[Federal Register Volume 65, Number 10 (Friday, January 14, 2000)]
[Notices]
[Pages 2375-2381]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-953]
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DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
[I.D. 010599B]
Small Takes of Marine Mammals Incidental to Specified Activities;
Seismic Retrofit of the Richmond-San Rafael Bridge, San Francisco Bay,
CA
AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and
Atmospheric Administration (NOAA), Commerce.
[[Page 2376]]
ACTION: Notice of issuance of an incidental harassment authorization.
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SUMMARY: In accordance with provisions of the Marine Mammal Protection
Act (MMPA) as amended, notification is hereby given that an Incidental
Harassment Authorization (IHA) has been issued to the California
Department of Transportation (CALTRANS) to take small numbers of
Pacific harbor seals and possibly California sea lions, by harassment,
incidental to seismic retrofit construction of the Richmond-San Rafael
Bridge (the Bridge), San Francisco Bay, (the Bay) CA.
DATES: This authorization is effective from September 1, 2000, through
August 31, 2001.
ADDRESSES: A copy of the application and an Environmental Assessment
(EA) may be obtained by writing to Donna Wieting, Chief, Marine Mammal
Conservation Division, Office of Protected Resources, National Marine
Fisheries Service, 1315 East-West Highway, Silver Spring, MD 20910-
3225, or by telephoning one of the contacts listed here.
FOR FURTHER INFORMATION CONTACT: Kenneth R. Hollingshead, Office of
Protected Resources, NMFS, (301) 713-2055, or Christina Fahy, Southwest
Regional Office, NMFS, (562) 980-4023.
SUPPLEMENTARY INFORMATION:
Background
Section 101(a)(5)(A) and (D) of the MMPA (16 U.S.C. 1361 et seq.)
directs the Secretary of Commerce to allow, upon request, the
incidental, but not intentional, taking of marine mammals by U.S.
citizens who engage in a specified activity (other than commercial
fishing) within a specified geographical region if certain findings are
made and either regulations are issued or, if the taking is limited to
harassment, a notice of a proposed authorization is provided to the
public for review.
Permission may be granted if NMFS finds that the taking will have a
negligible impact on the species or stock(s) and will not have an
unmitigable adverse impact on the availability of the species or
stock(s) for subsistence uses and that the permissible methods of
taking and requirements pertaining to the 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.''
Subsection 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. The MMPA now defines ``harassment'' as:
...any act of pursuit, torment, or annoyance which (a) has the
potential to injure a marine mammal or marine mammal stock in the
wild; or (b) 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.
Subsection 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
small numbers of marine mammals. Within 45 days of the close of the
comment period, NMFS must either issue or deny issuance of the
authorization.
Summary of Request
On November 9, 1998, NMFS received an application from CALTRANS,
requesting reauthorization of an IHA issued on December 16, 1997 (62 FR
6704, December 23, 1997). This authorization would be for the possible
harassment of small numbers of Pacific harbor seals (Phoca vitulina)
and possibly some California sea lions (Zalophus californianus)
incidental to seismic retrofit construction of the Bridge.
The Bridge is being seismically retrofitted to withstand a future
severe earthquake. Construction is scheduled to extend through December
2003. A detailed description of the work planned is contained in the
Final Natural Environmental Study/Biological Assessment for the
Richmond-San Rafael Bridge Seismic Retrofit Project. (CALTRANS, 1996).
Among other things, seismic retrofit work will include excavation
around pier bases, hydro-jet cleaning, installation of steel casings
around the piers with a crane, installation of micro-piles, and
installation of precast concrete jackets. Foundation construction will
require approximately 2 months per pier, with construction occurring on
more than one pier at a time. In addition to pier retrofit,
superstructure construction and tower retrofit work will also be
carried out. Because seismic retrofit construction between piers 52 and
57 has the potential to disturb harbor seals hauled out on Castro
Rocks, a reauthorization of the IHA is warranted. The duration for the
seismic retrofit of foundation and towers on piers 52 through 57, which
did not take place as planned during 1998, will be approximately 7 to 8
months.
Comments and Responses
A notice of receipt of the application and proposed authorization
was published on February 16, 1999 (64 FR 7627), and a 30-day public
comment period was provided on the application and proposed
authorization. Comments were received from two environmental
organizations, two research scientists, and one Federal agency.
On May 19, 1999, CALTRANS requested a delay in the issuance of the
IHA with an effective date of September 1, 1999. On July 7, 1999,
CALTRANS requested a modification of condition 5(d) that was contained
in its 1997 IHA to allow pile installation during the night for
construction of the Concrete Trestle Section (CTS) of the Bridge,
provided the noise does not exceed 86 dBA at the edge of the work
exclusion zone at Castro Rocks. NMFS review of this request is also
contained in this section. Finally, in December, 1999, CALTRANS
informed NMFS that work on the Bridge would not begin until September,
2000.
Comment 1: Earthwatch provided detailed scientific evidence and
information that the stock of Pacific harbor seals (Phoca vitulina
richardsii) should be considered by NMFS as a separate population
stock, including reduced gene flow with other populations, and
geographic and demographic isolation.
Response: The scientific evidence and information provided by
Earthwatch has been forwarded to NMFS scientists for review and
evaluation. If experts on harbor seal genetics agree that the data
support the conclusion, NMFS will present the case to the Pacific
Scientific Review Group before revising the stock assessment reports to
change Pacific harbor seal stock structure.
Comment 2: Earth Island Institute (EII)/Earthlaw letters contend
that the Boat Exclusion Zone (BEZ), which is a mitigation requirement
in the prior IHA, has no scientific basis and does little to eliminate
seal disturbance due to boat traffic. Scientific information from
Bolinas Lagoon indicates that harbor seals often flush into the water
when boats or other craft come within 200 m (656.2 ft) of a haulout
site, and using that example, Earthlaw contends that boats will come
close enough to Castro Rocks to flush harbor seals approximately 95
percent of the time. Data summarized by EII suggest that an exclusion
zone of 200 m (656.2 ft) will
[[Page 2377]]
still result in at least a partial flush of seals of between 24 and 63
percent of the time.
Response: The requirement of the MMPA is that, through mitigation,
impacts on marine mammals be reduced to the lowest level practicable;
it is not a requirement to eliminate those impacts. The 1997 IHA
required the northern boundary of the exclusion zone to be located 76 m
(250 ft) from the most northern tip of Castro Rocks and the southern
boundary to be located 76 m (250 ft) from the most southern tip of
Castro Rocks. The eastern boundary was located 91 m (300 ft) from the
most eastern tip of Castro Rocks and the western boundary was located
91 m (300 ft) from the most western tip of Castro Rocks. These
distances were greater than initially proposed (see 62 FR 46480,
September 3, 1997). In actuality, the BEZ is a rectangle with minimum
distances set at 109 m (357.6 ft) to the west of the haulout site, 182
m (597 ft) to the east, 80 m (262.5 ft) to the north and 48 m (157.5
ft) to the south.
Data collected by the harbor seal survey team at Castro Rocks
indicate that watercraft passing within 100 m (328 ft) of the haul-out
site caused at least a partial flush 30 percent of the time. Watercraft
passing between 100 and 200 m (328 and 656.2 ft) from the rocks caused
at least a partial flush 20 percent of the time. Combined, watercraft
passing within 200 m (656.2 ft) of the rocks caused at least a partial
flush 27 percent of the time. While Earthlaw references Bolinas Lagoon
to justify a minimum BEZ for Castro Rocks, harbor seal responses to
disturbance vary depending upon location. Bolinas Lagoon is a different
situation and may not be comparable to Castro Rocks (Sarah Allen, pers
commun. to the harbor seal survey team). For example, at Castro Rocks,
harbor seals located on the rocks closest to the shipping channel to
the west of the haulout appear to have habituated to the presence of
boats within the channel. However, the behavior of the watercraft, in
conjunction with the distance, often dictates whether seals are
disturbed (Green and Grigg, 1999; see Suryan and Harvey, 1999).
As a result of the comment however, NMFS reviewed the dimensions of
the BEZ and determined that the northern and southern boundaries do not
conform with NMFS guidelines for California that boats must remain at
least 91 m (300 ft) from seals and sealions that are on land or rocks.
As a result the northern and southern boundaries of the BEZ have been
extended in the IHA from 76 m (250 ft) to 91 m (300 ft). Nevertheless,
it should be noted neither the extension of the northern edge of the
BEZ, nor the previous BEZ will prohibit work boats from accessing the
Bridge from the north side for scheduled work on the Bridge.
Comment 3: The IHA requires that the BEZ will be restricted as a
controlled access area and will be marked off with buoys and warning
signs for the entire year (2-5(b)). Although construction activities
have been ongoing for many months now, no warning buoys or signs
identifying the BEZ have been installed. NMFS should ensure that buoys
and signs are in place before it issues any new IHA.
Response: According to CALTRANS, seismic retrofit construction has
not begun on the Richmond-San Rafael Bridge. Once construction begins,
the buoys and warning signs will be installed and the BEZ will become a
controlled access area in accordance with the IHA.
Comment 4: The sources of disturbance and the distance between the
haul-out and the disturbance event are critical pieces of information
since they may be used to evaluate the effectiveness of mitigation.
This information should be recorded and provided in the weekly reports.
In addition, disturbance events caused by workmen should not be grouped
with disturbance caused by natural events. Workman disturbances are
directly relevant to potential future impacts and mitigation.
Response: Because seismic retrofit work has not yet begun on the
Bridge, the instances of recorded ``other construction'' disturbances
(e.g., routine bridge maintenance) in the area of the haul out site are
very rare, and were therefore combined with other miscellaneous
categories for the purposes of the interim report. Once seismic
retrofit work begins, the monitoring protocol will enable CALTRANS
observers to distinguish between disturbance which may be caused by the
CALTRANS retrofit construction, and those due to all other causes.
Comment 5: The monitoring program currently makes no provision for
enforcing noise restrictions contained in the IHA. The IHA includes a
year-round limit on construction noise of 86 dBA at 50 ft (15 m)
between 9 p.m. and 7 a.m. It also includes an unquantified limit on
construction noise levels for 24 hours per day in the vicinity of
Castro Rocks during the work closure period (pupping/molting season).
The limit on construction noise levels during the pupping season needs
to be quantified by NMFS. In addition, for both the nighttime and work
closure noise restriction periods, noise levels should be defined in
term of dBA at the haulout site.
Response: Because NMFS is unaware of any single noise level that
will not result in adult and/or pup harbor seals remaining on the beach
and still allow work on the Bridge to proceed, at this time NMFS has
chosen not to establish sound pressure level (SPL) limits at the Castro
Rocks haulout as recommended by Earthlaw. NMFS believes, based on
information collected at Vandenberg Air Force Base, that the noise
level sufficient for harbor seals to leave the beach is around 80 dBA,
but this may depend upon the type of noise, intensity, and duration,
which could be different at the Bridge from that experienced by harbor
seals at Vandenberg. With a limit of 86 dBA at 50 ft (15 m) for work on
the Bridge between 9 p.m. and 7 a.m., NMFS believes that noise levels
have been mitigated to the greatest extent practicable. However, NMFS
intends to monitor the activity at the Bridge to ensure that 86 dBA is
the lowest level practicable. NMFS also believes that the pupping on
Castro Rocks during the period of this IHA will be protected from
excessive noise levels because work on the Bridge will not begin until
September, 2000, and proceed from west to east. CALTRANS does not
expect to begin retrofit work in the vicinity of Castro Rocks until
approximately August, 2001. This date will allow CALTRANS' biological
observers time to assess impacts from construction on harbor seals
prior to reaching the area affecting Castro Rocks. NMFS believes that
the noise issue is more likely to be relevant in any IHA authorized
after August 31, 2001, when work will continue on the portion of the
Bridge nearest to Castro Rocks. As a result, NMFS believes that a
reassessment of this concern should be made during the next IHA
renewal.
Contrary to the statement, NMFS enforces mitigation measures
contained in IHAs. Violations of IHAs may result in suspension or
revocation of the IHA; it may also result in penalties under the MMPA.
However, NMFS does not believe that biological observers, hired by
CALTRANS and/or NMFS, should be expected to monitor compliance with
Federal or state regulations or permits. Generally, if calibrated sound
monitoring equipment is used by an observer(s) in order to quantify the
sound pressure level as seals leave the haulout, then that data could
later be used during an enforcement proceeding.
[[Page 2378]]
Comment 6: On July 7, 1999, CALTRANS requested a modification to
condition 5(d), that was contained in its 1997 IHA, to allow pile
installation during the night (i.e., during the 9 p.m. to 7 a.m. time
period) for construction of the CTS of the Bridge, provided the noise
does not exceed 86 dBA at the edge of the work exclusion zone at Castro
Rocks.
Response: NMFS has reviewed the request by CALTRANS and has
determined that, because the CTS is located over 2.5 miles (4.0 km)
from Castro Rocks it should not have an effect on seals hauled out
there. Also, because the 9 p.m. to 7 a.m. pile driving prohibition is a
mitigation measure imposed for the welfare of humans, it should not be
required as a mitigation measure for marine mammal protection when and
where it is not necessary. Data provided by CALTRANS indicated that
noise levels from the pile driving equipment planned to be used at the
CTS will exceed the 86 dBA at 50 ft SPL limitation. The 86 dBA SPL will
be around 200 ft (61 m). Because of the distance between the CTS and
Castro Rocks, NMFS does not believe that the noise will be sufficient
to flush harbor seals off Castro Rocks. However, because sound monitor
equipment on Castro Rocks will monitor noise levels during this time,
if, because pile driving will continue after 9 p.m. at the CTS, seals
are not able to haul out at night, NMFS may need to amend the IHA, on
an emergency basis, to provide additional protection for the harbor
seals at Castro Rocks in order for the seals to haul out at night in
compensation for disruptions during the daytime. This haul-out ability
is apparently important for the seals. This concern was also expressed
by two seal biologists during the comment period. As a result, NMFS has
conditioned the IHA to limit construction noise levels 86 dBA no
greater than 50 ft (15 m) year-round between 9 p.m. and 7 a.m. for all
parts of the Bridge other than the CTS. At this time, NMFS has
insufficient information to waive this restriction for other sections
of the Bridge. Additional waivers would be considered a request for a
modification of the IHA, and, as such, would allow the public an
opportunity for comment.
Comment 7: It has been recommended that monitoring compliance with
noise restrictions be conducted by mounting a sound monitor on Rock A
at Castro Rocks with a remote recording system.
Response: A monitoring recorder will be established on Castro Rocks
to correlate SPLs with animal behavior.
Comment 8: Ongoing monitoring of only two of the alternative haul-
out sites in the Bay is insufficient to determine whether harbor seals
use alternative haulout sites as a result of disturbance at Castro
Rocks. EII recommends aerial counts, conducted three times per season,
over the entire Bay to determine whether seals are using other primary
or secondary haul-out sites in the Bay due to disturbance at Castro
Rocks. Unless all haulout sites are monitored, CALTRANS will not be
able to determine whether a decline in numbers at Castro Rocks due to
Project disturbance is resulting in a decline in the overall harbor
seal population in the Bay. Given the budget for the Project, 12 aerial
surveys per year will not be unduly burdensome or prohibitively
expensive, and will provide a much better understanding of Bay harbor
seal movement and status, as well as increased general knowledge of the
species (see 50 CFR Sec. 216.104) - monitoring should increase general
knowledge of the species).
Response: In the 1997/1998 IHA, NMFS required CALTRANS to monitor
harbor seal behavior on at least one additional haulout. CALTRANS
established monitoring programs on two alternative haulouts, at Yerba
Buena Island and Mowry Slough. Yerba Buena Island is in the central
Bay, Mowry Slough is in the southern part of the Bay. In addition, seal
biologists are monitoring the haulout at Corte Madera. Because these
four haulouts have the largest populations of seals, and because other
haul-outs cannot contain large numbers of seals, if seals abandon
Castro Rocks, it is likely that they will haul out on one or more of
these three haulouts.
At this time, NMFS scientists do not believe that aerial surveys
will provide sufficient scientific information on the impacts from
construction at the Bridge to warrant the expense. Primarily, aerial
surveys will detect only that portion of the harbor seal population
that has hauled out at the time of the overflight and at altitudes
necessary to avoid startling seals (1,000 ft (305 m)), pups would not
be detectable. Secondly, without additional studies, such as a mark-
recapture study, aerial surveys are unlikely to detect a decline in
harbor seal numbers due to a potential short-term abandonment of Castro
Rocks. Finally, while aerial surveys would provide information on the
current status of Bay harbor seals, a cause-and-effect relationship
between the construction work at the Bridge, and a decline in harbor
seals, if one occurs, would not be apparent.
Comment 9: Earthwatch requests NMFS to provide to them and to the
public copies of all weekly, interim, and final reports.
Response: CALTRANS will provide copies of reports to Earthwatch or
an organization chosen by Earthwatch to obtain these reports.
Comment 10: The monitoring and reporting program adopted in the
prior IHA and proposed for the renewal does not provide any feedback
mechanism for corrective action where the Project activities are
resulting in significant increased disturbance to harbor seals using
Castro Rocks. Such a corrective action mechanism is critical to prevent
the permanent loss of this key haulout site. Once harbor seals abandon
a site, there is a good likelihood that they will never return to it.
Accordingly, the IHA should contain a defined and enforceable
procedure to be followed whenever the weekly data demonstrates a
significant reduction in haulout site use at Castro Rocks. Once the
corrective action provision is triggered, Earthlaw recommends that
operations in the vicinity of Castro Rocks be temporarily halted for a
period of at least 48 hours, during which time survey monitors, NMFS
and Caltrans review the data to determine what is causing the reduced
site use and develop appropriate mitigating measures. Such a situation
could occur at any time of the year.
Response: NMFS will not require CALTRANS to stop work if seal
disturbances are observed because, it has been informed, certain
construction operations cannot be stopped in progress without
jeopardizing the structural integrity of the Bridge. In addition,
stopping construction will simply extend the period for harbor seal
disturbance. While NMFS does not believe that harbor seals will
permanently abandon Castro Rocks since disturbance at that location is
already frequent, NMFS does recognize that seismic retrofit on the
portion of the Bridge closest to Castro Rocks is likely to result in
frequent flushing of seals off the Rocks, and possibly short-term
abandonment. This period may last 7-8 months (the period estimated for
retrofit construction) or longer. In part because of the limited 6-
month work period, CALTRANS expects this work will take 2 years. With
nighttime noise restrictions, NMFS believes that seals will be able to
remain in the vicinity of Castro Rocks and haul-out during this quieter
time period. If seals fail to haul out at night, and do not appear to
be utilizing other nearby haulouts, NMFS will meet with CALTRANS staff
and marine mammal observers to determine whether additional mitigation
measures are practicable. Because any new
[[Page 2379]]
mitigation measures imposed through the IHA would be on an emergency
basis for the protection of harbor seals, advance notice and comment
will not be provided.
NMFS does not anticipate long-term abandonment of Castro Rocks as
existing traffic noise from the Bridge, commercial activities at the
Chevron Long Wharf, and considerable recreational boating and
commercial shipping that currently occur within the area have not
caused long-term abandonment. However, if long-term abandonment were to
occur at Castro Rocks, which is the haulout location for approximately
25 percent of the Bay harbor seals, this should not result in more than
a negligible impact on either Bay harbor seals, or on the Pacific
harbor seal stock itself. These animals are likely to either haul-out
at other Bay haulouts or leave the Bay. As a result, NMFS does not
expect the incidental harassment of harbor seals from construction
activities at the Bridge to have more than a negligible impact on the
Pacific Coast harbor seal stock.
Furthermore, if any unauthorized marine mammal taking (e.g.,
serious injury or mortality) occurs as a result of seismic retrofit
construction activities, CALTRANS will be subject to the penalties of
the MMPA and NMFS will reevaluate the appropriateness of the IHA before
CALTRANS reapplies for a new IHA next year, based on required reports
(see Reporting section). Comment 11: In its May 19, 1999, letter
CALTRANS requested that the IHA reauthorization be delayed until
September, 1999.
Response: NMFS noted that in its November, 1998 IHA application
that CALTRANS' work schedule did not include seismic retrofit work on
the Bridge until the summer of 1999. In its
May 19, 1999, letter CALTRANS noted that work would not begin until
February, 2000. That was later amended to September, 2000. Because
construction work would not begin prior to this time, and work would
progress from the west to east, marine mammals would not be subject to
incidental harassment prior to that month and therefore, an IHA is
unnecessary prior to that time. As a result, NMFS has made the IHA
effective for 1 year commencing on September 1, 2000. It should be
noted that this effective date in no way amends the February 15 through
July 31 work restrictions on work in the water and on retrofit work on
the Bridge between piers 52 through 57; instead, it authorizes the
incidental harassment of harbor seals and California sea lions while
work proceeds on other portions of the Bridge.
Description of Habitat and Marine Mammals Affected by the Activity
A description of the Bay ecosystem and its associated marine
mammals can be found in the CALTRANS application (CALTRANS 1997) and
CALTRANS (1996).
Castro Rocks are a small chain of rocky islands located next to the
Bridge and approximately 1500 ft (460 m) north of the Chevron Long
Wharf. They extend in a southwesterly direction for approximately 800
ft (240 m) from pier 55. The rocks start at about 55 ft (17 m) from
pier 55 and end at approximately 250 ft (76 m) from pier 53. The chain
of rocks is exposed during low tides and inundated during high tide.
Marine Mammals
General information on harbor seals and other marine mammal species
found in Central California waters can be found in Barlow et al.
(1995). The marine mammals likely to be found in the Bridge area are
limited to the California sea lion and harbor seal.
The California sea lion primarily uses the Central San Francisco
Bay area to feed. California sea lions are periodically observed at
Castro Rocks. No pupping or regular haulouts occur in the project area.
The harbor seal is the only marine mammal species expected to be
found in the Bridge area. A detailed description of harbor seals was
provided in the 1997 notification of proposed authorization (62 FR
46480, September 3, 1997) and is not repeated here. Corrections and
clarifications to the proposed authorization were provided in the
notice of IHA issuance (62 FR 67045, December 23, 1997).
Potential Effects on Marine Mammals
The impact to the harbor seals and California sea lions is expected
to be disturbance by the presence of workers, construction noise, and
construction vessel traffic. Disturbance from these activities is
expected to have a short-term negligible impact to a small number of
harbor seals and sea lions. These disturbances will be reduced to the
lowest level practicable by implementation of the proposed work
restrictions and mitigation measures (see Mitigation).
During the work period, harbor seal and, on rare occasions,
California sea lion incidental harassment is expected to occur on a
daily basis upon initiation of the retrofit work. If harbor seals no
longer perceive construction noise and activity as being threatening,
they are likely to resume their regular hauling out behavior. The
number of seals disturbed will vary daily depending upon tidal
elevations. It is expected that disturbance to harbor seals during peak
periods of abundance will not occur since construction activities will
not take place within the restricted work area during the peak period
(see Mitigation).
Whether California sea lions will react to construction noise and
move away from the rocks during construction activities is unknown. Sea
lions are generally thought to be more tolerant of human activities
than harbor seals and are, therefore, likely to be less affected.
Potential Effects on Habitat
Short-term impacts of the activities are expected to result in a
temporary reduction in utilization of the Castro Rocks haul out site
while work is in progress or until seals acclimate to the disturbance.
This will not likely result in any permanent reduction in the number of
seals at Castro Rocks. The abandonment of Castro Rocks as a harbor seal
haul out and rookery is not anticipated since existing traffic noise
from the Bridge, commercial activities at the Chevron Long Wharf used
for off-loading crude oil, and considerable recreational boating and
commercial shipping that currently occur within the area have not
caused long-term abandonment. In addition, mitigation measures and
proposed work restrictions are designed to preclude abandonment.
Therefore, as described in detail in CALTRANS (1996), other than
the potential short-term abandonment by harbor seals of part or all of
Castro Rocks during retrofit construction, no impact on the habitat or
food sources of marine mammals are likely from this construction
project.
Mitigation
Several mitigation measures to reduce the potential for general
noise will be implemented by CALTRANS as part of their activity.
General restrictions include: with the exception of the CTS, no piles
will be driven (i.e., no repetitive pounding of piles) on the Bridge
between 9 p.m. and 7 a.m.; an imposition of a construction noise limit
of 86 dBA at 50 ft (15 m) between 9 p.m. and 7 a.m.; and, a limitation
on construction noise levels for 24 hrs/day in the vicinity of Castro
Rocks during the pupping/molting restriction period.
To minimize potential harassment of marine mammals, NMFS proposes
to require CALTRANS to comply with the following mitigation measures:
(1) A February 15 through July 31 restriction
[[Page 2380]]
on work in the water south of the Bridge center line and retrofit work
on the Bridge substructure, towers, superstructure, piers, and pilings
from piers 52 through 57; (2) no watercraft will be deployed by
CALTRANS employees or contractors, during the year within the exclusion
zone located between piers 52 and 57, except for when construction
equipment is required for seismic retrofitting of piers 52 through 57;
and (3) minimize vessel traffic to the greatest extent practicable in
the exclusion zone when conducting construction activities between
piers 52 and 57. The boundary of the exclusion zone is rectangular in
shape (1700 ft (518 m) by 800 ft (244 m)) and completely encloses
Castro Rocks and piers 52 through 57, inclusive. The northern boundary
of the exclusion zone will be located 300 ft (91 m) from the most
northern tip of Castro Rocks, and the southern boundary will be located
300 ft (91 m) from the most southern tip of Castro Rocks. The eastern
boundary will be located 300 ft (91 m) from the most eastern tip of
Castro Rocks, and the western boundary will be located 300 ft (91 m)
from the most western tip of Castro Rocks. This exclusion zone will be
restricted as a controlled access area and will be marked off with
buoys and warning signs for the entire year.
Monitoring
NMFS will require CALTRANS to monitor the impact of seismic
retrofit construction activities on harbor seals at Castro Rocks.
Monitoring will be conducted by one or more NMFS-approved monitors.
CALTRANS is to monitor at least one additional harbor seal haulout
within San Francisco Bay to evaluate whether harbor seals use
alternative hauling-out areas as a result of seismic retrofit
disturbance at Castro Rocks.
The monitoring protocol will be divided into the Work Period Phase
(August 1 through February 14) and the Closure Period Phase (February
15 through July 31). During the Work Period Phase and Closure Period
Phase, the monitor(s) will conduct observations of seal behavior at
least 3 days/week for approximately one tidal cycle each day at Castro
Rocks. The following data will be recorded: (1) Number of seals and sea
lions on site; (2) date; (3) time; (4) tidal height; (5) number of
adults, subadults, and pups; (6) number of individuals with red pelage;
(7) number of females and males; (8) number of molting seals; and (9)
details of any observed disturbances. Concurrently, the monitor(s) will
record general construction activity, location, duration, and noise
levels. At least 2 nights/week, the monitor will conduct a harbor seal
census after midnight at Castro Rocks. In addition, during the Work
Period Phase and prior to any construction between piers 52 and 57,
inclusive, the monitor(s) will conduct baseline observations of seal
behavior at Castro Rocks and at the alternative site(s) once a day for
a period of 5 consecutive days immediately before the initiation of
construction in the area to establish pre-construction behavioral
patterns. During the Work Period and Closure Period Phases, the
monitor(s) will conduct observations of seal behavior, and collect
appropriate data, at the alternative Bay harbor seal haulout at least 3
days/week (Work Period) and 2 days/week (Closure Period), during a low
tide.
In addition, NMFS proposes to require that, immediately following
the completion of the seismic retrofit construction of the Bridge, the
monitor(s) will conduct observations of seal behavior, at Castro Rocks,
at least 5 days/week for approximately 1 tidal cycle (high tide to high
tide) each day, for one week/month during the months of April, July,
October, and January. At least 2 nights/week during this same period,
the monitor will conduct an additional harbor seal census after
midnight.
Reporting
CALTRANS will provide weekly reports to the Southwest Regional
Administrator (Regional Administrator), NMFS, including a summary of
the previous week's monitoring activities and an estimate of the number
of harbor seals that may have been disturbed as a result of seismic
retrofit construction activities. These reports will provide dates,
time, tidal height, maximum number of harbor seals ashore, number of
adults, sub-adults and pups, number of females/males, number of
redcoats, and any observed disturbances. A description of retrofit
activities at the time of observation and any sound pressure levels
measurements made at the haulout will also be provided. A draft interim
report must be submitted to NMFS by April 30, 2001.
Because seismic retrofit activities are expected to continue beyond
the date of expiration of this IHA (presumably under a new IHA), a
draft final report must be submitted to the Regional Administrator
within 90 days after the expiration of this IHA. A final report must be
submitted to the Regional Administrator within 30 days after receiving
comments from the Regional Administrator on the draft final report. If
no comments are received from NMFS, the draft final report will be
considered to be the final report.
CALTRANS will provide NMFS with a follow-up report on the post-
construction monitoring activities within 18 months of project
completion in order to evaluate whether haul-out patterns are similar
to the pre-retrofit haul-out patterns at Castro Rocks.
National Environmental Policy Act
NMFS prepared an EA in 1997 that concluded that the impacts of
CALTRANS' seismic retrofit construction of the Bridge will not have a
significant impact on the human environment. A copy of that EA, which
includes the Finding of No Significant Impact is available upon request
(see ADDRESSES).
Conclusions
NMFS has determined that the short-term impact of the seismic
retrofit construction of the Bridge, as described in this document,
should result, at worst, in the temporary modification in behavior by
harbor seals and, possibly, by some California sea lions. While
behavioral modifications, including temporarily vacating the haul-out,
may be made by these species to avoid the resultant visual and acoustic
disturbance, this action is expected to have a negligible impact on the
animals. In addition, no take by injury and/or death is anticipated,
and harassment takes will be at the lowest level practicable due to
incorporation of the mitigation measures mentioned above.
Since NMFS is assured that the taking will not result in more than
the incidental harassment (as defined by the MMPA) of small numbers of
Pacific harbor seals and, possibly, of California sea lions, would not
have an unmitigable adverse impact on the availability of these stocks
for subsistence uses, and would result in the least practicable impact
on the stocks, NMFS has determined that the requirements of section
101(a)(5)(D) have been met and the authorization can be issued.
Authorization
For the above reasons, NMFS has issued an IHA for a 1-year period
beginning September 1, 2000, for the incidental harassment of harbor
seals and California sea lions by the seismic retrofit of the Richmond-
San Rafael Bridge, San Francisco Bay, California, provided the above
mentioned mitigation, monitoring and reporting requirements mentioned
earlier are incorporated.
[[Page 2381]]
Dated: January 8, 2000.
Donald R. Knowles,
Director, Office of Protected Resources, National Marine Fisheries
Service.
[FR Doc. 00-953 Filed 1-13-00; 8:45 am]
BILLING CODE 3510-22-F