Agency Information Collection Activities; Proposals, Submissions, and Approvals: Exploratorium Relocation Project in San Francisco, CA, 42691-42698 [2010-18002]
Agencies
[Federal Register: July 22, 2010 (Volume 75, Number 140)]
[Notices]
[Page 42691-42698]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr22jy10-40]
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DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
RIN 0648-XX25
Small Takes of Marine Mammals Incidental to Specified Activities;
Exploratorium Relocation Project in San Francisco, 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
Exploratorium for an Incidental Harassment Authorization (IHA) to take
marine mammals, by harassment, incidental to pile driving during the
Exploratorium's relocation project. Pursuant to the Marine Mammal
Protection Act (MMPA), NMFS is proposing to issue an IHA to the
Exploratorium to incidentally harass, by Level B harassment only, four
species of marine mammals during the specified activity within a
specific geographic area and is requesting comments on its proposal.
DATES: Comments and information must be received no later than August
23, 2010.
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 providing email comments is 0648-XX25@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 http://www.nmfs.noaa.gov/pr/permits/
incidental.htm without change. All Personal Identifying Information
(for example, name, address, etc.) voluntarily submitted by the
commenter may be publicly accessible. Do not submit Confidential
Business Information or otherwise sensitive or protected information.
A copy of the application 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:http://
www.nmfs.noaa.gov/pr/permits/incidental.htm. Documents cited in this
notice may also be viewed, by appointment, during regular business
hours, at the aforementioned address.
FOR FURTHER INFORMATION CONTACT: Michelle Magliocca or Jaclyn Daly,
Office of Protected Resources, NMFS, (301) 713-2289.
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 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
[[Page 42692]]
apply for an authorization to incidentally take small numbers of marine
mammals by harassment. Section 101(a)(5)(D) establishes a 45-day time
limit for NMFS review of an application followed by a 30-day public
notice and comment period on any proposed authorizations for the
incidental harassment of marine mammals. Within 45 days of the close of
the comment period, NMFS must either issue or deny the authorization.
A. 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 April 28, 2010, NMFS received an application from the
Exploratorium, a nature, science, art and technology museum, requesting
an IHA for the take, by Level B harassment, of small numbers of Pacific
harbor seals (Phoca vitulina richardii), California sea lions (Zalophus
californianus), harbor porpoises (Phocoena phocoena), and gray whales
(Eschrichtius robustus) incidental to relocation of the Exploratorium
museum. Upon receipt of additional information, NMFS determined the
application complete and adequate on June 1, 2010.
The Exploratorium proposes to relocate from the Palace of Fine Arts
to Piers 15 and 17, along San Francisco's waterfront. The relocation
project would include the installation, repair, and removal of piles at
Pier 15, removal of wharf decking between Piers 15 and 17, and
expansion of the southern portion of Pier 15. The Exploratorium
proposes to install up to 69 new steel piles and repair and remove
existing piles by hydraulic or hand-held cutting tools. Because pile
driving has the potential to result in marine mammal harassment, NMFS
is proposing to issue an IHA for take incidental to this specified
activity.
Description of the Specified Activity
The Exploratorium proposes to relocate from 3601 Lyon Street to
Piers 15 and 17, along the Embarcadero of San Francisco's waterfront.
The relocation project is scheduled to commence as early as September
2010 and construction would continue throughout a 26-month period.
However, of the activities associated with the relocation, only pile
driving has the potential to result in marine mammal take and this
activity is expected to be complete by the spring of 2011.
To make room for the new Exploratorium, a maximum of 69 various
sized steel piles (thirty 72-inch, twenty six 24-inch, and thirteen 20-
inch diameter piles) would be installed around Piers 15 and 17 using a
vibratory hammer (Table 1). Between two and five steel piles (average
of three piles) would be installed daily, depending on their size and
the amount of time necessary to install them. Each pile would take
approximately 30 minutes to install followed by at least one hour
break, the minimum amount of time needed to reset the hammer and next
pile. In total, the Exploratorium anticipates conducting 28 hours of
pile driving, with 15 hours spent on 72-inch piles, five hours spent on
20-inch piles, and eight hours spent on 24-inch piles. All piles would
be installed with an ICE 14122 (or similar) vibratory hammer; however,
it may be necessary to seat a pile using an impact hammer. Based on the
ground sediments and the depth of pile driving needed, the use of an
impact hammer is not anticipated for the smaller 20-inch and 24-inch
piles but may be needed for the large diameter 72-inch piles. Should an
impact hammer be necessary, the Exploratorium would use a steam or
diesel-powered hammer delivering between 80,000 and 110,000 ft-lbs per
blow. For 20, 24, and 72-inch piles, the amount of strikes per pile
would be limited to 120, 25, and 5, respectively. Sound attenuation
devices (e.g., wood block, bubble curtain) would be used during any
impact hammering. In addition, impact hammering would not occur between
June 1 and November 30 to prevent injury to listed salmonids.
In addition to pile driving, the Exploratorium would repair or
remove existing piles (Table 1) and remove existing wharf decking.
Existing concrete piles would be removed by cutting them with a
hydraulic shear. The shear operates like a knife gate, with hydraulic
rams pushing a shear plate through the piling. The cutting shear would
be suspended from a crane on deck. In-water noise from this work would
be negligible. Pile repair would include installing a fiberglass shell
around damaged pile and filling the shell with concrete. The work would
be completed by divers using hand tools and does not involve loud
noise. Furthermore, there are no marine mammal haul out sites at Piers
15 and 17 and deck height in the area is at elevations generally too
high to facilitate marine mammal haul out. Deck removal and expansion
would occur outside of habitat for marine mammals. Therefore, removal
and expansion of the existing pier decking would not likely result in
harassment of marine mammals. Finally, there would be two to ten barges
or floats at any given time in the water to support construction
activities; however, these would be concentrated in the direct vicinity
of Piers 15/17. Because pile repair, pile removal, and use of barges do
not release loud sounds into the environment, marine mammal harassment
from these activities not anticipated.
Table 1. Summary of pile activities during the Exploratorium relocation
Activity
------------------------------------------------------------------------
Activity Maximum Number of Piles Location
------------------------------------------------------------------------
Installation of new 69 steel piles Marginal Wharf; South
piles (30 72-inch diameter Apron
steel piles,
26 24-inch steel piles,
and 13
20-inch steel piles)
------------------------------------------------------------------------
Repair of existing 1026 Pier 15; Valley Infill
piles Area;
Marginal Wharf; North
Apron
------------------------------------------------------------------------
Extension of existing 120 Valley Infill Area
piles
------------------------------------------------------------------------
Removal of existing 837 Marginal Wharf; Valley
piles-- cut at mudline Removal Area; South
Apron; Pier 15
------------------------------------------------------------------------
Removal of existing 306 Valley Removal Area;
piles--cut above mean Marginal Wharf
lower low water (MLLW)
------------------------------------------------------------------------
During the San Francisco Oakland Bay Bridge Project (SFOBB), the
California Department of Transportation (Caltrans), measured vibratory
driving sound levels from various pile types, sizes, and locations
around San Francisco Bay (Caltrans, 2007). Because no pile driving
noise data specific to the Exploratorium project exists, NMFS has
determined that hydroacoustic data from the Caltrans SFOBB project are
appropriate to use to estimate sound levels from the specified
activity. For
[[Page 42693]]
background, sound is a physical phenomenon 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 microPa'' and ``re: 1
microPa,'' respectively.
In 2007, Caltrans released a report summarizing typical and maximum
sound pressure levels (SPLs) measured during vibratory pile driving in
San Francisco Bay (Table 2). In summary, Caltrans measured sound
pressure levels (SPLs) 5 m from the hammer were below 180 dB root mean
square (rms) values. Most of the energy during vibratory pile driving
was below 600 Hz. NMFS notes that the vibratory hammers Caltrans used
to install the 72-inch pile were the King Kong and Super Kong Driver
(Model 600). The hammer the Exploratorium proposes to use is 40% of the
energy of the King Kong hammer; therefore, source levels would be lower
for the relocation project as hammer noise levels are proportional to
blow energy. Vibratory pile driving measurements taken by Caltrans
approximately 11-13 kilometers (km) northeast of the Exploratorium in
similar depth water indicate that peak sound pressures drop off at a
rate of about 7 dB per doubling of distance. For comparison, spherical
spreading (20 log R) is characterized by a drop-off rate of 6 dB per
doubling of distance. Therefore, it is anticipated that noise from pile
driving will dissipate very quickly around the Exploratorium.
Table 2. Measured sound pressure levels during vibratory pile driving in
San Francisco Bay (Caltrans, 2007).
------------------------------------------------------------------------
Pile Type/Size Relative Water Depth SPL at 10 m (RMS)
------------------------------------------------------------------------
72-inch steel pile 5 meters Average = 170 dB
Loudest = 180 dB
------------------------------------------------------------------------
34-inch steel pile 5 meters Average = 170 dB
Loudest = 175 dB
------------------------------------------------------------------------
24-inch steel pile 5 meters Average = 160 dB
Loudest = 165 dB
------------------------------------------------------------------------
12-inch steel pile 5 meters Average = 155 dB
------------------------------------------------------------------------
Caltrans also conducted hydroacoustic surveys within San Francisco
Bay during impact pile driving of similar size piles proposed for use
by the Exploratorium (Table 3). Bubble curtains can provide between 5-
20 dB reduction in source level; however, this is highly directional
and a function of current and device effectiveness (Caltrans, 2009).
Therefore, distances to the Level A and Level B harassment isopleths
are based on estimated unattenuated source levels. These distances are
likely an overestimate of sound levels produced by pile driving using a
bubble curtain or wood cap.
Table 3. Measured unattenuated sound pressure levels in the near field
(10 m) during impact pile driving in San Francisco Bay (Caltrans, 2009).
------------------------------------------------------------------------
Pile Type/Size Relative Water Depth SPL at 10 m (RMS)
------------------------------------------------------------------------
96-inch steel pile 10 meters 205 dB
------------------------------------------------------------------------
60-inch steel pile <5 meters 195 dB
------------------------------------------------------------------------
36-inch steel pile <5 meters 190 dB
24-inch steel pile 5 meters 190 dB
------------------------------------------------------------------------
14-inch steel pile 15 meters 184 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, harbor porpoise, gray
whale, 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 U.S. Fish
and Wildlife Service. Therefore, these two species are not considered
further in this proposed IHA notice.
Pacific Harbor Seals
Pacific harbor seals are found in the 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 strategic 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 north side of Yerba
Buena Island is the closest haul out area to the relocation project,
approximately 3 km from Piers 15 and 17. 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 the new Exploratorium site 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 in the water, 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, the lower limit remains at 75 Hz but the highest
audible frequencies are only around 30 kHz (Southall et al., 2007).
[[Page 42694]]
California Sea Lions
California sea lions are found 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 abundance of the U.S. stock is estimated to be 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 strategic 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 haul out on
floating docks (e.g., Pier 39 around Fishermen's Wharf) and on buoys
throughout the Bay. Breeding season begins in May and lasts until
August, with most pups born by July. While onshore, California sea
lions often form groups of several hundred animals. No sea lion
haulouts are located around the Exploratorium. However, sea lions
observed within this area may be transiting to and from nearby piers or
opportunistically foraging.
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 U.S. waters are
divided into 10 stocks, based on genetics, movement patterns, and
management. Any harbor porpoises encountered during the Exploratorium
relocation would likely be part of the San Francisco-Russian River
stock which has an estimated abundance of 9,189 animals. Abundance of
the San Francisco-Russian River stock appeared to be stable or
declining between 1988 and 1991 and has steadily increased since 1993,
although this increase is not statistically significant. 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). 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
strategic 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 will
occasionally enter rivers and bays, including San Francisco Bay, along
the coast, but in very low numbers. They could potentially be in the
action 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 strategic 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
Pile driving at the Exploratorium's new location may temporarily
impact marine mammal behavior within the action area due to elevated
in-water noise levels. No pinnipeds on haulouts would be affected as
the closest haulout is approximately 3 kms away; therefore, in-air
noise is not a concern. Marine mammals are continually exposed to many
sources of sound. Naturally occurring sounds such as lightning, rain,
sub-sea earthquakes, and biological sounds (e.g., snapping shrimp,
whale songs) are ubiquitous throughout the world's oceans. 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 (RLs)
will depend on the nature of the sound source, ambient noise
conditions, and the sensitivity of the receptor to the sound
(Richardson et al., 1995). Type and significance of marine mammal
reactions to noise are likely to dependent on a variety of factors
including, but not limited to, the behavioral state (e.g., feeding,
traveling, etc.) of the animal at the time it receives the stimulus,
frequency of the sound, distance from the source, and the level of the
sound relative to ambient conditions (Southall et al., 2007).
Hearing Impairment
Temporary or permanent hearing impairment is possible when marine
mammals are exposed to very loud sounds. Hearing impairment is measured
in two forms: temporary threshold shift (TTS) and permanent threshold
shift (PTS). There are no empirical data for onset of PTS in any marine
mammal; therefore, PTS-onset must be estimated from TTS-onset
measurements and from the rate of TTS growth with increasing exposure
levels above the level eliciting TTS-onset. PTS is presumed to be
likely if the hearing threshold is reduced by [gteqt] 40 dB (i.e., 40
dB of TTS). Due to proposed mitigation measures and source levels, NMFS
does not expect that marine mammals would be exposed to levels that
could elicit PTS; therefore, it will not be discussed further.
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, in cases of strong TTS,
days. For sound exposures at or somewhat above the TTS-onset threshold,
hearing sensitivity recovers rapidly after exposure to the noise 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
[[Page 42695]]
pinniped data from Kastak et al. (2005), indicating that a tested
harbor seal showed a TTS of around 6 dB when exposed to a nonpulse
noise at SPL 152 dB re: 1 microPa for 25 minutes. In contrast, a tested
sea lion exhibited TTS-onset at 174 dB re: 1 microPa 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 microPa (peak-to-peak) (Finneran et al., 2003). There is no
information on species-specific TTS for harbor porpoises or gray
whales.
There are limited data available on the effects of non-pulse noise
(e.g., vibratory pile driving) on pinnipeds in-water; however, field
and captive studies to date collectively suggest that pinnipeds do not
strongly react to exposures between 90-140 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 (ADH) around nine sites. Seals came within 44 m of
the active ADH and failed to demonstrate any behavioral response when
received SPLs were estimated at 120-130 dB. In a captive study
(Kastelein, 2006), a group of seals were collectively subjected to data
collection and communication network (ACME) non-pulse sounds at 8-16
kHz. Exposures between 80-107 dB did not induce strong behavioral
responses; however, a single observation at 100-110 dB indicated an
avoidance response at this level. The group returned to baseline
conditions shortly following exposure. Southall et al. (2007) notes
contextual differences between these two studies noting that the
captive animals were not reinforced with food for remaining in the
noise fields, whereas free-ranging subjects may have been more tolerant
of exposures because of motivation to return to a safe location or
approach enclosures holding prey items. While most of the pile driving
will be vibratory, a small portion of piles may be driven using an
impact hammer (pulse noise) and sound attenuation devices, resulting in
anticipated hydroacoustic levels between 164 and 179 dB RMS. Southall
et al. (2007) reviewed relevant data from studies involving pinnipeds
exposed to pulse noise and concluded that exposures to 150 to 180 dB
(approximate source level range for vibratory pile driving) generally
have limited potential to induce avoidance behavior.
Vibratory pile driving emits low frequency broadband noise, all of
which may be detectable by marine mammals within the action area.
However, lower frequency hearing animals such as pinnipeds and gray
whales are likely to be able to hear the sound better and farther away
than the harbor porpoise, who has a hearing range of 200 Hz-180 kHz
(Southall et al., 2007), as most of the energy during vibratory pile is
expected to be below 600 Hz (Caltrans 2007). No known data exists for
sound levels resulting from the type of vibratory hammer and pile sizes
that would be used at the Exploratorium; 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 Exploratorium are expected to be substantially lower
because the vibratory hammer being used is approximately 40 percent of
the energetic capacity of the ``King Kong'' hammer and will not be used
at full capacity. 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, may also 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 (as described
in Richardson et al., 1999) due to the amount of anthropogenic use
within the action area and San Francisco Bay as a whole.
Pacific harbor seal and California sea lion pupping season is
outside of the temporal pile driving schedule; therefore, no impacts to
reproduction are anticipated. It is expected that marine mammals
exposed to pile driving noise would be using the adjacent waters around
the Exploratorium's project site for foraging or as a daily migration
route between foraging grounds and haul out locations. Harbor porpoises
also may use the adjacent waters for foraging and may pass through the
area during pile driving. Gray whales are not expected to forage in the
activity area, but may display behavioral changes in response to noise
if they enter San Francisco Bay and transit or linger around the action
area during their annual migration.
Any impacts to marine mammal behavior are expected to be temporary.
First, animals may avoid the area around the hammer; thereby reducing
exposure. Second, pile driving does not occur continuously throughout
the day. As described above, the vibratory hammer only operates for
about 30 minutes followed by at least a one hour break. Two to five
pilings are anticipated to be driven per day, resulting in a total of
1-2.5 hours of pile driving within any given 24 hour period. Limiting
pile driving to less than three hours per day would allow for minimal
disruption of foraging or dispersal throughout the habitat. Any
disturbance to marine mammals is likely to be in the form of temporary
avoidance or alteration of opportunistic foraging behavior near the
pile driving location. In addition, because pile driving is anticipated
to be accomplished using only a vibratory hammer, marine mammal injury
or mortality is not anticipated. If an impact hammer is used, a
protected species observers (PSO) would be on watch to implement pile
driver shut down, a mitigation measure designed to prevent animals from
being exposed to injurious level sounds. For these reasons, any changes
to marine mammal behavior are expected to be temporary and result in a
negligible impact to affected species and stocks.
Anticipated Effects on Habitat
On May 28, 2010, the NMFS Southwest Regional Office concluded
section 7 and Essential Fish Habitat (EFH) consultation, under the ESA
and Magnuson Stevens Fishery Conservation and Management Act (MSFCMA),
respectively, with the U.S. Army Corps of Engineers (Corps) on issuance
of a Corps permit to the Exploratorium. In summary, NMFS Southwest
Regional Office found that the proposed construction activities may
affect ESA-listed fish by generating increased levels of turbidity and
sound; however, these impacts are expected to be minor, localized, and
short term. As such, NMFS Southwest Regional Office concurred with the
Corps determination that impacts from the Exploratorium's project would
not result in adverse impacts to ESA-listed fish or their critical
habitat. NMFS Southwest Regional Office also determined that the
proposed project would adversely affect EFH for various federally-
managed species within the Pacific Groundfish, Coastal Pelagic, and
Pacific Salmonid Fishery Management Plans; however, they also
determined that the proposed action contains adequate measures to
avoid, minimize, mitigate, or otherwise offset the adverse effects to
EFH.
Marine mammals and fish may occupy the same habitat. Pile driving
noise would result in degradation of in-water habitat; however, this
impact would be short term and localized. Installation of new piles
would be permanent; however, overall site
[[Page 42696]]
conditions are anticipated to be substantively unchanged from existing
conditions for marine mammals following project implementation.
Therefore, following results of consultation under the ESA and MSFCMA,
NMFS has preliminarily determined impacts to marine mammal habitat are
negligible.
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 Exploratorium has proposed the following mitigation measures to
help ensure the least practicable adverse impact on marine mammals:
Limited Use of an Impact Hammer
All piles would be installed using a vibratory pile driver unless
sufficient depth cannot be reached, at which point an impact hammer may
be used. In the event that an impact hammer is necessary, a bubble
curtain, wood block, or both would be used as an attenuation device to
reduce hydroacoustic sound levels to avoid the potential for injury.
With the use of these devices, hydroacoustic source levels are
anticipated to be between 164 and 179 dB RMS during impact hammering.
Establishment of a Safety Zone
During all in-water impact pile driving, the Exploratorium would
establish a preliminary marine mammal safety zone of 500 m around each
pile before pile driving commences. No safety zone for vibratory pile
driving is necessary as source levels will not exceed the Level A
harassment threshold.
Pile Driving Shut Down and Delay Procedures
If a PSO observes a marine mammal within or approaching the safety
zone prior to start of impact pile driving, the PSO would notify the
Resident Engineer (or other authorized individual) who would then be
required to delay pile driving until the marine mammal has moved
outside of the safety zone or if the animal has not been resighted
within 15 minutes. If a marine mammal is sighted within or on a path
toward the safety zone during pile driving, pile driving should cease
until that animal has cleared and is on a path away from the safety
zone or 15 minutes has lapsed since the last sighting. In addition, if
a marine mammal not authorized to be taken under the IHA (e.g.,
humpback whale) is observed within the Level B harassment zone (1900
m), pile driving would be delayed until that animal has cleared and is
on a path away from the safety zone or 15 minutes 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%
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%
energy, followed by a 1-minute waiting period, then two subsequent
three-strike sets. The soft-start procedure would be conducted prior to
driving each pile if vibratory hammering ceases for more than 30
minutes.
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 populations of marine
mammals that are expected to be present.
The Exploratorium must designate at least one biologically-trained,
on-site individual, approved in advance by NMFS, to monitor the 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 Level A
harassment zone (preliminary set at 500 m). In addition, at least one
NMFS-approved PSO would conduct behavioral monitoring in and around the
Exploratorium at least two days per week between March 1 and November
30 to estimate take and evaluate the behavioral impacts pile driving
has on marine mammals out to the Level B harassment isopleth (1,900 m).
Should a non-authorized marine mammal (i.e. humpback whale) be observed
at any time in this zone, the aforementioned shut down and delay
procedures would be followed.
As set forth in the Exploratorium's application to the Corps,
monitoring for herring spawning events would be conducted on a daily
basis between December 1 and February 28. This PSO would also monitor
for marine mammals within and around the Level B harassment area. In
addition to stationing a PSO to monitor for herring, the Exploratorium
would cease pile driving for two weeks should a herring spawning event
occur (a measure designed to reduce impacts to fish). Pinniped presence
during such events can be sporadic and unpredictable; therefore, the
requirements set forth under ESA and EFH consultation also minimize and
allow for monitoring of impacts to marine mammals.
PSOs would be provided with the equipment necessary to effectively
monitor for marine mammals (e.g., high-quality binoculars, compass, and
range-finder) in order to determine if animals have entered into the
harassment isopleths and to record species, behaviors, and responses to
pile driving. PSOs would be required to submit a
[[Page 42697]]
report to NMFS within 120 days of expiration of the IHA or completion
of pile driving, whichever comes first. The report would include data
from marine mammal sightings (e.g., species, group size, 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 Exploratorium's 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 who are within the action area. Marine mammals may avoid the
area or halt any behaviors (e.g., foraging) at time of exposure. Due to
the short duration of pile driving per day (1- 2.5 hours), animals are
not anticipated to be exposed multiple times per day.
Current NMFS practice regarding exposure of marine mammals to
anthropogenic noise is that in order to avoid the potential for injury
of marine mammals (e.g., PTS), cetaceans and pinnipeds should not be
exposed to impulsive sounds of 180 and 190 dB rms 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 rms for impulse sounds (e.g.,
impact pile driving) and 120dB rms for non-pulse noise (e.g., vibratory
pile driving), but below the aforementioned thresholds. These levels
are also considered precautionary.
Based on empirical measurements taken by Caltrans (which are
presented in the Description of Specified Activities section above),
estimated distances to NMFS current threshold sound levels from pile
driving during the Exploratorium's relocation project are presented in
Table 4. These estimates are based on the worst case scenario of
driving the 72- inch steel piles but would be carried over for all pile
driving. Note that despite short distances to the Level A harassment
isopleth, the Exploratorium has proposed to implement a preliminary
500-m marine mammal safety zone until empirical pile driving
measurements can be made and distances to this threshold isopleth can
be verified.
Table 4: Modeled underwater distances to NMFS' marine mammal harassment
threshold levels.
------------------------------------------------------------------------
Level B Level B
Level A (190/180 harassment (160 harassment (120
dB) dB) dB)
------------------------------------------------------------------------
Impact hammering 20 m (w/o sound 100 m n/a
attenuation
device)
------------------------------------------------------------------------
Vibratory n/a n/a 1900 m
hammering
------------------------------------------------------------------------
The estimated number of marine mammals potential taken was based on
marine mammal monitoring reports prepared by Caltrans during similar
activities in San Francisco Bay and on discussions with the NMFS
Southwest Regional Office. Caltrans' SFOBB marine mammal monitoring
reports were used to estimate the number of pinnipeds near the
Exploratorium project area as the SFOBB site and Exploratorium are
relatively close to each other and are similar in bathymetric features
(e.g., water depth, substrate). However, monitoring conducted for the
SFOBB project has been in close proximity to a haul out area, while the
Exploratorium project is in an area of high commercial boat activity
with no haul out sites. Therefore, the Caltrans data likely
overestimates marine mammal abundance for the Exploratorium project
area. Based on consultation with the NMFS Southwest Regional Office and
review of Caltrans monitoring reports for pile driving activities in
San Francisco Bay, the Exploratorium requested a total take of two
Pacific harbor seals, one California sea lion, and one gray whale per
day of pile driving. Upon further consultation with NMFS Southwest
Regional Office, NMFS is proposing to include harbor porpoise as a
species potentially taken by pile driving, due to the recorded, albeit
infrequent, sightings of harbor porpoises within San Francisco Bay.
The Exploratorium estimates an average of three piles would be
driven in a single day. Given 69 piles in total, pile driving would
occur for 19 days over the life of the project. Therefore, NMFS is
proposing to authorize annual take, by Level B harassment only, of 38
Pacific harbor seals, 19 California sea lions incidental to the
Exploratorium's pile driving activities. Due to the infrequent, but
potential presence of harbor porpoise and gray whales in the area, NMFS
is also proposing to authorize the take of 28 harbor porpoise and five
gray whales, annually, based on consultation with the NMFS Southwest
Regional Office, NMFS. These numbers indicate the maximum number of
animals expected to occur within the Level B harassment isopleth (1,900
m). Estimated and proposed level of take of each species is less than
one percent of the affected stock population and therefore is
considered small in relation to the population numbers previously set
forth.
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 (e.g., will the takes occur in an
area or time of significance for marine mammals, are takes occurring to
a small, localized population?).
As described above, marine mammals would not be exposed to
activities or sound levels which would result in injury (e.g., PTS),
serious injury, or mortality. Pile driving would occur in shallow
coastal waters of San Francisco Bay to stocks occurring throughout
California, and, for gray whales, the eastern Pacific Ocean. The action
area (waters around Piers 15-17) is not considered as providing
significant habitat for harbor seals. The closest haulout is 3 kms away
on Yerba Buena Island; however, noise levels about NMFS harassment
thresholds would only extend to 1,900 m in-water. Marine mammals
approaching the action area would likely be traveling or
opportunistically foraging. However, marine mammals foraging on herring
runs would not be affected by
[[Page 42698]]
construction because the Exploratorium would not conduct pile driving
for two weeks if a herring run is observed by the on-site PSO, who
would monitor the area daily between December 1- February 28. In
addition, a PSO would monitor for marine mammals twice a day to
estimate take and verify impacts to marine mammals are not above those
described here. The amount of take the Exploratorium 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. As previously noted, no affected marine mammals are listed
under the ESA or considered strategic under the MMPA.
Marine mammals may be temporarily impacted by pile driving noise.
However, marine mammals are expected to avoid the area, thereby
reducing exposure and impacts. Further, although the relocation project
is expected to take up to two years, installation of the 69 steel piles
would only occur for approximately 19 days. Further, San Francisco Bay
is a highly industrialized area and species such as harbor seals and
California sea lions flourish throughout the Bay. Therefore, animals
are likely tolerant or habituated to anthropogenic disturbance,
including low level vibratory pile driving operations, and noise from
other anthropogenic sources (e.g., vessels in the adjacent shipping
lane) may mask construction related sounds. Finally, breeding and
pupping season occur outside of the proposed pile driving timeframe;
therefore, no disruption to reproductive behavior is anticipated. 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 Exploratorium's
relocation project 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
additional authorization for incidental harassment for the ongoing
project. Upon completion, this EA will be available on the NMFS website
listed in the beginning of this document.
Dated: July 16, 2010.
James H. Lecky,
Director, Office of Protected Resources, National Marine Fisheries
Service.
[FR Doc. 2010-18002 Filed 7-21-10; 8:45 am]
BILLING CODE 3510-22-S
