[Federal Register Volume 78, Number 191 (Wednesday, October 2, 2013)]
[Notices]
[Pages 60852-60860]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2013-24079]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

RIN 0648-XC833


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.

[[Page 60853]]


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 California sea lions, Pacific harbor seals, harbor 
porpoises, and gray whales, by harassment, incidental to construction 
activities associated with the East Span of the San Francisco-Oakland 
Bay Bridge (SF-OBB) in 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 November 
1, 2013.

ADDRESSES: Comments on the application should be addressed to Michael 
Payne, Chief, Permits and Conservation Division, Office of Protected 
Resources, National Marine Fisheries Service, 1315 East-West Highway, 
Silver Spring, MD 20910-3225. 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 10-
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#applications 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.
    The application used in this document may be obtained by visiting 
the internet at: http://www.nmfs.noaa.gov/pr/permits/incidental.htm#applications. 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 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 April 15, 2013, CALTRANS submitted a request to NOAA requesting 
an IHA for the possible harassment of small numbers of California sea 
lions (Zalophus californianus), Pacific harbor seals (Phoca vitulina 
richardsii), harbor porpoises (Phocoena phocoena), and gray whales 
(Eschrichtius robustus) incidental to construction associated with a 
replacement bridge for the East Span of the SF-OBB, in San Francisco 
Bay (SFB, or Bay), California. The proposed construction activities 
would last for approximately three years, starting 2013.

Description of the Specified Activity

    An IHA was previously issued to CALTRANS for this activity on 
January 8, 2013 (78 FR 2371; January 11, 2013), based on activities 
described on CALTRANS' IHA application dated April 23, 2012. The 
current IHA expires on January 7, 2014. Since the construction activity 
would last for approximately additional two years after the expiration 
of the current IHA, CALTRANS requests to renew its IHA. In its IHA 
renewal request, CALTRANS also states that there has been no change in 
the scope of work for the SF-OBB Project from what was outlined in its 
April 23, 2012, IHA application project description, the Federal 
Register notice for the proposed IHA (77 FR 50473; August 21, 2012), 
and the Federal Register notice for the issuance of that IHA (78 FR 
2371; January 11, 2013). Refer to these documents for a detailed 
description of CALTRANS' SF-OBB construction activities.
    Since the issuance of the IHA, there has been no in-water pile 
driving or dismantling activity.

Description of Marine Mammals in the Area of the Specified Activity

    General information on the marine mammal species found in 
California waters can be found in Caretta et al. (2013), which is 
available at the following URL: http://www.nmfs.noaa.gov/pr/sars/pdf/po2012.pdf. Refer to that document for information on these species.
    The marine mammals most likely to be found in the SF-OBB area are 
the California sea lion, Pacific harbor seal, and harbor porpoise. From 
December through May gray whales may also be present in the SF-OBB 
area. Information on California sea lion, harbor seal, and gray whale 
was provided in the November 14, 2003 (68 FR 64595), Federal Register 
notice; information on harbor porpoise was provided in the January 26, 
2006 (71 FR 4352), Federal Register notice.

Potential Effects on Marine Mammals and Their Habitat

    CALTRANS and NMFS have determined that open-water pile driving and 
pile removal, as well as dredging and dismantling of concrete 
foundation of existing bridge by saw cutting, flame cutting, mechanical 
splitting, drilling, pulverizing and/or hydro-cutting, as outlined in 
the project description, have the potential to result in behavioral 
harassment of California sea lions, Pacific harbor seals, harbor 
porpoises, and gray whales that may be swimming, foraging, or resting 
in the project vicinity while pile driving is being conducted. Pile 
driving and removal could potentially harass those few pinnipeds that 
are in the water close to

[[Page 60854]]

the project site, whether their heads are above or below the surface.
    Marine mammals exposed to high intensity sound repeatedly or for 
prolonged periods can experience hearing threshold shift (TS), which is 
the loss of hearing sensitivity at certain frequency ranges (Kastak et 
al. 1999; Schlundt et al. 2000; Finneran et al. 2002; 2005). TS can be 
permanent (PTS), in which case the loss of hearing sensitivity is 
unrecoverable, or temporary (TTS), in which case the animal's hearing 
threshold will recover over time (Southall et al. 2007). Since marine 
mammals depend on acoustic cues for vital biological functions, such as 
orientation, communication, finding prey, and avoiding predators, 
marine mammals that incur PTS or TTS may have reduced fitness in 
survival and reproduction, either permanently or temporarily. Repeated 
noise exposure that leads to TTS could cause PTS.
    Measured source levels from impact pile driving can be as high as 
214 dB re 1 [mu]Pa @ 1 m. Although no marine mammals have been shown to 
experience TTS or PTS as a result of being exposed to pile driving 
activities, experiments on a bottlenose dolphin (Tursiops truncates) 
and beluga whale (Delphinapterus leucas) showed that exposure to a 
single watergun pulse at a received level of 207 kPa (or 30 psi) peak-
to-peak (p-p), which is equivalent to 228 dB (p-p) re 1 [mu]Pa, 
resulted in a 7 and 6 dB TTS in the beluga whale at 0.4 and 30 kHz, 
respectively. Thresholds returned to within 2 dB of the pre-exposure 
level within 4 minutes of the exposure (Finneran et al. 2002). No TTS 
was observed in the bottlenose dolphin. Although the source level of 
pile driving from one hammer strike is expected to be much lower than 
the single watergun pulse cited here, animals exposed for a prolonged 
period to repeated hammer strikes could receive more noise exposure in 
terms of sound exposure level (SEL) than from the single watergun pulse 
(estimated at 188 dB re 1 [mu]Pa\2\-s) in the aforementioned experiment 
(Finneran et al. 2002).
    Noises from dismantling of marine foundations by mechanical means 
include, but are not limited to, saw cutting, mechanical splitting, 
drilling and pulverizing. Saw cutting and drilling constitute non-pulse 
noise, whereas mechanical splitting and pulverizing constitute impulse 
noise. Although the characteristics of these noises are not well 
studied, noises from saw cutting and drilling are expected to be 
similar to vibratory pile driving, and noises from mechanical splitting 
and pulverizing are expected to be similar to impact pile driving, but 
at lower intensity, due to the similar mechanisms in sound generating 
but at a lower power outputs. CALTRANS states that drilling and saw 
cutting are anticipated to produce underwater sound pressure levels 
(SPLs) in excess of 120 dB RMS, but are not anticipated to exceed the 
180 dB re 1 [mu]Pa (RMS). The mechanical splitting and pulverizing of 
concrete with equipment such as a hammer hoe has the potential to 
generate high sound pressure levels in excess of 190 dB re 1 [mu]Pa 
(RMS) at 1 m.
    However, in order for marine mammals to experience TTS or PTS, the 
animals have to be close enough to be exposed to high intensity noise 
levels for prolonged period of time. Based on the best scientific 
information available, the expected received sound levels are far below 
the threshold that could cause TTS or the onset of PTS.
    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. 
Masking can interfere with detection of acoustic signals such as 
communication calls, echolocation sounds, and environmental sounds 
important to marine mammals. Therefore, under certain circumstances, 
marine mammals whose acoustical sensors or environment are being 
severely masked could also be impaired from maximizing their 
performance fitness in survival and reproduction.
    Masking occurs at the frequency band which the animals utilize. 
Therefore, since noise generated from in-water pile driving during the 
SF-OBB construction activities is mostly concentrated at low frequency 
ranges, it may have less effect on high frequency echolocation sounds 
by harbor porpoises. However, lower frequency 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 can potentially impact 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 SPL) in the world's ocean from pre-industrial periods, and most of 
these increases are from distant shipping (Hildebrand 2009). All 
anthropogenic noise sources, such as those from vessels traffic, pile 
driving, dredging, and dismantling existing bridge by mechanic means, 
contribute to the elevated ambient noise levels, thus intensifying 
potential for masking.
    Nevertheless, the sum of noise from the proposed SF-OBB 
construction activities is confined in an area of inland waters (San 
Francisco Bay) that is bounded by landmass, therefore, the noise 
generated is not expected to contribute to increased ocean ambient 
noise. Due to shallow water depth near the Oakland shore, dredging 
activities are mainly used to create a barge access channel to 
dismantle the existing bridge. Therefore, underwater sound propagation 
from dredging is expected to be poor due to the extremely shallowness 
of the area to be dredged.
    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), especially if the detected disturbances appear minor. 
However, the consequences of behavioral modification could be expected 
to be biologically significant if the change affects growth, survival, 
or reproduction. Some of these significant behavioral modifications 
include:
     Drastic change in diving/surfacing patterns (such as those 
thought to be causing beaked whale stranding due to exposure to 
military mid-frequency tactical sonar);
     Habitat abandonment due to loss of desirable acoustic 
environment; and
     Cessation of feeding or social interaction.
    The proposed project area is not believed to be a prime habitat for 
marine mammals, nor is it considered an area frequented by marine 
mammals.

[[Page 60855]]

Therefore, behavioral disturbances that could result from anthropogenic 
noise associated with SF-OBB construction activities are expected to 
affect only a limited number of marine mammals on an infrequent basis.
    Currently NMFS uses 160 dB re 1 [mu]Pa (RMS) at received level for 
impulse noises (such as impact pile driving, mechanic splitting and 
pulverizing) as the onset of marine mammal behavioral harassment, and 
120 dB re 1 [mu]Pa (RMS) for non-impulse noises (vibratory pile 
driving, saw cutting, drilling, and dredging).
    As far as airborne noise is concerned, based on airborne noise 
levels measured and on-site monitoring conducted during 2004 under a 
previous IHA, noise levels from the East Span project did not result in 
the harassment of harbor seals hauled out on Yerba Buena Island (YBI). 
Also, noise levels from the East Span project are not expected to 
result in harassment of the sea lions hauled out at Pier 39 as airborne 
and waterborne sound pressure levels (SPLs) would attenuate to levels 
below where harassment would be expected by the time they reach that 
haul-out site, 5.7 km (3.5 miles) from the project site. Therefore, no 
pinniped hauled out would be affected as a result of the proposed pile-
driving. A detailed description of the acoustic measurements is 
provided in the 2004 CALTRANS marine mammal and acoustic monitoring 
report for the same activity (CALTRANS 2005).
    Short-term impacts to habitat may include minimal disturbance of 
the sediment where individual bridge piers are constructed. Long-term 
impacts to marine mammal habitat will be limited to the footprint of 
the piles and the obstruction they will create following installation. 
However, this impact is not considered significant as the marine 
mammals can easily swim around the piles of the new bridge, as they 
currently swim around the existing bridge piers.

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.
    For the proposed CALTRANS SF-OBB 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 Level B behavioral of marine mammals would be reduced to the 
lowest level practicable.

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.

Establishment of Exclusion and Level B Harassment Zones

    Before the commencement of in-water construction activities, which 
include impact pile driving, vibratory pile driving, and mechanical 
dismantling of existing bridge, CALTRANS shall establish exclusion 
zones where received underwater sound pressure levels (SPLs) are higher 
than 180 dB (rms) and 190 dB (rms) re 1 [micro]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 [micro]Pa for impulse noise sources (impact 
pile driving) and non-impulses noise sources (vibratory pile driving 
and mechanic dismantling), respectively. Before the sizes of actual 
zones are determined based on hydroacoustic measurements, CALTRANS 
shall establish these zones based on prior measurements conducted 
during SF-OBB constructions, as described in Table 1 of this document.

                      Table 1--Temporary Exclusion and Level B Harassment Zones for Various Pile Driving and Dismantling Activities
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                              Distance to     Distance to     Distance to     Distance to
                                                                              120 dB re 1     160 dB re 1     180 dB re 1     190 dB re 1
    Pile driving/dismantling activities             Pile size  (m)             [micro]Pa       [micro]Pa       [micro]Pa       [micro]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
Dismantling...............................  ..............................           2,000              NA             100             100
--------------------------------------------------------------------------------------------------------------------------------------------------------

    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 harbor porpoise and 
30 minutes for 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

[[Page 60856]]

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).
    Once the pile driving of a segment begins it cannot be stopped 
until that segment has reached its predetermined depth due to the 
nature of the sediments underlying the Bay. If pile driving stops and 
then resumes, it would potentially have to occur for a longer time and 
at increased energy levels. In sum, this would simply amplify impacts 
to marine mammals, as they would endure potentially higher SPLs for 
longer periods of time. Pile segment lengths and wall thickness have 
been specially designed so that when work is stopped between segments 
(but not during a single segment), the pile tip is never resting in 
highly resistant sediment layers. Therefore, because of this 
operational situation, if seals, sea lions, or harbor porpoises enter 
the safety zone after pile driving of a segment has begun, pile driving 
will continue and marine mammal observers will monitor and record 
marine mammal numbers and behavior. However, 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 follow the mitigation 
requirements as outlined previously in this document.

Soft Start

    Although marine mammals will be protected from Level A harassment 
(i.e., injury) through marine mammal observers monitoring a 190-dB 
exclusion zone for pinnipeds and 180-dB exclusion zone for cetaceans, 
mitigation may not be 100 percent effective at all times in locating 
marine mammals. Therefore, 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 potential injury, 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.

Power Down and Shut-Down

    As mentioned previously, although power down and shut-down measures 
will not be required for pile driving and removal activities, these 
measures are required for mechanical dismantling of the existing 
bridge. The contractor perform mechanical dismantling work will stop 
in-water noise generating machinery when marine mammals are sighted 
within the designated exclusion zones.

Proposed Monitoring and Reporting Measures

    In order to issue an 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.

Visual Monitoring

    Besides using monitoring for implementing power down and shut-down 
measures for mechanical bridge dismantling, 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 [micro]Pa exclusion zones and 160-dB re 1 
[micro]Pa Level B harassment zone, attenuated impact pile driving 
(except pile proofing) and mechanical dismantling for 180- and 190-dB 
re 1 [micro]Pa exclusion zones. CALTRANS will also monitor 20% of the 
attenuated impact pile driving for the 160-dB re 1 [micro]Pa Level B 
harassment zone, and 20% of vibratory pile driving and mechanic 
dismantling for the 120-dB re 1 [micro]Pa Level B harassment zone.
    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.
    Data on all observations will be recorded and will include the 
following information:
    (1) Location of sighting;
    (2) species;
    (3) number of individuals;
    (4) number of calves present;
    (5) duration of sighting;
    (6) behavior of marine animals sighted;
    (7) direction of travel;
    (8) when in relation to construction activities did the sighting 
occur (e.g., before, ``soft-start'', during, or after the pile driving 
or removal).
    The reactions of marine mammals will be recorded based on the 
following classifications that are consistent with the Richmond Bridge 
Harbor Seal survey methodology (for information on the Richmond Bridge 
authorization, see 68 FR 66076, November 25, 2003): (1) No response, 
(2) head alert (looks toward the source of disturbance), (3) approach 
water (but not leave), and (4) flush (leaves haul-out site). The number 
of marine mammals under each disturbance reaction will be recorded, as 
well as the time when seals re-haul after a flush.

Hydroacoustic Monitoring

    The purpose of the underwater sound monitoring during dismantling 
of concrete foundations via mechanical means is to establish the 
exclusion zones of 180 dB re 1 [mu]Pa (rms) for cetaceans and 190 dB re 
1 [mu]Pa (rms) for pinnipeds. Monitoring will occur during the initial 
use of concrete dismantling equipment with the potential to generate 
sound pressure levels in excess of 180 dB re 1 [mu]Pa (rms). Monitoring 
will likely be conducted from construction barges and/or boats. 
Measurements will be taken at various distances as needed to determine 
the distance to the 180 and 190 dB re 1 [mu]Pa (rms) contours.
    The purpose of underwater sound monitoring during impact pile 
driving will be to verify sound level estimates and confirm that sound 
levels do not equal or exceed 180 dB re 1 [mu]Pa (rms).

Reporting

    CALTRANS will notify NMFS prior to the initiation of the pile 
driving and dismantling activities for the removal of the existing east 
span. NMFS will be informed of the initial sound pressure level 
measurements for both pile driving and foundation dismantling 
activities, including the final exclusion zone and Level B harassment 
zone radii established for impact and vibratory pile driving and marine 
foundation dismantling activities.
    Monitoring reports will be posted on the SFOBB Project's biological 
mitigation Web site (www.biomitigation.org) on a weekly

[[Page 60857]]

basis if in-water construction activities are conducted. Marine mammal 
monitoring reports will include species and numbers of marine mammals 
observed, time and location of observation and behavior of the animal. 
In addition, the reports will include an estimate of the number and 
species of marine mammals that may have been harassed as a result of 
activities.
    In addition, CALTRANS will provide NMFS with a draft final report 
within 90 days after the expiration of the IHA. This report should 
detail the monitoring protocol, summarize the data recorded during 
monitoring, and estimate the number of marine mammals that may have 
been harassed due to pile driving. If no comments are received from 
NMFS within 30 days, the draft final report will constitute the final 
report. If comments are received, a final report must be submitted 
within 30 days after receipt of comments.
    In addition, NMFS would require CALTRANS to notify NMFS' Office of 
Protected Resources and NMFS' Stranding Network within 48 hours of 
sighting an injured or dead marine mammal in the vicinity of the 
construction site. CALTRANS shall provide NMFS with the species or 
description of the animal(s), the condition of the animal(s) (including 
carcass condition if the animal is dead), location, time of first 
discovery, observed behaviors (if alive), and photo or video (if 
available).
    In the event that an injured or dead marine mammal is found by 
CALTRANS that is not in the vicinity of the SF-OBB construction site, 
CALTRANS would report the same information as listed above as soon as 
operationally feasible to NMFS.

Marine Mammal Monitoring Report From Previous IHA

    Prior marine mammal monitoring during CALTRANS' pile driving 
activities and weekly marine mammal observation memorandums (CALTRANS 
2007; 2010) indicate that only a small number of harbor seals (a total 
of 16 individuals since 2006) and 1 California sea lion (a total of 1 
individual in 2009) were observed within zones of influence (ZOIs) that 
could result in behavioral harassment. However, the reports state that 
none of the animals were observed as been startled by the exposure, 
which could be an indication that these animals were habituated to 
human activities in San Francisco Bay. In addition, no harbor porpoise 
or gray whales were observed during pile driving activities associated 
to CALTRANS' SF-OBB construction work.

Estimated Take by Incidental Harassment

    Marine mammal take estimates are based on marine mammal monitoring 
reports and marine mammal observations made during pile driving 
activities associated with the SF-OBB construction work authorized 
under prior IHAs. For pile driving activities conducted in 2006, 5 
harbor seals and no other marine mammals were detected within the 
isopleths of 160 dB (rms) re 1 [mu]Pa during impact pile driving where 
air bubble curtains were deployed for mitigation measures (radius of 
ZOI at 500 m) (CALTRANS 2007). For pile driving activities conducted in 
the 2008 and 2009 seasons, CALTRANS monitored a much larger ZOI of 120 
dB (rms) re 1 [mu]Pa as a result of vibratory pile driving. A total of 
11 harbor seals and 1 California sea lion were observed entering the 
120 dB (rms) re 1 [mu]Pa ZOI (CALTRANS). However, despite the ZOI being 
monitored extended to 1,900 m for the 120 dB isopleths, CALTRANS did 
not specify which pile driving activities conducted in 2008 and 2009 
used an impact hammer and which ones used a vibratory hammer. 
Therefore, at least some of these animals were not exposed to received 
level above 160 dB (rms) re [mu]Pa, and thus should not be considered 
as ``taken'' under the MMPA. No harbor porpoise or gray whales were 
observed during pile driving activities associated to CALTRANS' SF-OBB 
construction work (CALTRANS 2007; 2010).
    Based on these results, and accounting for a certain level of 
uncertainty regarding the next phase of construction, NMFS concludes 
that at maximum 50 harbor seals, 10 California sea lions, 10 harbor 
porpoises, and 5 gray whales could be exposed to noise levels that 
could cause Level B harassment as a result of the CALTRAN' SF-OBB 
construction activities (Table 2). These numbers represent 0.17%, 
0.00%, 0.03%, and 0.11% of the California stock harbor seal, the U.S. 
stock California sea lion, the Eastern North Pacific stock gray whale, 
and the San Francisco-Russian River stock harbor porpoise, respectively 
(Table 2).

 Table 2--Estimates of the Possible Maximum Numbers of Marine Mammals Taken by Level B Harassment as a Result of
                              the Proposed CALTRANS' SF-OBB Construction Activities
----------------------------------------------------------------------------------------------------------------
               Species                          Stocks               Level B takes          Percent population
----------------------------------------------------------------------------------------------------------------
Harbor seal..........................  California.............                       50                     0.17
California sea lion..................  U.S....................                       10                     0.00
Gray whale...........................  Eastern North Pacific..                        5                     0.03
Harbor porpoise......................  San Francisco-Russian                         10                     0.11
                                        River.
----------------------------------------------------------------------------------------------------------------

Negligible Impact and Small Numbers Analyses and Preliminary 
Determinations

    As a preliminary matter, we typically include our negligible impact 
and small numbers analyses and determinations under the same section 
heading of our Federal Register Notices. Despite co-locating these 
terms, we acknowledge that negligible impact and small numbers are 
distinct standards under the MMPA and treat them as such. The analysis 
presented below does not conflate the two standards; instead, each has 
been considered independently and we have applied the relevant factors 
to inform our negligible impact and small numbers determinations.
    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.'' In making a negligible impact determination, 
NMFS considers a variety of factors, including but not limited to: (1) 
The number of anticipated mortalities; (2) the number and nature of 
anticipated injuries; (3) the number, nature, intensity, and duration 
of Level B harassment; and (4) the context in which the takes occur.
    The CALTRANS' specified activities have been described based on 
best estimates of the planned SF-OBB construction project within the 
proposed project area. Some of the noises that would be generated as a 
result of the proposed bridge construction and dismantling project,

[[Page 60858]]

such as impact pile driving, are high intensity. However, the in-water 
pile driving for the piles would use small hammers and/or vibratory 
pile driving methods, coupled with noise attenuation mechanism such as 
air bubble curtains for impact pile driving, therefore the resulting 
exclusion zones for potential TS are expected to be extremely small 
(<35 m) from the hammer. In addition, the source levels from vibratory 
pile driving are expected to be below the TS onset threshold. 
Therefore, NMFS does not expect that any animals would receive Level A 
(including injury) harassment or Level B harassment in the form of TTS 
from being exposed to in-water pile driving associated with SF-OBB 
construction project.
    Based on marine mammal monitoring reports under previous IHAs, only 
16 harbor seals and 1 California sea lion were observed within the 120 
dB (in 2008 and 2009) or 160 dB (in 2006) ZOIs during in-water pile 
driving since 2006. NMFS estimates that up to 50 harbor seals, 10 
California sea lions, 10 harbor porpoises, and 5 gray whales could be 
exposed to received levels above 120 dB (rms) during vibratory pile 
driving or 160 dB (rms) during impact pile driving for the next season 
of construction activities due to the large numbers of piles to be 
driven and the extended zones of influence from vibratory pile driving. 
These are relatively small numbers, representing 0.17% of the 
California stock of harbor seal population (estimated at 30,196; 
Carretta et al. 2013), 0.00% of the U.S. stock of California sea lion 
population (estimated at 296,750; Carretta et al. 2013), 0.11% of the 
San Francisco-Russian River stock of harbor porpoise population 
(estimated at 9,189; Carretta et al. 2013), and 0.03% of the Eastern 
North Pacific stock of gray whale population (estimated at 19,126; 
Allen and Angliss 2013).
    Animals exposed to construction noise associated with the SF-OBB 
construction work would be limited to Level B behavioral harassment 
only, i.e., the exposure of received levels for impulse noise between 
160 and 180 dB (rms) re 1 [mu]Pa (from impact pile driving) and for 
non-impulse noise between 120 and 180 dB (rms) re 1 [mu]Pa (from 
vibratory pile driving). In addition, the potential behavioral 
responses from exposed animals are expected to be localized and short 
in duration.
    These low intensity, localized, and short-term noise exposures 
(i.e., 160 dB re 1 [mu]Pa (rms) from impulse sources and 120 dB re 1 
[mu]Pa (rms) from non-impulse sources), are expected to cause brief 
startle reactions or short-term behavioral modification by the animals. 
These brief reactions and behavioral changes are expected to disappear 
when the exposures cease. The maximum estimated 160 dB isopleths from 
impact pile driving is 500 m from the pile, and the estimated 120 dB 
maximum isopleths from vibratory pile driving is approximately 2,000 m 
from the pile. There is no pinniped haul-out area in the vicinity of 
the pile driving sites. There is no critical habitat or other 
biologically important area for marine mammals in the vicinity of the 
proposed SF-OBB construction area. Therefore, these levels of received 
underwater construction noise from the proposed SF-OBB construction 
project are not expected to affect marine mammal annual rates of 
recruitment or survival.
    For the reasons discussed in this document, NMFS has preliminarily 
determined that the impact of in-water pile driving associated with 
construction of the SF-OBB would result, at worst, in the Level B 
harassment of small numbers of California sea lions, Pacific harbor 
seals, harbor porpoises, and potentially gray whales that inhabit or 
visit SFB in general and the vicinity of the SF-OBB in particular. 
While behavioral modifications, including temporarily vacating the area 
around the construction site, may be made by these species to avoid the 
resultant visual and acoustic disturbance, the availability of 
alternate areas within SFB and haul-out sites (including pupping sites) 
and feeding areas within the Bay has led NMFS to preliminarily 
determine that this action will have a negligible impact on California 
sea lion, Pacific harbor seal, harbor porpoise, and gray whale species 
or stocks along the California coast.
    In addition, no take by Level A harassment (injury) or death is 
anticipated and harassment takes should be at the lowest level 
practicable due to incorporation of the proposed mitigation measures 
mentioned previously in this document.

Impact on Availability of Affected Species for Taking for Subsistence 
Uses

    There are no relevant subsistence uses of marine mammals implicated 
by this action.

Proposed Incidental Harassment Authorization

    This section contains a draft of the IHA itself. The wording 
contained in this section is proposed for inclusion in the IHA (if 
issued).
    (1) This Authorization is valid from January 8, 2014, through 
January 7, 2015.
    (2) This Authorization is valid only for activities involving the 
construction and dismantling of the East Span of SF-OBB, California.
    (3) Species Impacted and Level of Takes.
    (a) The species authorized for takings by incidental harassment are 
the California sea lion (Zalophus californianus), Pacific harbor seal 
(Phoca vitulina richardsi), harbor porpoise (Phocoena phocoena), and 
gray whale (Eschrichtius robustus).
    (b) The taking of any marine mammal in a manner prohibited under 
this Authorization must be reported within 24 hours of the taking to 
the Director, Southwest Regional Office, National Marine Fisheries 
Service, Telephone (562) 980-4000 and the Director, Office of Protected 
Resources, National Marine Fisheries Service, Telephone (301) 427-8400.
    (4) The holder of this Authorization is required to cooperate with 
the National Marine Fisheries Service and any other Federal, state or 
local agencies monitoring the impacts of the activity on marine 
mammals. The holder must notify Monica DeAngelis of the Southwest 
Regional Office (phone: (562) 980-3232) at least 24 hours prior to 
starting activities.
    (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 2. The taking by Level A harassment, injury, serious injury, or 
death of these species or the taking by harassment, injury, serious 
injury, or death of any other species of marine mammal is prohibited 
and may result in the modification, suspension, or revocation of this 
Authorization.
    (6) Mitigation Requirements.
    (a) Use of Noise Attenuation Devices.
    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.
    (b) Establishment and Monitoring of Exclusion and Level B 
Harassment Zones.
    (i) For all in-water pile driving and mechanical dismantling 
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 Level B 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

[[Page 60859]]

(vibratory pile driving and mechanic dismantling), respectively.
    (ii) The sizes of the initial exclusion and Level B harassment 
zones for different types of activities are provided in Table 1 above. 
Once hydroacoustic measurements of pile driving and mechanical 
dismantling activities have been conducted, CALTRANS shall revised the 
sizes of the zones based on actual measurements.
    (iii) NMFS-approved protected species observers (PSOs) shall 
conduct initial survey of the safety zone to ensure that no marine 
mammals are seen within the zones before impact pile driving and 
mechanical dismantling of bridge foundation. If marine mammals are 
found within the exclusion zones, impact pile driving and/or mechanical 
dismantling activity of the segment 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 harbor 
porpoise and 30 minutes for gray whale. 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.
    (iv) 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 observer(s) must notify the Resident Engineer (or other authorized 
individual) immediately (see condition 5(e)).
    (c) 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 full power, prior to operating pile driving 
hammers at full capacity for both impact and vibratory pile driving.
    (d) Power Down and Shut-down.
    (i) For mechanical dismantling of bridge foundation, construction 
activities that generate underwater noise must be powered down or 
shutdown if a marine mammal is observed within the established 180 dB 
or 190 dB re 1 [mu]Pa exclusion zones for cetaceans or pinnipeds, 
respectively.
    (ii) For pile driving activities, if a marine mammal is sighted 
within the exclusion zone after pile-driving has begun, CALTRANS must 
have a qualified marine mammal observer record the species, numbers and 
behaviors of the animal(s) and report to Monica DeAngelis at the 
Southwest Regional Office, National Marine Fisheries Service, (phone: 
(562) 980-3232) within 24 hours of the incident.
    (7) Monitoring Requirements.
    (a) General.
    (1) The holder of this Authorization must designate a minimum of 
three biologically-trained, on-site protected species observers (PSOs), 
approved in advance by the National Marine Fisheries Service's 
Southwest Regional Office, to monitor the area for marine mammals 
before, during, and after pile driving activities; and before, during, 
and after mechanical dismantling of marine foundations.
    (2) The National Marine Fisheries Service must be informed 
immediately of any changes or deletions to any portions of the 
monitoring plan in accordance with condition 7(a) of this 
Authorization.
    (b) Visual Monitoring.
    (i) 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, attenuated impact pile driving of pipe piles (except 
pile proofing) and mechanical dismantling for 180- and 190-dB re 1 
[mu]Pa exclusion zones.
    (ii) 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 and mechanic dismantling for the 120 dB re 1 
[mu]Pa Level B harassment zone.
    (iii) Marine mammal monitoring shall begin at least 30 minutes 
prior to the start of the activities, through the entire construction 
activities, and continue to 30 minutes after the construction 
activities.
    (iv) 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.
    (v) 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.
    (c) Hydroacoustic Measurements.
    At the beginning of pile driving and mechanical dismantling of 
bridge foundation, CALTRANS shall conduct hydroacoustic measurements to 
verify the exclusion and Level B harassment zones.
    (7) Reporting Requirements.
    (a) CALTRANS shall notify NMFS of the initial sound pressure level 
measurements for both pile driving and foundation dismantling 
activities, including the final exclusion zone and Level B harassment 
zone radii established for impact and vibratory pile driving and marine 
foundation dismantling activities, within 72 hours after completion of 
the measurements.
    (b) Monitoring reports shall be posted on the SFOBB Project's 
biological mitigation Web site (www.biomitigation.org) on a weekly 
basis if in-water construction activities are conducted. Marine mammal 
monitoring reports shall include species and numbers of marine mammals 
observed, time and location of observation and behavior of the animal. 
In addition, the reports shall include an estimate of the number and 
species of marine mammals that may have been harassed as a result of 
activities.
    (c) CALTRANS shall provide NMFS with a draft final report within 90 
days after the expiration of the IHA. This report shall detail the 
monitoring protocol, summarize the data recorded during monitoring, and 
estimate the number of marine mammals that may have been harassed due 
to pile driving and mechanical dismantling of bridge foundations. If no 
comments are received from NMFS within 30 days, the draft final report 
would be considered the final report. If comments are received, a final 
report must be submitted within 30 days after receipt of comments.
    (8) Notification of Injured or Dead Marine Mammals.
    (a) In the unanticipated event that CALTRANS' construction 
activities clearly cause the take of a marine mammal in a manner 
prohibited by this Authorization, such as an injury (Level A 
harassment), serious injury or mortality (e.g., ship-strike, gear 
interaction, and/or entanglement), CALTRANS shall immediately cease 
construction operations and immediately report the incident to the 
Supervisor of Incidental Take Program, Permits and Conservation 
Division, Office of Protected Resources, NMFS, at 301-427-8401 and/or 
by email to [email protected] and [email protected] and NMFS 
Southwest Regional Stranding

[[Page 60860]]

Coordinators ([email protected]). The report must include the 
following information:
    (i) Time, date, and location (latitude/longitude) of the incident;
    (ii) type of activity involved;
    (iii) description of the incident;
    (iv) status of all sound source use in the 24 hours preceding the 
incident;
    (v) water depth;
    (vi) environmental conditions (e.g., wind speed and direction, 
Beaufort sea state, cloud cover, and visibility);
    (vii) description of marine mammal observations in the 24 hours 
preceding preceding the incident;
    (viii) species identification or description of the animal(s) 
involved;
    (ix) the fate of the animal(s); and
    (x) 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.
    (b) 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 Supervisor of the 
Incidental Take Program, Permits and Conservation Division, Office of 
Protected Resources, NMFS, at 301-427-8401, and/or by email to 
[email protected] and [email protected] and NMFS Southwest 
Regional Stranding Coordinators ([email protected]). The report 
must include the same information identified in Condition 8(a) 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.
    (c) 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 Condition 3 
of this Authorization (e.g., previously wounded animal, carcass with 
moderate to advanced decomposition, or scavenger damage), CALTRANS 
shall report the incident to the Supervisor of the Incidental Take 
Program, Permits and Conservation Division, Office of Protected 
Resources, NMFS, at 301-427-8401, and/or by email to 
[email protected] and [email protected] and NMFS Southwest 
Regional Stranding Coordinators ([email protected]), 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. CALTRANS can continue its operations under such a 
case.
    (9) A copy of this Authorization must be in the possession of all 
contractors and marine mammal monitors operating under the authority of 
this Incidental Harassment Authorization.

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 SF-
OBB 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. 
A copy of the SEA and FONSI is available upon request (see ADDRESSES).

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.

Proposed Authorization

    NMFS proposes to issue an IHA to CALTRANS for the potential 
harassment of small numbers of harbor seals, California sea lions, 
harbor porpoises, and gray whales incidental to construction of a 
replacement bridge for the East Span of the San Francisco-Oakland Bay 
Bridge in California, provided the previously mentioned mitigation, 
monitoring, and reporting requirements are incorporated. NMFS has 
preliminarily determined that the proposed activity would result in the 
harassment of only small numbers of harbor seals, California sea lions, 
harbor porpoises, and possibly gray whales and will have no more than a 
negligible impact on these marine mammal stocks.

    Dated: September 26, 2013.
Donna S. Wieting,
Director, Office of Protected Resources, National Marine Fisheries 
Service.
[FR Doc. 2013-24079 Filed 10-1-13; 8:45 am]
BILLING CODE 3510-22-P