Small Takes of Marine Mammals Incidental to Specified Activities; Seismic Retrofit of the Richmond-San Rafael Bridge, San Francisco Bay, CA

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

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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