Small Takes of Marine Mammals Incidental to Specified Activities; Pier 36/Brannan Street Wharf Project in the San Francisco Bay, CA, 66274-66281 [2011-27739]

Agencies

• DEPARTMENT OF COMMERCE
• National Oceanic and Atmospheric Administration

[Federal Register Volume 76, Number 207 (Wednesday, October 26, 2011)]
[Notices]
[Pages 66274-66281]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2011-27739]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

RIN 0648-XA650


Small Takes of Marine Mammals Incidental to Specified Activities; 
Pier 36/Brannan Street Wharf Project in the San Francisco Bay, CA

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

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

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SUMMARY: NMFS has received a complete and adequate application from the 
United States Army Corps of Engineers, San Francisco District (USACE), 
on behalf of the Port of San Francisco (Port), for an Incidental 
Harassment Authorization (IHA) to take marine mammals, by harassment, 
incidental to pile driving during construction of the Brannan Street 
Wharf. Pursuant to the Marine Mammal Protection Act (MMPA), NMFS is 
proposing to issue an IHA to incidentally harass, by Level B 
harassment, four species of marine mammals during the specified 
activity within a specific geographic region and is requesting comments 
on its proposal.

DATES: Comments and information must be received no later than November 
25, 2011.

ADDRESSES: Comments on the application and this proposal should be 
addressed to Michael Payne, Chief, Permits, Conservation and Education 
Division, Office of Protected Resources, National Marine Fisheries 
Service, 1315 East-West Highway, Silver Spring, MD 20910-3225. The 
mailbox address for

[[Page 66275]]

providing e-mail comments is ITP.Magliocca@noaa.gov. NMFS is not 
responsible for e-mail comments sent to addresses other than the one 
provided here. Comments sent via e-mail, 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 https://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 containing a list of the references used 
in this document may be obtained by writing to the address specified 
above, telephoning the contact listed below (see FOR FURTHER 
INFORMATION CONTACT), or visiting the internet at: https://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: Michelle Magliocca, 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 United States citizens who engage in a specified activity 
(other than commercial fishing) within a specific geographical region 
if certain findings are made and either regulations are issued or, if 
the taking is limited to harassment, a notice of a proposed 
authorization is provided to the public for review.
    Authorization for incidental takings shall be granted if NMFS finds 
that the taking will have a negligible impact on the species or 
stock(s), will not have an unmitigable adverse impact on the 
availability of the species or stock(s) for subsistence uses (where 
relevant), and if the permissible methods of taking and requirements 
pertaining to the mitigation, monitoring and reporting of such takings 
are set forth. NMFS has defined ``negligible impact'' in 50 CFR 216.103 
as `` * * * an impact resulting from the specified activity that cannot 
be reasonably expected to, and is not reasonably likely to, adversely 
affect the species or stock through effects on annual rates of 
recruitment or survival.''
    Section 101(a)(5)(D) of the MMPA established an expedited process 
by which citizens of the United States can apply for an authorization 
to incidentally take small numbers of marine mammals by harassment. 
Section 101(a)(5)(D) further established a 45-day time limit for NMFS' 
review of an application, followed by a 30-day public notice and 
comment period on any proposed authorizations for the incidental 
harassment of marine mammals. Within 45 days of the close of the 
comment period, NMFS must either issue or deny the authorization.
    Except with respect to certain activities not pertinent here, the 
MMPA defines ``harassment'' as:

any act of pursuit, torment, or annoyance which (i) has the 
potential to injure a marine mammal or marine mammal stock in the 
wild [Level A harassment]; or (ii) has the potential to disturb a 
marine mammal or marine mammal stock in the wild by causing 
disruption of behavioral patterns, including, but not limited to, 
migration, breathing, nursing, breeding, feeding, or sheltering 
[Level B harassment].

Summary of Request

    On May 6, 2011, NMFS received an application from the USACE, on 
behalf of the Port, requesting an IHA for the take, by Level B 
harassment, of small numbers of Pacific harbor seals (Phoca vitulina), 
California sea lions (Zalophus californianus), gray whales 
(Eschrichtius robustus), and Pacific harbor porpoises (Phocoena 
phocoena) incidental to pile driving activities during construction of 
the Brannan Street Wharf in San Francisco, California. Upon receipt of 
additional information and a revised application, NMFS determined the 
application complete and adequate on August 7, 2011.
    The Port proposes to construct a pile-supported park that would be 
known as the ``Brannan Street Wharf'' and would replace the existing 
Pier 36 and provide recreational space for the public. The proposed 
project would require installation of 261 steel and concrete piles and 
57,000 square feet (ft\2\) of new decking. Because elevated sound 
levels from pile driving have the potential to result in marine mammal 
harassment, NMFS is proposing to issue an IHA for take incidental to 
the specified activity.

Description of the Specified Activity

    The Port proposes to replace the existing Pier 36 with a pile-
supported park along the San Francisco waterfront. The proposed park 
would provide a new open space for the purpose of public recreation and 
include the following: a 26,000 ft\2\ raised lawn area; a waterside 
walkway with seating, shelters, and picnic tables; and a 2,000 ft\2\ 
small craft float and accessible gangway for launching non-motorized 
recreational vessels.
    To construct the 57,000 ft\2\ open space, the existing overwater 
Pier 36 structures would be demolished, the existing supporting 
caissons would be removed, and 261 steel and concrete piles would be 
installed at the site using vibratory and impact pile driving. 
Demolition and removal of the caissons is not expected to harass marine 
mammals because these activities would occur above water and the height 
of the existing Pier 36 decking prevents marine mammals from hauling 
out. (The nearest haul-out site is over 3.2 kilometers (km) (2 miles 
[mi]) away at Yerba Buena Island.) The caissons would be removed using 
a barge mounted excavator and this method is not expected to generate 
sound at pressures outside of the ambient noise conditions. 
Installation of the new cast-in-place concrete decking would also occur 
above water. Installation of the 261 steel and concrete piles, however, 
would require in-water pile driving that could produce high-intensity 
sound and has the potential to harass marine mammals. A breakdown of 
proposed pile size and type is shown in Table 1.

                            Table 1--Summary of Pile Types and Pile Driving Activity
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                                                                                                  Max piles per
                  Pile type                      Total piles              Pile driver                  day
----------------------------------------------------------------------------------------------------------------
24-inch octagonal concrete..................               141  Impact........................                 8
24-inch steel shell.........................               116  Vibratory and impact..........                 5
36-inch steel shell.........................                 4  Vibratory and impact..........                 4
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[[Page 66276]]

    Of the 261 piles, about 141 would be 24-inch (in) octagonal 
concrete piles driven in water depths of 2 to 15 ft mean lower low 
water. These piles would be driven to a depth of 60 ft below the 
mudline elevation--like all the other piles--using an impact hammer. 
Each pile may take 20 minutes to drive into the substrate, which 
consists of about 20 ft of bay mud underlain by a sand mixture. Up to 
800 blows from an impact hammer would be necessary for each concrete 
pile.
    Of the 261 piles, about 116 would be 24-in steel shell piles driven 
in water depths of zero to 6 ft mean lower low water. These piles would 
be installed nearest the shoreline as pier support piles and would be 
used in place of concrete piles due to the presence of rock dike 
material along the shore. Installation would include about eight 
minutes of vibratory pile driving, followed by up to 300 blows from an 
impact hammer.
    The remaining 4 piles would be 36-in steel shell piles used for the 
new floating dock. These piles would be installed in water depths of 10 
to 15 ft mean lower low water. Each pile installation would begin with 
five to 15 minutes of vibratory pile driving, followed by about 600 
blows from an impact hammer.
    Only one pile type is expected to be installed on any given day. 
Conservatively assuming the maximum vibratory time and number of impact 
blows required for each pile, a total of 988 minutes of vibratory 
driving and 150,000 impact blows would be necessary over the 12-month 
duration of the project. All vibratory pile driving would use a 
standard frequency hammer similar to an APE 150, which produces up to 
1,800 vibrations per minute. All impact pile driving would use a DelMag 
D46-32 diesel impact hammer, which produces about 122,000 foot-pounds 
maximum energy blow at 1.5 seconds per blow on average. A bubble 
curtain would be used as a sound attenuation device during impact pile 
driving for the 24-in and 36-in steel shell piles.

Region of Activity

    The proposed activity would occur in the San Francisco Bay at Pier 
36, four blocks south of the San Francisco Oakland Bay Bridge. More 
specifically, this area is located between Pier 30-32 and Pier 38, 
directly adjacent to the east side of the Embarcadero and within the 
South of Market district of San Francisco. San Francisco Bay and the 
adjacent Sacramento-San Joaquin Delta make up one of the largest 
estuarine systems on the continent. The Bay has undergone extensive 
industrialization, but remains an important environment for healthy 
marine mammal populations year round. The area surrounding the proposed 
activity is an intertidal landscape with heavy industrial use and boat 
traffic.

Dates of Activity

    Wharf and pier demolition--which is not expected to harass marine 
mammals--may begin in January 2012 and last for five months. The new 
wharf construction, including pile driving, is scheduled to begin in 
May 2012 and end 13 months later; however, pile driving is expected to 
be complete by December 2012.

Sound Propagation

    For background, sound is a mechanical disturbance consisting of 
minute vibrations that travel through a medium, such as air or water, 
and is generally characterized by several variables. Frequency 
describes the sound's pitch and is measured in hertz (Hz) or kilohertz 
(kHz), while sound level describes the sound's loudness and is measured 
in decibels (dB). Sound level increases or decreases exponentially with 
each dB of change. For example, 10 dB yields a sound level 10 times 
more intense than 1 dB, while a 20 dB level equates to 100 times more 
intense, and a 30 dB level is 1,000 times more intense. Sound levels 
are compared to a reference sound pressure (micro-Pascal) to identify 
the medium. For air and water, these reference pressures are ``re: 20 
[micro]Pa'' and ``re: 1 [micro]Pa,'' respectively. Root mean square 
(RMS) is the quadratic mean sound pressure over the duration of an 
impulse. RMS is calculated by squaring all of the sound amplitudes, 
averaging the squares, and then taking the square root of the average 
(Urick, 1975). RMS accounts for both positive and negative values; 
squaring the pressures makes all values positive so that they may be 
accounted for in the summation of pressure levels (Hastings and Popper, 
2005). This measurement is often used in the context of discussing 
behavioral effects, in part because behavioral effects, which often 
result from auditory cues, may be better expressed through averaged 
units rather than by peak pressures.
    A review of numerous pile driving projects with comparable water 
depth and substrate conditions was conducted to identify source sound 
level data and estimate potential sound levels for pile driving 
activities around Pier 36. In their calculations, the Port 
conservatively assumed that the use of a bubble curtain for steel shell 
piles would reduce sound levels by 5 dB RMS. A conservative attenuation 
factor of 16 dB RMS (about 5 dB RMS per doubling of distance) was also 
assumed in the Port's analysis; sound attenuation would likely be 
greater than 16 dB RMS for such shallow water pile driving (CalTrans, 
2009). Pile driving at Pier 36 is expected to occur in water depths of 
zero to 15 feet. Maximum sound pressure levels for pile driving 
activities are shown in Table 2.

    Table 2--Measured Unattenuated Sound Pressure Levels in the Near Field (10 m) During Pile Driving in San
                                         Francisco Bay (Caltrans, 2009)
----------------------------------------------------------------------------------------------------------------
              Pile type                  Attenuation device      Sound level (impact)    Sound level (vibratory)
----------------------------------------------------------------------------------------------------------------
24-in octagonal concrete............  None...................  170 dB                    n/a
24-in steel shell...................  Bubble curtain.........  190 dB                    165 dB
36-in steel shell...................  Bubble curtain.........  190 dB                    175 dB
----------------------------------------------------------------------------------------------------------------

Description of Marine Mammals in the Area of the Specified Activity

    Marine mammals with confirmed occurrences in San Francisco Bay are 
the Pacific harbor seal, California sea lion, gray whale, harbor 
porpoise, humpback whale (Megaptera noveangliae), and sea otter 
(Enhydra lutris). However, humpback whales are considered extremely 
rare in San Francisco Bay and are highly unlikely to be present in the 
project vicinity during pile driving. Sea otters are managed by the 
United States Fish and Wildlife Service. Therefore, these two species 
are not discussed further.

[[Page 66277]]

Pacific Harbor Seals

    Pacific harbor seals reside in coastal and estuarine waters off 
Baja, California, north to British Columbia, west through the Gulf of 
Alaska, and in the Bering Sea. The most recent harbor seal counts 
estimate the California stock of Pacific harbor seals at 34,233 
individuals. The population appears to be stabilizing at what may be 
their carrying capacity, and human-caused mortality is declining (NMFS, 
2005). The California stock of Pacific harbor seals is not listed under 
the Endangered Species Act (ESA) nor considered depleted under the 
MMPA.
    In California, approximately 400-500 harbor seal haul-out sites are 
widely distributed along the mainland and offshore islands, including 
intertidal sandbars, rocky shores, and beaches. The northside of Yerba 
Buena Island is the closest haul-out to the project location, 
approximately 3.2 km (2 mi) from Pier 36. Although harbor seals use 
this haul-out year-round, Yerba Buena Island is not considered a 
pupping site. In California, breeding occurs from March to May, and 
pupping between April and May depending on local populations. Harbor 
seals around Pier 36 would likely be transiting to and from their 
closest haul-out (Yerba Buena Island) or opportunistically foraging. 
Herring spawning events could result in harbor seals congregating and 
approaching the action area sporadically in an unpredictable manner 
(pers. comm., M. DeAngelis to M. Magliocca).
    Pinnipeds produce a wide range of social signals, most occurring at 
relatively low frequencies (Southall et al., 2007), suggesting that 
hearing is keenest at these frequencies. Pinnipeds communicate 
acoustically both on land and underwater, but have different hearing 
capabilities dependent upon the medium (air or water). Based on 
numerous studies, as summarized in Southall et al. (2007), pinnipeds 
are more sensitive to a broader range of sound frequencies underwater 
than in air. Underwater, pinnipeds can hear frequencies from 75 Hz to 
75 kHz. In air, pinnipeds can hear frequencies from 75 Hz to 30 kHz 
(Southall et al., 2007).

California Sea Lions

    California sea lions reside throughout the Eastern North Pacific 
Ocean in shallow coastal and estuarine waters, ranging from Central 
Mexico to British Columbia, Canada. Their primary breeding range 
extends from Central Mexico to the Channel Islands in Southern 
California. The United States stock abundance is estimated at 238,000 
sea lions (NMFS, 2007). This stock is approaching carrying capacity and 
is reaching ``optimum sustainable population'' limits, as defined by 
the MMPA. California sea lions are not listed under the ESA nor 
considered depleted under the MMPA.
    Sandy beaches are preferred habitat for haul-out sites, but marina 
docks, jetties, and buoys are often used in California for resting, 
breeding, and molting. In San Francisco Bay, sea lions have been 
observed at Angel Island and are known to haul out on buoys and 
floating docks near Pier 39, which is about 3.6 km (2.2 mi) north of 
the proposed project site. Sea lions usually appear at Pier 39 after 
returning from the Channel Islands at the beginning of August. No other 
sea lion haul-out sites have been identified in the Bay and no pupping 
has been observed in the Bay. Sea lions observed within this area may 
be transiting to and from nearby piers or opportunistically foraging.
    Pinnipeds produce a wide range of social signals, most occurring at 
relatively low frequencies (Southall et al., 2007), suggesting that 
hearing is keenest at these frequencies. Pinnipeds communicate 
acoustically both on land and underwater, but have different hearing 
capabilities dependent upon the medium (air or water). Based on 
numerous studies, as summarized in Southall et al. (2007), pinnipeds 
are more sensitive to a broader range of sound frequencies underwater 
than in air. Underwater, pinnipeds can hear frequencies from 75 Hz to 
75 kHz. In air, pinnipeds can hear frequencies from 75 Hz to 30 kHz 
(Southall et al., 2007).

Harbor Porpoises

    Harbor porpoises have a wide and discontinuous range that includes 
the North Atlantic and North Pacific. In the Eastern North Pacific, 
harbor porpoises are found in coastal and inland waters from Point 
Conception, California to Alaska. Harbor porpoises in United States 
waters are divided into 10 stocks, based on genetics, movement 
patterns, and management. Any harbor porpoises encountered during the 
proposed project would likely be part of the San Francisco-Russian 
River stock, which has an estimated abundance of 9,189 animals. This 
stock appeared to be stable or declining between 1988 and 1991 and has 
steadily increased since 1993, although not significantly. Harbor 
porpoises are not commonly sighted in San Francisco Bay, but have been 
observed traveling in small pods of two to three animals on occasion 
(pers. comm., M. DeAngelis to M. Magliocca) and sightings have been 
reported by the California Department of Transportation. The closest 
sightings to Pier 36 have been near Yerba Buena Island, about 3.2 km (2 
mi) away. They may occur in the action area during a time when they 
could be affected by pile driving activities; however, their presence 
in the vicinity is rare. Harbor porpoises in California are not listed 
under the ESA nor considered depleted under the MMPA.
    Cetaceans are divided into three functional hearing groups: low-
frequency, mid-frequency, and high-frequency. Harbor porpoises are 
considered high-frequency cetaceans and their estimated auditory 
bandwidth (lower to upper frequency hearing cut-off) ranges from 200 Hz 
to 180 kHz.

Gray Whales

    Gray whales are large mysticetes, or baleen whales, found mainly in 
shallow coastal waters of the North Pacific Ocean. Two isolated 
geographic distributions of gray whales exist: the Eastern North 
Pacific stock and the Western North Pacific stock. The Eastern North 
Pacific stock migrates as far south as Baja, California for breeding 
and calving in the winter and as far north as the Bering and Chukchi 
Seas for summer feeding. During migration, gray whales occasionally 
enter rivers and bays in very low numbers. They could potentially be in 
the proposed project area during pile driving activities. The most 
recent 2008 stock assessment report estimated the Eastern North Pacific 
stock to be approximately 18,813 individuals with an increasing 
population trend over the past several decades. Gray whales were 
delisted from the ESA in 1994 and are not considered depleted under the 
MMPA.
    Gray whales, like other baleen whales, are in the low-frequency 
hearing group. There are no empirical data on gray whale hearing; 
however, Wartzok and Ketten (1999) suggest that mysticete hearing is 
most sensitive at the same frequencies at which they vocalize. 
Underwater sounds produced by gray whales range from 20 Hz to 20 kHz 
(Richardson et al., 1995).

Potential Effects on Marine Mammals

    The proposed action consists of both in-water and above-water 
components, but the only activity with the potential to take marine 
mammals is pile driving. Elevated in-water sound levels from pile 
driving in the proposed project area may temporarily impact marine 
mammal behavior. Elevated in-air sound levels are not a concern because 
the nearest pinniped haul-out is approximately 3.2 km (2 mi) away. 
Marine mammals are continually exposed to many sources of sound. For 
example, lightning, rain, sub-sea earthquakes, and animals are

[[Page 66278]]

natural sound sources throughout the marine environment. Marine mammals 
produce sounds in various contexts and use sound for various biological 
functions including, but not limited to, (1) Social interactions; (2) 
foraging; (3) orientation; and (4) predator detection. Interference 
with producing or receiving these sounds may result in adverse impacts. 
Audible distance or received levels will depend on the sound source, 
ambient noise, and the sensitivity of the receptor (Richardson et al., 
1995). Marine mammal reactions to sound may depend on sound frequency, 
ambient sound, what the animal is doing, and the animal's distance from 
the sound source (Southall et al., 2007).

Hearing Impairment

    Marine mammals may experience temporary or permanent hearing 
impairment when exposed to loud sounds. Hearing impairment is 
classified by temporary threshold shift (TTS) and permanent threshold 
shift (PTS). There are no empirical data for when PTS first occurs in 
marine mammals; therefore, it must be estimated from when TTS first 
occurs and from the rate of TTS growth with increasing exposure levels. 
PTS is likely if the animal's hearing threshold is reduced by >=40 dB 
of TTS. PTS is considered auditory injury (Southall et al., 2007) and 
occurs in a specific frequency range and amount. Irreparable damage to 
the inner or outer cochlear hair cells may cause PTS; however, other 
mechanisms are also involved, such as exceeding the elastic limits of 
certain tissues and membranes in the middle and inner ears and 
resultant changes in the chemical composition of the inner ear fluids 
(Southall et al., 2007). Due to proposed mitigation measures and source 
levels in the proposed project area, NMFS does not expect marine 
mammals to be exposed to PTS levels.

Temporary Threshold Shift (TTS)

    TTS is the mildest form of hearing impairment that can occur during 
exposure to a loud sound (Kryter, 1985). While experiencing TTS, the 
hearing threshold rises and a sound must be louder in order to be 
heard. TTS can last from minutes or hours to days, occurs 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 
occur to varying degrees (e.g., an animal's hearing sensitivity might 
be reduced by 6 dB or by 30 dB). For sound exposures at or somewhat 
above the TTS-onset threshold, hearing sensitivity recovers rapidly 
after exposure to the sound ends. Few data on sound levels and 
durations necessary to elicit mild TTS have been obtained for marine 
mammals. Southall et al. (2007) considers a 6 dB TTS (i.e., baseline 
thresholds are elevated by 6 dB) sufficient to be recognized as an 
unequivocal deviation and thus a sufficient definition of TTS-onset. 
Because it is non-injurious, NMFS considers TTS as Level B harassment 
that is mediated by physiological effects on the auditory system; 
however, NMFS does not consider onset TTS to be the lowest level at 
which Level B harassment may occur.
    Southall et al. (2007) summarizes underwater pinniped data from 
Kastak et al. (2005), indicating that a tested harbor seal showed a TTS 
of around 6 dB when exposed to a non-pulse noise at SPL 152 dB re: 1 
[mu]Pa for 25 minutes. In contrast, a tested sea lion exhibited TTS-
onset at 174 dB re: 1 [mu]Pa under the same conditions as the harbor 
seal. Data from a single study on underwater pulses found no signs of 
TTS-onset in sea lions at exposures up to 183 dB re: 1 [mu]Pa (peak-to-
peak) (Finneran et al., 2003). There is no information on species-
specific TTS for harbor porpoises or gray whales.

Behavioral Effects

    There are limited data available on the behavioral effects of non-
pulse noise (for example, vibratory pile driving) on pinnipeds while 
underwater; however, field and captive studies to date collectively 
suggest that pinnipeds do not react strongly to exposures between 90 
and 140 dB re: 1 microPa; no data exist from exposures at higher 
levels. Jacobs and Terhune (2002) observed wild harbor seal reactions 
to high-frequency acoustic harassment devices around nine sites. Seals 
came within 44 m of the active acoustic harassment devices and failed 
to demonstrate any behavioral response when received SPLs were 
estimated at 120-130 dB. In a captive study (Kastelein, 2006), 
scientists subjected a group of seals to non-pulse sounds between 8 and 
16 kHz. Exposures between 80 and 107 dB did not induce strong 
behavioral responses; however, a single observation from 100 to 110 dB 
indicated an avoidance response. The seals returned to baseline 
conditions shortly following exposure. Southall et al. (2007) notes 
contextual differences between these two studies; the captive animals 
were not reinforced with food for remaining in the noise fields, 
whereas free-ranging animals may have been more tolerant of exposures 
because of motivation to return to a safe location or approach 
enclosures holding prey items. Vibratory and impact pile driving may 
result in anticipated hydroacoustic levels between 165 and 190 dB root 
mean square. Southall et al. (2007) reviewed relevant data from studies 
involving pinnipeds exposed to pulse sounds and concluded that 
exposures to 150 to 180 dB generally have limited potential to induce 
avoidance behavior.
    No known data exist for sound levels resulting from the type of 
vibratory hammer and pile sizes that would be used at the proposed 
project site; however, measured sound levels for the ``King Kong'' 
vibratory hammer used in Richmond, California ranged between 163 and 
180 dB RMS (Illingworth and Rodkin, 2007). Sound levels at the proposed 
project site are expected to be lower because the vibratory hammer 
being used has an expected sound level of 165 dB for 24-in piles and 
175 dB for 36-in piles. In addition, San Francisco Bay is highly 
industrialized and masking of the pile driver by other vessels and 
anthropogenic noise within the action area may, especially in the 
nearby shipping channel, make construction sounds difficult to hear at 
greater distances. Underwater ambient noise levels along the San 
Francisco waterfront may be around 133 dB RMS, based on measurements 
from the nearby Oakland Outer Harbor (Caltrans, 2009). Seals would 
likely also exhibit tolerance or habituation (Richardson et al., 1999) 
due to the amount of anthropogenic noise within the proposed project 
area and San Francisco Bay as a whole.
    No impacts to marine mammal reproduction are anticipated because 
there are no known pinniped haul-outs or rookeries within the proposed 
project area and San Francisco Bay is not a known breeding ground for 
cetaceans. Marine mammals may avoid the area around the hammer, thereby 
reducing their exposure to elevated sound levels. NMFS expects any 
impacts to marine mammal behavior to be temporary, Level B harassment 
(for example, avoidance or alteration of behavior). The Port 
conservatively assumes that five 24-in concrete piles would be 
installed per day, three 24-in steel piles would be installed per day, 
and four 36-in steel piles would be installed per day. Considering that 
only one pile type is expected to be installed on any given day, the 
maximum number of pile driving days is expected to be 69 over the 
eight-month period. Marine mammal injury or mortality is not likely, as 
the 180 dB isopleth (NMFS' Level A harassment threshold for cetaceans) 
for the impact hammer is 42 m (138 ft) and would be continuously 
monitored for marine mammals. Impact pile driving would

[[Page 66279]]

cease if a marine mammal is observed nearing or within a Level A 
harassment exclusion zone (50 m [164 ft]). For these reasons, NMFS 
expects any changes to marine mammal behavior to be temporary.

Anticipated Effects on Habitat

    No permanent detrimental impacts to marine mammal habitat are 
expected to result from the proposed project. Pile driving (resulting 
in temporary ensonification) may impact prey species and marine mammals 
by resulting in avoidance or abandonment of the area; however, these 
impacts are expected to be local and temporary. Site conditions are 
expected to be improved or substantively unchanged from existing 
conditions. The proposed project would result in the net removal of 
approximately 3,550 ft\2\ of pile fill and clearing of 47,000 ft\2\ of 
timber debris that has collapsed at the end of Pier 36. This debris 
includes 350-400 creosote-treated wood pilings. Creosote can leach out 
of the wood over time, potentially causing long-term impacts to marine 
species. The proposed project would also result in a net reduction of 
47,000 ft\2\ of shadow fill (shading over the water). This increase of 
unshaded water is expected to be beneficial to benthic invertebrates, 
fish, and marine mammals through restoration of ambient light 
conditions and increased biological productivity. Overall, the proposed 
activity is not expected to cause significant or long-term adverse 
impacts on marine mammal habitat.

Proposed Mitigation

    In order to issue an IHA under section 101(a)(5)(D) of the MMPA, 
NMFS must set forth the permissible methods of taking pursuant to such 
activity, and other means of effecting the least practicable 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.
    The Port proposed the following mitigation measures to minimize 
adverse impacts to marine mammals:

Sound Attenuation Device

    When using impact pile driving to install steel piles in water 
depths greater than two feet, an unconfined bubble curtain would be 
used to reduce hydroacoustic sound levels to avoid the potential for 
injury. The bubble curtain is expected to reduce sound levels by at 
least 5 dB.

Establishment of an Exclusion Zone

    During all in-water impact pile driving, the Port would establish a 
preliminary marine mammal exclusion zone with 50 m (164 ft) radius 
around each pile to avoid exposure to sounds at or above 180 dB. This 
includes an 8-m (26-ft) buffer zone to further avoid marine mammals 
from entering the 180 dB isopleth. The exclusion zone would be 
monitored during all impact pile driving to ensure that no marine 
mammals enter the 50-m (164-ft) radius. The purpose of this area is to 
prevent Level A harassment (injury) of any marine mammal species. Once 
underwater sound measurements are taken, the exclusion zone may be 
adjusted accordingly so that marine mammals are not exposed to Level A 
harassment sound pressure levels. A safety zone for vibratory pile 
driving or installation of concrete piles is unnecessary as source 
levels would not exceed the Level A harassment threshold.

Pile Driving Shut Down and Delay Procedures

    If a protected species observer sees a marine mammal within or 
approaching the exclusion zone prior to start of impact pile driving, 
the observer would notify the on-site resident engineer (or other 
authorized individual) who would then be required to delay pile driving 
until the marine mammal has moved outside of the exclusion zone or if 
the animal has not been resighted within 15 minutes for pinnipeds or 30 
minutes for cetaceans. If a marine mammal is sighted within or on a 
path toward the exclusion zone during pile driving, pile driving should 
cease until that animal has cleared and is on a path away from the 
exclusion zone or 15/30 minutes (pinnipeds/cetaceans) has lapsed since 
the last sighting.

Soft-Start Procedures

    A ``soft-start'' technique would be used at the beginning of each 
pile installation to allow any marine mammal that may be in the 
immediate area to leave before the pile hammer reaches full energy. For 
vibratory pile driving, the soft-start procedure requires contractors 
to initiate noise from the vibratory hammer for 15 seconds at 40-60 
percent reduced energy followed by a 1-minute waiting period. The 
procedure would be repeated two additional times before full energy may 
be achieved. For impact hammering, contractors would be required to 
provide an initial set of three strikes from the impact hammer at 40 
percent energy, followed by a 1-minute waiting period, then two 
subsequent three-strike sets. Soft-start procedures would be conducted 
prior to driving each pile if hammering ceases for more than 30 
minutes.

Monitoring for Herring

    Monitoring for herring spawning events would be conducted on a 
daily basis between December 1 and February (although pile driving is 
expected to be complete in December). If a herring spawning event is 
observed, in-water work would cease for a period of two weeks following 
the spawning event (a measure designed to reduce impacts to fish). 
Pinniped presence can be sporadic and unpredictable during herring runs 
in San Francisco Bay; therefore, this mitigation measure would minimize 
impacts to marine mammals.
    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 adverse impact on the affected marine mammal species and 
stocks and their habitat. Our evaluation of potential measures included 
consideration of the following factors in relation to one another: (1) 
The manner in which, and the degree to which, the successful 
implementation of the measure is expected to minimize adverse impacts 
to marine mammals; (2) the proven or likely efficacy of the specific 
measure to minimize adverse impacts as planned; and (3) the 
practicability of the measure for applicant implementation, including 
consideration of personnel safety, and practicality of implementation.
    Based on our evaluation of the applicant's proposed measures, NMFS 
has preliminarily determined that the proposed mitigation measures 
provide the means of effecting the least practicable adverse impacts 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 IHA for an activity, section 101(a)(5)(D) of 
the MMPA states that NMFS must set forth ``requirements pertaining to 
the monitoring and reporting of such taking.'' The MMPA implementing 
regulations at 50 CFR 216.104 (a)(13) indicate that requests for IHAs 
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

[[Page 66280]]

populations of marine mammals that are expected to be present.
    Hydroacoustic monitoring would be performed at the initial 
installation of each pile type (24-in concrete, 24-in steel, and 36-in 
steel) to ensure that the harassment isopleths are not extending past 
the calculated distances described in this notice. The Port must 
designate at least one biologically-trained, on-site individual, 
approved in advance by NMFS, to monitor the Level B harassment zone 
area for marine mammals 30 minutes before, during, and 30 minutes after 
all impact pile driving activities and call for shut down if any marine 
mammal is observed within or approaching the designated exclusion zone 
(preliminarily set at 50 m [164 ft]). In addition, at least two NMFS-
approved protected species observers would conduct behavioral 
monitoring out to 1,900 m during all vibratory pile driving for the 
first two weeks of activity to validate take estimates and evaluate the 
behavioral impacts piles driving has on marine mammals out to the Level 
B harassment isopleth. If there are no observations of marine mammals 
within the Level B harassment isopleth during this time, behavioral 
monitoring may be reduced to a level agreed upon by the applicant and 
NMFS. Note that for impact hammering, the initial Level B (160 dB) 
harassment isopleths are 42 m (138 ft) for the concrete piles and 750 m 
(2,460 ft) for the steel piles. For vibratory hammering, the initial 
estimated distance is 1,900 m (6,233 ft). If light condition is low 
(such as early morning or late afternoon), protected species observers 
would use infrared scopes to conduct their observations.
    Protected species observers would be provided with the equipment 
necessary to effectively monitor for marine mammals (for example, high-
quality binoculars, spotting scopes, compass, and range-finder) in 
order to determine if animals have entered into the exclusion zone or 
Level B harassment isopleth and to record species, behaviors, and 
responses to pile driving. If hydroacoustic monitoring indicates that 
threshold isopleths are greater than originally calculated, the Port 
would contact NMFS within 48 hours and make the necessary adjustments. 
Likewise, if threshold isopleths are actually less than originally 
calculated, adjustments may be made. Protected species observers would 
be required to submit a report to NMFS within 90 days of completion of 
pile driving. The report would include data from marine mammal 
sightings (such as species, group size, and behavior), any observed 
reactions to construction, distance to operating pile hammer, and 
construction activities occurring at time of sighting.

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].

    Based on the application and subsequent analysis, the impact of the 
described pile driving operations may result in, at most, short-term 
modification of behavior by small numbers of marine mammals within the 
action area. Marine mammals may avoid the area or temporarily alter 
their behavior at time of exposure.
    Current NMFS practice regarding exposure of marine mammals to 
anthropogenic noise is that in order to avoid the potential for injury 
(PTS), cetaceans and pinnipeds should not be exposed to impulsive 
sounds of 180 and 190 dB or above, respectively. This level is 
considered precautionary as it is likely that more intense sounds would 
be required before injury would actually occur (Southall et al., 2007). 
Potential for behavioral harassment (Level B) is considered to have 
occurred when marine mammals are exposed to sounds at or above 160 dB 
for impulse sounds (such as impact pile driving) and 120 dB for non-
pulse noise (such as vibratory pile driving). These levels are also 
considered precautionary.
    Distances to NMFS' harassment thresholds were calculated based on 
the sound levels at each source and the expected attenuation rate of 
sound (Table 3). Two sets of threshold distances were identified: one 
for concrete piles and one for steel piles. The threshold distances 
listed for the steel piles are those expected from the 36-in steel pile 
driving activities, as they would also encompass the isopleths for the 
24-in steel piles. The 42-m (268-ft) distance to the Level A harassment 
threshold provides protected species observers plenty of time and 
adequate visibility to prevent marine mammals from entering the area 
during impact pile driving. This would prevent marine mammals from 
being exposed to sound levels that reach the Level A harassment 
threshold. In-air sound from pile driving also has the potential to 
affect marine mammals. However, in-air sound is not a concern here 
because there are no pinniped haul-outs near the project area.

           Table 3--Calculated Underwater Distances to NMFS' Marine Mammal Harassment Threshold Levels
----------------------------------------------------------------------------------------------------------------
                                    Distance from source (24-in concrete     Distance from source (36-in steel
            Threshold                              piles)                                  piles)
----------------------------------------------------------------------------------------------------------------
120 dB RMS (Level B--continuous).  n/a...................................  1,900 m (6,233 ft).
160 dB RMS (Level B--impulse)....  42 m (138 ft).........................  750 m (2,460 ft).
180/190 dB RMS (Level A).........  n/a...................................  42 m (138 ft).
----------------------------------------------------------------------------------------------------------------

    The estimated number of marine mammals potentially taken is based 
on marine mammal monitoring reports prepared by the California 
Department of Transportation during similar activities in San Francisco 
Bay and on discussions with the NMFS Southwest Regional Office. The 
California Department of Transportation's San Francisco-Oakland Bay 
Bridge marine mammal monitoring reports were used to estimate the 
number of pinnipeds near the Pier 36/Brannan Street Wharf area as both 
sites are relatively close in distance and are similar in bathymetric 
features. However, monitoring conducted for the San Francisco-Oakland 
Bay Bridge project was in close proximity to a haul-out area, while the 
Pier 36/Brannan Street Wharf location is in an area of high commercial 
boat activity and no adjacent haul-outs. Therefore, the Caltrans data 
likely overestimate marine mammal abundance for the Pier 36/Brannan 
Street Wharf location. Based on consultation with the NMFS Southwest 
Regional Office, review of the monitoring reports described above, and 
the estimated number of pile driving

[[Page 66281]]

days, the Port requested authorization for the incidental take of 138 
harbor seals (an average of 2 per day), 69 California sea lions (an 
average of 1 per day), 69 harbor porpoises (an average of 1 per day), 
and 2 gray whales (2 annually). Based on further consultation with the 
NMFS Southwest Regional Office and previous authorizations in this 
region, NMFS is proposing to authorize the take of five gray whales 
annually, rather than two. These numbers indicate the maximum number of 
animals expected to occur within the largest Level B harassment 
isopleth (1,900 m).
Negligible Impact and Small Numbers Analysis and Determination
    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 number of factors which include, but are not limited 
to, number of anticipated injuries or mortalities (none of which would 
be authorized here), number, nature, intensity, and duration of Level B 
harassment, and the context in which takes occur.
    As described above, marine mammals would not be exposed to 
activities or sound levels which would result in injury (PTS), serious 
injury, or mortality. Pile driving would occur in shallow coastal 
waters of the Columbia River. The action area (waters around Terminal 
5) is not considered significant habitat for pinnipeds. The closest 
haul-out is 3.2 km (2 mi) away, which is well outside the project 
area's largest harassment zone. Marine mammals approaching the action 
area would likely be traveling or opportunistically foraging. The 
amount of take the Port has requested, and NMFS proposes to authorize, 
is considered small (less than one percent) relative to the estimated 
populations of 34,233 Pacific harbor seals, 238,000 California sea 
lions, 9,189 harbor porpoises, and 18,813 gray whales. Marine mammals 
may be temporarily impacted by pile driving noise. However, marine 
mammals are expected to avoid the area, thereby reducing exposure and 
impacts. Pile driving activities are expected to occur for 
approximately 69 days. Furthermore, San Francisco Bay is a highly 
industrialized area, so animals are likely tolerant or habituated to 
anthropogenic disturbance, including low level vibratory pile driving 
operations, and noise from other anthropogenic sources (such as 
vessels) may mask construction related sounds. There is no anticipated 
effect on annual rates of recruitment or survival of affected 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 determines that the Port's proposed pile 
driving activities will result in the incidental take of small numbers 
of marine mammals, by Level B harassment only, and that the total 
taking from will have a negligible impact on the affected species or 
stocks.

Impact on Availability of Affected Species for Taking for Subsistence 
Uses

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

Endangered Species Act (ESA)

    No marine mammal species listed under the ESA are anticipated to 
occur within the action area. Therefore, section 7 consultation under 
the ESA is not required.

National Environmental Policy Act (NEPA)

    In compliance with the National Environmental Policy Act of 1969 
(42 U.S.C. 4321 et seq.), as implemented by the regulations published 
by the Council on Environmental Quality (40 CFR parts 1500-1508), and 
NOAA Administrative Order 216-6, NMFS is preparing an Environmental 
Assessment (EA) to consider the direct, indirect, and cumulative 
effects to marine mammals and other applicable environmental resources 
resulting from issuance of a one-year IHA and the potential issuance of 
future authorizations for incidental harassment for the ongoing 
project. Upon completion, this EA will be available on the NMFS Web 
site listed in the beginning of this document (see ADDRESSES).

    Dated: October 19, 2011.
Helen M. Golde,
Deputy Director, Office of Protected Resources, National Marine 
Fisheries Service.
[FR Doc. 2011-27739 Filed 10-25-11; 8:45 am]
BILLING CODE 3510-22-P