[Federal Register Volume 62, Number 246 (Tuesday, December 23, 1997)]
[Notices]
[Pages 67045-67051]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-33387]
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DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
[I.D. 080897A]
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.
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) 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, San
Francisco Bay, CA (the Bridge) has been issued to the California
Department of Transportation (Caltrans) for a period of 1 year.
DATES: This authorization is effective from December 16, 1997, through
December 15, 1998.
ADDRESSES: The application, authorization, and environmental assessment
(EA), and a list of references used in this document are available by
writing to the following offices: Marine Mammal Division, Office of
Protected Resources, NMFS, 1315 East-West Highway, Silver Spring, MD
20910-3225, or the Southwest Region, NMFS, 501 West Ocean Blvd., Suite
4200, Long Beach, CA 90802, or by telephoning one of the following
contacts.
FOR FURTHER INFORMATION CONTACT: Kenneth R. Hollingshead, Office of
Protected Resources, NMFS, (301) 713-2055, or Irma Lagomarsino,
Southwest Regional Office, NMFS, (562) 980-4016.
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 (Secretary) 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, 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), will not have an
unmitigable adverse impact on the availability of the species or
stock(s) for subsistence uses, and the permissible methods of taking
and requirements pertaining to the monitoring and reporting of such
taking 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 provides 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 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
[[Page 67046]]
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) provides 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 July 7, 1997, NMFS received an application from Caltrans,
requesting an authorization 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. Accordingly, NMFS published a
notice in the Federal Register on September 3, 1997 (62 FR 46480),
requesting comments on NMFS' proposal to authorize Caltrans, under
section 101(a)(5)(D) of the MMPA, to take, by harassment, small numbers
of marine mammals incidental to seismic retrofit construction of the
Bridge.
The Bridge will be seismically retrofitted to withstand a future
severe earthquake. Construction is scheduled to begin in December 1997
and extend through December 2001. A detailed description of the work
planned is contained in Caltrans' 1996 Final Natural Environmental
Study/Biological Assessment for the Richmond-San Rafael Bridge Seismic
Retrofit Project. 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. The construction duration for the seismic retrofit
of foundation and towers on Piers 52 through 57 will be approximately 7
to 8 months. Because of work restrictions and mitigation measures, the
seismic retrofit construction in this area is expected to be completed
within two authorized work periods.
As the seismic retrofit construction between Piers 52 and 57 may
potentially result in disturbance of pinnipeds at Castro Rocks, an MMPA
authorization is warranted.
Comments and responses
A notice of receipt of the application and proposed authorization
was published on September 3, 1997 (62 FR 46480), and a 30-day public
comment period was provided on the application and proposed
authorization. In addition a press release was issued on September 10,
1997, and a public notice was published in a newspaper of general
circulation in the San Francisco Bay area. During the comment period,
comments were received from the Marine Mammal Commission (MMC),
Caltrans, and the California Law Project (CLP). Information on the
activity and authorization request that are not subject to reviewer
comments can be found in the proposed authorization notice and is not
repeated here.
Comments on MMPA Authorizations
Comment 1: CLP was of the opinion that the purpose and intent of
the IHA provision in section 101(a)(5)(D) of the MMPA is to allow
incidental marine mammal taking when the harassment will be ``short-
term and non-lethal.'' Because neither the Caltrans application nor the
EA made clear that the seismic retrofit project would have ``short-term
and non-lethal'' impacts to harbor seals, a section 101(a)(5)(D)
authorization under the MMPA would be inappropriate. CLP notes that the
project would extend beyond the 1-year time limit specified in section
101(a)(5)(D) and that subsequent renewals would be necessary. CLP notes
that Congress intended that projects of this length (up to 5
consecutive years) be permitted under the more protective provisions of
section 101(a)(5)(A).
Response: NMFS does not agree. When implementing section
101(a)(5)(D) in 1994, the House of Representatives noted: ``It is not
the Committee's intent to weaken any of the existing standards which
protect marine mammals and their habitats from incidental takes under
this section. However, the Committee recognizes that the regulatory
agencies must be afforded some procedural flexibility in order to
streamline the review of authorizations under this section.'' (H. Rept.
103-439, 103rd Congress, 2nd Sess., pp. 29, 30.) Provided the taking is
not expected to result in the serious injury or mortality of marine
mammals, a section 101(a)(5)(D) authorization is appropriate. That
issue is addressed below.
The U.S. Congress did not intend to limit incidental harassment
authorizations to activities that would take place in a single year or
less, only that the authorization would be valid for no more than 1
year. After that period, the activity participants could reapply. This
interpretation of the statute is supported by the statement ``The
Committee notes that, in some instances, a request will be made for an
authorization identical to one issued in the previous year. In such
circumstances, the Committee expects the Secretary to act expeditiously
in complying with the notice and comment requirements.'' (H. Rept. 103-
439, 103rd Congress, 2nd Sess., p. 29.)
Comment 2: CLP believes that without more protective mitigation,
injury or mortality of harbor seals could occur, and, therefore, the
use of an IHA may be inappropriate because no serious injury or death
would be authorized.
Response: NMFS disagrees that the issuance of an IHA under section
101(a)(5)(D) is inappropriate for this project. In the IHA, NMFS is
requiring Caltrans to expand several of its mitigation measures to
further decrease the potential for serious injury or mortality of
harbor seals during construction activities (see Comments on Mitigation
and Mitigation Measures). Moreover, the monitoring and reporting
programs have been greatly expanded (see Monitoring and Reporting
sections). NMFS expects the mitigation requirements of the IHA to
preclude harbor seals from serious injury or mortality and will result
in the least practicable impact to harbor seals from construction
activities. Comment 3: CLP recommends that NMFS require that Bridge
retrofit construction be halted if any ``harmful disturbance'' occurs
during the pupping or molting season.
Response: NMFS will not be requiring Caltrans to stop work if
certain threshold seal disturbances are observed because certain
construction operations cannot be stopped in progress without
jeopardizing the structural integrity of the Bridge and NMFS does not
expect incidental harassment of harbor seals from construction
activities to have more than a negligible impact on the harbor seal
population. Nevertheless, if any unauthorized marine mammal taking
(serious injury or mortality) occurs as a result of seismic retrofit
construction activities, Caltrans will be subject to the penalties of
the MMPA. NMFS will, however, reevaluate the appropriateness of the IHA
before Caltrans reapplies for a new IHA next year, based on required
reports (see Reporting section).
Comment 4: CLP concludes that harbor seals that inhabit San
Francisco Bay (SFB) are a ``population stock'' under the MMPA and
believes NMFS
[[Page 67047]]
should consider the impacts of the retrofit construction relative to
the SFB population stock.
Response: NMFS disagrees that the best available information
indicates that harbor seals that inhabit SFB are a ``population stock''
under the MMPA. Studies have shown that adult harbor seals in SFB have
a high degree of site fidelity as indicated by (1) high occurrence of
red pelaged seals in SFB; (2) organochlorine containment levels are
higher in harbor seals that haul-out in SFB; and (3) limited movement
of adult harbor seals tagged in SFB to nearby coastal areas.
Nevertheless, data are not available that demonstrate that harbor seal
pups born at haul-out sites in SFB return to breed and pup at the same
site where they were born. Thus, at this time, scientists do not know
whether pups born in SFB show the same degree of site fidelity as
adults or whether they utilize other haul-outs either within SFB or in
nearby coastal areas when they mature. Studies of adult harbor seals
tagged in SFB indicate that the level of movement to nearby coastal
areas (20 percent) (Kopec and Harvey 1995, Harvey and Torok 1994) would
be sufficient to preclude isolation if those seals were breeding with
seals found along the coast (Harvey, J., Moss Landing Marine
Laboratory, pers. commun., November 1997). Moreover, genetic studies
have not been conducted to determine whether seals in SFB have unique
genetic variation or genotypes. In contrast, NMFS has separated harbor
seals within inland waters of Washington as a population stock under
the MMPA based on (1) extremely low mixing with coastal harbor seals,
(2) pollutant loads, (3) fishery interactions, (4) existence of unique
haplotypes in inland Washington harbor seals, and (5) differences in
mean pupping dates. The best available information does not demonstrate
that harbor seals in SFB are a unique biological population (Harvey,
J., pers. commun., 1997; Allen, S., NPS, pers. commun., November 1997;
Hanan, D., CDFG, pers. commun., November 1997). For these reasons, NMFS
does not consider harbor seals in SFB to be a population stock under
the MMPA.
Under section 117 of the MMPA, NMFS is required to prepare stock
assessment reports (SARs) for every marine mammal stock that occurs in
U.S. waters. NMFS has convened two expert working groups (NMFS and Non-
NMFS scientists/managers) to draft guidelines for preparing SARs
(Barlow et al. 1995, Wade and Angliss 1997). Furthermore, SARs are
available for public review and comment and are reviewed by regional
scientific review groups (all non-NMFS scientists). Using these
guidelines and in consultation with the Pacific Scientific Review
Group, NMFS published a SAR that considers harbor seals that occur in
California as a separate population stock (Barlow et al. 1995). This
SAR reports a population abundance estimate of 34,554 harbor seals.
This stock of harbor seals is not considered ``depleted'' or
``strategic'' under the MMPA or listed as an endangered or threatened
species under the Endangered Species Act. For these reasons, NMFS is
considering the impact of seismic retrofit construction of the Bridge
on the California harbor seal stock.
Harbor Seal Concerns
Comment 5: CLP believes the Federal Register notice's statement
``evidence to date has not indicated that anthropogenic disturbances
have resulted in increased mortality to harbor seals'' in 62 FR 46480
(September 3, 1997), is incorrect as several studies document this. The
Boles and Stewart (1980) study merely describes behavior patterns
consistent with one found with Bay harbor seals and does not support a
finding that human disturbance does not result in serious harm or
mortality.
Response: In retrospect, NMFS believes the statement made was too
broad and it should reflect that, to date, studies have not indicated
that airborne anthropogenic noise has resulted in increased harbor seal
mortality. NMFS would be interested in specific harbor seal studies
that indicate otherwise. It should be recognized that most of this
information is from studies on the impact of noise from rocket launches
and sonic booms on harbor seals and sea lions in the California Channel
Islands and, in the past, has been mostly qualitative. Upcoming studies
have been redesigned to be more quantitative.
Comment 6: CLP states that there is no evidence that seals will
adapt to construction, and harbor seals have abandoned sites in SFB.
Harbor seals hauling-out in areas of frequent but non-threatening
disturbances show a relatively higher tolerance for such events when
compared with more isolated areas where disturbance is rare.
Observations of harbor seals at Castro Rocks found that seals flush
easily in response to human disturbance.
Response: NMFS agrees that there is no scientific evidence that
demonstrates harbor seals will acclimate to disturbance from
construction activities. NMFS also believes that seals are likely to
acclimate to activities they perceive as non-threatening. Although
harbor seal colonies have abandoned haul-out sites in SFB, colonies
also have acclimated to various levels of human activity. In
particular, despite the regular exposure to traffic noises from the
Bridge, vessel traffic from commercial activities at the Chevron Long
Wharf, and vessel traffic from recreational boating and commercial
shipping in the area, harbor seals continue to haul-out, pup, breed,
and molt at Castro Rocks. For these reasons, NMFS believes that harbor
seals at Castro Rocks may acclimate to certain seismic retrofit
construction activities if they perceive these activities as non-
threatening.
Comment 7: CLP believes that seal counts by Caltrans personnel
during June 1994/1996 misrepresent the number of pups using Castro
Rocks.
Response: Presentation of the seal counts by Caltrans personnel
during June 1994 and 1996 was not intended to establish the period in
which pups are born at Castro Rocks. The best available information
indicates that in SFB harbor seal pups are first observed in mid-March,
peak numbers of pups are observed in early May, and by the first week
of June, the majority of the pups are weaned (Kopec, D., Romberg
Tiburon Centers, pers. commun., November 1997; (i.e., Kopec 1997)).
Comment 8: The statement in the Federal Register notice (62 FR
46480, September 3, 1997) that ``haul-out groups are temporary,
unstable aggregations'' does not accurately represent the current
knowledge of harbor seal population dynamics. Seals in SFB show strong
site fidelity.
Response: The statement is from Sullivan (1982) and is not refuted
by Kopec and Harvey (1995). However, because harbor seals show strong
site fidelity (Kopec and Harvey 1995, Stewart and Yochem 1994), the
statement may be misleading.
Comment 9: The finding of Bowles and Stewart (1980) referenced in
the Federal Register notice (62 FR 46480) that ``harbor seals tendency
to flee...decreased during the pupping season,'' does not support the
claim that young seals are protected from `` ...the startle response of
the herd.''
Response: Reviewing the referenced source, NMFS has determined that
there is no evidence that harbor seals are less sensitive to
disturbance during the pupping season than at other times. This agrees
with Kopec's observations (Kopec 1997). See Mitigation Measures.
Comments on Mitigation Measures
Comment 10: CLP had several concerns regarding NMFS' conclusions on
the impact of disturbance on molting harbor seals and the
appropriateness of Caltrans' proposed work closure period
[[Page 67048]]
(February 1-June 30). For example, CLP believes there is no scientific
evidence to support the conclusion in the Federal Register notice (62
FR 46480, September 3, 1997) that harbor seals have evolved adaptive
mechanisms to deal with natural disturbance from predators and seabirds
during the molt. CLP states this is supported by the behavior of harbor
seals to haul out in very isolated locations precisely to avoid
disturbance, and it is not factual to suggest that seabirds cause seals
to flush into the water. Existing as they do at the top of the food
web, CLP states, harbor seals using Castro Rocks have no natural
predators. CLP states that the very sensitive molting season of seals
using Castro Rocks extends to at least early or mid-August. Caltrans'
application and the EA failed to adequately assess the project's
impacts to molting seals during July and August. For these reasons, CLP
recommended that the Closure Period be extended to include the entire
molt.
Response: The process of molting is an important and energetically
demanding part of a seal's annual cycle (Leatherwood et al. 1992).
While on land, harbor seals bask in the sun to warm their body surface
and promote flow of blood to the skin which is essential for new hair
growth. While little is known about the effect of disturbance on
molting harbor seals, energetic costs are probably higher for seals
that spend more time in the water during the molt since a seal's
metabolic rate increases in the water (DeLong, R., NMFS, pers. commun.,
November 1997). Nevertheless, NMFS believes that it is likely that
harbor seals have evolved adaptive mechanisms to deal with exposure to
the water during the molt for the following reasons. First, on some
harbor seal haul-outs during the molting season seals must enter the
water once or even twice a day due to tidal fluctuations limiting
access to the haul-out. Second, since harbor seals lose hair in patches
during the molt, they are never completely hairless and would not be as
vulnerable to heat loss in the water during this period compared to
other seals (e.g., elephant seals) that lose their all their hair at
one time. Finally, due to the large amount of time hauled-out harbor
seals allocate to scanning their environment, it is likely that
terrestrial predation was an important selection pressure during the
early evolution of harbor seal behavior (Da Silva and Terhune 1988) and
could be the reason why hauled-out harbor seals appear to be so
sensitive to disturbance. Disturbance would not have been isolated to
only non-molting seasons and thus, harbor seals most likely evolved
mechanisms to tolerate exposure to water during the molt. Some harbor
seal colonies in California continue to be subject to disturbance from
wildlife such as seabirds (Hanan, D. pers. commun., 1997) and human
activities. If the levels of harbor seal disturbance during the molt
are relatively high, seals are likely to utilize other local haul-out
sites during the molt (DeLong, R., pers. commun. 1997; Hanan, D., pers.
commun. 1997; Harvey, J., pers. commun. 1997). Hanan (1996) found that
although harbor seals tagged at an isolated southern California haul-
out tended to exhibit site-fidelity during the molt, some seals were
observed molting at other nearby haul-outs.
The primary objectives of the Kopec and Harvey (1995) study was to
determine the population dynamic and movements, investigate the
concentration of pollutants, and assess the health of harbor seals
within and near SFB. Although the number of molting seals was recorded
during most field observations, molt observations were incidental to
Kopec and Harvey's (1995) primary census counts (Kopec 1997). Thus,
although Kopec and Harvey (1995) refer to the ``reproductive/molting''
period at Castro Rocks as occurring between March-July, no data are
presented to support this conclusion. Moreover, they report that ``In
San Francisco Bay, pupping occurs from March to May, and molt in June.
This corresponds with the greatest number of harbor seals counted in *
* *Castro Rocks.'' For these reasons, NMFS concluded that the proposed
Closure Period (February 1-June 30) would encompass all of the pupping
and breeding season, and nearly the entire harbor seal molting season
at Castro Rocks.
Recently available unpublished information indicates that the peak
number of actively molting harbor seals occurs in early July at Castro
Rocks (Kopec 1997), which coincides with the peak of the molt for
harbor seals near and within SFB (S. Allen, pers. commun., 1997). By
early August, only five to seven percent of the seals are actively
molting at Castro Rocks (Kopec 1997).
Based on new information on harbor seals molting at Castro Rocks,
NMFS has expanded the Closure Period to include the entire month of
July (see Mitigation Measures). The modified Closure Period (February
15 - July 31) is designed to encompass the entire harbor seal pupping
and breeding seasons and nearly the entire molting season at Castro
Rocks (see Mitigation Measures). This represents a period of five and
one-half months in which no work may be conducted on the substructure,
towers, or superstructure between Piers 52 and 57, inclusive (please
see related comment 11 below). Any harbor seals that are still molting
when work begins after the Closure Period are likely to utilize other
SFB haul-out sites if they are substantially disturbed by construction
activities in the area (DeLong, R., pers. commun., 1997; Hanan, D.,
pers. commun. 1997; Harvey, J., pers. commun. 1997). Expanding the
Closure Period further would result in another season of work near
Castro Rocks and in prolonged disturbance to seals utilizing Castro
Rocks. The Closure Period could be expanded during the second year of
the project if monitoring results indicate that impacts may be greater
than negligible.
Comment 11: CLP believes that the proposed seasonal restrictions
are not sufficient to protect seals during the earlier pupping and
nursing season because work will be allowed to continue on the
superstructure and could negatively impact seals during the spring
pupping and summer molting seasons. Furthermore, CLP notes that the IHA
notice contradicts the EA's superstructure seasonal closure period. For
these reasons, CLP recommends that the work closure area include a
prohibition on superstructure work between Piers 52 and 57.
Response: NMFS agrees and, as mentioned in comment 10 above, has
modified the Closure Period to include all retrofit construction
activities on the substructure (e.g., piers), towers, and
superstructure between Pier's 52 and 57, inclusive (see Mitigation
Measures). Since the Closure Period has been expanded to include nearly
the entire molting season (see above), NMFS has modified the Closure
Period to begin on February 15, instead of February 1. In SFB, harbor
seal pups are first observed in mid-March, peak numbers of pups are
observed in early May, and, by the first week of June, all pups are
weaned (Kopec and Harvey 1995). Thus, the Closure Period will include
the entire pupping season at Castro Rocks and a substantial pre-pupping
period when females are moving into pupping areas. As mentioned
previously, imposing a 6-month Work Closure Period (i.e., February 1-
July 31) would likely result in another season of work near Castro
Rocks and in prolonged disturbance to seals at Castro Rocks.
Comment 12: The CLP believes that the size of Caltrans' proposed
exclusion zone around Castro Rocks is arbitrary and inconsistent with
both the existing scientific literature or reported reactions and
actual observations of disturbance behavior at Castro Rocks. For these
[[Page 67049]]
reasons, CLP recommends that the exclusion zone be expanded to a
minimum of 200 m (656 ft) on all sides of Castro Rocks and that the
zone be expanded if monitoring indicates seals are adversely effected
by boats traveling outside the zone boundaries.
Response: The purpose of the exclusion zone is to establish an area
around Castro Rocks in which retrofit construction activity will be
prohibited during the pupping, breeding, and the majority of the
molting season (the Work Closure Period) to minimize the impacts to
seals during the sensitive periods of their life cycle. Caltrans
originally proposed that the exclusion zone be located between the
Bridge center line, between Piers 52 and 57, and extend to 200 ft (61
m) south of the most southwestern portion of Castro Rocks.
Reactions of harbor seals to disturbance depends upon the distance
of the activity to the seal, type of the activity (e.g., boat traffic,
aircraft overflights, loud sounds, etc.), phase of seal life cycle
(e.g., pupping season, non-pupping season), and the history of
disturbance the colony has previously experienced. Depending on the
activity, a wide range of seal ``reaction distances'' have been
reported in the literature (e.g., 30-1,800 m (98-5900 ft)). In an
adjacent SFB estuary, Bolinas Lagoon, 81 percent of disturbances
(boats, hikers, dogs) were within 100 and 200 m (328 and 656 ft) of a
harbor seal haul-out (Swift and Morgan 1993). Although seals at Castro
Rocks have habituated to background traffic noise from the Bridge, they
respond to unusual noises, such as hammering, truck horns, back-up
signal beeps, work boats, and other human activity on the Bridge
(Kopec, D., letter to CLP, dated October 3, 1997).
NMFS agrees that the exclusion zone should be expanded to further
minimize the impact of seismic retrofit construction activities during
the Closure Period. For this reason, NMFS is requiring Caltrans to
greatly expand the northern boundary of the exclusion zone. For
example, the northern boundary has been extended from the Bridge center
line to 250 ft (76.2 m) north of the most northern tip of Castro Rocks
(approximately 200 ft (61 m)) north of the Bridge center line). An
expansion of this boundary further north is impractical due to the need
for a safe navigation corridor north of the Bridge for work vessel
access to construction staging areas near the east end of the Bridge.
The southern boundary of the exclusion zone will be 250 ft (76.2 m)
south of the southern tip of Castro Rocks. Due to the location of this
boundary relative to the Bridge (600 ft/183 m), it is unlikely that the
unrestricted area further south would be practicable for use during
construction (e.g., corridor to a staging area on the south side of the
Bridge). Any further expansion of the southern boundary would encroach
onto waters outside Caltran's control (e.g., right-of-way) and could
affect Chevron's oil pier operations further south. The eastern
boundary will be 300 ft (91.4 m) east of the eastern tip of Castro
Rocks, and the western boundary will be 300 ft (91.4 m) west of the
western tip of Castro Rocks. Similarly, any further expansion of these
boundaries would encroach onto waters outside Caltrans' control.
Caltrans will minimize vessel traffic in the exclusion zone when
conducting construction activities during the Work Period. For these
reasons, NMFS believes these boundaries will have the least practicable
impact on the California harbor seal population.
Comment 13: Caltrans recommends that the prohibition on pile
installation and the limitation on maximum noise levels to 86 DBA re 20
uPa at 50 m between 7 p.m. and 7 a.m. be modified to the hours between
9 p.m. and 7 a.m.. Caltrans states that this is necessary to allow for
the Bridge retrofit contractor to use two working shifts instead of one
shift. Caltrans also recommends removing the 24-hr construction noise
limitation near Castro Rocks during the pupping/molting restriction
period because no work will be conducted between Piers 52 and 57,
inclusive on the substructure, towers, or superstructure during this
period.
Response: NMFS agrees. Although the night time restriction for pile
installation and maximum noise levels was originally developed by
Caltrans to minimize human residential noise disturbance, NMFS is also
requiring night time restrictions because it believes that it could
protect seals at Castro Rocks if they change their hauling-out patterns
from daytime to night time. NMFS has modified the time period for this
requirement from 7 p.m.-7 a.m. to 9 p.m.-7 a.m. because restricting
this mitigation measure further would allow only one work shift, would
likely result in another season of work near Castro Rocks, and thus,
would result in prolonged disturbance to seals utilizing Castro Rocks
(see Mitigation Measures). NMFS also agrees that the 24-hr. noise
limitation near Castro Rocks is no longer necessary due to all work
ceasing on the substructure, towers, and superstructure on Pier's 52-
57, inclusive, during the pupping, breeding, and majority of the
molting season.
Comment 14: CLP recommends that NMFS require Caltrans to conduct
certain offsite mitigation that will enhance the protection of
alternative haul-out sites, many of which are under pressure from human
disturbance. Such mitigation might take the form of education signs or
posters at haul-outs and other locations to reduce potential for human
disturbance.
Response: NMFS believes that the mitigation measures imposed under
the IHA will effectively mitigate the activity to the lowest level
practicable and still allow the project to continue near to schedule.
As a result, additional off-site mitigation measures are unwarranted.
NMFS believes that mitigation banking is appropriate only under those
circumstances when the impact cannot be mitigated onsite.
Monitoring and Reporting Concerns
Comment 15: CLP believes that the proposed monitoring plan is
inadequate and should be replaced by a comprehensive, quantitative
monitoring program. CLP recommends that the IHA establish upper limits
of disturbance beyond which the source construction activity is
curtailed. CLP believes the IHA should require continuous site
monitoring and immediate reporting that, when triggered, will
temporarily halt construction activity near Castro Rocks and will
impose additional mitigation.
Response: NMFS has significantly expanded the requirements of the
monitoring program that must be implemented by Caltrans under its IHA
(see Monitoring). For example, the monitoring program includes pre-
construction monitoring of Castro Rocks (e.g., baseline information)
and frequent monitoring each week within the Work Period to document
the effects of construction activities on harbor seals at Castro Rocks.
The monitoring of at least one alternative haul-out site in SFB is also
required to evaluate whether harbor seals at Castro Rocks could be
hauling out at other sites in SFB as a result of construction.
Monitoring will also occur during the Closure Period to evaluate
whether construction activities are disturbing the seals during their
pupping, breeding and molting periods. Moreover, night time censussing
of harbor seals will occur during the Closure Period and Work Period at
Castro Rocks to evaluate whether harbor seal haul-out behavior may be
affected by construction activities during these periods. NMFS believes
this improved monitoring program will be sufficient to collect
appropriate data to adequately evaluate the biological impact of
[[Page 67050]]
construction activities on Castro Rocks harbor seals.
Comment 16: CLP suggested that enhanced protection and monitoring
of other, limited, haul-out sites in SFB are critical to monitoring
measures and must be implemented under National Environmental Policy
Act (NEPA) and MMPA.
Response: In the IHA, NMFS is requiring Caltrans to simultaneously
monitor at least one other harbor seal haul-out site in SFB to document
potential changes in harbor seal population dynamics in SFB from
seismic retrofit construction disturbance of seals at Castro Rocks.
NEPA Concerns
Comment 17: CLP states that NMFS must comply with NEPA, which is
the statute requires the preparation of an environmental impact
statement (EIS) where a Federal project may have a significant adverse
impact on the environment.
Response: NMFS is issuing the IHA in compliance with NEPA. After
assessing the effects of the Bridge project (undertaken with the
mitigation measures) on marine mammals in an EA, NMFS found that
issuance of the IHA will not have a significant effect on the human
environment. Accordingly, an EIS was not prepared.
For the Bridge project as a whole, the lead Federal agency is the
Federal Highway Administration (FHA). On August 15, 1997, the FHA
determined that the retrofit project is categorically excluded from
NEPA. In that determination, the FHA stated that the retrofit project
does not have a significant effect on the human environment.
In addition, Caltrans determined that the retrofit project is
statutorily exempt from the California Environmental Quality Act (CEQA)
under section 180.2 of the Streets and Highways Code and section
2180(b)(4) of the Public Resources Code.
Comment 18: CLP states that CLP believes that an EIS must be
prepared, unless the project is ``fully mitigated,'' to avoid
``devastating impacts'' (e.g., abandonment) on the future viability of
Castro Rocks as a harbor seal haul-out site and adversely affecting the
population stock that relies on Castro Rocks.
Response: NMFS does not agree that abandonment of Castro Rocks as a
haul-out site is likely from the seismic retrofit construction of the
Bridge, provided Caltrans undertakes the mitigation measures required
in the IHA. NMFS expects that the short-term impact of construction to
have a temporary mod-ification in behavior by harbor seals at Castro
Rocks and possibly by some California sea lions. At worst, disturbance
from construction activities is expected to cause the harbor seals to
haul-out at night at Castro Rocks (Kopec, D., letter to CLP, dated
October 3, 1997), or to utilize alternative haul-out sites in the SFB
for a short period (Harvey, J., 1997, pers. commun.). Therefore, NMFS
expects the impacts from the seismic retrofit construction of the
Bridge to have no more than a negligible impact on the California
harbor seal population and does not expect harbor seals to permanently
abandon Castro Rocks as a rookery or haul-out. With the mitigation
measures NMFS is requiring, the Bridge project is expected to result in
minimal disturbance to harbor seals at Castro Rocks.
Mitigation Measures
To limit incidental harassment to the lowest practicable level,
NMFS will require Caltrans to implement the following mitigation
measures. First, Caltrans must cease seismic retrofit construction work
from February 15 to July 31 on the Bridge substructure, towers, and
superstructure between Pier's 52 and 57, inclusive (Closure Period).
Seismic retrofit work may occur from August 1 to February 14 on the
Bridge substructure, towers, and superstructure between Pier's 52 and
57, inclusive (Work Period). Second, no water craft associated with
construction activities will be deployed during the year within the
``exclusion zone'' except when construction equipment is required for
seismic retrofit construction between Piers 52 and 57, inclusive, and
within the Work Period. Vessel traffic will be minimized in the
exclusion zone when construction activities are occurring during the
Work Period. The boundary of the exclusion zone is rectangular in shape
(1700 ft by 800 ft (518.2 m by 244 m)) and completely encloses Castro
Rocks and Pier's 52-57, inclusive. The northern boundary of exclusion
zone will be located 250 ft (76.2 m) from the most northern tip of
Castro Rocks, and the southern boundary will be located 250 ft (76.2 m)
from the most southern tip of Castro Rocks. The eastern boundary will
be located 300 ft (91.4 m) from the most eastern tip of Castro Rocks,
and the western boundary will be located 300 ft (91.4 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. Lastly, between 9 p.m. and 7 a.m., no piles
may be installed on the Bridge, and construction noise may not exceed
86 DBA re 20 uPa at 50 ft (15 m).
Summary of 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 will monitor at least one additional harbor seal haul-out
within SFB 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 - February 14) and the Closure Period Phase (February 15 -
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 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 Pier's 52 and 57, inclusive, the
monitor(s) will conduct baseline observations of seal behavior once a
day for a period of five 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 at the
alternative San Francisco Bay harbor seal haul-out at least 3 days/week
(Work Period) and 2 days/week (Closure Period), during a low tide.
In addition, NMFS proposes to require under a second authorization
that, immediately following the completion of the seismic retrofit
construction of the Bridge, the monitor(s) will conduct observations of
seal behavior 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, the
monitor will conduct an additional harbor seal census after midnight.
[[Page 67051]]
Reporting
Caltrans will provide weekly reports to the Southwest Regional
Administer, 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 and sub-adults, 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 level measurements made at the haulout will also be
provided.
A draft interim report must be submitted to the Southwest Regional
Administrator on August 1, 1998. A draft final report must be submitted
to the Southwest Regional Administrator within 90 days after the
expiration of Caltrans Incidental Harassment Authorization. A final
report must be submitted to the Southwest Regional Administrator within
30 days after receiving comments from the Regional Administrator on the
draft final report.
NEPA
NMFS has prepared an EA that concludes that the impacts of
Caltrans' seismic retrofit construction of the Bridge will not have a
significant impact on the human environment. A copy of the EA 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 above, will 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 unmitigatable 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.
For the above reasons, NMFS has issued an IHA for a 1-year period
beginning on the date noted above (see EFFECTIVE DATES) 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 monitoring and reporting
requirements are incorporated.
Dated: December 16, 1997.
Hilda Diaz-Soltero,
Director, Office of Protected Resources, National Marine Fisheries
Service.
[FR Doc. 97-33387 Filed 12-22-97; 8:45 am]
BILLING CODE 3510-22-F
