[Federal Register Volume 81, Number 143 (Tuesday, July 26, 2016)]
[Notices]
[Pages 48745-48762]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2016-17617]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

RIN 0648-XE671


Taking of Marine Mammals Incidental to Specified Activities; 
Construction of the East Span of the San Francisco-Oakland Bay Bridge

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

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

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SUMMARY: NMFS has received a request from the California Department of 
Transportation (CALTRANS) for an incidental take authorization to take 
small numbers of seven species of marine mammals, by harassment, 
incidental to construction activities associated with the East Span of 
the San Francisco-Oakland Bay Bridge (SFOBB) in the San Francisco Bay 
(SFB), California. Pursuant to the Marine Mammal Protection Act (MMPA), 
NMFS is requesting comments on its proposal to issue an authorization 
to CALTRANS to incidentally take, by harassment, small numbers of 
marine mammals for a period of 1 year.

DATES: Comments and information must be received no later than August 
25, 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, 1315 East-West Highway, 
Silver Spring, MD 20910. The mailbox address for providing email 
comments is [email protected]. NMFS is not responsible for email 
comments sent to addresses other than the one provided here. Comments 
sent via email, including all attachments, must not exceed a 25-
megabyte file size.
    Instructions: All comments received are a part of the public record 
and will generally be posted to http://www.nmfs.noaa.gov/pr/permits/incidental.htm without change. All Personal Identifying Information 
(for example, name, address, etc.) voluntarily submitted by the 
commenter may be publicly accessible. Do not submit Confidential 
Business Information or otherwise sensitive or protected information.
    A copy of the application may be obtained by writing to the address 
specified above or visiting the internet at: http://www.nmfs.noaa.gov/pr/permits/incidental.htm. Documents cited in this notice may also be 
viewed, by appointment, during regular business hours, at the 
aforementioned address.

FOR FURTHER INFORMATION CONTACT: Shane Guan, Office of Protected 
Resources, NMFS, (301) 427-8401.

SUPPLEMENTARY INFORMATION:

Background

    Sections 101(a)(5)(A) and (D) of the MMPA (16 U.S.C. 1361 et seq.) 
direct

[[Page 48746]]

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.
    An 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 a one-year authorization to 
incidentally take small numbers of marine mammals by harassment, 
provided that there is no potential for serious injury or mortality to 
result from the activity. 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.

Summary of Request

    On March 11, 2016, CALTRANS submitted a request to NMFS for the 
potential harassment of a small number of marine mammals incidental to 
the dismantling of the East Span of the original SFOBB in SFB, 
California, between July 16, 2016, and July 15, 2017. On May 16, 2016, 
CALTRANS submitted a revision of its IHA application based on NMFS 
comments. NMFS determined that the IHA application was complete on May 
19, 2016. NMFS is proposing to authorize the Level B harassment of 
Pacific harbor seal, California sea lion, northern elephant seal, 
northern fur seal, harbor porpoise, gray whale and bottlenose dolphin.

Description of the Specified Activity

Overview

    CALTRANS proposes removal of the East Span of the original SFOBB by 
mechanical dismantling and by use of controlled charges to implode the 
pier into its open cellular chambers below mudline. Activities 
associated with dismantling the original East Span potentially may 
result in incidental take of marine mammals. These activities include 
vibratory pile driving, vibratory pile extraction/removal, impact pile 
driving, and the use of highly controlled charges to dismantle the Pier 
E4 and Pier E5 marine foundations.
    A one-year IHA was previously issued to CALTRANS for pile driving/
removal and mechanical dismantling activities on July 17, 2015 (80 FR 
43710; July 23, 2015), based on activities described on CALTRANS' IHA 
application dated April 13, 2013. This IHA is valid until July 16, 
2016. On September 9, 2015, NMFS issued another IHA to CALTRANS for 
demolition of Pier E3 of the original SFOBB by highly controlled 
explosives (80 FR 57584; September 24, 2015). This IHA expired on 
December 30, 2015. Since the construction activities related with the 
original SFOBB dismantling will last for another two years, CALTRANS is 
requesting an IHA that covers take of marine mammals from both pile 
driving/removal and confined explosion.
    Construction activities for the replacement of the SFOBB east span 
commenced in 2002 and are expected to be completed in 2016 with the 
completion of the bike/pedestrian path and eastbound on ramp from Yerba 
Buena Island. The new east span is now open to traffic. On November 10, 
2003, NMFS issued the first project-related IHA to CALTRANS, 
authorizing the take of small numbers of marine mammals incidental to 
the construction of the SFOBB Project. Over the years, CALTRANS has 
been issued a total of nine IHAs for the SFOBB Project to date, 
excluding the application currently under review.

Dates and Duration

    The demolition of Piers E4 and E5 through controlled implosion are 
planned to occur in October, November, or December 2016, and pile 
driving and pile removal activities may occur at any time of the year. 
CALTRANS is requesting issuance of an IHA for a period of 1 year. To 
avoid a gap in IHA coverage, CALTRANS is requesting issuance of a new 
IHA no later than July 17, 2016. However, NMFS does not consider it 
feasible to issue an IHA by July 2016, and has notified CALTRANS that 
an IHA, if issued, would cover the period from August 2016 through 
August 2017.

Specified Geographic Region

    The SFOBB project area is located in the central San Francisco Bay 
(SFB or Bay), between Yerba Buena Island (YBI) and the city of Oakland. 
The western limit of the project area is the east portal of the YBI 
tunnel, located in the city of San Francisco. The eastern limit of the 
project area is located approximately 1,312 ft (400 m) west of the Bay 
Bridge toll plaza, where the new and former spans connect with land at 
the Oakland Touchdown in the city of Oakland.

Detailed Description of CALTRANS East Span Removal Project

1. Vibratory and Impact Driving of Temporary Piles
    CALTRANS anticipates temporary access trestles, in-water falsework, 
and cofferdams may be required to dismantle the existing bridge. 
Temporary access trestles, supported by temporary marine piles, and 
cofferdams may be needed to provide construction access. Temporary 
falsework supports will be necessary to provide stability for the 
portions of the structure not yet removed. Marine pile-supported 
falsework is anticipated to be necessary to facilitate removal of the 
superstructure. These temporary structures will be contractor-designed; 
therefore, their exact nature (e.g., size, type, number of piles), 
location, and timing of installation are not known at this point. As 
discussed in detail in the April 13, 2013 IHA application (79 FR 2421; 
January 14, 2014), a maximum of 2,540 temporary piles may be installed 
to support all temporary structures required for bridge dismantling.
    CALTRANS estimates that a maximum of 200 temporary piles may be 
installed during the 1-year period of IHA coverage. Types of temporary 
piles to be installed may include sheet piles, 14-in (0.34-m) H-piles, 
and steel pipe piles, equal to or less than 36-in (0.91-m) in diameter. 
A maximum of 132 days of pile driving may be required to install and/or 
remove piles during the 1-year period of IHA coverage.
    All H-piles would be installed with an impact hammer, without the 
use of a marine pile driving energy attenuator. Impact driving (with 
the exception of pile proofing) will be restricted to June 1 through 
November 30, to avoid the peak migration period for salmonids and 
spawning adult green sturgeon. Vibratory driving and proofing of piles 
may be performed year-round.

[[Page 48747]]

    All pipe piles will be installed with a vibratory hammer. The 
vibratory hammer will be used to drive the majority of the total pile 
lengths. The remaining piles may be impact-driven with the use of a 
marine pile-driving energy attenuator (i.e., air bubble curtain 
system), or other equally effective sound attenuation method (e.g., 
dewatered cofferdam). A maximum of 20 piles may be impact-driven per 
day.
    In the event a pipe pile is installed entirely with a vibratory 
hammer, it still will be subject to final ``proofing'' with an impact 
hammer. ``Proofing'' will be accomplished by using a limited number of 
blows with an impact hammer, intended to test integrity and seating of 
the pile. A maximum of 10% of the piles installed completely with a 
vibratory hammer may be proofed with an impact hammer, without the use 
of a marine pile-driving energy attenuator. Proofing of piles will be 
limited to a maximum of two piles per day, for less than 1 minute per 
pile, administering a maximum of 20 blows per pile.
    In addition to the temporary pipe piles and H-piles described 
above, sheet piles may be driven with a vibratory hammer to construct 
temporary cofferdams or other types of barriers. A cofferdam is a 
temporary enclosure, built within a body of water, usually composed of 
sheet piles welded together. The enclosures generally are watertight, 
allowing them to be fully or partially dewatered for construction 
access in the marine environment. Partially or un-dewatered cofferdams 
also may be used to isolate work areas; preventing water temporarily 
affected by construction activities from mixing with the surrounding 
waters of the Bay.
    When no longer needed, all temporary piles will be retrieved or cut 
off 1.5 ft (0.46 m) below the mudline, in compliance with United States 
Coast Guard requirements. A vibratory pile extractor will be used to 
retrieve piles.
2. Removal of Piers E4 and E5
    CALTRANS proposes the removal of Piers E4 and E5 of the original 
East Span by use of controlled charges to implode each pier into its 
open cellular chambers below the mudline. A Blast Attenuation System 
(BAS) will be used to minimize potential impacts on biological 
resources in the Bay. Both NMFS and CALTRANS believe that the results 
from the Pier E3 Demonstration Project support the use of controlled 
charges as a more expedient method of removal that will cause less 
environmental impact as compared to approved mechanical methods using a 
dry (fully dewatered) cofferdam. Piers E4 and E5 of the original East 
Span are located between the OTD area and YBI, and just south of the 
SFOBB new East Span. These piers are concrete cellular structures that 
occupy areas deep below the mudline, within the water column, and above 
the water line of the Bay.
    The use of controlled charges would greatly reduce in-water work 
periods and shorten the overall duration of marine foundation removal 
compared with mechanical removal. Because of the similar structures for 
both Piers E4 and E5, each would be removed following the same five 
steps:
     Dismantling the fender system and removing the pier cap 
and concrete pedestals;
     Drilling bore holes into the marine foundation;
     Installing and testing the BAS;
     Installing charges, activating the BAS, and imploding the 
pier; and
     Managing and removing remaining dismantling debris.
    Details of these steps are provided below.

2.1 Dismantling of Pier E4 and Pier E5 Fender Systems and Concrete Caps

    Dismantling of the Piers E4 and E5 fender systems and pier caps is 
expected to start in June 2016. The fender systems include timber, 
metal framing, and concrete aprons, which will be removed and disposed 
offsite. The steel piles that support the fender system will be removed 
and recycled off-site. The support piles either will be vibrated out 
and removed whole or will be cut off a minimum of 1.5 ft (0.46 m) below 
the mudline and removed off-site.
    Support barges will be used to move hydraulic excavators equipped 
with hoe rams, shearing attachments, drills, and other equipment, 
including cutting lances and torches that will be used during the 
mechanical dismantling. A barge-mounted crane will be used to move 
equipment onto and off each pier.
    The concrete pedestals and pier cap will be removed by mechanical 
means, using tools including those listed above to break the concrete 
structure into pieces. Support platforms will be installed to provide a 
working surface for the excavators to dismantle the upper portion of 
the piers. All concrete rubble from the mechanical dismantling will be 
placed into exposed cells of the caisson and will fall below the 
mudline for disposal.

2.2 Pier E5 Lower-Chamber Pre-Cast Slab Removal

    The lower caisson cells of Pier E5 on the east and west face of the 
lower segment of the pier are covered with pre-cast concrete slabs. To 
assure that the lower caisson chambers will be open to receive rubble 
during the controlled implosion of Pier E5, these slabs will be removed 
mechanically by breaking them with a modified steel pile that will be 
attached to and controlled by a barge-mounted crane. The controlled 
drop will bring the pile down on each slab. The weight of the modified 
pile will cause each concrete slab to shatter and fall into the caisson 
cells, to be entombed below the mudline.

2.3 Drill Boreholes

    After the mechanical dismantling operations are complete, access 
platforms will be installed on top of each pier to support the drilling 
equipment. The exposed interior cell walls, buttress walls, and outside 
walls will be drilled from the top down, to remove concrete and create 
boreholes to just below the controlled blasting removal limit for each 
pier. Boreholes that are drilled in areas that are inundated with water 
(i.e., to the buttress walls and concrete slabs) will be done using a 
drill bit working within a tubular casing for guidance and to provide 
containment during in-water work. Monitoring will be performed to 
minimize and avoid impacts on water quality during this activity.
    For Pier E5, an overhanging template system will be installed to 
guide the drill below the waterline. For Pier E5, divers will be 
required to cut notches into the buttress walls to guide the drilling 
of underwater boreholes. Pier E4 does not have buttress walls; 
therefore, it will not require in-water notching, and all borehole 
drilling will occur out of the water.

2.4 Blast Attenuation System Installation and Deployment

    The BAS that will be used at Piers E4 and E5 is the same system 
that was successfully used for the Pier E3 Demonstration Project. The 
BAS is a modular system of pipe manifold frames, placed around each 
pier and fed by air compressors to create a curtain of air. The BAS 
will be activated before and during implosion. As shown during the 
Demonstration Project last year (CALTRANS 2016), the BAS will help 
minimize noise and pressure waves generated during each controlled 
blast, to minimize potentially adverse effects on biological resources 
that may be nearby. Each BAS frame is approximately 50.5 ft (15.4 m) 
long by 6 ft (1.8 m) wide. The BAS to be used at Piers E4 and E5 will 
be same system that was used at Pier E3 and will meet the same 
specifications.
    The complete BAS will be installed and tested during the weeks 
leading up

[[Page 48748]]

to each controlled blast. Before installing the BAS, CALTRANS will move 
any existing debris on the Bay floor that may interrupt proper 
installation of the BAS. Existing debris identified as a risk to proper 
installation of the BAS will be moved outside the path of the BAS 
layout. Each BAS frame will be lowered to the bottom of the Bay by a 
barge-mounted crane and positioned into place. Divers will be used to 
assist frame placement, and to connect air hoses to the frames. Frames 
will be situated to contiguously surround the pier. Each frame will be 
weighted to negative buoyancy for activation. Compressors will provide 
enough pressure to achieve a minimal air volume fraction of 3 to 4 
percent, consistent with the successful use of BAS systems in past 
controlled blasting activities, including Pier E3 (CALTRANS 2016). 
System performance is anticipated to provide approximately 80% sound 
and pressure attenuation, based on the results from the Demonstration 
Project (CALTRANS 2016).

2.5 Test Blasts

    Before each pier implosion, test blasts may be conducted within the 
completely installed and operating BAS so that the hydroacoustic 
monitoring equipment will be properly triggered and functional before 
each pier implosion event. A key requirement of the implosion involves 
accurately capturing hydroacoustic information from the controlled 
blast. To accomplish this, a smaller test charge will be used to 
trigger recording instrumentation. Multiple test blast events may be 
required to verify proper instrument operation and calibrate the 
equipment for the implosion event. These same instruments and others of 
the same type will use high-speed recording devices to capture 
hydroacoustic data at both near-field and far-field monitoring 
locations during the implosion.
    The BAS will be in operation during all tests. Tests will use a 
charge weight of approximately 18 grains (0.0025 pound) or less. The 
test charge will be placed along one of the longer faces of the pier 
and inside the BAS while it is operating. Results from test blasts that 
occurred during the Pier E3 Demonstration Project indicate that these 
test blasts will have minimal impacts on fish and marine mammals 
(CALTRANS 2016).

2.6 Acoustic Deterrent Devices

    Prior to controlled implosion of Pier E4 and E5 CALTRANS will 
deploy acoustic deterrent devices (ADD) to deter marine mammals from 
entering exclusion zones. Up to 20 ADDs will be attached to the buoys 
delineating the pinniped exclusion zone, and to monitoring boats or 
other bridge piers near Piers E4 or E5.
    ADDs are commonly used in commercial fishing and at fish farms to 
scare marine mammals away from nets or structures (Gordon et al., 2007; 
Brandt et al. 2013; Gotz and Janik 2013; Schakner and Blumstein 2013) 
and were used for the first time during the Pier E3 implosion to deter 
marine mammals from entering the exclusion zones. The pulse of ADDs 
used during the Pier E3 implosion had a frequency of 10 kHz, a source 
sound level of 132 dB re 1 [mu]Pa, with regular or random interpulse 
intervals of 4 seconds (Airmar Porpoise ADD, Milford, NH). Insufficient 
data exists to determine the effectiveness of the ADDs during the Pier 
E3 implosion. NMFS does not consider the ADDs would have take of marine 
mammals due to their low source level.

2.7 Controlled Implosion of Piers E4 and E5

    Before pier removal via controlled blasting, the bore holes in the 
pier will be loaded with controlled charges. Individual cartridge 
charges, using electronic blasting caps versus pumpable liquid blasting 
agents, have been selected to provide greater control and accuracy in 
determining the individual and total charge weights. Use of individual 
cartridges will allow a refined blast plan that efficiently breaks 
concrete while minimizing the amount of charges needed.
    Boreholes will vary in diameter and depth, and have been designed 
to provide optimal efficiency in transferring the energy created by the 
controlled charges to dismantle the pier. Individual charge weights 
will vary from 20 to 35 lbs (9 to 16 kg), and the total charge weight 
for each controlled blast event will be approximately 11,000 to 12,000 
lbs (5,000 to 5,500 kg). Charges are arranged in different levels 
(decks) and will be separated in the boreholes by stemming. Stemming is 
the insertion of inert materials (e.g., sand or gravel) to insulate and 
retain charges in an enclosed space. Stemming will allow more efficient 
transfer of energy into the structural concrete for fracture, and 
further reduce the release of potential energy into the surrounding 
water column. The blast events for Piers E4 and E5 will each consist of 
approximately 400 individual delays of varying charge weight. The 
entire detonation sequence, consisting of approximately 400 
detonations, will last approximately 3 to 4 seconds for each pier; with 
a minimum delay time of 9 milliseconds (msec) between detonations.

2.8 Debris Removal and Site Restoration

    Following the controlled implosion event and confirmation that the 
area is safe to work in, construction crews will begin to remove all 
associated equipment, including barges, compressors, the BAS, and blast 
mats. CALTRANS expects that a small portion of rubble from each pier 
will fall outside its respective footprint and/or mound within the 
footprint of each pier, and will need to be managed after each 
controlled implosion. Concrete rubble resulting from the controlled 
implosions of Piers E4 and E5 that does not fall into the hollow 
caisson cells will be placed in the remaining caisson cells to be 
entombed below the mudline. The portions of each pier that do not break 
apart during controlled blasting and remain above the removal limits 
will be demolished by mechanical means. This may require the use of 
underwater mechanical equipment, including hydraulic crushing or 
grinding machinery or diver-operated jackhammers.
    Rubble from the controlled implosion that does not fall into the 
hollow caisson cells will be picked up and disposed inside the 
remaining caisson cells, to be entombed below the mudline. Management 
of extraneous rubble will be done by a barge-mounted crane with a clam-
shell bucket. Buckets used during this debris management phase will be 
equipped with a Global Positioning System unit, to accurately guide the 
location of the bucket in the water. The in-water site management 
operation is expected to take a few weeks following each implosion 
event and is anticipated to be completed by the end of December 2016.

Description of Marine Mammals in the Area of the Specified Activity

    Seven species of marine mammals regularly inhabit or rarely or 
seasonally enter the San Francisco Bay (Table 1). The two most common 
species observed are the Pacific harbor seal (Phoca vitulina richardii) 
and the California sea lion (Zalophus californianus). Juvenile northern 
elephant seals (Mirounga angustirostris) seasonally enter the Bay 
(spring and fall), while harbor porpoises (Phocoena phocoena) may enter 
the western side of the Bay throughout the year, but rarely occur near 
the SFOBB east span. Gray whales (Eschrichtius robustus) may enter the 
Bay during their northward migration in the late winter and spring. In 
addition, though rare, northern fur seals (Callorhinus ursinus)

[[Page 48749]]

and bottlenose dolphins (Tursiops truncatus) have also been sighted in 
the Bay. None of these species are listed as endangered or threatened 
under the Endangered Species Act (ESA), or as depleted or a strategic 
stock under the MMPA.

                                        Table 1--Marine Mammal Species Potentially Present in Region of Activity
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            Common name                Scientific name         Status           Occurrence            Seasonality              Range          Abundance
--------------------------------------------------------------------------------------------------------------------------------------------------------
Harbor seal.......................  Phoca vitulina         ..............  Common..............  Year round..........  California..........       30,968
                                     richardii.
California sea lion...............  Zalophus               ..............  Common..............  Year round..........  California..........      296,750
                                     californianus.
Northern fur seal.................  Callorhinus ursinus..  ..............  Rare................  Year round..........  California..........       12,844
Northern elephant seal............  Mirounga               ..............  Occasional..........  Spring & fall.......  California..........      179,000
                                     angustirostris.
Gray whale........................  Eschrichtius robustus  (*)             Rare................  Spring & fall.......  Mexico to the U.S.         20,990
                                                                                                                        Arctic Ocean.
Harbor porpoise...................  Phocoena phocoena....  ..............  Rare................  Year round..........  California..........        9,886
Coastal Bottlenose dolphin........  Tursiops truncatus...  ..............  Rare................  Year round..........  California..........          323
--------------------------------------------------------------------------------------------------------------------------------------------------------
* The E. North Pacific population is not listed under the ESA.

    More detailed information on the marine mammal species found in the 
vicinity of the SFOBB construction site can be found in CALTRANS IHA 
application, and in NMFS stock assessment report (Caretta et al., 
2015), which is available at the following URL: http://www.nmfs.noaa.gov/pr/sars/pdf/pacific_sars_2014_final_noaa_swfsc_tm_549.pdf. Refer to these documents 
for additional information on these species.

Potential Effects of the Specified Activity on Marine Mammals

    This section includes a summary and discussion of the ways that the 
types of stressors associated with the specified activity (e.g., pile 
removal and pile driving) have been observed to impact marine mammals. 
This discussion may also include reactions that we consider to rise to 
the level of a take and those that we do not consider to rise to the 
level of a take (for example, with acoustics, we may include a 
discussion of studies that showed animals not reacting at all to sound 
or exhibiting barely measurable avoidance). This section is intended as 
a background of potential effects and does not consider either the 
specific manner in which this activity will be carried out or the 
mitigation that will be implemented, and how either of those will shape 
the anticipated impacts from this specific activity. The ``Estimated 
Take by Incidental Harassment'' section later in this document will 
include a quantitative analysis of the number of individuals that are 
expected to be taken by this activity. The ``Analysis and Preliminary 
Determinations'' section will include the analysis of how this specific 
activity will impact marine mammals and will consider the content of 
this section, the ``Estimated Take by Incidental Harassment'' section, 
the ``Proposed Mitigation'' section, and the ``Anticipated Effects on 
Marine Mammal Habitat'' section to draw conclusions regarding the 
likely impacts of this activity on the reproductive success or 
survivorship of individuals and from that on the affected marine mammal 
populations or stocks.
    When considering the influence of various kinds of sound on the 
marine environment, it is necessary to understand that different kinds 
of marine life are sensitive to different frequencies of sound. Based 
on available behavioral data, audiograms have been derived using 
auditory evoked potentials, anatomical modeling, and other data, 
Southall et al. (2007) designate ``functional hearing groups'' for 
marine mammals and estimate the lower and upper frequencies of 
functional hearing of the groups. The functional groups and the 
associated frequencies are indicated below (though animals are less 
sensitive to sounds at the outer edge of their functional range and 
most sensitive to sounds of frequencies within a smaller range 
somewhere in the middle of their functional hearing range):
     Low frequency cetaceans (13 species of mysticetes): 
Functional hearing is estimated to occur between approximately 7 Hz and 
25 kHz;
     Mid-frequency cetaceans (32 species of dolphins, seven 
species of larger toothed whales, and 19 species of beaked and 
bottlenose whales): Functional hearing is estimated to occur between 
approximately 150 Hz and 160 kHz;
     High frequency cetaceans (eight species of true porpoises, 
seven species of river dolphins, Kogia, the franciscana, and four 
species of cephalorhynchids): Functional hearing is estimated to occur 
between approximately 200 Hz and 180 kHz;
     Phocid pinnipeds in Water: Functional hearing is estimated 
to occur between approximately 75 Hz and 100 kHz; and
     Otariid pinnipeds in Water: Functional hearing is 
estimated to occur between approximately 100 Hz and 48 kHz.
    As mentioned previously in this document, 7 marine mammal species 
(three cetacean and four pinniped species) are likely to occur in the 
vicinity of the proposed SFOBB pile driving/removal and controlled pier 
detonation area. Of the 2 cetacean species, one belongs to low-
frequency cetacean (gray whale), one mid-frequency cetacean (bottlenose 
dolphin), and one high-frequency cetacean (harbor porpoise). 2 species 
of pinniped are phocid (Pacific harbor seal and northern elephant 
seal), and 2 species of pinniped is otariid (California sea lion and 
northern fur seal). A species' functional hearing group is a 
consideration when we analyze the effects of exposure to sound on 
marine mammals.

Potential Effects From In-Water Pile Driving and Pile Removal

    The proposed CALTRANS SFOBB construction work using in-water pile 
driving and pile removal could adversely affect marine mammal species 
and stocks by exposing them to elevated noise levels in the vicinity of 
the activity area.
    Exposure to high intensity sound for a sufficient duration may 
result in auditory effects such as a noise-induced threshold shift--an 
increase in the auditory threshold after exposure to noise (Finneran et 
al., 2005). Factors that influence the amount of threshold shift 
include the amplitude, duration, frequency content, temporal pattern, 
and energy distribution of noise exposure. The magnitude of hearing 
threshold shift normally decreases over time following cessation of the 
noise exposure. The amount of threshold shift just after exposure is 
the initial threshold shift. If the threshold shift eventually returns 
to zero (i.e., the

[[Page 48750]]

threshold returns to the pre-exposure value), it is a temporary 
threshold shift (Southall et al., 2007).
    Threshold Shift (noise-induced loss of hearing)--When animals 
exhibit reduced hearing sensitivity (i.e., sounds must be louder for an 
animal to detect them) following exposure to an intense sound or sound 
for long duration, it is referred to as a noise-induced threshold shift 
(TS). An animal can experience temporary threshold shift (TTS) or 
permanent threshold shift (PTS). TTS can last from minutes or hours to 
days (i.e., there is complete recovery), can occur in specific 
frequency ranges (i.e., an animal might only have a temporary loss of 
hearing sensitivity between the frequencies of 1 and 10 kHz), and can 
be of varying amounts (for example, an animal's hearing sensitivity 
might be reduced initially by only 6 dB or reduced by 30 dB). PTS is 
permanent, but some recovery is possible. PTS can also occur in a 
specific frequency range and amount as mentioned above for TTS.
    For marine mammals, published data are limited to the captive 
bottlenose dolphin, beluga, harbor porpoise, and Yangtze finless 
porpoise (Finneran et al., 2000, 2002, 2003, 2005, 2007, 2010a, 2010b; 
Finneran and Schlundt, 2010; Lucke et al., 2009; Mooney et al., 2009a, 
2009b; Popov et al., 2011a, 2011b; Kastelein et al., 2012a; Schlundt et 
al., 2000; Nachtigall et al., 2003, 2004). For pinnipeds in water, data 
are limited to measurements of TTS in harbor seals, an elephant seal, 
and California sea lions (Kastak et al., 1999, 2005; Kastelein et al., 
2012b).
    Lucke et al. (2009) found a threshold shift (TS) of a harbor 
porpoise after exposing it to airgun noise with a received sound 
pressure level (SPL) at 200.2 dB (peak-to-peak) re: 1 [mu]Pa, which 
corresponds to a sound exposure level of 164.5 dB re: 1 [mu]Pa\2\ s 
after integrating exposure. NMFS currently uses the root-mean-square 
(rms) of received SPL at 180 dB and 190 dB re: 1 [mu]Pa as the 
threshold above which permanent threshold shift (PTS) could occur for 
cetaceans and pinnipeds, respectively. Because the airgun noise is a 
broadband impulse, one cannot directly determine the equivalent of rms 
SPL from the reported peak-to-peak SPLs. However, applying a 
conservative conversion factor of 16 dB for broadband signals from 
seismic surveys (McCauley, et al., 2000) to correct for the difference 
between peak-to-peak levels reported in Lucke et al. (2009) and rms 
SPLs, the rms SPL for TTS would be approximately 184 dB re: 1 [mu]Pa, 
and the received levels associated with PTS (Level A harassment) would 
be higher. This is still above NMFS' current 180 dB rms re: 1 [mu]Pa 
threshold for injury. However, NMFS recognizes that TTS of harbor 
porpoises is lower than other cetacean species empirically tested 
(Finneran & Schlundt, 2010; Finneran et al., 2002; Kastelein and 
Jennings, 2012).
    Marine mammal hearing plays a critical role in communication with 
conspecifics, and interpretation of environmental cues for purposes 
such as predator avoidance and prey capture. Depending on the degree 
(elevation of threshold in dB), duration (i.e., recovery time), and 
frequency range of TTS, and the context in which it is experienced, TTS 
can have effects on marine mammals ranging from discountable to serious 
(similar to those discussed in auditory masking, below). For example, a 
marine mammal may be able to readily compensate for a brief, relatively 
small amount of TTS in a non-critical frequency range that occurs 
during a time where ambient noise is lower and there are not as many 
competing sounds present. Alternatively, a larger amount and longer 
duration of TTS sustained during time when communication is critical 
for successful mother/calf interactions could have more serious 
impacts. Also, depending on the degree and frequency range, the effects 
of PTS on an animal could range in severity, although it is considered 
generally more serious because it is a permanent condition. Of note, 
reduced hearing sensitivity as a simple function of aging has been 
observed in marine mammals, as well as humans and other taxa (Southall 
et al., 2007), so one can infer that strategies exist for coping with 
this condition to some degree, though likely not without cost.
    In addition, chronic exposure to excessive, though not high-
intensity, noise could cause masking at particular frequencies for 
marine mammals that utilize sound for vital biological functions (Clark 
et al., 2009). Acoustic masking is when other noises such as from human 
sources interfere with animal detection of acoustic signals such as 
communication calls, echolocation sounds, and environmental sounds 
important to marine mammals. Therefore, under certain circumstances, 
marine mammals whose acoustical sensors or environment are being 
severely masked could also be impaired from maximizing their 
performance fitness in survival and reproduction.
    Masking occurs at the frequency band which the animals utilize. 
Therefore, since noise generated from vessels dynamic positioning 
activity is mostly concentrated at low frequency ranges, it may have 
less effect on high frequency echolocation sounds by odontocetes 
(toothed whales). However, lower frequency man-made noises are more 
likely to affect detection of communication calls and other potentially 
important natural sounds such as surf and prey noise. It may also 
affect communication signals when they occur near the noise band and 
thus reduce the communication space of animals (e.g., Clark et al., 
2009) and cause increased stress levels (e.g., Foote et al., 2004; Holt 
et al., 2009).
    Unlike TS, masking, which can occur over large temporal and spatial 
scales, can potentially affect the species at population, community, or 
even ecosystem levels, as well as individual levels. Masking affects 
both senders and receivers of the signals and could have long-term 
chronic effects on marine mammal species and populations. Recent 
science suggests that low frequency ambient sound levels have increased 
by as much as 20 dB (more than 3 times in terms of sound pressure 
level) in the world's ocean from pre-industrial periods, and most of 
these increases are from distant shipping (Hildebrand 2009). For 
CALTRANS proposed SFOBB construction activities, noises from vibratory 
pile driving contribute to the elevated ambient noise levels in the 
project area, thus increasing potential for or severity of masking. 
Baseline ambient noise levels in the Bay are very high due to ongoing 
shipping, construction and other activities in the Bay.
    Finally, exposure of marine mammals to certain sounds could lead to 
behavioral disturbance (Richardson et al., 1995), such as: Changing 
durations of surfacing and dives, number of blows per surfacing, or 
moving direction and/or speed; reduced/increased vocal activities; 
changing/cessation of certain behavioral activities (such as 
socializing or feeding); visible startle response or aggressive 
behavior (such as tail/fluke slapping or jaw clapping); avoidance of 
areas where noise sources are located; and/or flight responses (e.g., 
pinnipeds flushing into water from haulouts or rookeries).
    The onset of behavioral disturbance from anthropogenic noise 
depends on both external factors (characteristics of noise sources and 
their paths) and the receiving animals (hearing, motivation, 
experience, demography) and is also difficult to predict (Southall et 
al., 2007). Currently NMFS uses a received level of 160 dB re 1 [mu]Pa 
(rms) to predict the onset of behavioral harassment from impulse noises 
(such as impact pile driving), and 120 dB re 1 [mu]Pa (rms) for 
continuous noises (such as vibratory pile driving). For the CALTRANS

[[Page 48751]]

SFOBB construction activities, both of these noise levels are 
considered for effects analysis because CALTRANS plans to use both 
impact and vibratory pile driving, as well as vibratory pile removal.
    The biological significance of many of these behavioral 
disturbances is difficult to predict, especially if the detected 
disturbances appear minor. However, the consequences of behavioral 
modification could be biologically significant if the change affects 
growth, survival, and/or reproduction, which depends on the severity, 
duration, and context of the effects.

Potential Effects From Controlled Pier Implosion

    It is expected that an intense impulse from the proposed Piers E4 
and E5 controlled implosion would have the potential to impact marine 
mammals in the vicinity. The majority of impacts would be startle 
behavioral and temporary behavioral modification from marine mammals. 
However, a few individuals of animals could be exposed to sound levels 
that would cause temporal hearing threshold shift (TTS).
    The underwater explosion would send a shock wave and blast noise 
through the water, release gaseous by-products, create an oscillating 
bubble, and cause a plume of water to shoot up from the water surface. 
The shock wave and blast noise are of most concern to marine animals. 
The effects of an underwater explosion on a marine mammal depends on 
many factors, including the size, type, and depth of both the animal 
and the explosive charge; the depth of the water column; and the 
standoff distance between the charge and the animal, as well as the 
sound propagation properties of the environment. Potential impacts can 
range from brief effects (such as behavioral disturbance), tactile 
perception, physical discomfort, slight injury of the internal organs 
and the auditory system, to death of the animal (Yelverton et al., 
1973; DoN, 2001). Non-lethal injury includes slight injury to internal 
organs and the auditory system; however, delayed lethality can be a 
result of individual or cumulative sublethal injuries (DoN, 2001). 
Immediate lethal injury would be a result of massive combined trauma to 
internal organs as a direct result of proximity to the point of 
detonation (DoN, 2001). Generally, the higher the level of impulse and 
pressure level exposure, the more severe the impact to an individual.
    Injuries resulting from a shock wave take place at boundaries 
between tissues of different density. Different velocities are imparted 
to tissues of different densities, and this can lead to their physical 
disruption. Blast effects are greatest at the gas-liquid interface 
(Landsberg 2000). Gas-containing organs, particularly the lungs and 
gastrointestinal tract, are especially susceptible (Goertner 1982; Hill 
1978; Yelverton et al., 1973). In addition, gas-containing organs 
including the nasal sacs, larynx, pharynx, trachea, and lungs may be 
damaged by compression/expansion caused by the oscillations of the 
blast gas bubble. Intestinal walls can bruise or rupture, with 
subsequent hemorrhage and escape of gut contents into the body cavity. 
Less severe gastrointestinal tract injuries include contusions, 
petechiae (small red or purple spots caused by bleeding in the skin), 
and slight hemorrhaging (Yelverton et al., 1973).
    Because the ears are the most sensitive to pressure, they are the 
organs most sensitive to injury (Ketten 2000). Sound-related damage 
associated with blast noise can be theoretically distinct from injury 
from the shock wave, particularly farther from the explosion. If an 
animal is able to hear a noise, at some level it can damage its hearing 
by causing decreased sensitivity (Ketten 1995). Sound-related trauma 
can be lethal or sublethal. Lethal impacts are those that result in 
immediate death or serious debilitation in or near an intense source 
and are not, technically, pure acoustic trauma (Ketten 1995). Sublethal 
impacts include hearing loss, which is caused by exposures to 
perceptible sounds. Severe damage (from the shock wave) to the ears 
includes tympanic membrane rupture, fracture of the ossicles, damage to 
the cochlea, hemorrhage, and cerebrospinal fluid leakage into the 
middle ear. Moderate injury implies partial hearing loss due to 
tympanic membrane rupture and blood in the middle ear. Permanent 
hearing loss also can occur when the hair cells are damaged by one very 
loud event, as well as by prolonged exposure to a loud noise or chronic 
exposure to noise. The level of impact from blasts depends on both an 
animal's location and, at outer zones, on its sensitivity to the 
residual noise (Ketten, 1995).
    However, the above discussion concerning underwater explosion only 
pertains to open water detonation in a free field. CALTRANS' Pier E4 
and E5 demolition project using controlled implosion uses a confined 
detonation method, meaning that the charges would be placed within the 
structure. Therefore, most energy from the explosive shock wave would 
be absorbed through the destruction of the structure itself, and would 
not propagate through the open water. Measurements and modeling from 
confined underwater detonation for structure removal showed that energy 
from shock waves and noise impulses were greatly reduced in the water 
column (Hempen et al., 2007; CALTRANS 2016). Therefore, with monitoring 
and mitigation measures discussed above, CALTRANS Pier E4 and E5 
controlled implosions are not likely to have the injury or mortality 
effects on marine mammals in the project vicinity. Instead, NMFS 
considers that CALTRANS' proposed Pier E4 and E5 controlled implosions 
in the San Francisco Bay are most like to cause Level B behavioral 
harassment and maybe TTS in a few individuals of marine mammals, as 
discussed below.
    Changes in marine mammal behavior are expected to result from an 
acute stress response. This expectation is based on the idea that some 
sort of physiological trigger must exist to change any behavior that is 
already being performed. The exception to this rule is the case of 
auditory masking, which is not likely since the CALTRANS' controlled 
implosion is only two short, sequential detonations that last for 
approximately 3-4 seconds.

Potential Effects on Marine Mammal Habitat

    The removal of the SFOBB East Span is not likely to negatively 
affect the habitat of marine mammal populations because no permanent 
loss of habitat will occur, and only a minor, temporary modification of 
habitat will occur. The original SFOBB area is not used as a haul-out 
site by pinnipeds or as a major foraging area. Therefore, demolition of 
the concrete marine foundations and pile installation and removal 
activities are unlikely to permanently decrease fish populations in the 
area and are unlikely to affect marine mammal populations.
    Project activities will not affect any pinniped haul-out sites or 
pupping sites. The YBI harbor seal haul-out site is on the opposite 
site of the island from the SFOBB Project area. Because of the distance 
and the island blocking the sound, underwater noise and pressure levels 
from the SFOBB Project will not reach the haul-out. Other haul-out 
sites for sea lions and harbor seals are at a sufficient distance from 
the SFOBB Project area that they will not be affected. The closest 
recognized harbor seal pupping site is at Castro Rocks, approximately 
8.7 mi (14 km) from the SFOBB Project area. No sea lion rookeries are 
found in the Bay.
    The addition of underwater sound from SFOBB Project activities to

[[Page 48752]]

background noise levels can constitute a potential cumulative impact on 
marine mammals. However, these potential cumulative noise impacts will 
be short in duration.
    SPLs from impact pile driving and pier implosion have the potential 
to injure or kill fish in the immediate area. During previous pier 
implosion and pile driving activities, CALTRANS has reported mortality 
to marine mammals' prey species, including northern anchovies and 
Pacific herring (CALTRANS 2016). These few isolated fish mortality 
events are not anticipated to have a substantial effect on prey species 
population or their availability as a food resource for marine mammals.
    Studies also suggest that larger fish are generally less 
susceptible to death or injury than small fish. Moreover, elongated 
forms that are round in cross section are less at risk than deep-bodied 
forms. Orientation of fish relative to the shock wave may also affect 
the extent of injury. Open water pelagic fish (e.g., mackerel) seem to 
be less affected than reef fishes. The results of most studies are 
dependent upon specific biological, environmental, explosive, and data 
recording factors.
    The huge variation in fish populations, including numbers, species, 
sizes, and orientation and range from the detonation point, makes it 
very difficult to accurately predict mortalities at any specific site 
of detonation. Most fish species experience a large number of natural 
mortalities, especially during early life-stages, and any small level 
of mortality caused by the CALTRANS' two controlled implosions will 
likely be insignificant to the population as a whole.

Proposed Mitigation Measures

    In order to issue an incidental take authorization 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 adverse 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.

1. Proposed Mitigation Measures for In-water Pile Driving and Pile 
Removal

    For the proposed CALTRANS SFOBB construction activities, CALTRANS 
worked with NMFS and proposed the following mitigation measures to 
minimize the potential impacts to marine mammals in the project 
vicinity. The primary purpose of these mitigation measures is to detect 
marine mammals within or about to enter designated exclusion zones 
corresponding to NMFS current injury thresholds and to initiate 
immediate shutdown or power down of the piling hammer, making it very 
unlikely potential injury or TTS to marine mammals would occur, and to 
reduce the intensity of Level B behavioral harassment.

Use of Noise Attenuation Devices

    To reduce impact on marine mammals, CALTRANS shall use a marine 
pile driving energy attenuator (i.e., air bubble curtain system), or 
other equally effective sound attenuation method (e.g., dewatered 
cofferdam) for all impact pile driving, with the exception of pile 
proofing and H-piles.

Establishment of Exclusion and Level B Harassment Zones

    Before the commencement of in-water construction activities, which 
include impact pile driving and vibratory pile driving, CALTRANS shall 
establish ``exclusion zones'' where received underwater sound pressure 
levels (SPLs) are higher than 180 dB (rms) and 190 dB (rms) re 1 [mu]Pa 
for cetaceans and pinnipeds, respectively, and ``Level B behavioral 
harassment zones'' where received underwater sound pressure levels 
(SPLs) are higher than 160 dB (rms) and 120 dB (rms) re 1 [mu]Pa for 
impulse noise sources (impact pile driving) and non-impulses noise 
sources (vibratory pile driving), respectively. Before the sizes of 
actual zones are determined based on hydroacoustic measurements, 
CALTRANS shall establish these zones based on prior measurements 
conducted during SFOBB constructions, as described in Table 2 of this 
document.

                              Table 2--Temporary Exclusion and Level B Harassment Zones for Various Pile Driving Activities
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                               Distance to 120    Distance to 160    Distance to 180    Distance to 190
     Pile driving/dismantling activities              Pile size  (m)            dB re 1 [mu]Pa     dB re 1 [mu]Pa     dB re 1 [mu]Pa     dB re 1 [mu]Pa
                                                                                  (rms) (m)          (rms) (m)          (rms) (m)          (rms) (m)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Vibratory Driving...........................  24                                          2,000                 NA                 NA                 NA
                                              36                                          2,000                 NA                 NA                 NA
                                              Sheet pile                                  2,000                 NA                 NA                 NA
Attenuated Impact Driving...................  24                                             NA              1,000                235                 95
                                              36                                             NA              1,000                235                 95
Unattenuated Proofing.......................  24                                             NA              1,000                235                 95
                                              36                                             NA              1,000                235                 95
Unattenuated Impact Driving.................  H-pile                                         NA              1,000                235                 95
--------------------------------------------------------------------------------------------------------------------------------------------------------

    Once the underwater acoustic measurements are conducted during 
initial test pile driving, CALTRANS shall adjust the size of the 
exclusion zones and Level B behavioral harassment zones, and monitor 
these zones accordingly.
    NMFS-approved protected species observers (PSOs) shall conduct 
initial survey of the exclusion zones to ensure that no marine mammals 
are seen within the zones before impact pile driving of a pile segment 
begins. If marine mammals are found within the exclusion zone, impact 
pile driving of the segment would be delayed until they move out of the 
area. If a marine mammal is seen above water and then dives below, the 
contractor would wait 15 minutes for pinnipeds and small cetaceans 
(harbor porpoise), and harbor porpoise and 30 minutes for bottlenose 
dolphins and gray whales. If no marine mammals are seen by the observer 
in that time it can be assumed that the animal has moved beyond the 
exclusion zone. This 15-minute criterion is based on scientific 
evidence that harbor seals in San Francisco Bay dive for a mean time of 
0.50 minutes to 3.33 minutes (Harvey and Torok, 1994), and the mean 
diving duration for harbor porpoises ranges from 44 to 103 seconds 
(Westgate et al., 1995).
    If pile driving of a segment ceases for 30 minutes or more and a 
marine mammal is sighted within the designated exclusion zone prior to 
commencement of pile driving, the observer(s) must notify the Resident 
Engineer (or other authorized individual) immediately and continue

[[Page 48753]]

to monitor the exclusion zone. Operations may not resume until the 
marine mammal has exited the exclusion zone.

Soft Start

    In order to provide additional protection to marine mammals near 
the project area by allowing marine mammals to vacate the area prior to 
receiving a higher noise exposure, CALTRANS and its contractor will 
also ``soft start'' the hammer prior to operating at full capacity. 
This should expose fewer animals to loud sounds both underwater and 
above water. This would also ensure that, although not expected, any 
pinnipeds and cetaceans that are missed during the initial exclusion 
zone monitoring will not be injured.

Shut-Down Measure

    CALTRANS shall implement shutdown measures if a marine mammal is 
sighted approaching the Level A exclusion zone. In-water construction 
activities shall be suspended until the marine mammal is sighted moving 
away from the exclusion zone, or if a pinniped or harbor porpoise is 
not sighted for 15 minutes after the shutdown, or if a bottlenose 
dolphin or gray whale is not sighted for 30 minutes after the shutdown.

2. Proposed Mitigation Measures for Confined Implosion

    For CALTRANS's proposed Piers E4 and E5 controlled implosion, 
CALTRANS worked with NMFS and proposed the following mitigation 
measures to minimize the potential impacts to marine mammals in the 
project vicinity. The primary purposes of these mitigation measures are 
to minimize sound levels from the activities, to monitor marine mammals 
within designated exclusion zones and zones of influence (ZOI). 
Specific proposed mitigation measures are described below.

Time Restriction

    Implosion of Piers E4 and E5 would only be conducted during 
daylight hours and with enough time for pre and post implosion 
monitoring, and with good visibility when the largest exclusion zone 
can be visually monitored.

Installation of Blast Attenuation System (BAS)

    Prior to the Piers E4 and E5 demolition, CALTRANS should install a 
Blast Attenuation System (BAS) as described above to reduce the 
shockwave from the implosion.

Establishment of Level A Exclusion Zone

    Due to the different hearing sensitivities among different taxa of 
marine mammals, NMFS has established a series of take thresholds from 
underwater explosions for marine mammals belonging to different 
functional hearing groups (Table 3). Under these criteria, marine 
mammals from different taxa will have different impact zones (exclusion 
zones and zones of influence).
    CALTRANS will establish an exclusion zone for both the mortality 
and Level A harassment zone (permanent hearing threshold shift or PTS, 
GI track injury, and slight lung injury) using the largest radius 
estimated harbor and northern elephant seals. CALTRANS will use 
measured distances to marine mammal threshold distances from the 
implosion of Pier E3 as predicted distances to the thresholds for the 
implosions of Piers E4 and E5 (Table 4). The use of measured peak 
pressure, cumulative SEL, and impulse levels from the Pier E3 implosion 
provide a conservative estimate for the proposed implosions of Piers E4 
and E5. The Piers E4 and E5 caisson structures are smaller than the 
Pier E3 caisson structure and will require fewer explosive charges to 
implode. The maximum charge weight for the implosions of Piers E4 and 
E5 is 35 pounds/delay, the same as used for the implosion of Pier E3. 
However, the total explosive weight, number of individual detonations, 
and total time of implosion event will be less for these smaller piers.

                                       Table 3--NMFS Take Thresholds for Marine Mammals From Underwater Implosions
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                         Level B harassment               Level A               Serious injury
                                                ------------------------------------    harassment    ----------------------------------
            Group                   Species                                         ------------------     Gastro-                          Mortality
                                                    Behavioral            TTS                             intestinal          Lung
                                                                                            PTS             tract
--------------------------------------------------------------------------------------------------------------------------------------------------------
Mid-freq cetacean............  Bottlenose        167 dB SEL......  172 dB SEL or     187 dB SEL or     237 dB SPL or    39.1M1/3 (1+[D/  91.4M1/3 (1+[D/
                                dolphin.                            224 dB SPLpk.     230 dB SPLpk.     104 psi.         10.081])1/2 Pa-  10.081])1/2 Pa-
                                                                                                                         sec.             sec.
                                                                                                                        where: M = mass  where: M = mass
                                                                                                                         of the animals   of the animals
                                                                                                                         in kg.           in kg.
                                                                                                                        D = depth of     D = depth of
                                                                                                                         animal in m.     animal in m.
High-freq cetacean...........  Harbor porpoise.  141 dB SEL......  146 dB SEL or     161 dB SEL or
                                                                    195 dB SPLpk.     201 dB SPLpk.
Phocidae.....................  Harbor seal &     172 dB SEL......  177 dB SEL or     192 dB SEL or
                                northern                            212 dB SPLpk.     218 dB SPLpk.
                                elephant seal.
Otariidae....................  California sea    195 dB SEL......  200 dB SEL or     215 dB SEL or
                                lion & northern                     212 dBpk.         218 dB SPLpk.
                                fur seal.
--------------------------------------------------------------------------------------------------------------------------------------------------------
* Note: All dB values are referenced to 1 [mu]Pa. SPLpk = Peak sound pressure level; psi = pounds per square inch.


                          Table 4--Measured Distances to Underwater Blasting Threshold Criteria for Levels A and B Harassment and Mortality From the Pier E3 Implosion
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                      Level B criteria                                                   Level A criteria
             Species             ---------------------------------------------------------------------------------------------------------------------------------------        Mortality
                                      Behavioral response          TTS Dual criteria *         PTS Dual criteria *     Gastro-intestinal track        Lung injury
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Harbor Seal.....................  2,460 ft (750 m)...........  1,658 ft (505 m)..........  507 ft (155 m)............  <100 ft (30 m).........  <100 ft (30 m).........  <100 ft (30 m).
                                                               104 ft (32 m).............  65 ft (20 m)..............
California Sea Lion.............  387 ft (118 m).............  261 ft (80 m).............  80 ft (24 m)..............  <100 ft (30 m).........  <100 ft (30 m).........  <100 ft (30 m).
                                                               104 ft (32 m).............  65 ft (20 m)..............

[[Page 48754]]

 
Northern Elephant Seal..........  2,460 ft (750 m)...........  1,658 ft (505 m)..........  507 ft (155 m)............  <100 ft (30 m).........  <100 ft (30 m).........  <100 ft (30 m).
                                                               104 ft (32 m).............  65 ft (20 m)..............
Northern fur seal...............  387 ft (118 m).............  261 ft (80 m).............  80 ft (24 m)..............  <100 ft (30 m).........  <100 ft (30 m).........  <100 ft (30 m).
                                                               104 ft (32 m).............  65 ft (20 m)..............
Harbor Porpoise.................  8,171 ft (2,491 m).........  5,580 ft 1,701 m).........  1,777 ft (542 m)..........  <100 ft (30 m).........  <100 ft (30 m).........  <100 ft (30 m).
                                                               400 ft (122 m)............  249 ft (76 m).............
Bottlenose Dolphin..............  1,255 ft (383 m)...........  855 ft (261 m)............  271 ft (83 m).............  <100 ft (30 m).........  <100 ft (30 m).........  <100 ft (30 m).
                                                               202 ft (62 m).............  112 ft (34 m).............
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Note:
* For the TTS and PTS criteria thresholds with dual criteria, the largest criteria distances (i.e., more conservative) are shown in bold.

Establishment of Level B Temporary Hearing Threshold Shift (TTS) Zone 
of Influence

    As shown in Table 3, for harbor and northern elephant seals, this 
will cover the area out to 212 dB peak SPL or 177 dB SEL, whichever 
extends out the furthest. Hydroacoustic modeling indicates this 
isopleth would extend out to 1,658 ft (505 m) from the pier. For harbor 
porpoises, this will cover the area out to 195 dB peak SPL or 146 dB 
SEL, whichever extends out the furthest, to 5,580 ft (1,701 m) from the 
pier. As discussed previously, the presence of harbor porpoises in this 
area is unlikely but monitoring will be employed to confirm their 
absence. For California sea lions, the distance to the Level B TTS zone 
of influence will cover the area out to 212 dB peak SPL or 200 dB SEL. 
This distance was calculated at 261 ft (80 m) from Pier E3, well within 
the exclusion zone previously described. Hearing group specific Level B 
TTS zone of influence ranges are provided in Table 4.

Establishment of Level B Behavioral Zone of Influence

    As shown in Table 3, for harbor seals and northern elephant seals, 
this will cover the area out to 172 dB SEL. Hydroacoustic measurement 
indicates this isopleth would extend out to 2,460 ft (750 m) from the 
pier. For harbor porpoises, this will cover the area out to 141 dB SEL. 
Hydroacoustic measurement indicates this isopleth would extend out to 
8,171 ft (2,941 m) from the pier. As discussed previously, the presence 
of harbor porpoises in this area is unlikely but monitoring will be 
employed to confirm their absence. For California sea lions, the 
distance to the Level B behavioral harassment ZOI will cover the area 
out to 195 dB SEL. This distance was calculated at 387 ft (118 m) from 
the pier, well within the exclusion zone previously described. Hearing 
group specific Level B TTS zone of influence ranges are provided in 
Table 4.

Communication

    All PSOs will be equipped with mobile phones and a VHF radio as a 
backup. One person will be designated as the Lead PSO and will be in 
constant contact with the Resident Engineer on site and the blasting 
crew. The Lead PSO will coordinate marine mammal sightings with the 
other PSOs. PSOs will contact the other PSOs when a sighting is made 
within the exclusion zone or near the exclusion zone so that the PSOs 
within overlapping areas of responsibility can continue to track the 
animal and the Lead PSO is aware of the animal. If it is within 30 
minutes of blasting and an animal has entered the exclusion zone or is 
near it, the Lead PSO will notify the Resident Engineer and blasting 
crew. The Lead PSO will keep them informed of the disposition of the 
animal.

Mitigation Conclusions

    NMFS has carefully evaluated the applicant's proposed mitigation 
measures and considered a range of other measures in the context of 
ensuring that NMFS prescribes the means of effecting 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:
     The manner in which, and the degree to which, the 
successful implementation of the measure is expected to minimize 
adverse impacts to marine mammals.
     The proven or likely efficacy of the specific measure to 
minimize adverse impacts as planned.
     The practicability of the measure for applicant 
implementation.
    Any mitigation measure(s) prescribed by NMFS 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 numbers of marine mammals (total number or 
number at biologically important time or location) exposed to received 
levels of pile driving and pile removal or other activities expected to 
result in the take of marine mammals (this goal may contribute to 1, 
above, or to reducing harassment takes only).
    (3) A reduction in the number of times (total number or number at 
biologically important time or location) individuals would be exposed 
to received levels of pile driving and pile removal, or other 
activities expected to result in the take of marine mammals (this goal 
may contribute to 1, above, or to reducing harassment takes only).
    (4) A reduction in the intensity of exposures (either total number 
or number at biologically important time or location) to received 
levels of pile driving, or other activities expected to result in the 
take of marine mammals (this goal may contribute to a, above, or to 
reducing the severity of harassment takes only).
    (5) Avoidance or minimization of adverse effects to marine mammal 
habitat, paying special attention to the food base, activities that 
block or limit passage to or from biologically important areas, 
permanent destruction of habitat, or temporary destruction/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 applicant's proposed measures, as 
well as other measures considered by NMFS,

[[Page 48755]]

NMFS has preliminarily determined that the proposed mitigation measures 
provide the means of effecting the least practicable impact on marine 
mammals 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 incidental take authorization (ITA) 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 ITAs 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. CALTRANS has proposed marine 
mammal monitoring measures as part of the IHA application. It can be 
found at http://www.nmfs.noaa.gov/pr/permits/incidental.htm. The plan 
may be modified or supplemented based on comments or new information 
received from the public during the public comment period.
    Monitoring measures prescribed by NMFS should accomplish one or 
more of the following general goals:
    (1) An increase in the probability of detecting marine mammals, 
both within the mitigation zone (thus allowing for more effective 
implementation of the mitigation) and in general to generate more data 
to contribute to the analyses mentioned below;
    (2) An increase in our understanding of how many marine mammals are 
likely to be exposed to levels of pile driving that we associate with 
specific adverse effects, such as behavioral harassment, TTS, or PTS;
    (3) An increase in our understanding of how marine mammals respond 
to stimuli expected to result in take and how anticipated adverse 
effects on individuals (in different ways and to varying degrees) may 
impact the population, species, or stock (specifically through effects 
on annual rates of recruitment or survival) through any of the 
following methods:
    [ssquf] Behavioral observations in the presence of stimuli compared 
to observations in the absence of stimuli (need to be able to 
accurately predict received level, distance from source, and other 
pertinent information);
    [ssquf] Physiological measurements in the presence of stimuli 
compared to observations in the absence of stimuli (need to be able to 
accurately predict received level, distance from source, and other 
pertinent information);
    [ssquf] Distribution and/or abundance comparisons in times or areas 
with concentrated stimuli versus times or areas without stimuli;
    (4) An increased knowledge of the affected species; and
    (5) An increase in our understanding of the effectiveness of 
certain mitigation and monitoring measures.

Proposed Monitoring Measures

1. Monitoring for Pile Driving and Pile Removal

(1) Visual Monitoring
    Besides using monitoring for implementing mitigation (ensuring 
exclusion zones are clear of marine mammals before pile driving begins 
and after shutdown measures), marine mammal monitoring will also be 
conducted to assess potential impacts from CALTRANS construction 
activities. CALTRANS will implement onsite marine mammal monitoring for 
100% of all unattenuated impact pile driving of H-piles for 180- and 
190-dB re 1 [mu]Pa exclusion zones and 160-dB re 1 [mu]Pa Level B 
harassment zone and attenuated impact pile driving (except pile 
proofing) for 180- and 190-dB re 1 [mu]Pa exclusion zones. CALTRANS 
will also monitor 20% of the attenuated impact pile driving for the 
160-dB re 1 [mu]Pa Level B harassment zone, and 20% of vibratory pile 
driving for the 120-dB re 1 [mu]Pa Level B harassment zone.
(2) Protected Species Observers (PSOs)
    Monitoring of the pinniped and cetacean exclusion zones shall be 
conducted by a minimum of three qualified NMFS-approved PSOs. 
Observations will be made using high-quality binoculars (e.g., Zeiss, 
10 x 42 power). PSOs will be equipped with radios or cell phones for 
maintaining contact with other observers and CALTRANS engineers, and 
range finders to determine distance to marine mammals, boats, buoys, 
and construction equipment.
(3) Data Collection
    Data on all observations will be recorded and will include the 
following information:
     Location of sighting;
     Species;
     Number of individuals;
     Number of calves present;
     Duration of sighting;
     Behavior of marine animals sighted;
     Direction of travel; and
     When in relation to construction activities did the 
sighting occur (e.g., before, ``soft-start'', during, or after the pile 
driving or removal).

1. Monitoring for Confined Implosion of Piers E4 and E5

    Monitoring for implosion impacts to marine mammals will be based on 
the SFOBB pile driving monitoring protocol. Pile driving has been 
conducted for the SFOBB construction project since 2000 with 
development of several NMFS-approved marine mammal monitoring plans 
(CALTRANS 2004; 2013). Most elements of these marine mammal monitoring 
plans are similar to what would be required for underwater implosions. 
These monitoring plans would include monitoring an exclusion zone and 
ZOIs for TTS and behavioral harassment described above.
(1) Protected Species Observers (PSOs)
    A minimum of 8-10 PSOs would be required during the Piers E4 and E5 
controlled implosion so that the exclusion zone, Level B Harassment TTS 
and Behavioral ZOIs, and surrounding area can be monitored. One PSO 
would be designated as the Lead PSO and would receive updates from 
other PSOs on the presence or absence of marine mammals within the 
exclusion zone and would notify the Environmental Compliance Manager of 
a cleared exclusion zone to the implosion.
(2) Monitoring Protocol
    Implosions of Piers E4 and E5 will be conducted only during 
daylight hours and with enough time for pre and post-implosion 
monitoring, and with good weather (i.e., clear skies and no high 
winds). This work will be completed so that PSOs will be able to detect 
marine mammals within the exclusion zones and beyond. The Lead PSO will 
be in contact with other PSOs. If any marine mammals enter an exclusion 
zone within 30 minutes of blasting, the Lead PSO will notify the 
Environmental Compliance Manager that the implosion may need to be 
delayed. The Lead PSO will keep the Environmental Compliance Manager 
informed about the disposition of the animal. If the animal remains in 
the exclusion zone, blasting will be delayed until it has left the 
exclusion zone. If the animal dives and is not seen again, blasting 
will be delayed at least 15 minutes for pinnipeds and small cetacean 
(harbor porpoise), and 30 minutes for bottlenose dolphin. After the 
implosion has occurred, the PSOs will continue to monitor the area for 
at least 60 minutes.

[[Page 48756]]

(3) Data Collection
    Each PSO will record the observation position, start and end times 
of observations, and weather conditions (i.e., sunny/cloudy, wind 
speed, fog, visibility). For each marine mammal sighting, the following 
will be recorded, if possible:
     Species.
     Number of animals (with or without pup/calf).
     Age class (pup/calf, juvenile, adult).
     Identifying marks or color (e.g., scars, red pelage, 
damaged dorsal fin).
     Position relative to Piers E4 or E5 (distance and 
direction).
     Movement (direction and relative speed).
     Behavior (e.g., logging [resting at the surface], 
swimming, spy-hopping [raising above the water surface to view the 
area], foraging).
(4) Post-Implosion Survey
    Although any injury or mortality from the implosions of Piers E4 
and E5 is very unlikely, boat or shore surveys will be conducted for 3 
days following the event, to determine whether any injured or stranded 
marine mammals are in the area. If an injured or dead animal is 
discovered during these surveys or by other means, the NMFS-designated 
stranding team will be contacted to pick up the animal. Veterinarians 
will treat the animal or will conduct a necropsy to attempt to 
determine whether it stranded because of the Piers E4 and E5 
implosions.

Proposed Reporting Measures

    CALTRANS would be required to submit a draft monitoring report 
within 90 days after completion of the construction work or the 
expiration of the IHA (if issued), whichever comes earlier. This draft 
report would detail the monitoring protocol, summarize the data 
recorded during monitoring, and estimate the number of marine mammals 
that may have been harassed. NMFS would have an opportunity to provide 
comments on the draft report within 30 days, and if NMFS has comments, 
CALTRANS would address the comments and submit a final report to NMFS 
within 30 days. If no comments are provided by NMFS after 30 days 
receiving the report, the draft report is considered to be final.

Marine Mammal Stranding Plan

    A stranding plan for the Pier E3 implosion was prepared in 
cooperation with the local NMFS-designated marine mammal stranding, 
rescue, and rehabilitation center. An updated version of this plan will 
be implemented during implosions of Piers E4 and E5. Although avoidance 
and minimization measures likely will prevent any injuries, 
preparations will be made in the unlikely event that marine mammals are 
injured. Elements of the plan will include the following:
    1. The stranding crew will prepare treatment areas at an NMFS-
designated facility for cetaceans or pinnipeds that may be injured from 
the implosions. Preparation will include equipment to treat lung 
injuries, auditory testing equipment, dry and wet caged areas to hold 
animals, and operating rooms if surgical procedures are necessary.
    2. A stranding crew and a veterinarian will be on call near the 
Piers E4 and E5 area at the time of the implosions, to quickly recover 
any injured marine mammals, provide emergency veterinary care, 
stabilize the animal's condition, and transport individuals to an NMFS-
designated facility. If an injured or dead animal is found, NMFS (both 
the regional office and headquarters) will be notified immediately, 
even if the animal appears to be sick or injured from causes other than 
the implosions.
    3. Post-implosion surveys will be conducted immediately after the 
event and over the following 3 days to determine whether any injured or 
dead marine mammals are in the area.
    4. Any veterinarian procedures, euthanasia, rehabilitation 
decisions, and time of release or disposition of the animal will be at 
the discretion of the NMFS-designated facility staff and the 
veterinarians treating the animals. Any necropsies to determine whether 
the injuries or death of an animal was the result of an implosion or 
other anthropogenic or natural causes will be conducted at an NMFS-
designated facility by the stranding crew and veterinarians. The 
results will be communicated to both the CALTRANS and to NMFS as soon 
as possible, followed by a written report within a month.

Estimated Take by Incidental Harassment

    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].
    The distance to marine mammal threshold criteria for pile driving 
and blasting activities, and corresponding zones of influence (ZOI) 
have been determined based on underwater sound and pressure 
measurements collected during pervious activities in the SFOBB Project 
area. The numbers of marine mammals by species that may be taken by 
each type of take were calculated based on distance to the marine 
mammal threshold criteria, duration of the activity, and the estimated 
density of each species in the ZOI.

Estimates of Species Densities of Marine Mammals

    No systematic line transect surveys of marine mammals have been 
performed in the San Francisco Bay. Therefore, the in-water densities 
of harbor seals, California sea lions, and harbor porpoises were 
calculated based on 15 years of observations during monitoring for the 
SFOBB construction and demolition. The amount of monitoring performed 
per year varied depending on the frequency and duration of construction 
activities with the potential to affect marine mammals. During the 237 
days of monitoring from 2000 through 2015 (including 15 days of 
baseline monitoring in 2003), 822 harbor seals, 77 California sea 
lions, and 9 harbor porpoises were observed within the waters of the 
SFOBB east span. Density estimates for other species were made from 
stranding data, provided by the Marine Mammal Center (MMC).
1. Pacific Harbor Seal Density Estimates
    Harbor seal density was calculated from all observations of animals 
in water during SFOBB Project monitoring from 2000 to 2015, divided by 
the size of the project area. These observations included data from 
baseline, pre-, during and post-pile driving, mechanical dismantling, 
onshore blasting, and offshore implosion activities. During this time, 
the population of harbor seals in the Bay remained stable (Manugian 
2013). Therefore, substantial differences in numbers or behaviors of 
seals hauling out, foraging, or in their movements are not anticipated. 
All harbor seal observations within a 1 km\2\ area were used in the 
estimate. Distances were recorded using a laser range finder (Bushnell 
Yardage Pro Elite 1500;  1.0 yard accuracy). Care was taken 
to eliminate multiple observations of the same animal, although this 
was difficult when more than three seals were foraging in the same 
area.
    Density of harbor seals was highest near YBI and Treasure Island, 
probably

[[Page 48757]]

because of the haul-out site and nearby foraging areas in Coast Guard 
and Clipper coves. Therefore, density estimates were calculated for a 
higher density area within 4,921 ft (1,500 m) west of Piers E4 and E5, 
which included the two foraging coves. A lower density estimate was 
calculated from the areas east of Piers E4 and E5, and beyond 4,921 ft 
(1,500 m) north and south of the bridge. Harbor seal densities in these 
two areas in spring-summer and fall-winter seasons are provided in 
Table 5.
2. California Sea Lion Density Estimates
    Within the SFOBB Project area, California sea lion density was 
calculated from all observations of animals in water during SFOBB 
Project monitoring from 2000 to 2015, divided by the size of the 
project area. These observations included data from baseline, pre, 
during, and post-pile driving, mechanical dismantling, onshore 
blasting, and offshore implosion activities. All sea lion observations 
within a 1 km\2\ area were used in the estimate. Distances were 
recorded using a laser range finder (Bushnell Yardage Pro Elite 1500; 
 1.0 yard accuracy). Care was taken to eliminate multiple 
observations of the same animal, although most sea lion observations 
involve a single animal.
    California sea lion densities in late spring-early summer and late 
summer-fall seasons are provided in Table 5.
3. Northern Elephant Seal Density Estimates
    Northern elephant seal density in the project area was calculated 
from the stranding records of the MMC, from 2004 to 2014. These data 
included both injured or sick seals and healthy seals. Approximately 
100 elephant seals were reported in the Bay during this time; most of 
these hauled out and likely were sick or starving. The actual number of 
individuals in the Bay may have been higher because not all individuals 
would necessarily have hauled out. Some individuals may have simply 
left the Bay soon after entering. Data from the MMC show several 
elephant seals stranding on Treasure Island, and one healthy elephant 
seal was observed resting on the beach in Clipper Cove in 2012. 
Elephant seal pups or juveniles also may have stranded after weaning in 
the spring and when they returned to California in the fall (September 
through November). Density of northern elephant seal is estimated as 
the number of stranded seals over the SFOBB project area, which is 0.03 
animal/km\2\ (Table 5).
4. Harbor Porpoise Density Estimates
    Harbor porpoise density was calculated from all observations during 
SFOBB Project monitoring, from 2000 to 2015. These observations 
included data from baseline, pre, during and post-pile driving, and 
onshore implosion activities. Over this period, the number of harbor 
porpoises that were observed entering and using the Bay increased. 
During the 15 years of monitoring in the SFOBB Project area, only nine 
harbor porpoises were observed, and all occurred between 2006 and 2015 
(including two in 2014 and five in 2015). Density of harbor porpoise is 
estimated to be 0.021 animal/km\2\ (Table 5).
5. Gray Whale Density Estimate
    Gray whale density was estimated for the entire Bay as no 
observations have occurred of gray whales in the SFOBB Project area. 
Each year, two to six gray whales enter the Bay, presumably to feed, in 
the late winter through spring (February through April), per the MMC. 
Gray whales rarely occur in the Bay from October through December. The 
gray whale density was estimated based on a maximum of 6 whales 
occurring within the main area of San Francisco Bay, which yielded a 
density of 0.00004/km\2\ (Thorson, pers. comm., 2014).

                 Table 5--Estimated In-Water Density of Marine Mammals in the SFOBB Project Area
----------------------------------------------------------------------------------------------------------------
                                                                         Density west of       Density east of
                                                                         piers E4 and E5    piers E4 and E5 and/
                 Species                   Main season of occurrence    within 1,500 m of   or beyond 1,500 m of
                                                                         SFOBB (animals/       SFOBB (animals/
                                                                             km\2\)                km\2\)
----------------------------------------------------------------------------------------------------------------
Harbor Seal.............................  Spring-Summer.............                  0.32                  0.17
Harbor Seal.............................  Fall-Winter...............                  0.83                  0.17
California Sea Lion.....................  Late Summer-Fall (post                      0.09                  0.09
                                           breeding season).
California Sea Lion.....................  Late Spring-Early Summer                    0.04                  0.04
                                           (breeding season).
Northern Elephant Seal..................  Late Spring-Early Winter..                  0.03                  0.03
Harbor Porpoise.........................  All Year..................                 0.021                 0.021
Gray Whale..............................  Late Winter and Spring....               0.00004               0.00004
----------------------------------------------------------------------------------------------------------------
Note: Densities for Pacific harbor seals, California sea lions and harbor porpoises are based on monitoring for
  the east span of the SFOBB from 2000 to 2013. Gray whale and elephant seal densities are estimated from
  sighting and stranding data from the MMC.

Estimated Takes by Pile Driving and Pile Removal

    The numbers of marine mammals by species that may be taken by pile 
driving were calculated by multiplying the ensonified area above a 
specific species exposure threshold by the days of the activity and by 
the estimated density of each species in the ensonified area. As 
discussed above threshold distances were determined based on previously 
measured distances to thresholds during the driving of 42-inch-diameter 
(1.07 meters) pipe piles. The same threshold distances have been 
applied to all types and sizes of piles proposed for installation and 
removal (i.e., sheet piles, H-piles, and pipe piles equal to or less 
than 36 inches [0.91 meter]). The take estimate is based on 132 days of 
pile driving to install 200 piles.
    For rare species of which the density estimates are unknown, such 
as northern fur seal and bottlenose dolphin, NMFS worked with CALTRANS 
and allotted 20 northern fur seals and 10 bottlenose dolphin for 
incidental take by Level B behavioral harassment to cover the chance 
encounter in case these animals happen to occur in the project area.
    A summary of estimated takes by in-water pile driving and pile 
removal is provided in Table 6.

[[Page 48758]]



  Table 6--Estimated Take of Marine Mammals From Pile Driving and Pile
                           Removal Activities
------------------------------------------------------------------------
                                              Level B
                                            Harassment        Level A
                 Species                    (Behavioral     Harassment
                                             Response)
------------------------------------------------------------------------
Pacific Harbor Seal.....................             862               0
California Sea Lion.....................             108               0
Northern Elephant Seal..................              13               0
Harbor Porpoise.........................              13               0
Gray Whale..............................               1               0
Northern fur seal.......................              20               0
Bottlenose dolphin......................              10               0
------------------------------------------------------------------------

    The number of marine mammals by species that may be taken by 
implosion of Piers E4 and E5 were calculated based on distances to the 
marine mammal threshold for explosions (Table 4) and the estimated 
density of each species in the ensonified areas (Table 5). A summary of 
estimated and requested takes by controlled implosion is provided in 
Table 8.

                    Table 7--Estimated Exposures of Marine Mammals to the Pier E4 and E5 Implosions for Levels A and B, and Mortality
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                 Level B Exposures                       Level A Exposures
                                                         --------------------------------------------------------------------------------
                         Species                                                                              Gastro-                        Mortality
                                                            Behavioral          TTS             PTS         intestinal      Slight lung
                                                             response                                      track injury       injury
--------------------------------------------------------------------------------------------------------------------------------------------------------
Pacific Harbor Seal.....................................               1               1               0               0               0               0
California Sea Lion.....................................               0               0               0               0               0               0
Northern Elephant Seal..................................               0               0               0               0               0               0
Harbor Porpoise.........................................               0               0               0               0               0               0
--------------------------------------------------------------------------------------------------------------------------------------------------------

    However, the number of marine mammals in the area at any given time 
is highly variable. Animal movement depends on time of day, tide 
levels, weather, and availability and distribution of prey species. 
Therefore, to account for potential high animal density that could 
occur during the short window of controlled implosion, NMFS worked with 
CALTRANS and adjusted the estimated number upwards for the requested 
takes. These adjustments were based on likely group sizes of these 
animals.
    A summary of estimated takes by implosion of Piers E4 and E5 is 
provided in Table 8.

  Table 8--Summary of Requested Takes of Marine Mammals for the Pier E4
                            and E5 Implosions
------------------------------------------------------------------------
                                              Level B
                 Species                    behavioral      Level B TTS
------------------------------------------------------------------------
Pacific harbor seal.....................              12               6
California sea lion.....................               3               2
Northern elephant seal..................               2               1
Harbor porpoise.........................               6               3
Northern fur seal.......................               1               1
Bottlenose dolphin......................               2               2
------------------------------------------------------------------------

    A summary of the request incidental takes of marine mammals for 
CALTRANS SFOBB construction activity, including from in-water pile 
driving/pile removal and controlled implosion for Piers E4 and E5 is 
provided in Table 9. These take estimates represent ``instances'' of 
take and are likely overestimates of the number of individual animals 
taken, since some individuals are likely taken on multiple days. The 
more likely the individuals are to remain in the action area for 
multiple days, the greater the overestimate of individuals.

                Table 9--Summary of Requested Takes of Marine Mammals for CALTRANS SFOBB Project
----------------------------------------------------------------------------------------------------------------
                                                      Level B                                      Percent take
                     Species                        behavioral      Level B TTS     Population      population
----------------------------------------------------------------------------------------------------------------
Pacific harbor seal.............................             874               6          30,968            2.84
California sea lion.............................             111               2         296,750            0.04
Northern elephant seal..........................              15               1         179,000            0.01
Harbor porpoise.................................              19               3           9,886            0.22
Northern fur seal...............................              21               1          12,844            0.17
Gray whale......................................               1               0          20,990            0.00

[[Page 48759]]

 
Bottlenose dolphin..............................              12               2             323            4.33
----------------------------------------------------------------------------------------------------------------

Analysis and Preliminary Determinations

Negligible Impact

    Negligible impact is ``an impact resulting from the specified 
activity that cannot be reasonably expected to, and is not reasonably 
likely to, adversely affect the species or stock through effects on 
annual rates of recruitment or survival'' (50 CFR 216.103). A 
negligible impact finding is based on the lack of likely adverse 
effects on annual rates of recruitment or survival (i.e., population-
level effects). An estimate of the number of 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, 
NMFS must consider other factors, such as the likely nature of any 
responses (their intensity, duration, etc.), the context of any 
responses (critical reproductive time or location, migration, etc.), as 
well as the number and nature of estimated Level A harassment takes, 
the number of estimated mortalities, and effects on habitat.
    To avoid repetition, this introductory discussion of our analyses 
applies to all the species listed in Table 9, given that the 
anticipated effects of CALTRANS' SFOBB construction activities 
involving pile driving and pile removal and controlled implosions for 
Piers E4 and E5 on marine mammals are expected to be relatively similar 
in nature. There is no information about the nature or severity of the 
impacts, or the size, status, or structure of any species or stock that 
would lead to a different analysis for this activity, or else species-
specific factors would be identified and analyzed.
    No injuries or mortalities are anticipated to occur as a result of 
CALTRANS' SFOBB construction activity associated with pile driving and 
pile removal and controlled implosion to demolish Piers E4 and E5, and 
none are proposed to be authorized. The relatively low marine mammal 
density and small Level A exclusion zones make injury takes of marine 
mammals unlikely, based on take calculation described above. In 
addition, the Level A exclusion zones would be thoroughly monitored 
before the proposed implosion, and detonation activity would be 
postponed if an marine mammal is sighted within the exclusion zone.
    The takes that are anticipated and authorized are expected to be 
limited to short-term Level B harassment (behavioral and TTS). Marine 
mammals (Pacific harbor seal, northern elephant seal, California sea 
lion, northern fur seal, gray whale, harbor porpoise, and bottlenose 
dolphin) present in the vicinity of the action area and taken by Level 
B harassment would most likely show overt brief disturbance (startle 
reaction) and avoidance of the area from elevated noise level during 
pile driving and pile removal and the implosion noise. A few marine 
mammals could experience TTS if they occur within the Level B TTS ZOI. 
However, as discussed early in this document, TTS is a temporary loss 
of hearing sensitivity when exposed to loud sound, and the hearing 
threshold is expected to recover completely within minutes to hours. 
Therefore, it is not considered an injury. In addition, even if an 
animal receives a TTS, the TTS would be a one-time event from a brief 
impulse noise (about 5 seconds), making it unlikely that the TTS would 
involve into PTS. Finally, there is no critical habitat or other 
biologically important areas in the vicinity of CALTRANS' proposed Pier 
E4 and E5 controlled implosion areas (Calambokidis et al., 2015).
    The project also is not expected to have significant adverse 
effects on affected marine mammals' habitat, as analyzed in detail in 
the ``Anticipated Effects on Marine Mammal Habitat'' section. There is 
no biologically important area in the vicinity of the SFOBB project 
area. The project activities would not permanently modify existing 
marine mammal habitat. The activities may kill some fish and cause 
other fish to leave the area temporarily, thus impacting marine 
mammals' foraging opportunities in a limited portion of the foraging 
range; but, because of the short duration of the activities and the 
relatively small area of the habitat that may be affected, the impacts 
to marine mammal habitat are not expected to cause significant or long-
term negative consequences.
    Based on the analysis contained herein of the likely effects of the 
specified activity on marine mammals and their habitat, and taking into 
consideration the implementation of the proposed monitoring and 
mitigation measures, NMFS preliminarily finds that the total marine 
mammal take from CALTRANS's SFOBB construction activity and the 
associated Piers E4 and E5 demolition via controlled implosion will 
have a negligible impact on the affected marine mammal species or 
stocks.

Small Number

    The requested takes represent less than 4.33% of all populations or 
stocks potentially impacted (see Table 9 in this document). These take 
estimates represent the percentage of each species or stock that could 
be taken by Level B behavioral harassment and TTS (Level B harassment). 
The numbers of marine mammals estimated to be taken are small 
proportions of the total populations of the affected species or stocks. 
In addition, the mitigation and monitoring measures (described 
previously in this document) prescribed in the proposed IHA are 
expected to reduce even further any potential disturbance to marine 
mammals.
    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, NMFS preliminarily finds 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 subsistence uses of marine mammals in the proposed 
project area; and, thus, no subsistence uses impacted by this action. 
Therefore, NMFS has determined that the total taking of affected 
species or stocks would not have an unmitigable adverse impact on the 
availability of such species or stocks for taking for subsistence 
purposes.

Endangered Species Act (ESA)

    NMFS has determined that issuance of the IHA will have no effect on 
listed marine mammals, as none are known to occur in the action area.

[[Page 48760]]

National Environmental Policy Act (NEPA)

    NMFS prepared an Environmental Assessment (EA) for the take of 
marine mammals incidental to construction of the East Span of the SFOBB 
and made a Finding of No Significant Impact (FONSI) on November 4, 
2003. Due to the modification of part of the construction project and 
the mitigation measures, NMFS reviewed additional information from 
CALTRANS regarding empirical measurements of pile driving noises for 
the smaller temporary piles without an air bubble curtain system and 
the use of vibratory pile driving. NMFS prepared a Supplemental 
Environmental Assessment (SEA) and analyzed the potential impacts to 
marine mammals that would result from the modification of the action. A 
Finding of No Significant Impact (FONSI) was signed on August 5, 2009. 
In addition, for CALTRANS' Piers E4 and E5 demolition using controlled 
implosion, NMFS prepared an SEA and analyzed the potential impacts to 
marine mammals that would result from the modification. A Finding of No 
Significant Impact (FONSI) was signed on September 3, 2015. The 
proposed activity and expected impacts remain within what was 
previously analyzed in the EA and SEAs. Therefore, no additional NEPA 
analysis is warranted. A copy of the SEA and FONSI is available upon 
request (see ADDRESSES).

Proposed Authorization

    As a result of these preliminary determinations, NMFS proposes to 
issue an IHA to CALTRANS for conducting SFOBB activities involving pile 
driving and pile removal, as well as Piers E4 and E5 demolition via 
controlled implosion, provided the previously mentioned mitigation, 
monitoring, and reporting requirements are incorporated. The proposed 
IHA language is provided next.
    1. This Authorization is valid from August 15, 2016, through August 
14, 2017.
    2. This Authorization is valid only for activities associated with 
the SFOBB activities and demolition activities in San Francisco Bay.
    3. (a) The species authorized for incidental harassment takings, 
Level B harassment only, are: Pacific harbor seal (Phoca vitulina 
richardii), California sea lion (Zalophus californianus), northern 
elephant seal (Mirounga angustirostris), northern fur seal (Callorhinus 
ursinus), gray whale (Eschrichtius robustus), harbor porpoise (Phocoena 
phocoena), and bottlenose dolphin (Tursiops truncatus).
    (b) The authorization for taking by harassment is limited to the 
following acoustic sources and from the following activities:
     In-water pile driving and pile removal activities; and
     Piers E4 and E5 demolition via controlled implosion and 
associated test blasting.
    (c) The taking of any marine mammal in a manner prohibited under 
this Authorization must be reported within 24 hours of the taking to 
the West Coast Administrator (206-526-6150), National Marine Fisheries 
Service (NMFS) and the Chief of the Permits and Conservation Division, 
Office of Protected Resources, NMFS, at (301) 427-8401, or her designee 
(301-427-8418).
    4. The holder of this Authorization must notify the Chief of the 
Permits and Conservation Division, Office of Protected Resources, at 
least 48 hours prior to the start of activities identified in 3(b) 
(unless constrained by the date of issuance of this Authorization in 
which case notification shall be made as soon as possible).
    5. Prohibitions
    (a) The taking, by incidental harassment only, is limited to the 
species listed under condition 3(a) above and by the numbers listed in 
Table 9 of this notice. The taking by Level A harassment, injury or 
death of these species or the taking by harassment, injury or death of 
any other species of marine mammal is prohibited and may result in the 
modification, suspension, or revocation of this Authorization.
    (b) The taking of any marine mammal is prohibited whenever the 
required protected species observers (PSOs), required by condition 
7(a), are not present in conformance with condition 7(a) of this 
Authorization.
    6. Mitigation
    (a) Time Restriction
    In-water pile driving and pile removal activities and the 
controlled implosion of Piers E4 and E5 shall only be conducted during 
daylight hours and with enough time for pre and post activity 
monitoring, and with good visibility when the largest exclusion zone 
can be visually monitored.
    (b) Installation of Sound Attenuation Systems
    (i) For in-water pile driving, energy attenuator (such as air 
bubble curtain system or dewatered cofferdam) shall be used for all 
impact pile driving of pipe piles, with the exception of pile proofing 
and H-piles.
    (ii) For controlled implosion of Piers E4 and E5, CALTRANS should 
install a Blast Attenuation System (BAS) prior to demolition to reduce 
the shockwave from the implosion.
    (c) Establishment of Exclusion Zones and Zones of Influence
    (i) For in-water pile driving and pile removal activities, CALTRANS 
shall establish exclusion zones where received underwater sound 
pressure levels (SPLs) are higher than 180 dB (rms) and 190 dB (rms) re 
1 [mu]Pa for cetaceans and pinnipeds, respectively, and zones of 
influence (ZOIs) where received underwater sound pressure levels (SPLs) 
are higher than 160 dB (rms) and 120 dB (rms) re 1 [mu]Pa for impulse 
noise sources (impact pile driving) and non-impulses noise sources 
(vibratory pile driving), respectively. The isopleth of these zones are 
provided in Table 2.
    (ii) For Piers E4 and E5 controlled implosion and associated test 
blasting, CALTRANS shall establish exclusions zones and ZOIs that are 
appropriate to specific marine mammal functional hearing group shall be 
established. The isopleth of these zones are provided in Table 3.
    (d) Exclusion Zone Monitoring for Mitigation Measures.
    (i) NMFS-approved protected species observers (PSOs) shall conduct 
initial survey of the exclusion for 30 minutes to ensure that no marine 
mammals are seen within the zones before impact pile driving and 
controlled implosion.
    (ii) If marine mammals are found within the exclusion zones, impact 
pile driving and/or controlled implosion of the piers shall be delayed 
until they move out of the area. If a marine mammal is seen above water 
and then dives below, the contractor would wait 15 minutes for 
pinnipeds and small cetacean (harbor porpoise) and harbor porpoise and 
30 minutes for gray whale and bottlenose dolphin. If no marine mammals 
are seen by the observer in that time it would be assumed that the 
animal has moved beyond the exclusion zone.
    (iii) If the time between pile-segment driving is less than 30 
minutes, a new 30-minute survey is unnecessary provided marine mammal 
monitors continue observations during the interruption. If pile driving 
ceases for 30 minutes or more and a marine mammal is sighted within the 
designated safety zone(s) prior to the commencement of pile-driving, 
the PSO(s) must notify the Resident Engineer (or other authorized 
individual) immediately and implement measures in condition 5(d)(ii).
    (e) Soft Start
    CALTRANS and its contractor shall implement soft start, i.e., 
starting the pile driving hammer at the lowest power setting and 
gradually ramp up to

[[Page 48761]]

full power, prior to operating pile driving hammers at full capacity 
for both impact and vibratory pile driving.
    (f) Shut-down
    For pile driving activities, if a marine mammal is sighted within 
the exclusion zone or is approaching the exclusion zone after pile-
driving has begun, pile driving shall be shut-down. CALTRANS may resume 
pile driving after a shut-down measure following condition 5(d)(ii).
    (g) Communication
    For controlled implosion, the Lead PSO shall be in constant contact 
with the Resident Engineer on site and the blasting crew to ensure that 
no marine mammal is within the exclusion zone before the controlled 
implosion.
    7. Monitoring:
    (a) Protected Species Observers.
    (i) CALTRANS shall employ NMFS-approved PSOs to conduct marine 
mammal monitoring for its SFOBB construction activities that involve 
in-water pile driving and pile removal and controlled pier implosion.
    (ii) Marine mammal monitoring shall begin at least 30 minutes prior 
to the start of the activities, through the entire activities, and 
continue to 30 minutes after the construction activities and 60 minutes 
after the implosion events.
    (iii) Observations shall be made using high-quality binoculars 
(e.g., Zeiss, 10 x 42 power). PSOs shall be equipped with radios or 
cell phones for maintaining contact with other observers and CALTRANS 
engineers, and range finders to determine distance to marine mammals, 
boats, buoys, and construction equipment.
    (iv) For in-water pile driving and pile removal.
    (A) CALTRANS shall implement onsite marine mammal monitoring for 
100% of all unattenuated impact pile driving of H-piles for 180- and 
190-dB re 1 [mu]Pa exclusion zones and 160-dB re 1 [mu]Pa Level B 
harassment zone, and attenuated impact pile driving of pipe piles 
(except pile proofing) for 180- and 190-dB re 1 [mu]Pa exclusion zones.
    (B) CALTRANS shall also monitor 20% of the attenuated impact pile 
driving for the 160-dB re 1 [mu]Pa Level B harassment zone, and 20% of 
vibratory pile driving for the 120 dB re 1 [mu]Pa Level B harassment 
zone.
    (C) Data on all observations would be recorded and shall include 
the following information:
     Location of sighting;
     Species;
     Number of individuals;
     Number of calves present;
     Duration of sighting;
     Behavior of marine animals sighted;
     Direction of travel;
     When in relation to construction activities did the 
sighting occur (e.g., before, ``soft-start'', during, or after the pile 
driving or removal); and
     Other human activities in the area.
    (v) For controlled implosion of Piers E4 and E5:
    (A) A minimum of 8-10 PSOs shall be required during the Piers E4 
and E5 controlled implosion so that the exclusion zone, Level B 
Harassment TTS and Behavioral ZOIs, and surrounding area can be 
monitored.
    (B) PSOs shall be positioned near the edge of each of the threshold 
criteria zones and shall utilize boats, barges, and bridge piers and 
roadway.
    (C) The Lead PSO shall be in constant communication with the 
Environmental Compliance Manager that will be located with the CALTRANS 
Engineer and the Blasting Supervisor (or person that will be in charge 
of detonating the charges) during the implosion.
    (D) Boat or shore surveys shall be conducted immediately after the 
event and for the three days following the event to determine if there 
are any injured or stranded marine mammals in the area.
    (E) Monitoring Data Collection:
    For each marine mammal sighting, the following shall be recorded, 
if possible:
     Species.
     Number of animals (with or without pup/calf).
     Age class (pup/calf, juvenile, adult).
     Identifying marks or color (scars, red pelage, damaged 
dorsal fin, etc.).
     Position relative to Pier E4 or E5 (distance and 
direction).
     Movement (direction and relative speed).
     Behavior (logging [resting at the surface], swimming, 
spyhopping [raising above the water surface to view the area], 
foraging, etc.)
     Duration of sighting or times of multiple sightings of the 
same individual
    8. Reporting:
    (a) CALTRANS shall submit a draft monitoring report within 90 days 
after completion of the construction work or the expiration of the IHA 
(if issued), whichever comes earlier. This report would detail the 
monitoring protocol, summarize the data recorded during monitoring, and 
estimate the number of marine mammals that may have been harassed.
    (b) NMFS would have an opportunity to provide comments within 30 
days after receiving the draft report, and if NMFS has comments, 
CALTRANS shall address the comments and submit a final report to NMFS 
within 30 days.
    (c) If NMFS does not provide comments within 30 days after 
receiving the report, the draft report is considered to be final.
    (d) In the unanticipated event that the construction activities 
clearly cause the take of a marine mammal in a manner prohibited by 
this Authorization (if issued), such as an injury, serious injury, or 
mortality, CALTRANS shall immediately cease all operations and 
immediately report the incident to the Chief, Permits and Conservation 
Division, Office of Protected Resources, NMFS, and the West Coast 
Regional Stranding Coordinators. The report must include the following 
information:
    (i) Time, date, and location (latitude/longitude) of the incident;
    (ii) Description of the incident;
    (iii) Status of all sound source use in the 24 hours preceding the 
incident;
    (iv) Environmental conditions (e.g., wind speed and direction, sea 
state, cloud cover, visibility, and water depth);
    (v) Description of marine mammal observations in the 24 hours 
preceding the incident;
    (vi) Species identification or description of the animal(s) 
involved;
    (vii) The fate of the animal(s); and
    (viii) Photographs or video footage of the animal (if equipment is 
available).
    Activities shall not resume until NMFS is able to review the 
circumstances of the prohibited take. NMFS shall work with CALTRANS to 
determine what is necessary to minimize the likelihood of further 
prohibited take and ensure MMPA compliance. CALTRANS may not resume 
their activities until notified by NMFS via letter, email, or 
telephone.
    (e) In the event that CALTRANS discovers an injured or dead marine 
mammal, and the lead PSO determines that the cause of the injury or 
death is unknown and the death is relatively recent (i.e., in less than 
a moderate state of decomposition as described in the next paragraph), 
CALTRANS will immediately report the incident to the Chief, Permits and 
Conservation Division, Office of Protected Resources, NMFS, and the 
West Coast Regional Stranding Coordinators. The report must include the 
same information identified above. Activities may continue while NMFS 
reviews the circumstances of the incident. NMFS will work with CALTRANS 
to determine whether modifications in the activities are appropriate.
    (f) In the event that CALTRANS discovers an injured or dead marine 
mammal, and the lead PSO 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

[[Page 48762]]

to advanced decomposition, or scavenger damage), CALTRANS shall report 
the incident to the Chief, Permits and Conservation Division, Office of 
Protected Resources, NMFS, and the West Coast Regional Stranding 
Coordinators, within 24 hours of the discovery. CALTRANS shall provide 
photographs or video footage (if available) or other documentation of 
the stranded animal sighting to NMFS and the Marine Mammal Stranding 
Network. CALTRANS can continue its operations under such a case.
    9. Marine Mammal Stranding Plan:
    A marine mammal stranding plan shall be prepared in cooperation 
with the local NMFS-designated marine mammal stranding, rescue, and 
rehabilitation center. Elements of that plan would include the 
following:
    (a) The stranding crew shall prepare treatment areas at the NMFS-
designated facility for cetaceans or pinnipeds that may be injured from 
the implosion. Preparation shall include equipment to treat lung 
injuries, auditory testing equipment, dry and wet caged areas to hold 
animals, and operating rooms if surgical procedures are necessary. 
Equipment to conduct auditory brainstem response hearing testing would 
be available to determine if any inner ear threshold shifts (TTS or 
PTS) have occurred.
    (b) A stranding crew and a veterinarian shall be on call near the 
Piers E4 and E5 sites at the time of the implosion to quickly recover 
any injured marine mammals, provide emergency veterinary care, 
stabilize the animal's condition, and transport individuals to the 
NMFS-designated facility. If an injured or dead animal is found, NMFS 
(both the regional office and headquarters) shall be notified 
immediately even if the animal appears to be sick or injured from other 
than blasting.
    (c) Post-implosion surveys shall be conducted immediately after the 
event and over the following three days to determine if there are any 
injured or dead marine mammals in the area.
    (d) Any veterinarian procedures, euthanasia, rehabilitation 
decisions and time of release or disposition of the animal shall be at 
the discretion of the NMFS-designated facility staff and the 
veterinarians treating the animals. Any necropsies to determine if the 
injuries or death of an animal was the result of the blast or other 
anthropogenic or natural causes will be conducted at the NMFS-
designated facility by the stranding crew and veterinarians. The 
results shall be communicated to both CALTRANS and to NMFS as soon as 
possible with a written report within a month.
    10. 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, or if there is an 
unmitigable adverse impact on the availability of such species or 
stocks for subsistence uses.
    11. A copy of this Authorization must be in the possession of each 
contractor who performs the in-water pile driving, pile removal, and 
Piers E4 and E5 controlled implosion work.

    Dated: July 21, 2016.
Donna S. Wieting,
Director, Office of Protected Resources, National Marine Fisheries 
Service.
[FR Doc. 2016-17617 Filed 7-25-16; 8:45 am]
 BILLING CODE 3510-22-P