------------------------------------------------------------
                                                                                   Extrapolated
                                       Total           Total         Observed      incidents of        Total
             Species                 sightings      individuals    incidents of    Level B take      estimated
                                                                   Level B take         \1\        Level B take
----------------------------------------------------------------------------------------------------------------
California sea lion.............             331             411              97              96             193
Harbor seal.....................              24              24               9               7              16
Bottlenose dolphin..............              13              25               2               3               5
----------------------------------------------------------------------------------------------------------------
\1\ Assumed density and unmonitored area of assumed Level B ZOI used with actual pile driving time to generate
  assumed take for unmonitored areas.

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 or demolition and involving temporary 
changes in behavior. The proposed mitigation and monitoring measures 
(i.e., buffered shutdown zones) are expected to minimize the 
possibility of Level A harassment such that we believe it is unlikely. 
We do not expect that injurious or lethal takes would occur even in the 
absence of the planned mitigation and monitoring measures.
    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 (with the exception of California sea lions, which are 
attracted to nearby haul-out opportunities). Sightings of other species 
are relatively 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 potential taking of 
small numbers of California sea lions, harbor seals, bottlenose 
dolphins, common dolphins, Pacific white-sided dolphins, Risso's 
dolphins, northern elephant seals, and gray whales in San Diego Bay and 
nearby waters that may result from pile driving during construction 
activities associated with the fuel pier replacement project described 
previously in this document. In order to estimate the potential 
incidents of take that may occur incidental to the specified activity, 
we typically 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. In this case, we have acoustic data from project monitoring that 
provides empirical information regarding the sound fields likely 
produced by project activities. We first provide information on 
applicable sound thresholds for determining effects to marine mammals 
before describing the measured sound fields, the available marine 
mammal density or abundance information, and the method of estimating 
potential incidents of take.

[[Page 52658]]

Sound Thresholds

    We have historically used generic sound exposure thresholds (see 
Table 4) to determine when an activity that produces sound might result 
in impacts to a marine mammal such that a take by harassment might 
occur. These thresholds should be considered guidelines for estimating 
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. However, NOAA is currently developing new guidance for 
acoustic injury (equating to Level A harassment under the MMPA); for 
more information on that process, please visit www.nmfs.noaa.gov/pr/acoustics/guidelines.htm.

               Table 4--Current Acoustic Exposure Criteria
------------------------------------------------------------------------
            Criterion                 Definition           Threshold
------------------------------------------------------------------------
Level A harassment (underwater).  Injury (PTS--any    180 dB (cetaceans)/
                                   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

    Background information on underwater sound propagation and the 
calculation of range to relevant thresholds was provided in our Federal 
Register notice of proposed authorization associated with the first-
year IHA (78 FR 30873; May 23, 2013). For the first-year IHA, the Navy 
estimated sound fields using a site-specific model for transmission 
loss (TL) from pile driving at a central point at the project site in 
combination with proxy source levels (as described in the 
aforementioned Federal Register notice). The model is based on 
historical temperature-salinity data and location-dependent bathymetry. 
In the model, TL is the same for different sound source levels and is 
applied to each of the different activities to determine the point at 
which the applicable thresholds are reached as a function of distance 
from the source. The model's predictions result in a slightly lower 
average rate of TL than practical spreading, and hence are 
conservative. The model has been further validated using acoustic 
monitoring data collected during the first three IHAs (see Figure 6-1 
of the Navy's application). For activities conducted at the NMAWC site, 
practical spreading loss (15 log[distance/10]) is assumed.
    Impact and vibratory driving of steel pipe piles, impact driving of 
concrete and concrete-filled fiberglass piles, and demolition using 
different techniques (including diamond saw cutting and potentially 
vibratory removal) is planned for the next phase of work. Acoustic 
monitoring results that inform both the take estimates as well as the 
mitigation monitoring zones were reported in Table 2. Here, we present 
the calculated distances for predicted Level A and Level B ZOIs (Table 
5). In some cases, the predicted zones have been modified for purposes 
of mitigation and/or monitoring implementation by adding buffers or by 
retaining a more conservative zone size based on prior assumptions. In 
all cases, proposed mitigation and/or monitoring zones are either 
equivalent to or larger than those indicated by relevant in situ data 
collection. See also Figures 6-2, 6-3, and 6-4 of the Navy's 
application for visual representation of the anticipated sound fields 
and their interaction with local topography.
    Measured source levels for impact and vibratory driving of 30-in 
steel piles were 196 dB rms and 165 dB rms, respectively, but were 
based on only two measured piles. Here we use measured values for 36-in 
steel piles (204 dB rms and 174 dB rms) as conservative proxies. 
Background sound has been determined to be approximately 128 dB rms, 
and the distance at which continuous sound produced by vibratory 
driving would attenuate to background levels has been determined to be 
approximately 3,000 m. Although Year 2 measurements indicate that such 
attenuation may occur closer to 2,500 m, we conservatively retain the 
larger distance for estimating exposures. We conservatively use the 
vibratory pile installation value as proxy for vibratory pile removal, 
if it occurs.
    For the two types of concrete fender piles, measured values from 
Year 3 acoustic monitoring are louder than might be expected from other 
available literature. We had previously assumed values of 176 dB rms 
and 173 dB rms for impact driving of 24 x 30-in concrete piles and 16-
in concrete piles, respectively (Caltrans, 2012), but the Navy's 
acoustic monitoring program showed that these proxies were too low (see 
Table 3-2 and Appendix E of the Navy's monitoring report). The Navy 
proposed to conservatively use average maximum rms SPLs for these piles 
(see Table 6-4 of the Navy's application), i.e., 192 dB rms and 194 dB 
rms, respectively. However, as discussed previously acoustic monitoring 
results showed measured isopleth distances roughly comparable to those 
previously predicted. We use those values (Table 5) for exposure 
calculations here. Demolition via diamond saw cutting is based on 
limited demolition measurements collected during Year 2 monitoring 
(maximum rms SPLs ranging from 152-155 dB rms), resulting in a 
conservative maximum assumed source level of 155 dB rms. For use of the 
diamond saw and for vibratory extraction of piles at NMAWC, practical 
spreading loss was assumed and distances were estimated to the assumed 
background sound level of 128 dB. Continued acoustic monitoring will 
target impact driving of concrete piles and use of the diamond saw. 
Please see Tables 6-4 and 6-5 in the Navy's application for more 
detail.

[[Page 52659]]



                                                        Table 5--Distances to Relevant Thresholds
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                          Distance to threshold in meters
                        Activity                         -----------------------------------------------------------------------------------------------
                                                              190 dB          180 dB          160 dB          120 dB          100 dB           90 dB
--------------------------------------------------------------------------------------------------------------------------------------------------------
Impact driving, 30-in steel piles \1\...................          \1\ 75         \1\ 350           2,000             n/a              80             233
Vibratory driving, 30-in steel piles....................         \2\ <10             <10             n/a           3,000  ..............  ..............
Impact driving, 24 x 30 concrete piles..................              20              50             470             n/a              42             149
Impact driving, 16-in concrete-filled fiberglass piles..              20              50             270             n/a  ..............  ..............
Impact driving, 16-in concrete piles (NMAWC)............             <10             <10             126             n/a             105             728
Vibratory extraction, 16-in concrete piles (NMAWC)......             <10             <10             n/a             631  ..............  ..............
Diamond saw cutting (demolition)........................             <10             <10             n/a             631  ..............  ..............
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ The buffered zones for use in mitigation will be 150 m and 450 m, respectively.
\2\ The minimum shutdown zone for all activities is 10 m.

Airborne Sound

    Although sea lions are known to haul-out regularly on man-made 
objects in the vicinity of the project site (see Figure 4-1 of the 
Navy's application), and harbor seals are occasionally observed hauled 
out on rocks along the shoreline in the vicinity of the project site, 
none of these are within the ZOIs for airborne sound, and we believe 
that incidents of take resulting solely from airborne sound are 
unlikely. The zones for sea lions are within the minimum shutdown zone 
defined for underwater sound and, although the zones for harbor seals 
are larger, they have not been observed to haul out as readily on man-
made structure in the immediate vicinity of the project site. There is 
a 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.
    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. Distances 
associated with airborne sound and shown in Table 5 are for reference 
only.

Marine Mammal Densities

    For all species, the best scientific information available was 
considered for use in the marine mammal take assessment calculations. 
Although various regional offshore surveys for marine mammals have been 
conducted, it is unlikely that these data would be representative of 
the species or numbers that may be encountered in San Diego Bay. 
However, the Navy has conducted a large number of ongoing site-specific 
marine mammal surveys during appropriate seasons (e.g., Merkel and 
Associates, 2008; Johnson, 2010, 2011; Lerma, 2012, 2014). Whereas 
analyses for the first-year IHA relied on surveys conducted from 2007-
12, continuing surveys by the Navy have generally indicated increasing 
abundance of all species and the second-year IHA relied on 2012-14 
survey data. In addition, the Navy has developed estimates of marine 
mammal densities in waters associated with training and testing areas 
(including Hawaii-Southern California) 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 based upon the best available information, except 
where specific local abundance information is available and applicable 
to a specific action area. The document is publicly available on the 
Internet at: nwtteis.com/DocumentsandReferences/NWTTDocuments/SupportingTechnicalDocuments.aspx (accessed July 27, 2016).
    Year 2 project monitoring showed even greater abundance of certain 
species, and we consider all of these data in order to provide the most 
up-to-date estimates for marine mammal abundances during the period of 
this proposed IHA. Although Year 3 project monitoring showed declines 
in marine mammal abundance in the vicinity of the project, we retain 
prior density estimates as a conservative measure for estimating 
exposure. Density information is shown in Table 7. These data are from 
dedicated line-transect surveys, required project marine mammal 
monitoring, opportunistic observations for more rarely observed species 
(see Figures 3-1 through 3-5 of the Navy's application), or the NMSDD.

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;
     The assumed ZOIs and days of activity are as shown in 
Table 6; and,
     Exposures to sound levels at or above the relevant 
thresholds equate to take, as defined by the MMPA.
    In this case, the estimation of marine mammal takes 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.

    The ZOI impact area is estimated using the relevant distances in 
Table 5, assuming that sound radiates from a central point in the water 
column slightly offshore of the existing pier and

[[Page 52660]]

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.

        Table 6--Areas of Acoustic Influence and Days of Activity
------------------------------------------------------------------------
                Activity                  Number of days    ZOI (km\2\)
------------------------------------------------------------------------
Impact and vibratory driving, 30-in                   24          5.6752
 steel piles \1\........................
Vibratory removal, 30-in steel piles....               6          5.6752
Impact driving, 24 x 32-in concrete                   28          0.5377
 piles..................................
Impact driving, 16-in concrete-filled                  1          0.2180
 fiberglass piles.......................
Diamond saw cutting.....................              69          0.8842
Impact driving, 16-in concrete piles                  10          0.0436
 (NMAWC)................................
Vibratory removal, 16-in concrete piles                8          2.7913
 (NMAWC)................................
------------------------------------------------------------------------
\1\ We assume that impact driving of 30-in steel piles would always
  occur on the same day as vibratory driving of the same piles.
  Therefore, the impact driving ZOI (3.8894 km\2\) would always be
  subsumed by the vibratory driving ZOI.

    Where appropriate, we use average daily number of individuals 
observed within the project area during Navy marine mammal surveys 
converted to a density value by using the largest ZOI as the effective 
observation area. It is the opinion of the professional biologists who 
conducted these surveys that detectability of animals during these 
surveys, at slow speeds and under calm weather and excellent viewing 
conditions, approached one hundred percent.
    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 (aside from 
the contingency correction discussed above). 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 period of validity, 
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 7 for total estimated incidents of take.

California Sea Lion

    The NMSDD reports estimated densities for north and central San 
Diego Bay of 5.8 animals/km\2\ for the summer and fall periods and 2.5 
animals/km\2\ during the winter and spring (based on surveys conducted 
2007-11; note that the NMSDD does not present density estimates 
specific to San Diego Bay for other species). For the first-year IHA, 
the Navy reported an average abundance of approximately sixty 
individuals per survey day (approximately equating to the reported 
density). However, Year 2 project monitoring showed an average of 90.35 
individuals per day occurring within the project area (i.e., 5.6752 
km\2\). This includes both hauled-out and swimming individuals. For 
California sea lions, the most common species in northern San Diego Bay 
and the only species with regular occurrence in the project area, we 
determined that this value--derived from the most recent monitoring 
effort--would be appropriate for use in estimating potential incidents 
of take.

Harbor Seal

    Harbor seals are relatively uncommon within San Diego Bay. 
Previously, sightings in the Navy transect surveys of northern San 
Diego Bay were limited to individuals outside of the ZOI, on the south 
side of Ballast Point. These individuals had not been observed entering 
or transiting the project area and were believed to move from this 
location to haul-outs further north at La Jolla. Separately, marine 
mammal monitoring conducted by the Navy intermittently from 2010-14 had 
documented up to four harbor seals near Pier 122 (within the ZOI) at 
various times, with the greatest number of sightings during April and 
May. This information was used in previous IHA analysis, wherein we 
assumed that three harbor seals could be present for up to thirty days 
of the project. However, Year 2 project monitoring indicated an average 
abundance of 2.83 individuals per day in the project area. Animals were 
seen swimming as well as hauled out on rocks along the shoreline of 
NBPL. Although it is unknown whether this increase in abundance is a 
temporary phenomenon we use this new information on a precautionary 
basis as the best available information, and assume that this number of 
animals could be present on any day of the project. The NMSDD provides 
a maximum density estimate of 0.02 animals/km\2\ for southern 
California, but site-specific information indicates that harbor seals 
are more common within the northern San Diego Bay project area than 
this density would suggest.

Gray Whale

    The NMSDD provides a density of 0.115 animals/km\2\ for southern 
California waters from shore to 5 nm west of the Channel Islands 
(winter/spring only; density assumed to be zero during summer/fall), a 
value initially reported by Carretta et al. (2000) for gray whales 
around San Clemente Island in the Southern California Bight. Gray 
whales were seen only from January-April. In the project area, 
observational data for gray whales is limited and their occurrence 
considered infrequent and unpredictable. On the basis of limited 
information--in recent years, solitary individuals have entered the bay 
and remained for varying lengths of time in 2009, 2010, 2011, and 2014, 
and whales more regularly transit briefly past the mouth of San Diego 
Bay--we assume here that the NMSDD density is applicable, while 
acknowledging that it likely represents a precautionary estimate for 
waters within the Bay as

[[Page 52661]]

opposed to those outside the mouth of the bay that whales are more 
likely to transit through. Incidental harassment of gray whales could 
result from some combination of individuals briefly transiting near the 
mouth of the bay and from individuals entering the bay and lingering in 
the project area.

Bottlenose Dolphin

    Coastal bottlenose dolphins can occur at any time of year in San 
Diego Bay. Numbers sighted during Navy transect surveys have been 
highly variable, ranging from zero to forty individuals (observed 
dolphins are assumed to have been of the coastal stock). An uncorrected 
average of 2.1 bottlenose dolphins was observed during recent Navy 
surveys (September 2012 through April 2014), although nineteen animals 
were observed in a single survey. As reported in the NMSDD, Dudzik et 
al. (2006) provide a uniform density for California coastal dolphins of 
0.4 animals/km\2\ within 1 km of the coast from Baja to San Francisco 
in all four seasons. However, given the high variability observed in 
terms of numbers and locations of bottlenose dolphin sightings, we 
believe it appropriate to take a precautionary approach to take 
estimation use Year 2 sightings (7.09 individuals per day) as the basis 
for a density value.

Common Dolphin

    Common dolphins are present in the coastal waters outside of San 
Diego Bay, but have typically been observed in the bay only 
infrequently and were never seen during the Navy's surveys. However, 
the previously described observations of common dolphins in the project 
area during in 2014 prompted their inclusion in the second IHA, a 
decision supported by increased observations of common dolphins during 
Year 2. There have not been enough sightings of common dolphins in San 
Diego Bay to develop a reliable estimate specific to the project area. 
Sightings of long-beaked common dolphins are predominantly near shore, 
and have been documented during Navy training exercises just offshore 
and to the south of San Diego Bay, whereas those of short-beaked common 
dolphins extend throughout the coastal and offshore waters. The NMSDD 
provides an all-season density estimate of 0.1 animals/km\2\ for the 
long-beaked common dolphin within southern California waters (derived 
from Ferguson and Barlow [2003] and Barlow and Forney [2007]). However, 
given the large numbers of dolphins and increasing observations during 
2014-15, we use the sighting rate of 8.67 dolphins per day as the basis 
for a density value. Although short-beaked common dolphins are less 
common in nearshore waters than are long-beaked, and are expected to be 
less likely to occur in the project area, we assign a single value to 
all common dolphins that may occur in the project area. Any incidents 
of take could be of either long-beaked or short-beaked common dolphins.

Pacific White-Sided Dolphin

    Pacific white-sided dolphins are not known from the project area, 
but were observed in the bay on several occasions during Year 2 
monitoring (0.28 individuals per day). This information produces a 
density estimate slightly lower than that found in Hanser et al. 
(2015), and is the only information available for use in estimating 
potential exposures.

Risso's Dolphin

    Although no Risso's dolphins have not been observed in the project 
area, they are one of the more common species known from deeper waters 
nearby. Therefore, we use the regional density estimate from Hanser et 
al. (2015) in estimating potential exposures.

Northern Elephant Seal

    Only one elephant seal has been observed in the project area, but 
given the increasing regional abundances for this species, we believe 
it reasonable to propose take authorization, and the regional density 
estimate found in Hanser et al. (2015) is used here. It is unlikely 
that elephant seals would haul out on any structures within the 
airborne ZOIs, and we do not consider harassment via airborne noise as 
a possibility for this species.

                                                  Table 7--Calculations for Incidental Take Estimation
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                Impact
                                                    Vibratory      Impact      driving,                   Impact     Vibratory        Total proposed
               Species                  Density      driving/     driving,    concrete/   Diamond saw    driving,     removal,    authorized takes (% of
                                                     removal,   concrete 24   fiberglass                 concrete     concrete         total stock)
                                                    steel \1\       x 30        16-in                    (NMAWC)      (NMAWC)
--------------------------------------------------------------------------------------------------------------------------------------------------------
California sea lion.................      15.9201        2,710          240            3          971            7          113  4,044 (1.4).
Harbor seal.........................       0.4987           85            8            0           30            0            4  127 (0.4).
Bottlenose dolphin..................       1.2493          213           19            0           76            1            9  318 (64.0).\2\
Common dolphin......................       1.5277          260           23            0           93            1           11  388 (0.4 [LB]/0.1
                                                                                                                                  [SB]).\3\
Gray whale..........................        0.115           20            2            0            7            0            1  30 (0.1).
Northern elephant seal..............       0.0508            9            1            0            3            0            0  13 (0.01).
Pacific white-sided dolphin.........       0.0493            8            1            0            3            0            0  12 (0.04).
Risso's dolphin.....................       0.2029           35            3            0           12            0            1  51 (0.8).
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ We assume that impact driving of steel piles would occur on the same day as vibratory driving of the same piles and that the zone for vibratory
  driving would always subsume the zone for impact driving. Therefore, separate estimates are not provided for impact driving of steel piles.
\2\ Total stock assumed to be 500 for purposes of calculation. See Table 1.
\3\ LB = long-beaked; SB = short-beaked.


[[Page 52662]]

Analyses and Preliminary Determinations

Negligible Impact Analysis

    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 
(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.
    Construction and demolition activities associated with the pier 
replacement project, 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 or removal 
is happening.
    No injury, serious injury, or mortality is anticipated given the 
nature of the activity 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. For example, use of 
vibratory hammers does not have significant potential to cause injury 
to marine mammals due to the relatively low source levels produced and 
the lack of potentially injurious source characteristics. Impact pile 
driving produces short, sharp pulses with higher peak levels and much 
sharper rise time to reach those peaks. When impact driving is 
necessary, required measures (implementation of buffered shutdown 
zones) significantly reduce 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. The likelihood that marine 
mammal detection ability by trained observers is high under the 
environmental conditions described for San Diego Bay (approaching one 
hundred percent detection rate, as described by trained biologists 
conducting site-specific surveys) further enables the implementation of 
shutdowns to avoid injury, serious injury, or mortality.
    Effects on individuals that are taken by Level B harassment, on the 
basis of reports in the literature as well as monitoring from past 
years of this project and 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, 2012; Lerma, 2014). 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. In response to vibratory driving, pinnipeds (which 
may become somewhat habituated to human activity in industrial or urban 
waterways) have been observed to orient towards and sometimes move 
towards the sound. 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 
fitness 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 project area while the activity is occurring.
    In summary, this negligible impact analysis is 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; and (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 activity will have only short-term 
effects on individuals. The specified activity is not expected to 
impact rates of recruitment or survival and will therefore not result 
in population-level impacts. 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 Navy's pier replacement activities 
will have a negligible impact on the affected marine mammal species or 
stocks.

Small Numbers Analysis

    The number of incidents of take proposed for authorization for 
these stocks, with the exception of the coastal bottlenose dolphin (see 
below), would be considered small relative to the relevant stocks or 
populations (see Table 7) even if each estimated taking occurred to a 
new individual. This is an extremely unlikely scenario as, for 
pinnipeds occurring at the NBPL waterfront, there will almost certainly 
be some overlap in individuals present day-to-day and in general, there 
is likely to be some overlap in individuals present day-to-day for 
animals in estuarine/inland waters.
    The proposed numbers of authorized take for bottlenose dolphins are 
higher relative to the total stock abundance estimate and would not 
represent small numbers if a significant portion of the take was for a 
new individual. However, these numbers represent the estimated 
incidents of take, not the number of individuals taken. That is, it is 
likely that a relatively small subset of California coastal bottlenose 
dolphins would be incidentally harassed by project activities. 
California coastal bottlenose dolphins range from San Francisco Bay to 
San Diego (and south

[[Page 52663]]

into Mexico) and the specified activity would be stationary within an 
enclosed water body that is not recognized as an area of any special 
significance for coastal bottlenose dolphins (and is therefore not an 
area of dolphin aggregation, as evident in Navy observational records). 
We therefore believe that the estimated numbers of takes, were they to 
occur, likely represent repeated exposures of a much smaller number of 
bottlenose dolphins and that, based on the limited region of exposure 
in comparison with the known distribution of the coastal bottlenose 
dolphin, these estimated incidents of take represent small numbers of 
bottlenose dolphins.
    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 this action. Therefore, 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)

    The Navy initiated informal consultation under section 7 of the ESA 
with NMFS Southwest Regional Office (now West Coast Regional Office) on 
March 5, 2013. NMFS concluded on May 16, 2013, that the proposed action 
may affect, but is not likely to adversely affect, WNP gray whales. The 
Navy has not requested authorization of the incidental take of WNP gray 
whales and no such authorization is proposed, and there are no other 
ESA-listed marine mammals found in the action area. Therefore, no 
consultation under the ESA is required.

National Environmental Policy Act (NEPA)

    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 replacement 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 July 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 IHAs. 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 the existing EA and FONSI provide adequate 
analysis related to the potential environmental effects of issuing an 
IHA to the Navy. The 2013 NEPA documents are available for review at 
www.nmfs.noaa.gov/pr/permits/incidental/construction.htm.

Proposed Authorization

    As a result of these preliminary determinations, we propose to 
issue an IHA to the Navy for conducting the described pier replacement 
activities in San Diego Bay, for a period of one year from the date of 
issuance, provided the previously mentioned mitigation, monitoring, and 
reporting requirements are incorporated. The proposed IHA language is 
provided next.
    This section contains a draft of the IHA itself. The wording 
contained in this section is proposed for inclusion in the IHA (if 
issued).
    1. This Incidental Harassment Authorization (IHA) is valid from 
October 8, 2016, through October 7, 2017.
    2. This IHA is valid only for pile driving and removal activities 
associated with the fuel pier replacement project in San Diego Bay, 
California.
    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 richardii), California sea lion (Zalophus californianus), 
bottlenose dolphin (Tursiops truncatus truncatus), common dolphin 
(Delphinus delphis), northern elephant seal (Mirounga angustirostris), 
Pacific white-sided dolphin (Lagenorhynchus obliquidens), Risso's 
dolphin (Grampus griseus), and gray whale (Eschrichtius robustus).
    (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.............................................             118
California sea lion.....................................           3,757
Northern elephant seal..................................              12
California coastal bottlenose dolphin...................             295
Pacific white-sided dolphin.............................              12
Risso's dolphin.........................................              48
Common dolphin..........................................             361
Gray whale..............................................              27
------------------------------------------------------------------------

    (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. 
See Table 2 for minimum radial distances required for shutdown zones.

[[Page 52664]]



    Table 2--Radial Distance to Shutdown and Disturbance Zones Associated With Relevant Thresholds, Including
                                                     Buffers
----------------------------------------------------------------------------------------------------------------
                                                                  Distance to threshold in meters
                    Activity                     ---------------------------------------------------------------
                                                      190 dB          180 dB          160 dB          120 dB
----------------------------------------------------------------------------------------------------------------
Impact driving, steel piles.....................             150             450           2,000             n/a
Vibratory driving/removal, steel piles..........              10              10             n/a           3,000
Impact driving, concrete piles..................              40             100             470             n/a
Impact driving, concrete/fiberglass piles.......              40             100             270             n/a
Diamond saw cutting.............................              10              10             n/a             400
Impact driving, concrete piles (NMAWC)..........              10              10             130             n/a
Vibratory removal, concrete piles (NMAWC).......              10              10             n/a           2,160
----------------------------------------------------------------------------------------------------------------

    (b) The Navy shall shutdown activity as appropriate upon 
observation of any species for which take is not authorized. Activity 
shall not be resumed until those species have been observed to leave 
the relevant zone or until one hour has elapsed.
    (c) The Navy shall deploy marine mammal observers as described 
below and as indicated in the Acoustic and Marine Species Monitoring 
Plan (Monitoring Plan; attached).
    i. For all pile driving and applicable demolition activities, a 
minimum of one observer shall be stationed at the active pile driving 
rig in order to monitor the shutdown zones.
    ii. For pile driving of 30-in steel piles, at least four additional 
observers shall be positioned for optimal monitoring of the surrounding 
waters. During impact driving of steel piles, one of these shall be 
stationed for optimal monitoring of the cetacean Level A injury zone 
(see Table 2), while others may be positioned at the discretion of the 
Navy for optimal fulfillment of both acoustic monitoring objectives and 
monitoring of the Level B harassment zone. During all other pile 
driving, at least one additional observer shall be deployed and may be 
positioned at the discretion of the Navy for optimal fulfillment of 
both acoustic monitoring objectives and monitoring of the Level B 
harassment zone.
    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. Photographs 
must be taken of any observed gray whales.
    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).
    (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 impact pile driving. 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 impact pile driving and at any time following cessation of 
impact 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.
    (c) The Navy shall conduct acoustic monitoring for representative 
scenarios of pile driving activity, 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 calendar 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

[[Page 52665]]

number of incidences of take, such as ability to track groups or 
individuals.
    iii. Results of acoustic monitoring, including the information 
described in in the Monitoring Plan.
    (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 (301-427-8425), NMFS, and 
the West Coast Regional Stranding Coordinator (206-526-6550), 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.
    i. 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.
    ii. 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 analysis, the draft authorization, and 
any other aspect of this Notice of Proposed IHA for Navy's pier 
replacement 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: August 4, 2016.
Donna S. Wieting,
Director, Office of Protected Resources, National Marine Fisheries 
Service.
[FR Doc. 2016-18847 Filed 8-8-16; 8:45 am]
 BILLING CODE 3510-22-P