Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to Demolition and Reuse of the Original East Span of the San Francisco-Oakland Bay Bridge, 15795-15820 [2018-07573]
Download as PDF
sradovich on DSK3GMQ082PROD with NOTICES
Federal Register / Vol. 83, No. 71 / Thursday, April 12, 2018 / Notices
observer coverage, this would equate to
roughly 30–35 EFP trips.
Vessels participating in this EFP
would use EM in lieu of human ASMs,
and in addition to Northeast Fishery
Observer Program (NEFOP) observers,
on groundfish trips selected for observer
coverage. Vessels would adhere to a
vessel-specific Vessel Monitoring Plan
(VMP) detailing at-sea catch handling
protocols. An EM service provider
would review 100 percent of the video
footage. The provider would also
produce an EM summary report
identifying, counting, and generating
weight estimates for all groundfish
discards, which it would submit to the
NMFS Greater Atlantic Fisheries
Regional Office. These data would be
used for catch accounting purposes on
trips selected for ASM coverage. EM
data would not be used for catch
accounting in place of observer data on
NEFOP trips, but the information
generated would facilitate comparisons
between cameras and human observers.
The Northeast Fisheries Science Center
would conduct a secondary review of
the EM summary reports for a subset of
EFP trips.
Under this EFP, vessels would be
exempt from their sector’s monitoring
program requirement only, and all other
standard sector reporting and
monitoring requirements would still
apply, such as using dealer-reported
landings and vessel trip reports. Vessels
would be assigned observer coverage at
the standard ASM coverage level of 15
percent, which is a combination of
NEFOP and ASM coverage. All catch of
allocated groundfish stocks would be
deducted from the appropriate sector’s
allocation. Legal-sized regulated
groundfish would be retained and
landed, as required by the Northeast
Multispecies Fishery Management Plan.
Undersized groundfish would be
handled according to the VMP
guidelines in view of cameras and
returned to the sea as quickly as
possible. All other species would be
handled per normal commercial fishing
operations. No legal-size regulated
groundfish would be discarded, unless
otherwise permitted through regulatory
exemptions granted to the participating
vessel’s sector.
If approved, the applicant may
request minor modifications and
extensions to the EFP throughout the
year. EFP modifications and extensions
may be granted without further notice if
they are deemed essential to facilitate
completion of the proposed research
and have minimal impacts that do not
change the scope or impact of the
initially approved EFP request. Any
fishing activity conducted outside the
VerDate Sep<11>2014
19:20 Apr 11, 2018
Jkt 244001
scope of the exempted fishing activity
would be prohibited.
Authority: 16 U.S.C. 1801 et seq.
Dated: April 9, 2018.
Jennifer M. Wallace,
Acting Director, Office of Sustaianble
Fisheries, National Marine Fisheries Service.
[FR Doc. 2018–07595 Filed 4–11–18; 8:45 am]
BILLING CODE 3510–22–P
DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric
Administration
RIN 0648–XG059
Takes of Marine Mammals Incidental to
Specified Activities; Taking Marine
Mammals Incidental to Demolition and
Reuse of the Original East Span of the
San Francisco-Oakland Bay Bridge
National Marine Fisheries
Service (NMFS), National Oceanic and
Atmospheric Administration (NOAA),
Commerce.
ACTION: Notice; proposed incidental
harassment authorization; request for
comments.
AGENCY:
NMFS has received a request
from the California Department of
Transportation (Caltrans) for
authorization to take marine mammals
during the dismantling and reuse of the
original East Span of the San FranciscoOakland Bay Bridge (SFOBB) in the San
Francisco Bay (SFB). Pursuant to the
Marine Mammal Protection Act
(MMPA), NMFS is requesting comments
on its proposal to issue an incidental
harassment authorization (IHA) to
incidentally take marine mammals
during the specified activities. NMFS
will consider public comments prior to
making any final decision on the
issuance of the requested MMPA
authorizations and agency responses
will be summarized in the final notice
of our decision.
DATES: Comments and information must
be received no later than May 14, 2018.
ADDRESSES: Comments should be
addressed to Jolie Harrison, Chief,
Permits and Conservation Division,
Office of Protected Resources, National
Marine Fisheries Service. Physical
comments should be sent to 1315 EastWest Highway, Silver Spring, MD 20910
and electronic comments should be sent
to ITP.Young@noaa.gov.
Instructions: NMFS is not responsible
for comments sent by any other method,
to any other address or individual, or
received after the end of the comment
period. Comments received
electronically, including all
SUMMARY:
PO 00000
Frm 00012
Fmt 4703
Sfmt 4703
15795
attachments, must not exceed a 25megabyte file size. Attachments to
electronic comments will be accepted in
Microsoft Word or Excel or Adobe PDF
file formats only. All comments
received are a part of the public record
and will generally be posted online at
https://www.fisheries.noaa.gov/node/
23111 without change. All personal
identifying information (e.g., name,
address) voluntarily submitted by the
commenter may be publicly accessible.
Do not submit confidential business
information or otherwise sensitive or
protected information.
FOR FURTHER INFORMATION CONTACT: Sara
Young, Office of Protected Resources,
NMFS, (301) 427–8401. Electronic
copies of the application and supporting
documents, as well as a list of the
references cited in this document, may
be obtained online at: https://
www.fisheries.noaa.gov/national/
marine-mammal-protection/incidentaltake-authorizations-constructionactivities. In case of problems accessing
these documents, please call the contact
listed above.
SUPPLEMENTARY INFORMATION:
Background
Sections 101(a)(5)(A) and (D) of the
MMPA (16 U.S.C. 1361 et seq.) direct
the Secretary of Commerce (as delegated
to NMFS) to allow, upon request, the
incidental, but not intentional, taking of
small numbers of marine mammals by
U.S. citizens who engage in a specified
activity (other than commercial fishing)
within a 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.
An authorization for incidental
takings shall be granted if NMFS finds
that the taking will have a negligible
impact on the species or stock(s), will
not have an unmitigable adverse impact
on the availability of the species or
stock(s) for subsistence uses (where
relevant), and if the permissible
methods of taking and requirements
pertaining to the mitigation, monitoring
and reporting of such takings are set
forth.
NMFS has defined ‘‘negligible
impact’’ in 50 CFR 216.103 as an impact
resulting from the specified activity that
cannot be reasonably expected to, and is
not reasonably likely to, adversely affect
the species or stock through effects on
annual rates of recruitment or survival.
The MMPA states that the term ‘‘take’’
means to harass, hunt, capture, kill or
attempt to harass, hunt, capture, or kill
any marine mammal.
E:\FR\FM\12APN1.SGM
12APN1
15796
Federal Register / Vol. 83, No. 71 / Thursday, April 12, 2018 / Notices
Except with respect to certain
activities not pertinent here, the MMPA
defines ‘‘harassment’’ as any act of
pursuit, torment, or annoyance which (i)
has the potential to injure a marine
mammal or marine mammal stock in the
wild (Level A harassment); or (ii) has
the potential to disturb a marine
mammal or marine mammal stock in the
wild by causing disruption of behavioral
patterns, including, but not limited to,
migration, breathing, nursing, breeding,
feeding, or sheltering (Level B
harassment).
sradovich on DSK3GMQ082PROD with NOTICES
National Environmental Policy Act
To comply with the National
Environmental Policy Act of 1969
(NEPA; 42 U.S.C. 4321 et seq.) and
NOAA Administrative Order (NAO)
216–6A, NMFS must review our
proposed action (i.e., the issuance of an
incidental harassment authorization)
with respect to potential impacts on the
human environment.
This action is consistent with
categories of activities identified in
Categorical Exclusion B4 (incidental
harassment authorizations with no
anticipated serious injury or mortality)
of the Companion Manual for NOAA
Administrative Order 216–6A, which do
not individually or cumulatively have
the potential for significant impacts on
the quality of the human environment
and for which we have not identified
any extraordinary circumstances that
would preclude this categorical
exclusion. Accordingly, NMFS has
preliminarily determined that the
issuance of the proposed IHA qualifies
to be categorically excluded from
further NEPA review.
We will review all comments
submitted in response to this notice
prior to concluding our NEPA process
or making a final decision on the IHA
request.
Summary of Request
On January 9, 2018, NMFS received a
request from Caltrans for an IHA to take
marine mammals incidental to the
demolition and reuse of the original East
Span of the SFOBB in San Francisco
Bay. Caltrans’ request is for take of
seven species of marine mammals, by
Level B harassment. Neither Caltrans
nor NMFS expects serious injury or
mortality to result from this activity
and, therefore, an IHA is appropriate.
NMFS previously issued several IHAs
to Caltrans for similar work, with the
most recent IHA issued in 2017 (82 FR
35510). Caltrans complied with all the
requirements (e.g., mitigation,
monitoring, and reporting) of the
previous IHAs and information
regarding their monitoring results may
VerDate Sep<11>2014
19:20 Apr 11, 2018
Jkt 244001
be found in the Effects of the Specified
Activity on Marine Mammals and their
Habitat and Estimated Take section.
This proposed IHA would cover one
year of a larger project for which
Caltrans obtained previous IHAs. The
larger project involves dismantling of
many piers of many remaining
structures from the original east span of
the bridge.
Description of Proposed Activity
Overview
Caltrans proposes to demolish and
reuse portions of the original East Span
of the SFOBB by mechanical
dismantling and by use of controlled
charges to implode two piers (Piers E19
and E20) into their open cellular
chambers below the mudline. Activities
associated with dismantling of the piers
may potentially result in incidental take
of marine mammals due to the use of
highly controlled charges to dismantle
the marine foundations of the piers. A
public access point will incorporate
existing piers (E21, E22, and E23) but
requires use of pile driving to finalize
the access structure. Pier E2 will also be
retained for public access
improvements, but does not require any
in-water work.
Several previous one-year IHAs have
been issued to Caltrans for pile driving/
removal and construction of the new
SFOBB East Span beginning in 2003.
NMFS has issued 11 IHAs to Caltrans
for the SFOBB Project. The first five
IHAs (2003, 2005, 2007, 2009, and 2011)
addressed potential impacts associated
with pile driving for the construction of
the new East Span of the SFOBB. IHAs
issued in 2013, 2014 and July 2015
addressed activities associated with
both constructing the new East Span
and dismantling the original East Span,
specifically addressing vibratory pile
driving, vibratory pile extraction/
removal, attenuated impact pile driving,
pile proof testing, and mechanical
dismantling of temporary and
permanent marine foundations. On
September 9, 2015, NMFS issued an
IHA to Caltrans for incidental take
associated with the demolition of Pier
E3 of the original SFOBB by highly
controlled explosives (80 FR 57584;
September 24, 2015). On September 30,
2016, NMFS issued an IHA authorizing
the incidental take of marine mammals
associated with both pile driving/
removal and controlled implosion of
Piers E4 and E5 (81 FR 67313). On July
13, 2017, NMFS issued an IHA to
Caltrans authorizing take of marine
mammals for additional dismantling the
original East Span of the SFOBB using
mechanical means as well as 5to 6
PO 00000
Frm 00013
Fmt 4703
Sfmt 4703
implosion events to dismantle 13 piers
(Piers E6–E18). This year of work will
include removal of Piers E19 and E20.
Dates and Duration
Vibratory pile driving for construction
of the Oakland Touchdown pedestrian
bridge (OTD) and OTD access trestle
may begin in June 2018. Impact piledriving activities will be restricted from
June 1 to November 30, to avoid peak
salmonid migration periods. Pier
implosion requiring IHA coverage is
scheduled to begin in September 2018.
Pier implosion will be restricted from
September 1 to November 30, to
minimize potential impacts on
biological resources in the Bay.
Specific Geographic Region
The SFOBB project area is located in
the central SFB or Bay, between Yerba
Buena Island (YBI) and the city of
Oakland. The western limit of the
project area is the east portal of the YBI
tunnel, located in the city of San
Francisco. The eastern limit of the
project area is located approximately
1,312 feet (400 meters) west of the Bay
Bridge toll plaza, where the new and
former spans of the bridge connect with
land at the OTD in the city of Oakland.
The approximate width of the in-water
work area is 350 meters (1,148 feet).
This includes all in-water areas under
the original bridge and new bridge. All
activities proposed under this IHA
application will be confined to this area.
However, other previous in-water
project activities have taken place in
discrete areas near both YBI and
Treasure Island outside these limits.
Detailed Description of Specific Activity
Construction activities associated
with both dismantling and reuse of
marine foundations of the original east
span bridge may result in the incidental
take of marine mammals. These
activities include the use of highly
controlled charges to dismantle Piers
E19 and E20, as well as pile-driving
activities associated with construction
of a public access facility that will
incorporate reuse Piers E21, E22 and
E23. Pier E2 will also be retained and
incorporated into a public access
facility. However, public access
improvements at Pier E2 will not
require any in-water work and would
not result in incidental take of marine
mammals; therefore, are not discussed
further.
Removal of Piers 19 and 20
The removal of Piers E19 and E20 will
be performed in three phases. The first
phase will use mechanical dismantling
to remove the above-water portions of
E:\FR\FM\12APN1.SGM
12APN1
sradovich on DSK3GMQ082PROD with NOTICES
Federal Register / Vol. 83, No. 71 / Thursday, April 12, 2018 / Notices
the piers, which is not expected to
result in take. The second phase will
use controlled blasting methods for
removal of the in-water portions of the
piers. The third phase will include
dredging of imploded rubble to
specified removal limits, which is also
not expected to result in take. Limits of
removal will be determined at each
location and will result in removal to
between 0.46 and 0.91 meter (1.5 and 3
feet) below the mudline.
Piers E19 and E20 are large cellular
structures through the water column,
which are supported on concrete slabs
and hundreds of driven timber piles
encased in a concrete seal. The timber
piles and concrete seal courses that are
below approved removal limits will
remain in place. Rubble that mounds
above the determined debris removal
elevation limits from the dismantling of
these piers will be removed off-site for
disposal; as was done during the
removal of Piers E6 to E18.
A Blast Attenuation System (BAS)
similar to that used for previous blast
events will be used during all future
controlled blasting events, to minimize
potential impacts on biological
resources in the Bay. The effectiveness
of this minimization measure is
supported by the findings from the
successful removal of Piers E3 to E18.
Each pier will be removed in the
following three phases:
• Pre-blasting activities, including
removing the pier cap and concrete
pedestals, installing and testing the
BAS;
• installing charges, activating the
BAS, and imploding the pier; and
• dredging of imploded rubble to
specified removal limits.
Further detail on the above steps to
remove the marine foundations are
provided. Phase 1: Dismantling the
concrete pedestals and concrete pier cap
by mechanical means (including the use
of torches and excavators mounted with
hoe rams, drills, and cutting tools), and
drilling vertical boreholes where the
charges will be loaded for controlled
blasting. Phase 2: The charges then will
be loaded into the drilled boreholes.
Controlled blasting removal will be
accomplished using hundreds of small
charges, with delays between individual
charges. The controlled blast sequence
for each pier will last approximately 1
to 5 seconds. The controlled blast
removals have been designed to remove
each pier to between 0.46 and 0.91
meter (1.5 and 3 feet) below the
mudline. Phase 3: Dredging of imploded
rubble to specified removal limits.
VerDate Sep<11>2014
19:20 Apr 11, 2018
Jkt 244001
Blast Attenuation System Testing,
Installation, and Deployment
The BAS will be deployed around
each pier being imploded and will be
the same system as that successfully
used for the removal of Piers E3 to E18.
The BAS is a modular system of pipe
manifold frames, placed around each
pier and fed by air compressors to create
a curtain of air bubbles. Each BAS frame
is approximately 15.4 meters long by 1.8
meters wide (50.5 feet long by 6 feet
wide). The BAS to be used will be the
same design that was used at Piers E3
to E18 and will meet the same
specifications. The BAS will be
activated before and during implosion.
As shown during the Pier E3
Demonstration Project and eight
subsequent pier blast events by the
SFOBB Project, the BAS will attenuate
noise and pressure waves generated
during each controlled blast, to
minimize potentially adverse effects on
biological resources that may be nearby.
Before installing the BAS, Caltrans
will move any existing debris on the
Bay floor that may interrupt or conflict
with proper installation of the BAS.
Each BAS frame will be lowered to the
bottom of the Bay by a barge-mounted
crane and will be positioned into place.
Divers will assist frame placement and
will the connect air hoses to the frames.
Based on location around the pier, the
BAS frame elements will be situated
from approximately 8 to 12 meters (25
to 40 feet) from the outside edge of each
pier. The frames will be situated to
contiguously surround each pier. Frame
ends will overlap to ensure no break in
the BAS when operational. Each frame
will be weighted to negative buoyancy
for activation. Compressors will provide
enough pressure to achieve a minimal
air volume fraction of 3 to 4 percent,
consistent with the successful use of
BAS systems in past controlled blasting
activities.
The complete BAS will be installed
and tested during the weeks leading up
to the controlled blast. The BAS test
parameters will include checking
operating levels, flow rate, and a visual
check to determine that the system is
operating correctly. System performance
is anticipated to provide approximately
80 percent noise and pressure
attenuation, based on the results from
the previous SFOBB Project blast events
using a similar system.
Test blasts may be conducted to
ensure that the hydroacoustic
monitoring equipment will be
functional and triggered properly before
the pier implosion event. The test blasts
would be conducted within the
completely installed and operating BAS.
PO 00000
Frm 00014
Fmt 4703
Sfmt 4703
15797
A key requirement of pier implosion
will involve accurately capturing
hydroacoustic information from the
controlled blast. To accomplish this, a
smaller test charge will be used to
trigger recording instrumentation.
Multiple test blasts on the same day
may be required to verify proper
instrument operation and calibrate the
equipment for the implosion events.
These same instruments and others of
the same type will use high-speed
recording devices to capture
hydroacoustic data at both near-field
and far-field monitoring locations
during the implosion.
Test blasts will be scheduled to occur
within two weeks of the scheduled
implosion. Tests will use a charge
weight of approximately 18 grains
(0.0025 pound) or less and will be
placed along one of the longer faces of
the pier. The results from test blasts that
occurred before the implosions of Pier
E3 and E5 indicate that these test blasts
will have minimal impacts on fish and
no impacts on marine mammals (see
Appendix A in application).
Piers E19 and E20 will be imploded
during a single event. Before pier
removal via controlled blasting, Caltrans
will load the bore holes of the piers with
controlled charges. Individual cartridge
charges using electronic blasting caps
have been selected to provide greater
control and accuracy in determining the
individual and total charge weights. Use
of individual cartridges will allow a
refined blast plan that efficiently breaks
concrete while minimizing the amount
of charges needed.
Boreholes will vary in diameter and
depth, and have been designed to
provide optimal efficiency in
transferring the energy created by the
controlled charges to dismantle the
piers. Individual charge weights will
vary from 7 to 11 kilograms (15 to 25
pounds), and the total charge weight for
the Pier E19 and E20 blast event will be
approximately 1,800 kilograms (4,000
pounds). The total number of individual
charges to be used per pier will be
approximately 100. Charges will be
arranged in different levels (decks) and
will be separated in the boreholes by
stemming. Stemming is the insertion of
inert materials (e.g., sand or gravel) to
insulate and retain charges in an
enclosed space. Stemming allows more
efficient transfer of energy into the
structural concrete for fracture, and
further reduces the release of potential
energy into the surrounding water
column. The entire detonation
sequence, consisting of approximately
200 detonations, will last approximately
1 to 5 seconds for each pier; with a
minimum delay time of 9 milliseconds
E:\FR\FM\12APN1.SGM
12APN1
15798
Federal Register / Vol. 83, No. 71 / Thursday, April 12, 2018 / Notices
(msec) between detonations. There will
be approximately half a second delay
between pier blasts to avoid overlap of
pressure waves.
Piers E19 and E20 will be blasted in
a single pier implosion event. These
piers will be removed by blasting down
through the concrete cellular structure
but not through the concrete slab, seal,
and timber piles below. Remaining
concrete seals and timber piles below
the mudline will not be removed.
Reuse of Piers E21 to E23
Piers E19 and E20 will be imploded
during a single event. Before pier
removal via controlled blasting, Caltrans
will load the bore holes of the pier with
controlled charges. Individual cartridge
charges using electronic blasting caps
have been selected to provide greater
control and accuracy in determining the
individual and total charge weights. Use
of individual cartridges will allow a
refined blast plan that efficiently breaks
concrete while minimizing the amount
of charges needed.
Boreholes will vary in diameter and
depth, and have been designed to
provide optimal efficiency in
transferring the energy created by the
controlled charges to dismantle the
piers. Individual charge weights will
vary from 7 to 11 kilograms (15 to 25
pounds), and the total charge weight for
the Pier E19 and E20 blast event will be
approximately 1,800 kilograms (4,000
pounds). The total number of individual
charges to be used per pier will be
approximately 100. Charges will be
arranged in different levels (decks) and
will be separated in the boreholes by
stemming. Stemming is the insertion of
inert materials (e.g., sand or gravel) to
insulate and retain charges in an
enclosed space. Stemming allows more
efficient transfer of energy into the
structural concrete for fracture, and
further reduces the release of potential
energy into the surrounding water
column. The entire detonation
sequence, consisting of approximately
200 detonations, will last approximately
1 to 5 seconds for each pier; with a
minimum delay time of 9 msec between
detonations. There will be
approximately half a second delay
between pier blasts to avoid overlap of
pressure waves.
Proposed mitigation, monitoring, and
reporting measures are described in
detail later in this document (please see
‘‘Proposed Mitigation’’ and ‘‘Proposed
Monitoring and Reporting’’).
Description of Marine Mammals in the
Area of Specified Activities
Sections 3 and 4 of the application
summarize available information
regarding status and trends, distribution
and habitat preferences, and behavior
and life history, of the potentially
affected species. Additional information
regarding population trends and threats
may be found in NMFS’s Stock
Assessment Reports (SAR;
www.nmfs.noaa.gov/pr/sars/) and more
general information about these species
(e.g., physical and behavioral
descriptions) may be found on NMFS’s
website (www.nmfs.noaa.gov/pr/
species/mammals/).
Table 1 lists all species with expected
potential for occurrence in San
Francisco Bay and summarizes
information related to the population or
stock, including regulatory status under
the MMPA and ESA and potential
biological removal (PBR), where known.
For taxonomy, we follow Committee on
Taxonomy (2016). PBR is defined by the
MMPA as the maximum number of
animals, not including natural
mortalities, that may be removed from a
marine mammal stock while allowing
that stock to reach or maintain its
optimum sustainable population (as
described in NMFS’s SARs). While no
mortality is anticipated or authorized
here, PBR and annual serious injury and
mortality from anthropogenic sources
are included here as gross indicators of
the status of the species and other
threats.
Marine mammal abundance estimates
presented in this document represent
the total number of individuals that
make up a given stock or the total
number estimated within a particular
study or survey area. NMFS’s stock
abundance estimates for most species
represent the total estimate of
individuals within the geographic area,
if known, that comprises that stock. For
some species, this geographic area may
extend beyond U.S. waters. All managed
stocks in this region are assessed in
NMFS’s U.S. 2016 SARs (Carretta et al.,
2017). All values presented in Table 1
are the most recent available at the time
of publication and are available in the
2016 SARs (Carretta et al., 2017)
(available online at:
www.nmfs.noaa.gov/pr/sars/draft.htm).
TABLE 1—MARINE MAMMAL SPECIES THAT MAY OCCUR IN THE ACTION AREA
Common name
Scientific name
ESA/
MMPA
status;
Strategic
(Y/N) 1
Stock
Stock abundance
(CV, Nmin, most recent
abundance survey) 2
Annual
M/SI 3
PBR
Order Cetartiodactyla—Cetacea—Superfamily Mysticeti (baleen whales)
Family Eschrichtiidae:
Gray whale .......................
Family Balaenopteridae
(rorquals):
Fin Whale .........................
Humpback Whale .............
Minke Whale ....................
Eschrichtius robustus .............
Eastern North Pacific .............
-; N
20,990 (0.05, 20,125, 2011) ..
624
132
Balaenoptera physalus ...........
Megaptera novaeangliae ........
Balaenoptera acutorostrata ....
California/Oregon/Washington
California/Oregon/Washington
California/Oregon/Washington
E; Y
E; Y
-; N
9,029 (0.12, 8,127, 2014) ......
1,918 (.03, 1,876, 2014) ........
636 (0.72, 369, 2014) ............
81
11
3.5
2
6.5
1.3
sradovich on DSK3GMQ082PROD with NOTICES
Superfamily Odontoceti (toothed whales, dolphins, and porpoises)
Family Physeteridae:
Sperm whale ....................
Family Delphinidae:
Common Bottlenose Dolphin.
Short-Beaked Common
Dolphin.
Family Phocoenidae (porpoises):
Harbor Porpoise ...............
VerDate Sep<11>2014
Physeter macrocephalus ........
California/Oregon/Washington
E; Y
2,106 (0.58, 1,332, 2008) ......
2.7
1.7
Tursiops truncatus ..................
California Coastal ...................
-; N
453 (0.06, 346, 2011) ............
2.7
2
Delphinus delphis ...................
California/Oregon ...................
-; N
969,861 (0.17, 839,325, 2014)
8,393
40
Phocoena phocoena ..............
San Francisco-Russian River
-; N
9,886 (0.51, 6,625, 2011) ......
66
0
19:20 Apr 11, 2018
Jkt 244001
PO 00000
Frm 00015
Fmt 4703
Sfmt 4703
E:\FR\FM\12APN1.SGM
12APN1
15799
Federal Register / Vol. 83, No. 71 / Thursday, April 12, 2018 / Notices
TABLE 1—MARINE MAMMAL SPECIES THAT MAY OCCUR IN THE ACTION AREA—Continued
Common name
Scientific name
ESA/
MMPA
status;
Strategic
(Y/N) 1
Stock
Stock abundance
(CV, Nmin, most recent
abundance survey) 2
PBR
Annual
M/SI 3
Order Carnivora—Superfamily Pinnipedia
Family Otariidae (eared seals
and sea lions):
California Sea Lion ...........
Northern Fur Seal ............
Steller sea lion .................
Family Phocidae (earless
seals):
Harbor seal .......................
Northern Elephant Seal ....
Zalophus californianus ...........
Callorhinus ursinus .................
-; N
-; N
296,750 (N/A, 153,337, 2011)
14,050 (N/A, 7,524, 2013) .....
9,200
451
389
1.8
Eumetopias jubatus ................
United States ..........................
California, Eastern North Pacific.
Eastern ...................................
T; D
41,638 (N/A, 41,638, 2015) ...
2,498
108
Phoca vitulina .........................
Mirounga angustirostris ..........
California ................................
California Breeding .................
-; N
-; N
30,968 (N/A, 27,348, 2012) ...
179,000 (N/A, 81,368, 2010)
1,641
542
43
3.2
1 Endangered Species Act (ESA) status: Endangered (E), Threatened (T)/MMPA status: Depleted (D). A dash (-) indicates that the species is not listed under the
ESA or designated as depleted under the MMPA. Under the MMPA, a strategic stock is one for which the level of direct human-caused mortality exceeds PBR or
which is determined to be declining and likely to be listed under the ESA within the foreseeable future. Any species or stock listed under the ESA is automatically
designated under the MMPA as depleted and as a strategic stock.
2 NMFS marine mammal stock assessment reports online at: www.nmfs.noaa.gov/pr/sars/. CV is coefficient of variation; Nmin is the minimum estimate of stock
abundance. In some cases, CV is not applicable [explain if this is the case].
3 These values, found in NMFS’s SARs, represent annual levels of human-caused mortality plus serious injury from all sources combined (e.g., commercial fisheries, ship strike). Annual M/SI often cannot be determined precisely and is in some cases presented as a minimum value or range. A CV associated with estimated
mortality due to commercial fisheries is presented in some cases.
Note: Italicized species are not expected to be taken or proposed for authorization.
All species that could potentially
occur in the proposed survey areas are
included in Table 1. However, the
temporal or spatial occurrence of the
species italicized in Table 1 is such that
take is not expected to occur, and they
are not discussed further beyond the
explanation provided here. San
Francisco Bay would be considered
extralimital and have not been sighted
during marine mammal monitoring
conducted by Caltrans under past IHAs.
sradovich on DSK3GMQ082PROD with NOTICES
Harbor Seal
Harbor seals are found from Baja
California to the eastern Aleutian
Islands of Alaska. The species primarily
hauls out on remote mainland and
island beaches and reefs, and estuary
areas. Harbor seal tends to forage locally
within 53 miles (85 kilometers) of haul
out sites (Harvey and Goley 2011).
Harbor seal is the most common marine
mammal species observed in the Bay
and also commonly is seen near the
SFOBB east span (Department 2013b,
2013c). Tagging studies have shown that
most seals tagged in the Bay remain in
the Bay (Harvey and Goley 2011;
Manugian 2013). Foraging often occurs
in the Bay, as noted by observations of
seals exhibiting foraging behavior (short
dives less than 5 minutes, moving back
and forth in an area, and sometimes
tearing up prey at the surface).
The molt occurs from May through
June. During both pupping and molt
seasons, the number of seals and the
length of time hauled out per day
increases, with about 60.5 percent of the
population hauled out during this time
versus less than 20 percent in fall
(Yochem et al., 1987; Huber et al., 2001;
VerDate Sep<11>2014
19:20 Apr 11, 2018
Jkt 244001
Harvey and Goley 2011). Mother-pup
pairs spend more time on shore;
therefore, the percentage of seals on
shore at haul out sites increases during
the pupping season (Stewart and
Yochem 1994). Peak numbers of harbor
seals hauling out in central California
occurs during late May to early June,
which coincides with the peak of their
molt. Seals haul out more often and
spend more time on shore to molt.
Yochem et al. (1987) found that harbor
seals at San Miguel Island only hauled
out 11 to 19 percent of the time in fall,
from late October through early
December.
Harbor seal tends to forage at night
and haul out during the day. Harbor seal
predominately hauls out from 10 a.m. to
7 p.m., with a peak in the afternoon
between 1 and 4 p.m. (Yochem et al.,
1987; Stewart and Yochem 1994; Grigg
et al., 2002; London et al., 2012). Harbor
seals in the Bay typically haul out in
groups ranging from a few individuals
to several hundred seals. One known
haul out site is on the southern side of
YBI, approximately 1,600 meters (5,250
feet) from Pier E6 and approximately
2,800 meters (9,190 feet) from Pier E18.
The YBI haul out site had a daily range
of zero to 109 harbor seals hauled out
during September, October, and
November, with the highest numbers
hauled out during afternoon low tides
(Department 2004b). Pile driving for the
SFOBB was not audible to the monitors
just above the haul out site, and no
response to pile driving was observed.
Tide level also can affect haul out
behavior, by exposing and submerging
preferred haul out sites. Tides likely
affect the maximum number of seals
PO 00000
Frm 00016
Fmt 4703
Sfmt 4703
hauled out, but time of day and the
season have the greatest influence on
haul out behavior (Stewart and Yochem
´
1994; Patterson and Acevedo-Gutierrez
2008).
Harbor seals in the Bay are an isolated
population, although about 40 percent
may move a short distance out of the
Bay to forage (Manugian et al. 2017).
The Bay harbor seals likely are
accustomed to a noisy environment
because of construction, vessel traffic,
the Bay Area Rapid Transit (BART)
Transbay Tube, and mechanical noise
(i.e., machinery, generators).
During 251 days of SFOBB monitoring
from 2000 through 2016, 958 harbor
seals were observed in the vicinity of
the SFOBB east span. Harbor seals made
up 90 percent of the marine mammals
observed during monitoring for the
SFOBB Project. In 2015 and 2016, the
number of harbor seals sighted in the
project area increased (8 days of
monitoring and 95 sightings). Foraging
near the project area was common,
particularly in the coves adjacent to the
YBI United States Coast Guard Station
and in Clipper Cove between YBI and
Treasure Island. Foraging also occurred
in a shallow trench area southeast of
YBI (Department 2013a, 2013b). These
sites are more than 900 to 1,525 meters
(3,000 to 5,000 feet) west of Pier E6. In
2015, juvenile harbor seals began
foraging around Piers E2W and E2E of
the new SFOBB east span, and in 2016,
they extended east around Piers E3 to
E5 of the new SFOBB east span.
Foraging can occur throughout the Bay,
and prey abundance and distribution
affect where harbor seals will forage.
Most of the harbor seal sightings were
E:\FR\FM\12APN1.SGM
12APN1
15800
Federal Register / Vol. 83, No. 71 / Thursday, April 12, 2018 / Notices
sradovich on DSK3GMQ082PROD with NOTICES
animals transiting the area, likely
moving from haul out sites or from
foraging areas.
California Sea Lion
California sea lion breeds on the
offshore islands of California from May
through July (Heath and Perrin 2008).
During the non-breeding season, adult
and sub-adult males and juveniles
migrate northward along the coast, to
central and northern California, Oregon,
Washington, and Vancouver Island
(Jefferson et al., 1993). They return
south the following spring (Lowry and
Forney 2005; Heath and Perrin 2008).
Females and some juveniles tend to
remain closer to rookeries (Antonelis et
al., 1990; Melin et al., 2008).
California sea lions have been
observed occupying docks near Pier 39
in San Francisco, about 3.2 miles (5.2
kilometers) from the project area, since
1987. The highest number of sea lions
recorded at Pier 39 was 1,701
individuals in November 2009 (De
Rango, pers. comm., 2013). Occurrence
of sea lions here typically is lowest in
June (breeding season) and highest in
August. Approximately 85 percent of
the animals that haul out at this site are
males, and no pupping has been
observed here or at any other site in the
Bay (Lander, pers. comm., 1999). Pier 39
is the only regularly used haul out site
in the project vicinity, but sea lions
occasionally haul out on human-made
structures, such as bridge piers, jetties,
or navigation buoys (Riedman 1990).
During monitoring for the SFOBB
Project, 80 California sea lions were
observed from 2000 through 2016. The
number of sea lions that were sighted in
the project area decreased in 2015 and
2016. Sea lions appear mainly to be
transiting through the project area rather
than feeding, although two exceptions
have occurred. In 2004, several sea lions
were observed following a school of
Pacific herring that moved through the
project area, and one sea lion was
observed eating a large fish in 2015.
Breeding and pupping occur from mid
to late May until late July. After the
mating season, adult males migrate
northward to feeding areas as far away
as the Gulf of Alaska (Lowry et al.,
1992), and they remain away until
spring (March–May), when they migrate
back to the breeding colonies. Adult
females remain near the rookeries
throughout the year and alternate
between foraging and nursing their pups
on shore until the next pupping/
breeding season.
Northern Elephant Seal
Northern elephant seal is common on
California coastal mainland and island
VerDate Sep<11>2014
19:20 Apr 11, 2018
Jkt 244001
sites, where the species pups, breeds,
rests, and molts. The largest rookeries
are on San Nicolas and San Miguel
islands in the northern Channel Islands.
Near the Bay, elephant seals breed,
˜
molt, and haul out at Ano Nuevo Island,
the Farallon Islands, and Point Reyes
National Seashore.
Northern elephant seals haul out to
give birth and breed from December
through March. Pups remain onshore or
in adjacent shallow water through May.
Both sexes make two foraging
migrations each year: One after breeding
and the second after molting (Stewart
1989; Stewart and DeLong 1995). Adult
females migrate to the central North
Pacific to forage, and males migrate to
the Gulf of Alaska to forage (Robinson
et al. 2012). Pup mortality is high when
they make the first trip to sea in May,
and this period correlates with the time
of most strandings. Pups of the year
return in the late summer and fall, to
haul out at breeding rookery and small
haul out sites, but occasionally they
may make brief stops in the Bay.
Generally, only juvenile elephant
seals enter the Bay and do not remain
long. The most recent sighting near the
project area was in 2012, on the beach
at Clipper Cove on Treasure Island,
when a healthy yearling elephant seal
hauled out for approximately 1 day.
Approximately 100 juvenile northern
elephant seals strand in or near the Bay
each year, including individual
strandings at YBI and Treasure Island
(less than 10 strandings per year).
Northern Fur Seal
Northern fur seal breeds on the
offshore islands of California and in the
Bering Sea from May through July. Two
stocks of Northern fur seals may occur
near the Bay, the California and Eastern
Pacific stocks. The California stock
breeds, pups, and forages off the
California coast. The Eastern Pacific
stock breeds and pups on islands in the
Bering Sea, but females and juveniles
move south to California waters to
forage in the fall and winter months.
Both the California and Eastern
Pacific stocks forage in the offshore
waters of California, but only sick,
emaciated, or injured fur seals enter the
Bay. The Marine Mammal Center
(TMMC) occasionally picks up stranded
fur seals around YBI and Treasure
Island. The rare occurrence of northern
fur seal near the SFOBB east span makes
it unlikely that the species will be
exposed to implosion activities.
Bottlenose Dolphin
This species is found within 0.6 mile
(1 kilometer) of shore and occurs from
northern Baja California, Mexico to
PO 00000
Frm 00017
Fmt 4703
Sfmt 4703
Bodega Bay, with the range extending
north over the last several decades
˜
related to El Nino events and increased
ocean temperatures. As the range of
bottlenose dolphins extended north,
dolphins began entering the Bay in 2010
(Szczepaniak 2013). Until 2016, most
bottlenose dolphins in the Bay were
observed in the western Bay, from the
Golden Gate Bridge to Oyster Point and
Redwood City, although one individual
was observed frequently near the former
Alameda Air Station (Perlman 2017). In
2017, two individuals have been
observed regularly near Alameda
(Keener, pers. comm., 2017) and likely
passed by the project area.
Harbor Porpoise
This species seldom is found in
waters warmer than 62.6 degrees
Fahrenheit (17 degrees Celsius) (Read
1990) or south of Point Conception, and
occurs as far north as the Bering Sea
(Barlow and Hanan 1995; Carretta et al.,
2009; Carretta et al., 2012; Allen and
Angliss 2013). The San Francisco–
Russian River stock is found from
Pescadero, 18 miles (30 kilometers)
south of the Bay, to 99 miles (160
kilometers) north of the Bay at Point
Arena (Carretta et al., 2012). In most
areas, harbor porpoise occurs in small
groups, consisting of just a few
individuals.
Harbor porpoises are seen frequently
outside the Bay, and they began to reenter the Bay in 2008. Keener et al.
(2012) reports sightings of harbor
porpoises from just inside the Bay,
northeast to Tiburon and south to the
SFOBB west span. In 17 years of
monitoring in the project area, 24 harbor
porpoises have been observed, and all
occurred between 2006 and 2015;
including two in 2014, five in 2015 and
15 in 2017. In 2017, the number of
harbor porpoises in the project area
increased significantly. However, the
majority of harbor porpoise observations
made during monitoring for the SFOBB
Project have been at distances ranging
from 2,438 to 3,048 meters (8,000 to
10,000 feet) from the work area.
Gray Whale
The eastern North Pacific population
of gray whales ranges from the southern
tip of Baja California, Mexico to the
Chukchi and Beaufort Seas (Jefferson et
al., 1993). The gray whale makes a welldefined, seasonal north-south migration.
Most of the population summers in the
shallow waters of the northern Bering
Sea, the Chukchi Sea, and the western
Beaufort Sea (Rice and Wolman 1971).
However, some individuals also
summer along the Pacific coast, from
Vancouver Island to central California
E:\FR\FM\12APN1.SGM
12APN1
Federal Register / Vol. 83, No. 71 / Thursday, April 12, 2018 / Notices
(Rice and Wolman 1971; Darling 1984;
Nerini 1984). In October and November,
gray whales begin to migrate south and
follow the shoreline to breeding grounds
along the western coast of Baja
California and the southeastern Gulf of
California (Braham 1984). Gray whales
begin heading north in late winter and
early spring (Rice and Wolman 1971).
The average gray whale migrates 4,660
to 6,213 miles (7,500 to 10,000
kilometers), at a rate of 91 miles/day
(147 kilometers/day) (Jones and Swartz
2002). Gray whales generally calve and
breed during the winter, in lagoons in
Baja California (Jones and Swartz 2002),
although some calves are born along the
California coast during the migration
south.
sradovich on DSK3GMQ082PROD with NOTICES
Marine Mammal Hearing
Hearing is the most important sensory
modality for marine mammals
underwater, and exposure to
anthropogenic sound can have
deleterious effects. To appropriately
assess the potential effects of exposure
to sound, it is necessary to understand
the frequency ranges marine mammals
are able to hear. Current data indicate
that not all marine mammal species
have equal hearing capabilities (e.g.,
Richardson et al., 1995; Wartzok and
Ketten, 1999; Au and Hastings 2008). To
reflect this, Southall et al. (2007)
recommended that marine mammals be
divided into functional hearing groups
based on directly measured or estimated
hearing ranges on the basis of available
behavioral response data, audiograms
derived using auditory evoked potential
techniques, anatomical modeling, and
other data. Note that no direct
measurements of hearing ability have
been successfully completed for
mysticetes (i.e., low-frequency
cetaceans). Subsequently, NMFS (2016)
described generalized hearing ranges for
these marine mammal hearing groups.
Generalized hearing ranges were chosen
based on the approximately 65 dB
threshold from the normalized
composite audiograms, with the
exception for lower limits for lowfrequency cetaceans where the lower
bound was deemed to be biologically
implausible and the lower bound from
Southall et al. (2007) retained. The
functional groups and the associated
frequencies are indicated below (note
that these frequency ranges correspond
to the range for the composite group,
with the entire range not necessarily
reflecting the capabilities of every
species within that group):
• Low-frequency cetaceans
(mysticetes): Generalized hearing is
estimated to occur between
VerDate Sep<11>2014
19:20 Apr 11, 2018
Jkt 244001
approximately 7 hertz (Hz) and 35
kilohertz (kHz);
• Mid-frequency cetaceans (larger
toothed whales, beaked whales, and
most delphinids): Generalized hearing is
estimated to occur between
approximately 150 Hz and 160 kHz;
• High-frequency cetaceans
(porpoises, river dolphins, and members
of the genera Kogia and
Cephalorhynchus; including two
members of the genus Lagenorhynchus,
on the basis of recent echolocation data
and genetic data): Generalized hearing is
estimated to occur between
approximately 275 Hz and 160 kHz.
• Pinnipeds in water; Phocidae (true
seals): Generalized hearing is estimated
to occur between approximately 50 Hz
to 86 kHz;
• Pinnipeds in water; Otariidae (eared
seals): Generalized hearing is estimated
to occur between 60 Hz and 39 kHz.
The pinniped functional hearing
group was modified from Southall et al.
(2007) on the basis of data indicating
that phocid species have consistently
demonstrated an extended frequency
range of hearing compared to otariids,
especially in the higher frequency range
¨
(Hemila et al., 2006; Kastelein et al.,
2009; Reichmuth and Holt, 2013).
For more detail concerning these
groups and associated frequency ranges,
please see NMFS (2016) for a review of
available information. seven marine
mammal species (three cetacean and
four pinniped (three otariid and one
phocid) species) have the reasonable
potential to co-occur with the proposed
survey activities. Please refer to Table 1.
Of the cetacean species that may be
present, one is classified as lowfrequency cetaceans (gray whale), one is
classified as mid-frequency cetaceans
(bottlenose dolphin), and one is
classified as high-frequency cetaceans
(harbor porpoise).
Potential Effects of Specified Activities
on Marine Mammals and Their Habitat
This section includes a summary and
discussion of the ways that components
of the specified activity may impact
marine mammals and their habitat. The
‘‘Estimated Take by Incidental
Harassment’’ section later in this
document includes a quantitative
analysis of the number of individuals
that are expected to be taken by this
activity. The ‘‘Negligible Impact
Analysis and Determination’’ section
considers the content of this section, the
‘‘Estimated Take by Incidental
Harassment’’ section, and the ‘‘Proposed
Mitigation’’ section, to draw
conclusions regarding the likely impacts
of these activities on the reproductive
success or survivorship of individuals
PO 00000
Frm 00018
Fmt 4703
Sfmt 4703
15801
and how those impacts on individuals
are likely to impact marine mammal
species or stocks.
General Information on Potential Effects
Explosives are impulsive sounds,
which are characterized by short
duration, abrupt onset, and rapid decay.
The proposed Caltrans SFOBB work
using controlled charges (i.e., implosion
events) could adversely affect marine
mammal species and stocks by exposing
them to elevated noise levels in the
vicinity of the activity area. Based on
the nature of the other activities
associated with the dismantling of Piers
E6 through E18 of the original SFOBB
East Span (mechanical dismantling) and
measured sound levels from those
activities during past monitoring
associated with previous IHAs, NMFS
does not expect activities other than
implosion events to contribute to
underwater noise levels such that take
of marine mammals would potentially
occur.
Exposure to high intensity sound for
a sufficient duration may result in
behavioral reactions and auditory effects
such as a noise-induced threshold
shift—an increase in the auditory
threshold after exposure to noise
(Finneran et al., 2005). Factors that
influence the amount of threshold shift
include the amplitude, duration,
frequency content, temporal pattern,
and energy distribution of noise
exposure. The magnitude of hearing
threshold shift normally decreases over
time following cessation of the noise
exposure. The amount of threshold shift
just after exposure is the initial
threshold shift. If the threshold shift
eventually returns to zero (i.e., the
threshold returns to the pre-exposure
value), it is a temporary threshold shift
(Southall et al., 2007).
When animals exhibit reduced
hearing sensitivity (i.e., sounds must be
louder for an animal to detect them)
following exposure to an intense sound
or sound for long duration, it is referred
to as a noise-induced threshold shift
(TS). An animal can experience
temporary threshold shift (TTS) or
permanent threshold shift (PTS). TTS
can last from minutes or hours to days
(i.e., there is complete recovery), can
occur in specific frequency ranges (i.e.,
an animal might only have a temporary
loss of hearing sensitivity between the
frequencies of 1 and 10 kHz), and can
be of varying amounts (for example, an
animal’s hearing sensitivity might be
reduced initially by only 6 decibel (dB)
or reduced by 30 dB). PTS is a
permanent loss within a specific
frequency range.
E:\FR\FM\12APN1.SGM
12APN1
sradovich on DSK3GMQ082PROD with NOTICES
15802
Federal Register / Vol. 83, No. 71 / Thursday, April 12, 2018 / Notices
For cetaceans, published TTS data are
limited to the captive bottlenose
dolphin, beluga, harbor porpoise, and
Yangtze finless porpoise (Finneran et
al., 2000, 2002, 2003, 2005, 2007, 2010a,
2010b; Finneran and Schlundt, 2010;
Lucke et al., 2009; Mooney et al., 2009a,
2009b; Popov et al., 2011a, 2011b;
Kastelein et al., 2012a; Schlundt et al.,
2000; Nachtigall et al., 2003, 2004). For
pinnipeds in water, data are limited to
measurements of TTS in harbor seals, an
elephant seal, and California sea lions
(Kastak et al., 1999, 2005; Kastelein et
al., 2012b).
Marine mammal hearing plays a
critical role in communication with
conspecifics, and interpretation of
environmental cues for purposes such
as predator avoidance and prey capture.
Depending on the degree (elevation of
threshold in dB), duration (i.e., recovery
time), and frequency range of TTS, and
the context in which it is experienced,
TTS can have effects on marine
mammals ranging from discountable to
serious (similar to those discussed in
auditory masking, below). For example,
a marine mammal may be able to readily
compensate for a brief, relatively small
amount of TTS in a non-critical
frequency range that occurs during a
time where ambient noise is lower and
there are not as many competing sounds
present. Alternatively, a larger amount
and longer duration of TTS sustained
during time when communication is
critical for successful mother/calf
interactions could have more serious
impacts. Also, depending on the degree
and frequency range, the effects of PTS
on an animal could range in severity,
although it is considered generally more
serious because it is a permanent
condition. Of note, reduced hearing
sensitivity as a simple function of aging
has been observed in marine mammals,
as well as humans and other taxa
(Southall et al., 2007), so one can infer
that strategies exist for coping with this
condition to some degree, though likely
not without cost.
In addition, chronic exposure to
excessive, though not high-intensity,
noise could cause masking at particular
frequencies for marine mammals that
utilize sound for vital biological
functions (Clark et al., 2009). Acoustic
masking occurs when other noises, such
as those from human sources, interfere
with animal detection of acoustic
signals such as communication calls,
echolocation sounds, and
environmental sounds important to
marine mammals. Therefore, under
certain circumstances, marine mammals
whose acoustical sensors or
environment are being severely masked
could also be impaired from maximizing
VerDate Sep<11>2014
19:20 Apr 11, 2018
Jkt 244001
their performance fitness in survival
and reproduction.
Masking occurs at the frequency band,
which the animals utilize. However,
lower frequency man-made noises are
more likely to affect detection of
communication calls and other
potentially important natural sounds
such as surf and prey noise. It may also
affect communication signals when they
occur near the noise band and thus
reduce the communication space of
animals (e.g., Clark et al., 2009) and
cause increased stress levels (e.g., Foote
et al., 2004; Holt et al., 2009).
Unlike TS, masking, which can occur
over large temporal and spatial scales,
can potentially affect the species at
population, community, or even
ecosystem levels, as well as individual
levels. Masking affects both senders and
receivers of the signals and could have
long-term chronic effects on marine
mammal species and populations.
Recent science suggests that low
frequency ambient sound levels have
increased by as much as 20 dB (more
than 3 times in terms of sound pressure
level) in the world’s ocean from preindustrial periods, and most of these
increases are from distant shipping
(Hildebrand 2009). For Caltrans’
proposed SFOBB construction activities,
noises from controlled blasting is not
likely to contribute to the elevated
ambient noise levels in the project area
in such a way as to increasing potential
for or severity of masking. Baseline
ambient noise levels in the Bay are very
high due to ongoing shipping,
construction and other activities in the
Bay, and the sound associated with the
controlled blasting activities would be
very brief.
Finally, exposure of marine mammals
to certain sounds could lead to
behavioral disturbance (Richardson et
al., 1995), such as: Changing durations
of surfacing and dives, number of blows
per surfacing, or moving direction and/
or speed; reduced/increased vocal
activities; changing/cessation of certain
behavioral activities (such as socializing
or feeding); visible startle response or
aggressive behavior (such as tail/fluke
slapping or jaw clapping); avoidance of
areas where noise sources are located;
and/or flight responses (e.g., pinnipeds
flushing into water from haul outs or
rookeries).
The onset of behavioral disturbance
from anthropogenic noise depends on
both external factors (characteristics of
noise sources and their paths) and the
receiving animals (hearing, motivation,
experience, demography) and is also
difficult to predict (Southall et al.,
2007). For impulse noises (such as the
proposed controlled implosions
PO 00000
Frm 00019
Fmt 4703
Sfmt 4703
associated with the dismantling of the
original SFOBB spans), NMFS uses
received levels of 165 dB SEL to predict
the onset of behavioral harassment for
mid-frequency cetaceans and phocid
pinnipeds (bottlenose dolphins and
harbor seals and northern elephant
seals, respectively); 135 dB SEL for
high-frequency cetaceans (harbor
porpoises); and 183 dB SEL for otariid
pinnipeds (California sea lions and
northern fur seals).
The biological significance of many of
these behavioral disturbances is difficult
to predict, especially if the detected
disturbances appear minor. However,
the consequences of behavioral
modification could be biologically
significant if the change affects growth,
survival, and/or reproduction, which
depends on the severity, duration, and
context of the effects.
Potential Effects From Controlled Pier
Implosion
It is expected that an intense impulse
from the proposed controlled blasting of
Piers E19 and E20 would have the
potential to impact marine mammals in
the vicinity of the activity. The majority
of impacts would be startle behavioral
responses and temporary behavioral
modification of marine mammals.
However, a few individual animals
could be exposed to sound levels that
would cause TTS.
The underwater explosion would
send a shock wave and blast noise
through the water, release gaseous byproducts, create an oscillating bubble,
and cause a plume of water to shoot up
from the water surface. The shock wave
and blast noise are of most concern to
marine animals. The effects of an
underwater explosion on a marine
mammal depends on many factors,
including the size, type, and depth of
both the animal and the explosive
charge; the depth of the water column;
and the standoff distance between the
charge and the animal, as well as the
sound propagation properties of the
environment. Potential impacts can
range from brief effects (such as
behavioral disturbance), tactile
perception, physical discomfort, slight
injury of the internal organs and the
auditory system, to death of the animal
(Yelverton et al., 1973; DoN, 2001).
Non-lethal injury includes slight injury
to internal organs and the auditory
system; however, delayed lethality can
be a result of individual or cumulative
sublethal injuries (DoN, 2001).
Immediate lethal injury would be a
result of massive combined trauma to
internal organs as a direct result of
proximity to the point of detonation
(DoN 2001). Generally, the higher the
E:\FR\FM\12APN1.SGM
12APN1
sradovich on DSK3GMQ082PROD with NOTICES
Federal Register / Vol. 83, No. 71 / Thursday, April 12, 2018 / Notices
level of impulse and pressure level
exposure, the more severe the impact to
an individual.
Injuries resulting from a shock wave
take place at boundaries between tissues
of different density. Different velocities
are imparted to tissues of different
densities, and this can lead to their
physical disruption. Blast effects are
greatest at the gas-liquid interface
(Landsberg 2000). Gas-containing
organs, particularly the lungs and
gastrointestinal (GI) tract, are especially
susceptible (Goertner 1982; Hill 1978;
Yelverton et al., 1973). In addition, gascontaining organs including the nasal
sacs, larynx, pharynx, trachea, and
lungs may be damaged by compression/
expansion caused by the oscillations of
the blast gas bubble. Intestinal walls can
bruise or rupture, with subsequent
hemorrhage and escape of gut contents
into the body cavity. Less severe GI tract
injuries include contusions, petechiae
(small red or purple spots caused by
bleeding in the skin), and slight
hemorrhaging (Yelverton et al., 1973).
Because the ears are the most
sensitive to pressure, they are the organs
most sensitive to injury (Ketten 2000).
Sound-related damage associated with
blast noise can be theoretically distinct
from injury from the shock wave,
particularly farther from the explosion.
If an animal is able to hear a noise, at
some level it can damage its hearing by
causing decreased sensitivity (Ketten
1995). Sound-related trauma can be
lethal or sublethal. Lethal impacts are
those that result in immediate death or
serious debilitation in or near an intense
source and are not, technically, pure
acoustic trauma (Ketten 1995). Sublethal
impacts include hearing loss, which is
caused by exposures to perceptible
sounds. Severe damage (from the shock
wave) to the ears includes tympanic
membrane rupture, fracture of the
ossicles, damage to the cochlea,
hemorrhage, and cerebrospinal fluid
leakage into the middle ear. Moderate
injury implies partial hearing loss due
to tympanic membrane rupture and
blood in the middle ear. Permanent
hearing loss also can occur when the
hair cells are damaged by one very loud
event, as well as by prolonged exposure
to a loud noise or chronic exposure to
noise. The level of impact from blasts
depends on both an animal’s location
and, at outer zones, on its sensitivity to
the residual noise (Ketten 1995).
The above discussion concerning
underwater explosions only pertains to
open water detonations in a free field.
Caltrans’ demolition of Piers E19 and
E20 using controlled implosion uses a
confined detonation method, meaning
that the charges would be placed within
VerDate Sep<11>2014
19:20 Apr 11, 2018
Jkt 244001
the structure. Therefore, most energy
from the explosive shock wave would
be absorbed through the destruction of
the structure itself, and would not
propagate through the open water.
Measurements and modeling from
confined underwater detonation for
structure removal showed that energy
from shock waves and noise impulses
were greatly reduced in the water
column compared to expected levels
from open water detonations (Hempen
et al., 2007; Department 2016).
Therefore, with monitoring and
mitigation measures discussed below,
Caltrans’ controlled implosions of Piers
E19 and E20 are not likely to have
injury or mortality effects on marine
mammals in the project vicinity.
Instead, NMFS considers that Caltrans’
proposed controlled implosions in the
San Francisco Bay are most likely to
cause behavioral harassment and may
cause TTS in a few individual of marine
mammals, as discussed below.
Changes in marine mammal behavior
are expected to result from acute stress,
or startle, responses. This expectation is
based on the idea that some sort of
physiological trigger must exist to
change any behavior that is already
being performed, and this may occur
due to being startled by the implosion
events. The exception to this
expectation is the case of behavioral
changes due to auditory masking
(increasing call rates or volumes to
counteract increased ambient noise).
Masking is not likely since the Caltrans’
controlled implosion would only
consist of five to six short, sequential
detonations that last for approximately
3–4 seconds each.
The removal of the SFOBB East Span
is not likely to negatively affect the
habitat of marine mammal populations
because no permanent loss of habitat
will occur, and only a minor, temporary
modification of habitat will occur due to
the addition of sound and activity
associated with the dismantling
activities.
Project activities will not affect any
pinniped haul out sites or pupping sites.
The YBI harbor seal haul out site is on
the opposite site of the island from the
SFOBB Project area. Because of the
distance and the island blocking the
sound, underwater noise and pressure
levels from the SFOBB Project will not
reach the haul out site. Other haul out
sites for sea lions and harbor seals are
at a sufficient distance from the SFOBB
Project area that they will not be
affected. The closest recognized harbor
seal pupping site is at Castro Rocks,
approximately 8.7 miles (14 kilometers)
from the SFOBB Project area. No sea
lion rookeries are found in the Bay.
PO 00000
Frm 00020
Fmt 4703
Sfmt 4703
15803
The addition of underwater sound
from SFOBB Project activities to
background noise levels can constitute a
potential cumulative impact on marine
mammals. However, these potential
cumulative noise impacts will be short
in duration and would not occur in
biologically important areas, would not
significantly affect biologically
important activities, and are not
expected to have significant
environmental effects, as noted in the
original FHWA 2001 FEIS for the
SFOBB project, incorporated by
reference into NMFS’ 2003 EA and
subsequent Supplemental EAs (2009
and 2015) for the issuance of IHAs for
the SFOBB project.
Marine mammal forage on fish within
SFB and pier implosions have the
potential to injure or kill fish in the
immediate area. During previous pier
implosion and pile driving activities,
Caltrans reported mortality to prey
species of marine mammals, including
northern anchovies and Pacific herring
(Department 2016), averaging
approximately 200 fish per implosion
event (none of which were ESA-listed
species and none of which are managed
under a Fishery Management Plan).
These few isolated fish mortality events
are not anticipated to have a substantial
effect on prey species populations or
their availability as a food resource for
marine mammals.
Studies on explosives also suggest
that larger fish are generally less
susceptible to death or injury than small
fish, and results of most studies are
dependent upon specific biological,
environmental, explosive, and data
recording factors. For example,
elongated forms that are round in cross
section are less at risk than deep-bodied
forms; orientation of fish relative to the
shock wave may also affect the extent of
injury; and finally, open water pelagic
fish, such as those expected to be in the
project area, seem to be less affected
than reef fishes.
The huge variation in fish
populations, including numbers,
species, sizes, and orientation and range
from the detonation point, makes it very
difficult to accurately predict mortalities
at any specific site of detonation. Most
fish species experience a large number
of natural mortalities, especially during
early life-stages, and any small level of
mortality caused by the Caltrans’
controlled implosion events will likely
be insignificant to the population as a
whole. This negligible effect on
population levels of forage fish should
ensure continued prey availability for
marine mammal species in the area.
E:\FR\FM\12APN1.SGM
12APN1
15804
Federal Register / Vol. 83, No. 71 / Thursday, April 12, 2018 / Notices
Estimated Take
This section provides an estimate of
the number of incidental takes proposed
for authorization through this IHA,
which will inform both NMFS’
consideration of ‘‘small numbers’’ and
the negligible impact determination.
Harassment is the only type of take
expected to result from these activities.
Except with respect to certain activities
not pertinent here, section 3(18) of the
MMPA defines ‘‘harassment’’ as any act
of pursuit, torment, or annoyance which
(i) has the potential to injure a marine
mammal or marine mammal stock in the
wild (Level A harassment); or (ii) has
the potential to disturb a marine
mammal or marine mammal stock in the
wild by causing disruption of behavioral
patterns, including, but not limited to,
migration, breathing, nursing, breeding,
feeding, or sheltering (Level B
harassment).
Authorized takes would be by Level B
harassment only, in the form of
disruption of behavioral patterns and
TTS, for individual marine mammals
resulting from exposure to pile driving
and controlled blasting. Based on the
nature of the activity and the
anticipated effectiveness of the
mitigation measures such as the use of
a blast attenuation system and
shutdown zones, Level A harassment is
neither anticipated nor proposed to be
authorized.
As described previously, no mortality
is anticipated or proposed to be
authorized for this activity. Below we
describe how the take is estimated.
Described in the most basic way, we
estimate take by considering: (1)
Acoustic thresholds above which NMFS
believes the best available science
indicates marine mammals will be
behaviorally harassed or incur some
degree of permanent hearing
impairment; (2) the area or volume of
water that will be ensonified above
these levels in a day; (3) the density or
occurrence of marine mammals within
these ensonified areas; and, (4) and the
number of days of activities. Below, we
describe these components in more
detail and present the proposed take
estimate.
Acoustic Thresholds
Using the best available science,
NMFS has developed acoustic
thresholds that identify the received
level of underwater sound above which
exposed marine mammals would be
reasonably expected to be behaviorally
harassed (equated to Level B
harassment) or to incur PTS of some
degree (equated to Level A harassment).
Thresholds have also been developed to
identify the pressure levels above which
animals may incur different types of
tissue damage from exposure to pressure
waves from explosive detonation.
Level B Harassment for non-explosive
sources—Though significantly driven by
received level, the onset of behavioral
disturbance from anthropogenic noise
exposure is also informed to varying
degrees by other factors related to the
source (e.g., frequency, predictability,
duty cycle), the environment (e.g.,
bathymetry), and the receiving animals
(hearing, motivation, experience,
demography, behavioral context) and
can be difficult to predict (Southall et
al., 2007, Ellison et al., 2011). Based on
what the available science indicates and
the practical need to use a threshold
based on a factor that is both predictable
and measurable for most activities,
NMFS uses a generalized acoustic
threshold based on received level to
estimate the onset of behavioral
harassment. NMFS predicts that marine
mammals are likely to be behaviorally
harassed in a manner we consider Level
B harassment when exposed to
underwater anthropogenic noise above
received levels of 120 dB re 1 mPa (rms)
for continuous (e.g. vibratory piledriving, drilling) and above 160 dB re 1
mPa (rms) for non-explosive impulsive
(e.g., seismic airguns) or intermittent
(e.g., scientific sonar) sources.
Caltrans’s proposed activity includes
the use of continuous (vibratory pile
driving) and impulsive (impact pile
driving) sources, and therefore the 120
and 160 dB re 1 mPa (rms) thresholds are
applicable.
Level A harassment for non-explosive
sources—NMFS’ Technical Guidance
for Assessing the Effects of
Anthropogenic Sound on Marine
Mammal Hearing (Technical Guidance,
2016) identifies dual criteria to assess
auditory injury (Level A harassment) to
five different marine mammal groups
(based on hearing sensitivity) as a result
of exposure to noise from two different
types of sources (impulsive or nonimpulsive). Caltrans’ proposed activity
includes the use of impulsive (impact
driving) AND non-impulsive (vibratory
driving) sources.
These thresholds are provided in the
table below. The references, analysis,
and methodology used in the
development of the thresholds are
described in NMFS 2016 Technical
Guidance, which may be accessed at:
https://www.nmfs.noaa.gov/pr/acoustics/
guidelines.htm.
Explosive sources—Based on the best
available science, NMFS uses the
acoustic and pressure thresholds
indicated in Table 2 to predict the onset
of behavioral harassment, PTS, tissue
damage, and mortality.
Based on the best available scientific
data, NMFS’ 2016 Technical Guidance
for Assessing the Effects of
Anthropogenic Sound on Marine
Mammal Hearing includes acoustic
thresholds related to PTS and TTS for
impulsive sounds that are expressed as
weighted, cumulative sound exposure
levels (SELcum) and unweighted peak
sound pressure levels (SPLPK), as
presented in Table 3.
TABLE 2—NMFS TAKE THRESHOLDS FOR MARINE MAMMALS FROM UNDERWATER IMPLOSIONS
Level B harassment
Group
Level A harassment
Species
Behavioral
Bottlenose dolphin
High-freq cetacean ...
sradovich on DSK3GMQ082PROD with NOTICES
Mid-freq cetacean ....
Harbor porpoise .....
Phocidae ..................
Harbor seal &
northern elephant
seal.
California sea lion &
northern fur seal.
Otariidae ...................
TTS
PTS
165 dB SEL
.................
135 dB SEL
170 dB SEL or 224
dB SPLpk.
140 dB SEL or 196
dB SPLpk.
170 dB SEL or 212
dB SPLpk.
185 dB SEL or 230
dB SPLpk.
155 dB SEL or 202
dB SPLpk.
185 dB SEL or 218
dB SPLpk.
188 dB SEL or 226
dBpk.
Serious injury
Gastrointestinal
tract
Mortality
203 dB SEL or 232
dB SPLpk.
165 dB SEL
183 dB SEL
237 dB SPL
Lung
39.1M 1/3 (1 + [D/
10.081]) 1/2 Pasec.
where: M = mass of
the animals in kg.
D = depth of animal
in m.
* Note: All dB values are referenced to 1 μPa. SPLpk = Peak sound pressure level; psi = pounds per square inch.
VerDate Sep<11>2014
19:20 Apr 11, 2018
Jkt 244001
PO 00000
Frm 00021
Fmt 4703
Sfmt 4703
E:\FR\FM\12APN1.SGM
12APN1
91.4M 1/3 (1 + [D/
10.081]) 1/2 Pasec
where: M = mass of
the animals in kg
D = depth of animal
in m.
15805
Federal Register / Vol. 83, No. 71 / Thursday, April 12, 2018 / Notices
Table 3. Thresholds identifying the onset of Permanent Threshold Shift
..
·····
•••••
He~rin,g G~:oup
...
.....•.
..··
PTS Onset Acoustic. 'fltresholds"'
.
·.
• .•.· · .. ·. ltnpplsiv¢
(Received Level)
. . ..
•..•.. ·>··· ..
.
.·
.......
..... ·..
N'on~it.np:ulsive
Cell!
LE,LF,24h: 199 dB
LE,LF,24h: 183 dB
Cel/3
Cel/4
Lpk,flat: 230 dB
LE,MF,24h: 198 dB
LE,MF,24h: 185 dB
Cel/5
Cel/6
Lpk,flat: 202 dB
LE,HF,24h: 173 dB
LE,HF,24h: 155 dB
Celll
Cel/8
Lpk,flat: 218 dB
LE,PW,24h: 201 dB
LE,PW,24h: 185 dB
Cel/9
Cel/10
Lpk,flat: 232 dB
··. •.·.
Cel/2
Lpk,flat: 219 dB
·
LE,OW,24h: 219 dB
Low-Frequency (LF)
Cetaceans
Mid-Frequency (MF)
Cetaceans
High-Frequency (HF)
Cetaceans
Phocid Pinnipeds (PW)
(Underwater)
Otariid Pinnipeds (OW)
(Underwater)
LE,OW,24h: 203 dB
*Dual metric acoustic thresholds for impulsive sounds: Use whichever results in the largest isopleth for
calculating PTS onset. If a non-impulsive sound has the potential of exceeding the peak sound pressure
level thresholds associated with impulsive sounds, these thresholds should also be considered.
VerDate Sep<11>2014
19:20 Apr 11, 2018
Jkt 244001
PO 00000
Frm 00022
Fmt 4703
Sfmt 4725
E:\FR\FM\12APN1.SGM
12APN1
EN12AP18.003
sradovich on DSK3GMQ082PROD with NOTICES
Note: Peak sound pressure (Lpk) has a reference value of 1 f!Pa, and cumulative sound exposure level (LE)
has a reference value of lf!Pa2s. In this Table, thresholds are abbreviated to reflect American National
Standards Institute standards (ANSI 2013). However, peak sound pressure is defined by ANSI as
incorporating frequency weighting, which is not the intent for this Technical Guidance. Hence, the
subscript "flat" is being included to indicate peak sound pressure should be flat weighted or unweighted
within the generalized hearing range. The subscript associated with cumulative sound exposure level
thresholds indicates the designated marine mammal auditory weighting function (LF, MF, and HF
cetaceans, and PW and OW pinnipeds) and that the recommended accumulation period is 24 hours. The
cumulative sound exposure level thresholds could be exceeded in a multitude of ways (i.e., varying
exposure levels and durations, duty cycle). When possible, it is valuable for action proponents to indicate
the conditions under which these acoustic thresholds will be exceeded.
15806
Federal Register / Vol. 83, No. 71 / Thursday, April 12, 2018 / Notices
Here, we describe operational and
environmental parameters of the activity
that will feed into identifying the area
ensonified above the acoustic
thresholds.
For pile removal activities,
hydroacoustic monitoring was
performed during the implosions of
Piers E3 through E18. Results for this
monitoring were used to determine
distances to marine mammal threshold
criteria for underwater blasting. The
criterion for lung injury and mortality to
marine mammals is dependent on the
mass of the animal and the depth of the
animal in the water column; animals
smaller in mass are more susceptible to
VerDate Sep<11>2014
19:20 Apr 11, 2018
Jkt 244001
injury from impulse pressures. The
criterion is an impulse metric,
expressed in pascal-second or psi-msec
(Table 5). The estimated mass of a
juvenile fur seal (15 kilograms (33
pounds)), was used in the lung injury
and mortality calculations, because this
will be the smallest animal potentially
to be exposed to the implosions. The
depth at which the animal is exposed
also affects the criterion threshold
calculation. The water depth around
Piers E19 and E20 is very shallow, at 3
to 4 meters (10 to 12 feet). Although
implosions will take place in shallow
areas, marine mammals are more likely
to be present in slightly deeper waters.
Therefore, an average depth for the
PO 00000
Frm 00023
Fmt 4703
Sfmt 4703
project area of 6 meters (20 feet) was
used in the threshold calculation.
Caltrans proposes to use
hydroacoustic monitoring results from
the implosions of Piers E3 through E18
to estimate distances to marine mammal
thresholds for the implosion of Piers
E19 and E20 (Department 2015a, 2016).
Measured distances from the implosion
of Piers E17 to E18 (two-pier implosion
event) were used to estimate distances
to threshold criteria for the implosion of
Piers E19 and E20. The measured
distances to threshold criteria from the
previous Pier E17 and E18 implosion
event are shown in Tables 5 and 6.
Depictions of the isopleths for all
functional hearing groups is found in
Figures 9–13 in the application.
E:\FR\FM\12APN1.SGM
12APN1
EN12AP18.004
sradovich on DSK3GMQ082PROD with NOTICES
Ensonified Area
15807
Federal Register / Vol. 83, No. 71 / Thursday, April 12, 2018 / Notices
TABLE 5—MEASURED DISTANCES TO UNDERWATER BLASTING THRESHOLD CRITERIA FOR LEVEL B BEHAVIORAL AND TTS
AND LEVEL A PTS FROM THE PREVIOUS IMPLOSION OF PIERS E17 AND E18 IN A SINGLE EVENT AND ESTIMATED
DISTANCES TO THESE THRESHOLD CRITERIA FOR THE PROPOSED IMPLOSION OF PIERS E19 AND E20 IN A SINGLE
EVENT
TTS 1
Behavioral
Species hearing group
PTS 1
165 dB
SELcum
224 dB Peak
170 dB
SELcum
230 dB Peak
Piers E17–E18 Measured
511 feet ..........
40.84 meters
109.42 meters
27.13 meters
37.8 meters.
Piers E19–E20 Estimate ..
200 meters .....
50 meters .....
120 meters ....
30 meters .....
40 meters.
Threshold
135 dB
SELcum
196 dB Peak
140 dB
SELcum
202 dB Peak
155 dB
SELcum
Piers E17–E18 Measured
1142.1 meters
279.2 meters
802.54 meters
278.28 meters.
Piers E19–E20 Estimate ..
1,220 meters ..
290 meters ...
830 meters ....
185.01 meters.
200 meters ...
Threshold
165 dB
SELcum
212 dB Peak
170 dB
SELcum
218 dB Peak
185 dB
SELcum
Piers E17–E18 Measured
Piers E19–E20 Estimate ..
278.59 meters
290 meters .....
92.96 meters
100 meters ...
195.38 meters
200 meters ....
61.57 meters
70 meters .....
67.36 meters.
70 meters.
Threshold
183 dB
SELcum
226 dB Peak
188 dB
SELcum
232 dB Peak
203 dB
SELcum.
Piers E17–E18 Measured
75.9 meters ....
35.66 meters
53.04 meters
23.47 meters
18.29 meters.
Piers E19–E20 Estimate ..
80 meters .......
40 meters .....
60 meters ......
30 meters ....
20 meters.
Threshold
Mid-Frequency Cetaceans
(Dolphins).
High-Frequency Cetaceans
(Porpoises).
Phocid Pinnipeds (Seals) ....
Otariid Pinnipeds (Sea
Lions).
185 dB
SELcum
290 meters.
Notes:
1 For the TTS and PTS criteria thresholds with dual criteria, the largest criteria distances (i.e., more conservative) are shown in bold.
Threshold Source: NMFS 2016.
Isopleth Distance Sources: Estimated distances to threshold criteria for the implosion of two small piers were determined based on measured
distance to threshold criteria from the implosion of Piers E17 and E18.
TABLE 6—ESTIMATED DISTANCES TO UNDERWATER BLASTING THRESHOLD CRITERIA FOR LEVEL A GI TRACT AND LUNG
INJURY AND MORTALITY FOR IMPLOSION OF PIER E3, TWO SMALL PIERS AND FOUR SMALL PIERS
Lung 1
GI tract
Mortality 1
91.4 (15 kg)1/3 (1 +
[6/10.081]) 1/2 = 285
Pa-sec
Threshold
237 dB Peak
104 psi
39.1 (15 kg)1/3 (1 +
[6/10.081]) 1/2 = 122
Pa-sec
Piers E17–E18 Measured.
Pier Implosion Estimate.
55 feet ............................
55 feet ............................
<40 feet .....................
<40 feet.
27 meters (89 feet) ........
27 meters (89 feet) ........
<12 meters (<40 feet)
<12 meters (<40
feet).
Species
All Species ........
sradovich on DSK3GMQ082PROD with NOTICES
Notes:
Lung injury and mortality threshold calculations are for a 15-kilogram (33-pound) juvenile fur seal, the smallest marine mammal with the potential to be present in the project area.
Threshold Source: Finneran and Jenkins 2012.
Isopleth Distance Sources: Estimated distances to threshold criteria for the implosion of piers were determined based on measured distance to
threshold criteria from the implosions of Pier E4, Piers E17 to E18, Piers E11 to E13 and Piers E14 to E16.
For pile driving, the distance to the
marine mammal threshold criteria for
vibratory and impact driving were
calculated based on hydroacoustic
measurements collected during previous
pile-driving activities for the SFOBB
Project and other projects, involving
similar activities under similar
conditions. Measured sound pressure
levels from other projects came from
Caltrans’ Compendium of Pile Driving
Sound Data (Department 2007), which
provides information on sound
pressures resulting from pile driving
measured throughout Northern
California. Distances to marine mammal
threshold criteria were calculated for all
pile types and installation methods
listed above. These distances were
calculated using the NMFS-provided
companion User Spreadsheet.
TABLE 7—NMFS USER SPREADSHEET INPUT VALUES FOR PILE DRIVING
Vibratory driving of steel piles
H-Pile (vibratory)
24 inch steel (vibratory)
Spreadsheet Tab Used ...................................................
Source Level (RMS SPL) ................................................
(A) Non-Impulsive, Cont ....
150 .....................................
(A) Non-Impulsive, Cont ....
165 .....................................
VerDate Sep<11>2014
19:20 Apr 11, 2018
Jkt 244001
PO 00000
Frm 00024
Fmt 4703
Sfmt 4703
E:\FR\FM\12APN1.SGM
12APN1
36 inch steel (vibratory)
(A) Non-Impulsive, Cont.
170.
15808
Federal Register / Vol. 83, No. 71 / Thursday, April 12, 2018 / Notices
TABLE 7—NMFS USER SPREADSHEET INPUT VALUES FOR PILE DRIVING—Continued
Vibratory driving of steel piles
H-Pile (vibratory)
24 inch steel (vibratory)
36 inch steel (vibratory)
Weighting Factor Adjustment (kHz) ................................
a) Activity Duration (h) within 24-h period .......................
Propagation (xLogR) .......................................................
Distance of source level (meters) * .................................
Other factors.
2.5 ......................................
0.5 ......................................
15 .......................................
10 .......................................
2.5 ......................................
1 .........................................
15 .......................................
10 .......................................
Impact driving of steel piles
H-Pile (impact)
24 inch steel (impact)
Spreadsheet Tab Used ...................................................
Source Level (Single Strike/shot SEL) ............................
Weighting Factor Adjustment (kHz) ................................
a) Number of strikes in 1 h .............................................
a) Activity Duration (h) within 24-h period .......................
Propagation (xLogR) .......................................................
Distance of source level (meters) * .................................
Other factors ....................................................................
(E.1) Impact pile driving ....
160 .....................................
2 .........................................
200 .....................................
6 .........................................
15 .......................................
10 .......................................
............................................
(E.1) Impact pile driving ....
167 * ...................................
2 .........................................
450 .....................................
4 .........................................
15 .......................................
10 .......................................
Using Bubble Curtain * ......
Pile proofing (impact)
H-Pile (impact)
24 inch steel (impact)
Spreadsheet Tab Used ...................................................
Source Level (Single Strike/shot SEL) ............................
Weighting Factor Adjustment (kHz) ................................
a) Number of strikes in 1 h .............................................
a) Activity Duration (h) within 24-h period .......................
Propagation (xLogR) .......................................................
Distance of source level (meters) * .................................
Other factors.
(E.1) Impact pile driving ....
160 .....................................
2 .........................................
20 .......................................
2 .........................................
15 .......................................
10 .......................................
(E.1) Impact pile driving ....
177 .....................................
2 .........................................
20 .......................................
2 .........................................
15 .......................................
10 .......................................
2.5.
1.333333.
15.
10.
36 inch steel (impact)
(E.1) Impact pile driving.
170. *
2.
600.
4.
15.
10.
Using Bubble Curtain.*
36 inch steel (impact)
Impact driving of concrete piles
24 inch concrete (impact)
Spreadsheet Tab Used ...................................................
Source Level (Single Strike/shot SEL) ............................
Weighting Factor Adjustment (kHz) ................................
a) Number of strikes in 1 h .............................................
a) Activity Duration (h) within 24-h period .......................
Propagation (xLogR) .......................................................
Distance of source level (meters) * .................................
Other factors ....................................................................
(E.1) Impact pile driving ....................................................
160 .....................................................................................
2 .........................................................................................
1200 ...................................................................................
5 .........................................................................................
15 .......................................................................................
10 .......................................................................................
............................................................................................
(E.1) Impact pile driving.
180.
2.
20.
2.
15.
10.
36 inch concrete (impact)
(E.1) Impact pile driving.
160.*
2.
1400.
5.
15.
10.
Using Bubble Curtain.*
* Attenuated value—Bubble curtain is assumed to provide 10dB of attenuation.
For calculation of SELcum threshold
distances, the following assumptions
were made:
• Only one type/size of pile will be
installed on the same day;
• Only one pile installation method,
impact or vibratory, will be performed
on the same day;
• A maximum of four steel pipe piles
will be installed (impact driving or
vibratory) on the same day;
• A maximum of six H-piles will be
installed (impact or vibratory) on the
same day; and
• A maximum of two pile will be
proof-tested with an impact hammer on
the same day; administering a maximum
of 20 strikes per pile.
The distances to the marine mammal
threshold criteria for these pile driving
and pile removal activities are shown in
Table 8.
TABLE 8—DISTANCES TO LEVELS A AND B HARASSMENT THRESHOLD CRITERIA FOR IMPACT AND VIBRATORY PILE
DRIVING AND PILE REMOVAL
Parameters
Level B ZOI radii (meters)
Piles per
day
Attenuation system
160 dB
RMS
Drive method
H-Pile ..................
24 inch steel .......
Vibratory .............
Vibratory .............
6
4
None ..................
None ..................
NA
NA
36 inch steel .......
sradovich on DSK3GMQ082PROD with NOTICES
Pile size and type
Vibratory .............
4
None ..................
NA
H-Pile ..................
24 inch steel .......
36 inch steel .......
24 inch concrete
36 inch concrete
H-Pile ..................
24 inch steel .......
Impact ................
Impact ................
Impact ................
Impact ................
Impact ................
Proof Testing .....
Proof Testing .....
6
4
4
5
5
2
2
None ..................
Bubble Curtain ...
Bubble Curtain ...
None ..................
Bubble Curtain ...
None ..................
None ..................
100
215
541
46
117
100
1,000
VerDate Sep<11>2014
19:20 Apr 11, 2018
Jkt 244001
PO 00000
Frm 00025
Fmt 4703
120 dB RMS
1,000 ..................
Calculated ..........
Practical 2,000 ...
Calculated ..........
Practical 2,000 ...
NA ......................
NA ......................
NA ......................
NA ......................
NA ......................
NA ......................
NA ......................
Sfmt 4703
Level A ZOI radii (meters)
Lowfrequency
cetaceans
Midfrequency
cetaceans
Highfrequency
cetaceans
Phocid
pinnipeds
Otariid
pinnipeds
1
13
1
1
2
19
1
8
1
1
33
3
49
20
1
33
127
243
97
107
3
46
1
5
9
3
4
0
2
39
151
290
115
127
4
55
18
68
130
52
57
2
25
1
5
9
4
4
0
2
E:\FR\FM\12APN1.SGM
12APN1
15809
Federal Register / Vol. 83, No. 71 / Thursday, April 12, 2018 / Notices
TABLE 8—DISTANCES TO LEVELS A AND B HARASSMENT THRESHOLD CRITERIA FOR IMPACT AND VIBRATORY PILE
DRIVING AND PILE REMOVAL—Continued
Parameters
Level B ZOI radii (meters)
Piles per
day
Pile size and type
Drive method
36 inch steel .......
Proof Testing .....
2
Attenuation system
None ..................
160 dB
RMS
2,512
120 dB RMS
Level A ZOI radii (meters)
Lowfrequency
cetaceans
Midfrequency
cetaceans
Highfrequency
cetaceans
Phocid
pinnipeds
Otariid
pinnipeds
74
3
88
39
3
NA ......................
sradovich on DSK3GMQ082PROD with NOTICES
Sources: Sound levels from the Department’s Compendium of Pile Driving Sound Data (Department 2007). Distances were calculated using the NMFS-provided
companion User Spreadsheet, available at https://www.nmfs.noaa.gov/pr/acoustics/guidelines.htm.
The distance to the 120 dB rms Level
B Zone of Influence (ZOI) threshold for
vibratory pile driving was calculated to
be 10,000 meters for 24-inch (0.61meter) diameter steel pipe piles and
21,544 meters for 36-inch (0.91-meter)
diameter steel pipe piles. Previous
monitoring for the SFOBB Project has
shown background sound levels in the
active portions of the Bay, near the
project area, to range from 110 to 140 dB
rms, with typical background levels in
the range of 110 to 120 dB rms
(Department 2015). During previous
hydroacoustic monitoring for the
SFOBB Project, it has not been possible
to detect or distinguish sound from
vibratory pile driving beyond 1,000 to
2,000 meters (3,280 to 6,562 feet) from
the source (Rodkin 2009). Under all
previous IHAs for the SFOBB Project,
which included vibratory pile driving,
the ZOI for this activity has been set at
2,000 meters (6,562 feet) or less (NOAA
2016). Furthermore, it unlikely that
marine mammals in the Bay will detect
or show response to this sound at
distances greater than 2,000 meters
(6,562 feet), because of the background
sound levels in the Central Bay.
Therefore, the practical, applied ZOI for
the vibratory driving of 24-inch (0.61meter) and 36-inch (0.91-meter)
diameter steel pipe piles has been set at
2,000 meters (6,562 feet), as shown in
Table 7.
When NMFS Technical Guidance
(2016) was published, in recognition of
the fact that ensonified area/volume
could be more technically challenging
to predict because of the duration
component in the new thresholds, we
developed a User Spreadsheet that
includes tools to help predict a simple
isopleth that can be used in conjunction
with marine mammal density or
occurrence to help predict takes. We
note that because of some of the
assumptions included in the methods
used for these tools, we anticipate that
isopleths produced are typically going
to be overestimates of some degree,
which will result in some degree of
overestimate of Level A take. However,
these tools offer the best way to predict
appropriate isopleths when more
VerDate Sep<11>2014
19:20 Apr 11, 2018
Jkt 244001
sophisticated 3D modeling methods are
not available, and NMFS continues to
develop ways to quantitatively refine
these tools, and will qualitatively
address the output where appropriate.
For stationary sources pile driving,
NMFS User Spreadsheet predicts the
closest distance at which, if a marine
mammal remained at that distance the
whole duration of the activity, it would
not incur PTS. Inputs used in the User
Spreadsheet, and the resulting isopleths
are reported below in Table 8.
Marine Mammal Occurrence
In this section we provide the
information about the presence, density,
or group dynamics of marine mammals
that will inform the take calculations.
No systematic line transect surveys of
marine mammals have been performed
in the Bay. Therefore, the in-water
densities of harbor seals, California sea
lions, and harbor porpoises were
calculated based on 17 years of
observations during monitoring for the
SFOBB construction and demolition.
Care was taken to eliminate multiple
observations of the same animal,
although this can be difficult and is
likely that the same individual may
have been counted multiple times on
the same day. The amount of monitoring
performed per year varied, depending
on the frequency and duration of
construction activities with the
potential to affect marine mammals.
During the 257 days of monitoring from
2000 through 2017 (including 15 days of
baseline monitoring in 2003), 1,029
harbor seals, 83 California sea lions, and
24 harbor porpoises were observed in
waters in the project vicinity in total. In
2015, 2016, and 2017, the number of
harbor seals in the project area
increased significantly. In 2017, the
number of harbor porpoise in the project
area also increased significantly.
Therefore, a harbor seal density estimate
was calculated for 2015–2017, and a
harbor porpoise density estimate was
calculated for 2017, which may better
reflect the current use of the project area
by these animals. These observations
included data from baseline, pre-,
during, and post-pile driving,
mechanical dismantling, on-shore
PO 00000
Frm 00026
Fmt 4703
Sfmt 4703
blasting, and off-shore implosion
activities.
Insufficient sighting data exist to
estimate the density of bottlenose
dolphins. However, a single bottlenose
dolphin has been observed regularly,
south of the SFOBB east span since fall
2016. During monitoring performed in
2017 for the SFOBB, two bottlenose
dolphins were observed south of the
SFOBB.
Insufficient sighting data exist to
estimate elephant seal densities in the
Bay. Generally, only juvenile elephant
seals enter the Bay and do not remain
long. The most recent sighting near the
project area was in 2012, on the beach
at Clipper Cove on Treasure Island,
when a healthy yearling elephant seal
hauled out for approximately 1 day.
Approximately 100 juvenile northern
elephant seals strand in or near the Bay
each year, including individual
strandings at YBI and Treasure Island
(less than 10 strandings per year).
Insufficient sighting data exist to
estimate northern fur seal densities in
the Bay. Only two to four northern fur
seals strand in the Bay each year, and
they are unlikely to occur in the project
area.
The size of the areas monitored for
marine mammals has increased over the
17 years of observations. The majority of
pinniped monitoring has been focused
within a 610-meter (2,000-foot) radius of
the work area. Although some pinniped
observations have been recorded at
greater distances, in part because of
recent monitoring of larger areas for
harbor porpoise zones during pier
implosion, a 2-square-kilometer area,
corresponding with a 610-meter (2,000foot) radial distance, was used for
density calculations. Harbor porpoise
sightings in the Bay have increased in
recent years; however, the majority of
harbor porpoise observations made
during monitoring for the SFOBB
Project have been at distances ranging
from 2,438 to 3,048 meters (8,000 to
10,000 feet) from the work area.
Therefore, harbor porpoise densities
were calculated based on a 15-squarekilometer area, corresponding with a
2,438-meter (8,000-foot) radial distance,
with land areas subtracted from the
E:\FR\FM\12APN1.SGM
12APN1
15810
Federal Register / Vol. 83, No. 71 / Thursday, April 12, 2018 / Notices
area. Numbers used for density
calculations are shown in Table 9. In the
cases where densities were refined to
capture a narrower range of years to be
conservative, bold densities were used
for take calculations.
TABLE 9—ESTIMATED IN-WATER DENSITY OF MARINE MAMMAL SPECIES IN SFOBB AREA
Area of
monitoring
zone
(square
kilometer)
Species observed
Number of
animals
observed
Days of
monitoring
Density
animals/square
kilometer
Harbor seals, 2000–2017 ...............................
Harbor Seals, 2015–2017 ...............................
California Sea Lions, 2000–2017 ...................
Bottlenose Dolphins 2017 ...............................
2
2
2
2
257
47
257
6
1029
372
83
2
Harbor Porpoise, 2000–2017 ..........................
Harbor Porpoise, 2017 ....................................
Elephant Seal, 2000–2017 .............................
3
15
2
257
6
257
24
15
0
Northern Fur Seal, 2000–2017 .......................
2
257
0
Gray Whale, 2000–2017 .................................
2
257
0
2.002.
3.957.
0.161.
Insufficient
density.
0.031.
0.167.
Insufficient
density.
Insufficient
density.
Insufficient
density.
sighting data exists to estimate
sighting data exists to estimate
sighting data exists to estimate
sighting data exists to estimate
Notes:
Densities for Pacific harbor seals, California sea lions, and harbor porpoises are based on monitoring for the east span of the SFOBB from
2000 to 2017.
A second set of Pacific harbor seal densities were calculated from the increase in sightings recorded from 2015 to 2017.
A second set of harbor porpoise densities were calculated for the increase in sightings that were recorded in 2017.
Bold densities were used for take calculations.
Sources: Department 2001, 2004b, 2013b, 2013c, 2014, 2015b, 2016, 2017; Perlman 2017.
For species without enough sightings
to construct a density estimate, Caltrans
uses information based on group size
and frequency of sightings from
previous years of work to inform the
number of animals estimated to be
taken, which is detailed in the Take
Estimation section below.
Take Calculation and Estimation
Here we describe how the information
provided above is brought together to
produce a quantitative take estimate.
Take From Pier Implosion
The numbers of harbor seals, sea lions
and harbor porpoise that may be taken
by implosion of Piers E19 and E20 were
calculated based on distances to the
marine mammal threshold criteria,
duration of the activity, and the
estimated density of these species in the
ZOI.
The numbers of elephant seals,
northern fur seals and bottlenose
dolphin that may be taken by implosion
of Piers E19 and E20 were determined
based on distances to the marine
mammal threshold criteria, duration of
the activity, and sightings and
occurrence of these species in the Bay,
specifically near the project area.
Distances to marine mammal threshold
criteria were calculated based on the
highest sound pressure levels generated
during the previous pier implosion of
Piers E17 and E18 (two-pier implosion
event) . Gray whales were not
considered for pier implosion activities
as those activities will occur in late fall
and early winter, when gray whales are
not found in the Bay area.
The number of exposures of each
species was calculated over the entire
area of each Level A, Level B, and
mortality threshold criteria zone for the
proposed pier implosion event (Tables
10 through 12).
TABLE 10—LEVEL A PTS TAKE CALCULATIONS FOR IMPLOSION OF PIERS E19 AND E20
Species
Species
density
(animals/
square
kilometer)
sradovich on DSK3GMQ082PROD with NOTICES
Harbor Seal ..................
Sea Lion .......................
Harbor Porpoise ...........
Bottlenose Dolphin .......
Elephant Seal ...............
Fur Seal .......................
VerDate Sep<11>2014
19:20 Apr 11, 2018
3.957
0.161
0.167
NA
NA
NA
Jkt 244001
Species
density
(animals/
square
meters)
Level A ZOI
radii
(meters)
3.96E–06
1.61E–07
1.67E–07
NA
NA
NA
PO 00000
Frm 00027
70
30
290
40
70
30
Fmt 4703
Level A PTS
ZOI area
(square
meters)
Level A PTS
take
29462.347
9118.458
315798.484
5026.548
15393.804
2827.43
Sfmt 4703
E:\FR\FM\12APN1.SGM
0.1166
0.0015
0.0527
NA
NA
NA
12APN1
Number of
implosion
events
Level B take
calculated
1
1
1
1
1
1
0.1166
0.0015
0.0527
NA
NA
NA
15811
Federal Register / Vol. 83, No. 71 / Thursday, April 12, 2018 / Notices
TABLE 11—LEVEL B TTS TAKE CALCULATIONS FOR IMPLOSION OF PIERS E19 AND E20
Species
density
(animals/
square
kilometer)
Species
Harbor Seal ..................
Sea Lion .......................
Harbor Porpoise ...........
Bottlenose Dolphin .......
Elephant Seal ...............
Fur Seal .......................
Species
density
(animals/
square
meters)
3.957
0.161
0.167
NA
NA
NA
Level B TTS
ZOI area
(square
meters)
Level B ZOI
radii
(meters)
3.96E–06
1.61E–07
1.67E–07
NA
NA
NA
200
60
830
120
200
60
Number of pier
implosion
events
Level B TTS
take
164964.771
23434.268
2085701.996
45238.934
125663.706
11309.73
0.6528
0.0038
0.3483
NA
NA
NA
1
1
1
1
1
1
Level B take
calculated
0.6528
0.0038
0.3483
NA
NA
NA
TABLE 12—LEVEL B BEHAVIORAL TAKE CALCULATIONS FOR IMPLOSION OF PIERS E19 AND E20
Species
density
(animals/
square
kilometer)
Species
Harbor Seal ..................
Sea Lion .......................
Harbor Porpoise ...........
Bottlenose Dolphin .......
Elephant Seal ...............
Fur Seal .......................
Species
density
(animals/
square
meters)
3.957
0.161
0.167
NA
NA
NA
Level B
behavioral
ZOI area
(square
meters)
Level B ZOI
radii
(meters)
3.96E–06
1.61E–07
1.67E–07
NA
NA
NA
290
80
1,220
200
290
80
Level B
behavioral
take
315798.486
36118.343
4256937.444
125663.706
264207.942
20106.19
Number of pier
implosion
events
1.2496
0.0058
0.7109
NA
NA
NA
1
1
1
1
1
1
Level B take
calculated
1.2496
0.0058
0.7109
NA
NA
NA
TABLE 13—COMBINED ESTIMATED EXPOSURES OF MARINE MAMMALS TO THE PIER IMPLOSIONS FOR LEVELS A AND B,
AND MORTALITY THRESHOLD CRITERIA
Level A exposures 1
Level B exposures
for all implosions
Species
Behavioral
response
Temporary
threshold shift
Permanent
threshold
shift
Gastrointestinal
tract injury
Mortality 1
Slight lung
injury
Pacific Harbor Seal ..................................
California Sea Lion ..................................
Northern Elephant Seal ...........................
Northern Fur Seal ....................................
Bottlenose Dolphin ...................................
Harbor Porpoise .......................................
1
0
0
0
0
1
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Total ..................................................
2
1
0
0
0
0
Note:
1 No implosion will occur if any marine mammal is within the Level A or mortality threshold criteria zones.
Based on the distances to the marine
mammal threshold criteria and
estimated species density, it is not
expected that GI tract, lung injury, or
mortality could occur from the pier
implosion event. Approximately two
harbor seals (one by behavioral response
and one by TTS) and one harbor
porpoise (by behavioral response) may
be taken by Level B harassment during
the implosion Piers E19 and E20 (Table
12). No take of any other species is
anticipated.
The estimated number of marine
mammals to be exposed to implosion
SPLs for each threshold criteria (Table
13) are based on current density
estimates or occurrence of marine
mammals in the project area (Table 9
through 12). However, the number of
marine mammals in the area at any
given time is highly variable. Animal
movement depends on time of day, tide
levels, weather, and availability and
distribution of prey species. Therefore,
Caltrans requests the following number
of allowable harassment takes for each
Level B harassment criteria threshold
(Table 14).
sradovich on DSK3GMQ082PROD with NOTICES
TABLE 14—AMOUNT OF LEVEL B HARASSMENT TAKE REQUESTED FOR THE IMPLOSIONS OF PIERS E19 AND E20
Level B harassment take 1
Species
Behavioral
response
Pacific Harbor Seal ..................................................................................................................................................
California Sea Lion ..................................................................................................................................................
Northern Elephant Seal ...........................................................................................................................................
Northern Fur Seal ....................................................................................................................................................
Harbor Porpoise .......................................................................................................................................................
VerDate Sep<11>2014
19:20 Apr 11, 2018
Jkt 244001
PO 00000
Frm 00028
Fmt 4703
Sfmt 4703
E:\FR\FM\12APN1.SGM
12APN1
20
4
2
2
5
Temporary
threshold shift
10
3
1
1
5
15812
Federal Register / Vol. 83, No. 71 / Thursday, April 12, 2018 / Notices
TABLE 14—AMOUNT OF LEVEL B HARASSMENT TAKE REQUESTED FOR THE IMPLOSIONS OF PIERS E19 AND E20—
Continued
Level B harassment take 1
Species
Behavioral
response
Temporary
threshold shift
Bottlenose Dolphin ...................................................................................................................................................
4
2
Total ..................................................................................................................................................................
42
25
sradovich on DSK3GMQ082PROD with NOTICES
Note:
1 Pier implosion will be delayed if any marine mammals are detected within any of the Level A or mortality threshold criteria exclusion zones.
Pacific Harbor Seal: As discussed
above, harbor seal is the most numerous
marine mammal in the Bay. However,
take calculated based on species density
and the distances to the marine mammal
threshold criteria indicated that only
two harbor seals would be exposed to
sound pressure levels that can result in
Level B harassment (Table 13). One of
those exposures would be within the
Level B monitoring zone, and one
would be within the TTS zone (Table
13). Based on previous monitoring the
number of harbor seals in the water can
vary greatly, depending on weather
conditions or the availability of prey.
For example, during Pacific herring runs
further north in the Bay (near
Richardson Bay) in February 2014, very
few harbor seals were observed foraging
near YBI or transiting through the
project area for approximately 2 weeks.
Sightings went from a high of 27 harbor
seal individuals foraging or in transit in
one day to no seals per day in transit or
foraging through the project area
(Department 2014). In 2015 and 2016,
the number of harbor seal sighting in a
single day in the project area increased
up to 41 seals (Department 2015b,
2016). Because of this high degree of
variability, and the observation of up to
41 seals in the project area in a single
day Caltrans are requesting
authorization for the take of 30 harbor
seals by Level B harassment (20 by
Level B behavioral response and 10 by
Level B TTS) (Table 14).
California Sea Lion: As discussed
above, California sea lion is the second
most numerous marine mammal species
in the Bay, after the harbor seal.
However, take calculated based on
species density and the distances to the
marine mammal threshold criteria
indicated that no sea lions would be
exposed to sound pressure levels that
can result in Level B harassment (Table
13). Based on previous monitoring the
number of sea lions transiting through
or foraging in the project area can vary
greatly. Because of the high degree of
variability, regular observation of sea
lions in the project area, and because
this species may travel in groups
VerDate Sep<11>2014
19:20 Apr 11, 2018
Jkt 244001
Caltrans are requesting authorization for
the take of seven sea lions (four by Level
B behavioral response and three by
Level B TTS) (Table 14).
Harbor Porpoises: Based on the
calculated density estimates and the
distances to the marine mammal
threshold criteria, one harbor porpoise
(by behavioral response) may be taken
by Level B harassment during the
implosion of Piers E19 and E20 (Table
13). However the number of harbor
porpoise in the Bay and their foraging
range appears to be steadily increasing.
This high-frequency cetacean has a large
ZOI, because of its sensitivity to
anthropogenic sound. Further, this
species generally travels in either calf
cow pairs or small pods of four to five
porpoises. For these reasons Caltrans are
requesting authorization for the take of
10 harbor porpoise (five by Level B
behavioral response and five by Level B
TTS) (Table 14).
Northern Elephant Seal: As discussed
above, because of the infrequent
observation of this species in the Bay,
Caltrans estimates that no elephant seals
will be exposed to SPLs that can result
in Level B harassment (Table 13).
However, the number of elephant seals
that may enter and or strand in the Bay
in a given year is highly variable;
dependent on changes in oceanographic
conditions, effecting water temperature
and prey availability. Caltrans wants to
ensure that the project has coverage for
the incidental take of any species with
the potential to be present in the project
area. Therefore, Caltrans are requesting
authorization for the take of three
elephant seals (two by Level B
behavioral response and one by Level B
TTS) (Table 14).
Northern Fur Seal: As discussed
above, northern fur seals are found
infrequently in the Bay and are unlikely
to be in the vicinity of the pier
implosion. However, the number of fur
seals that may enter and or strand in the
Bay in a given year is highly variable;
dependent on changes in oceanographic
conditions, effecting water temperature
and prey availability. Caltrans wants to
ensure that the project has coverage for
PO 00000
Frm 00029
Fmt 4703
Sfmt 4703
the incidental take of any species with
the potential to be present in the project
area. Therefore, they are requesting
authorization for the take of three
northern fur seals (two by Level B
behavioral response and one by Level B
TTS) (Table 14).
Bottlenose Dolphin: As discussed
above, only small numbers of bottlenose
dolphin occur in the project vicinity.
Based on the low number of individuals
in the Bay and the distances to the
marine mammal threshold criteria
Caltrans anticipates that no bottlenose
dolphins would be exposed to SPLs that
can result in Level B harassment.
However, as discussed in Chapter 4,
until 2016, most bottlenose dolphins in
the Bay were observed in the western
Bay, from the Golden Gate Bridge to
Oyster Point and Redwood City,
although one individual was observed
frequently near the former Alameda Air
Station (Perlman 2017). As of 2017, the
same two individuals have been
observed regularly near Alameda
(Keener, pers. comm., 2017) and likely
pass by the project area. If additional
individuals begin using this eastern area
of the Bay, the number of bottlenose
sightings near the project area will
likely increase. Caltrans wants to ensure
that the project has coverage for the
incidental take of any species with the
potential to be present in the project
area. Therefore, they are requesting
authorization for the take of six
bottlenose dolphins (four by Level B
behavioral response and two by Level B
TTS) (Table 14).
Take From Pile Driving
The numbers of marine mammals by
species that may be taken by pile
driving were calculated based on
distance to the marine mammal
threshold criteria, days of driving, and
the estimated density of each species in
the ZOI, for the species that density
could be determined. The distances to
the relevant Level A and B zones are
listed above in Table 8. Because the
sizes of piles, types of piles, or
installation methods to be used are
unknown at this time, the take estimate
E:\FR\FM\12APN1.SGM
12APN1
15813
Federal Register / Vol. 83, No. 71 / Thursday, April 12, 2018 / Notices
has been prepared based on a worst case
scenario. The Level B take estimate is
based on 60 days of pile driving to
install 200 piles, 36 inches (0.91 meters)
in diameter, with a vibratory hammer,
as this results in the largest Level B zone
for a precautionary approach. The Level
species was calculated based on species
density (Table 9), for the species that
density could be determined, over the
entire area of each threshold criteria
zone as shown in Figures 14 and 15 in
the application. The numbers used for
take calculation are shown in Table 15.
A take estimate is based on 60 days of
pile driving to install 200 piles, 36
inches (0.91 meters) in diameter, with
an impact hammer, which has a larger
Level A zone than vibratory driving,
using of an air bubble curtain sound
attenuation system. The take of each
TABLE 15—ESTIMATED TAKE OF MARINE MAMMALS FROM PILE DRIVING AND PILE REMOVAL ACTIVITIES
Species
density
(animals/
square
kilometer)
Species
Species
density
(animals/
square
meters)
Level B
ZOI area
(square
meters)
Level B
ZOI radii
(meters)
Per day
take
Level B
Days of
pile driving
Level B take
calculated
Level B take
requested
Harbor Seal ...................................................
Sea Lion ........................................................
Harbor Porpoise ............................................
Bottlenose Dolphin ........................................
Elephant Seal ................................................
Gray Whale ...................................................
Fur Seal .........................................................
3.96
0.16
0.17
NA
NA
NA
NA
3.96E–06
1.61E–07
1.67E–07
NA
NA
NA
NA
2,000
2,000
2,000
2,000
2,000
2,000
2,000
9101027.61
9101027.61
9101027.61
9101027.61
9101027.61
9101027.61
9101027.61
36.01
1.47
1.52
NA
NA
NA
NA
60
60
60
60
60
60
60
2160.77
87.92
91.19
NA
NA
NA
NA
2161
88
91
30
23
4
12
Total Level B Take .................................
....................
....................
....................
........................
....................
....................
....................
2,392
Species
density
(animals/
square
kilometer)
Species
density
(animals/
square
meters)
Level A
ZOI radii
(meters)
Level A
ZOI area
(square
meters)
Per day
take
Level A
Days of
pile driving
Level A take
calculated
Level A take
requested 1
Species
3.96
0.16
0.17
NA
NA
NA
NA
3.96E–06
1.61E–07
1.67E–07
NA
NA
NA
NA
130
9
290
9
130
243
9
77907.73574
4302.570961
293195.3612
4302.570961
77907.73574
215669.2122
4302.570961
0.21
0.00
0.04
NA
NA
NA
NA
60
60
60
60
60
60
60
18.50
0.04
2.94
NA
NA
NA
NA
0
0
0
0
0
0
0
Total Level A Take 1 ..............................
sradovich on DSK3GMQ082PROD with NOTICES
Harbor Seal ...................................................
Sea Lion ........................................................
Harbor Porpoise ............................................
Bottlenose Dolphin ........................................
Elephant Seal ................................................
Gray Whale ...................................................
Fur Seal .........................................................
....................
....................
....................
........................
....................
....................
....................
0
Caltrans estimates a maximum of
2,392 instances of take by Level B
harassment may occur to seven stocks of
marine mammal during pile-driving
activities (Table 15). These individuals
will be exposed temporarily to
continuous (vibratory pile driving and
removal) sounds greater than 120 dB
rms and impulse (impact driving)
sounds greater than 160 dB rms. The
majority of the animals taken by Level
B harassment will be harbor seals (Table
15), the most numerous marine
mammals in the project area. Although
Level A take of marine mammals was
calculated based on distances to the
threshold, density of the species, and
duration of the activity; Caltrans does
not anticipate any individuals will be
taken by Level A harassment. With
proposed monitoring and establishment
of shutdown zones, discussed in the
Proposed Mitigation section below,
Caltrans proposes to avoid Level A
harassment of marine mammals.
The number of takes requested by
Caltrans are based on a calculation of
marine mammal density multiplied by
the daily isopleth multiplied by the
number of days of pile driving.
VerDate Sep<11>2014
19:20 Apr 11, 2018
Jkt 244001
However, due to variability in sightings
of northern elephant seal, northern fur
seal, bottlenose dolphin, and gray
whale, take estimates were adjusted
using species specific monitoring data
detailed below.
Northern Elephant Seal: Based on low
number of elephant seal sightings in the
project area, Caltrans anticipates that
very few if any elephant seals would be
exposed to continuous sounds greater
than 120 dB rms and impulse sounds
greater than 160 dB rms during pile
driving. No elephant seals have been
observed in the immediate project
vicinity. However, the number of
elephant seals that may enter and or
stand in the Bay in a given year is
highly variable; dependent of changes in
oceanographic conditions, effecting
water temperature and prey availability.
Further, the size of the Level B
harassment zone is large, extending
2,000 meters (6,562 feet) from the pile
driving site. Pile driving may take place
for up to 60 days and many of the
driving days would be consecutive.
Should an elephant seal or multiple
elephant seals be in the vicinity of the
project area for multiple days they could
PO 00000
Frm 00030
Fmt 4703
Sfmt 4703
be taken several times. To ensure
Caltrans has coverage for the incidental
take of any species with the potential to
be present in the project area, we are
proposing to authorize take of 12
elephant seals by Level B harassment
during pile driving activities (Table 15).
This equates to the take of one elephant
seal during 20 percent of the driving
days.
Northern fur seal: No fur seals have
been observed in the immediate project
vicinity. Should a fur seal or multiple
fur seals be in the vicinity of the project
area for multiple days they could be
taken several times. To ensure Caltrans
has necessary coverage for occasion fur
seals in the area, we propose to
authorize take of up to six northern fur
seals by Level B harassment during pile
driving activities (Table 15). This
equates to the take of one elephant seal
during 10 percent of the driving days.
Bottlenose dolphin: Only small
numbers of bottlenose dolphin occur in
the project vicinity. Until 2016, most
bottlenose dolphins in the Bay were
observed in the western Bay, from the
Golden Gate Bridge to Oyster Point and
Redwood City, although one individual
E:\FR\FM\12APN1.SGM
12APN1
15814
Federal Register / Vol. 83, No. 71 / Thursday, April 12, 2018 / Notices
was observed frequently near the former
Alameda Air Station (Perlman 2017). As
of 2017, the same two individuals have
been observed regularly near Alameda
(Keener, pers. comm., 2017) are likely
pass by the project area. If additional
individuals begin using this eastern area
of the Bay, the number of bottlenose
dolphin sightings near the project area
will likely increase. It is possible that
the same two resident bottlenose
dolphins and or additional individuals
could be taken multiple times during
the up to 60 days of pile driving.
Therefore, Caltrans is requesting
authorization for the take of 90
bottlenose dolphins by Level B
harassment during pile driving
activities. This equates to the take of 1.5
bottlenose dolphins during each day of
pile driving.
Gray whale: No gray whales have
been observed within 2,000 meters
(6,562 feet) of the project area, but they
have been observed just north of
Treasure Island and southwest of
Oakland Middle Harbor. According to
TMMC, two to six gray whales enter the
Bay each year in late winter through
spring (February through April),
presumably to feed. Caltrans wants to
ensure that the project has coverage for
the incidental take of any species with
the potential to be present in the project
area. Therefore, Caltrans is requesting
authorization for the take of 4 grey
whales by Level B harassment during
pile driving activities.
TABLE 16—COMBINED TOTAL TAKE REQUESTED FOR PIER IMPLOSION AND PILE-DRIVING ACTIVITIES
Pier implosion
Level B harassment take 1
Species
Temporary
threshold
shift
Behavioral
response
sradovich on DSK3GMQ082PROD with NOTICES
Pacific Harbor Seal ..............................................................
California Sea Lion ..............................................................
Northern Elephant Seal .......................................................
Northern Fur Seal ................................................................
Harbor Porpoise ...................................................................
Bottlenose Dolphin ...............................................................
Gray Whale ..........................................................................
Proposed Mitigation
In order to issue an IHA under
Section 101(a)(5)(D) of the MMPA,
NMFS must set forth the permissible
methods of taking pursuant to such
activity, and other means of effecting
the least practicable impact on such
species or stock and its habitat, paying
particular attention to rookeries, mating
grounds, and areas of similar
significance, and on the availability of
such species or stock for taking for
certain subsistence uses (latter not
applicable for this action). NMFS
regulations require applicants for
incidental take authorizations to include
information about the availability and
feasibility (economic and technological)
of equipment, methods, and manner of
conducting such activity or other means
of effecting the least practicable adverse
impact upon the affected species or
stocks and their habitat (50 CFR
216.104(a)(11)).
In evaluating how mitigation may or
may not be appropriate to ensure the
least practicable adverse impact on
species or stocks and their habitat, as
well as subsistence uses where
applicable, we carefully consider two
primary factors:
(1) The manner in which, and the
degree to which, the successful
implementation of the measure(s) is
expected to reduce impacts to marine
mammals, marine mammal species or
stocks, and their habitat. This considers
the nature of the potential adverse
VerDate Sep<11>2014
19:20 Apr 11, 2018
Jkt 244001
20
4
2
2
10
4
0
10
3
1
1
8
2
0
impact being mitigated (likelihood,
scope, range). It further considers the
likelihood that the measure will be
effective if implemented (probability of
accomplishing the mitigating result if
implemented as planned) the likelihood
of effective implementation (probability
implemented as planned); and
(2) the practicability of the measures
for applicant implementation, which
may consider such things as cost,
impact on operations, and, in the case
of a military readiness activity,
personnel safety, practicality of
implementation, and impact on the
effectiveness of the military readiness
activity.
Mitigation for Marine Mammals and
Their Habitat
Pier Implosions—The decision to
combine two smaller piers into single,
sequential blast events will further
reduce potential impacts on marine
mammals. This will allow faster
completion of the project and will
reduce the total number of pier
implosion events (days where pier
implosions occur).
BAS—As described previously in this
document, a BAS will be used around
both piers during the implosion. Based
on the results of acoustic monitoring for
the previous pier implosions, BAS
performance is anticipated to provide
approximately 70 to 80 percent
attenuation of implosion-related
pressure waves.
PO 00000
Frm 00031
Fmt 4703
Sfmt 4703
Pile driving
Level B
harassment
take 1
2,161
88
12
6
91
30
4
Total
Level B
harassment
take 1
2,191
95
15
9
109
36
4
Requested
take as
percent
of stock
abundance
7
.03
.01
.06
1.1
8
.02
Implosion shutdown zone—During
the implosion of Piers E19 and E20, a
project-specific monitoring plan will be
implemented to avoid the potential for
individual exposure to Level A
harassment, and to document the
number and species potentially exposed
to Level B harassment. This plan will be
similar to the Marine Foundation
Removal Project Final Biological
Monitoring Program, previously
approved by NMFS, that was
implemented during the implosions of
Piers E6 to E18. In particular, monitors
will observe the shutdown zone and
will delay the implosion if any
individuals are within this zone. The
same procedure was implemented
successfully for the implosions of Piers
E3 through E18, and no marine
mammals were exposed to SPLs above
the Level A or mortality threshold
criteria. This project-specific monitoring
plan will be transmitted to NMFS before
the implosions, for review and
concurrence.
Pile driving—All steel pipe piles
initially will be installed with a
vibratory hammer. The vibratory
hammer will be used to drive the
majority of the total pile lengths. In the
event that a pipe pile is installed
entirely with a vibratory hammer, it still
will be subject to final proof testing with
an impact hammer. A maximum of 10
percent of the piles installed completely
with a vibratory hammer may be prooftested with an impact hammer, without
E:\FR\FM\12APN1.SGM
12APN1
sradovich on DSK3GMQ082PROD with NOTICES
Federal Register / Vol. 83, No. 71 / Thursday, April 12, 2018 / Notices
the use of a marine pile-driving energy
attenuator. Proofing of piles will be
limited to a maximum of two piles per
day, for less than 1 minute per pile,
administering a maximum of 20 blows
per pile. Although both vibratory and
impact pile driving have the potential to
affect marine mammals, impact driving
is expected to generate higher SPLs.
Requiring the use of the vibratory
hammer will reduce the duration of
impact driving and potential exposure
to higher SPLs.
Pile driving energy attenuator—Use of
a marine pile-driving energy attenuator
(i.e., air bubble curtain system), or other
equally effective sound attenuation
method (e.g., dewatered cofferdam), will
be required by Caltrans during impact
driving of all steel pipe piles (with the
exception of pile proof-testing) and
during impact driving of 0.91-meter (36inch) diameter concrete piles. Requiring
the use of sound attenuation will reduce
SPLs and the size of the ZOIs for Level
A and Level B harassment.
Pile Driving Shutdown Zone—Before
the start of impact pile-driving
activities, the shutdown zones will be
established. The shutdown zones are
intended to include all areas where the
underwater SPLs are anticipated to
equal or exceed thresholds for injury—
PTS Level A harassment thresholds for
the specific species hearing groups,
shown in Table 3. NMFS-approved
observers will survey the shutdown
zones for 30 minutes before pile-driving
activities start. If marine mammals are
found within the shutdown zones, pile
driving will be delayed until the animal
has moved out of the shutdown zone,
either verified through sighting by an
observer or by waiting until enough
time has elapsed without a sighting, 15
minutes for pinnipeds and small
cetaceans (harbor porpoise and
bottlenose dolphin), and 30 minutes for
gray whale, to be able to assume that the
animal has moved beyond the zone.
With implementation of this avoidance
and minimization measure, exposure of
marine mammals to SPLs that can result
in PTS Level A harassment will be
avoided.
A 10 meter shutdown zone for all
marine mammals will also be
implemented for in-water heavy
machinery work that is not pile driving
or pier implosion. Similarly, if a marine
mammal for which take is not
authorized is seen within the
monitoring zone, operations will cease
until the animal is seen leaving the zone
or until 15 minutes have passed.
Based on our evaluation of the
applicant’s proposed measures, NMFS
has preliminarily determined that the
proposed mitigation measures provide
VerDate Sep<11>2014
19:20 Apr 11, 2018
Jkt 244001
the means effecting the least practicable
impact on the affected species or stocks
and their habitat, paying particular
attention to rookeries, mating grounds,
and areas of similar significance.
Proposed Monitoring and Reporting
In order to issue an IHA for an
activity, Section 101(a)(5)(D) of the
MMPA states that NMFS must set forth,
requirements pertaining to the
monitoring and reporting of such taking.
The MMPA implementing regulations at
50 CFR 216.104(a)(13) indicate that
requests for authorizations must include
the suggested means of accomplishing
the necessary monitoring and reporting
that will result in increased knowledge
of the species and of the level of taking
or impacts on populations of marine
mammals that are expected to be
present in the proposed action area.
Effective reporting is critical both to
compliance as well as ensuring that the
most value is obtained from the required
monitoring.
Monitoring and reporting
requirements prescribed by NMFS
should contribute to improved
understanding of one or more of the
following:
• Occurrence of marine mammal
species or stocks in the area in which
take is anticipated (e.g., presence,
abundance, distribution, density);
• Nature, scope, or context of likely
marine mammal exposure to potential
stressors/impacts (individual or
cumulative, acute or chronic), through
better understanding of: (1) Action or
environment (e.g., source
characterization, propagation, ambient
noise); (2) affected species (e.g., life
history, dive patterns); (3) co-occurrence
of marine mammal species with the
action; or (4) biological or behavioral
context of exposure (e.g., age, calving or
feeding areas);
• Individual marine mammal
responses (behavioral or physiological)
to acoustic stressors (acute, chronic, or
cumulative), other stressors, or
cumulative impacts from multiple
stressors;
• How anticipated responses to
stressors impact either: (1) Long-term
fitness and survival of individual
marine mammals; or (2) populations,
species, or stocks;
• Effects on marine mammal habitat
(e.g., marine mammal prey species,
acoustic habitat, or other important
physical components of marine
mammal habitat); and
• Mitigation and monitoring
effectiveness.
PO 00000
Frm 00032
Fmt 4703
Sfmt 4703
15815
Visual Marine Mammal Observations
Caltrans will collect sighting data and
behavioral responses to construction for
marine mammal species observed in the
region of activity during the period of
activity. All protected species observers
(PSOs) will be trained in marine
mammal identification and behaviors
and are required to have no other
construction-related tasks while
conducting monitoring. A minimum of
two PSOs will be required for all pile
driving activities. Caltrans will establish
shutdown zones, similar to those
detailed in Table 8, as well as a
monitoring zone of 2,000 meters for all
marine mammals. Caltrans will monitor
the shutdown zone and monitoring zone
30 minutes before, during, and 30
minutes after pile driving, with
observers located at the best practicable
vantage points. Based on our
requirements, Caltrans would
implement the following procedures for
pile driving:
• PSOs would be located at the best
vantage point(s) in order to properly see
the entire shutdown zone and as much
of the disturbance zone as possible;
• During all observation periods,
observers will use binoculars and the
naked eye to search continuously for
marine mammals;
• If the shutdown zones are obscured
by fog or poor lighting conditions, pile
driving at that location will not be
initiated until that zone is visible.
Should such conditions arise while
impact driving is underway, the activity
would be halted; and
• The shutdown zone and observable
portion of the monitoring zone around
the pile will be monitored for the
presence of marine mammals 30 min
before, during, and 30 min after any pile
driving activity.
Data Collection
We require that observers use
approved data forms. Among other
pieces of information, Caltrans will
record detailed information about any
implementation of shutdowns,
including the distance of animals to the
pile and description of specific actions
that ensued and resulting behavior of
the animal, if any. In addition, Caltrans
will attempt to distinguish between the
number of individual animals taken and
the number of incidences of take. We
require that, at a minimum, the
following information be collected on
the sighting forms:
• Date and time that monitored
activity begins or ends;
• Construction activities occurring
during each observation period;
• Weather parameters (e.g., percent
cover, visibility);
E:\FR\FM\12APN1.SGM
12APN1
15816
Federal Register / Vol. 83, No. 71 / Thursday, April 12, 2018 / Notices
• Water conditions (e.g., sea state,
tide state);
• Species, numbers, and, if possible,
sex and age class of marine mammals;
• Description of any observable
marine mammal behavior patterns,
including bearing and direction of
travel, and if possible, the correlation to
SPLs;
• Distance from pile driving activities
to marine mammals and distance from
the marine mammals to the observation
point;
• Description of implementation of
mitigation measures (e.g., shutdown or
delay);
• Locations of all marine mammal
observations; and
• Other human activity in the area.
sradovich on DSK3GMQ082PROD with NOTICES
Reporting
A draft report would be submitted to
NMFS within 90 days of the completion
of marine mammal monitoring, or 60
days prior to the requested date of
issuance of any future IHA for projects
at the same location, whichever comes
first. The report will include marine
mammal observations pre-activity,
during-activity, and post-activity during
pile driving days, and will also provide
descriptions of any behavioral responses
to construction activities by marine
mammals and a complete description of
all mitigation shutdowns and the results
of those actions and an extrapolated
total take estimate based on the number
of marine mammals observed during the
course of construction. A final report
must be submitted within 30 days
following resolution of comments on the
draft report.
Negligible Impact Analysis and
Determination
NMFS has defined negligible impact
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
(50 CFR 216.103). A negligible impact
finding is based on the lack of likely
adverse effects on annual rates of
recruitment or survival (i.e., populationlevel effects). An estimate of the number
of takes alone is not enough information
on which to base an impact
determination. In addition to
considering estimates of the number of
marine mammals that might be ‘‘taken’’
through harassment, NMFS considers
other factors, such as the likely nature
of any responses (e.g., intensity,
duration), the context of any responses
(e.g., critical reproductive time or
location, migration), as well as effects
on habitat, and the likely effectiveness
VerDate Sep<11>2014
19:20 Apr 11, 2018
Jkt 244001
of the mitigation. We also assess the
number, intensity, and context of
estimated takes by evaluating this
information relative to population
status. Consistent with the 1989
preamble for NMFS’s implementing
regulations (54 FR 40338; September 29,
1989), the impacts from other past and
ongoing anthropogenic activities are
incorporated into this analysis via their
impacts on the environmental baseline
(e.g., as reflected in the regulatory status
of the species, population size and
growth rate where known, ongoing
sources of human-caused mortality, or
ambient noise levels).
Pile driving and pier implosion
activities associated from the Caltrans
project, as outlined previously, have the
potential to disturb or displace marine
mammals. Specifically, the specified
activities may result in take, in the form
of Level B harassment (TTS and
behavioral disturbance), from
underwater sounds generated from pier
implosions and pile driving. Potential
takes could occur if individuals of these
species are present in the ensonified
zone when pile driving or implosion
occurs. A few marine mammals could
experience TTS if they occur within the
Level B TTS zone. However, TTS is a
temporary loss of hearing sensitivity
when exposed to loud sound, and the
hearing threshold is expected to recover
completely within minutes to hours.
Therefore, it is not considered an injury.
In addition, even if an animal receives
a TTS, the TTS would be a one-time
event from a brief impulse noise (about
5 seconds), making it unlikely that the
TTS would lead to PTS. If an animal
undergoes a TTS from pier implosion, it
is likely to recover quickly as there is
only one implosion event proposed.
Finally, there is no critical habitat or
other biologically important areas in the
vicinity of Caltrans’ proposed controlled
implosion areas (Calambokidis et al.,
2015).
No serious injury or mortality is
anticipated given the nature of the
activities and measures designed to
minimize the possibility of injury to
marine mammals. The potential for
these outcomes is minimized through
the construction method and the
implementation of the planned
mitigation measures. Specifically,
Caltrans proposes to use a blast
attenuation system for the pier
implosion, which it has previously used
successfully. For pile driving activities,
vibratory and impact hammers will be
the primary methods of pier installation.
Impact pile driving produces short,
sharp pulses with higher peak levels
and much sharper rise time to reach
those peaks. If impact driving is
PO 00000
Frm 00033
Fmt 4703
Sfmt 4703
necessary, implementation of soft start
and shutdown zones significantly
reduces any possibility of injury. Given
sufficient ‘‘notice’’ through use of soft
start (for impact driving), marine
mammals are expected to move away
from a sound source that is annoying
prior to it becoming potentially
injurious. Caltrans will use a minimum
of two PSOs stationed strategically to
increase detectability of marine
mammals, enabling a high rate of
success in implementation of
shutdowns to avoid injury.
Caltrans’ proposed activities are
localized and of relatively short
duration (June to November). This
duration does not overlap with
breeding, pupping, or other biologically
significant events for marine mammal
species in the area. The project area is
also very limited in scope spatially, as
all work is concentrated on the edges of
a single bridge expanse. These localized
and short-term noise exposures may
cause short-term behavioral
modifications in seven marine mammal
species. Moreover, the proposed
mitigation and monitoring measures are
expected to further reduce the
likelihood of injury, as it is unlikely an
animal would remain in close proximity
to the sound source with small Level A
isopleths. While the project area is
known to be frequented by harbor seals
and California sea lions, it is not an
established breeding ground for local
populations.
The project also is not expected to
have significant adverse effects on
affected marine mammals’ habitat. The
project activities would not modify
existing marine mammal habitat for a
significant amount of time. The
activities may cause some fish to leave
the area of disturbance, thus temporarily
impacting marine mammals’ foraging
opportunities in a limited portion of the
foraging range. However, because of the
short duration of the activities and the
relatively small area of the habitat that
may be affected, and the decreased
potential of prey species to be in the
Project area during the construction
work window, the impacts to marine
mammal habitat are not expected to
cause significant or long-term negative
consequences.
Effects on individuals that are taken
by Level B harassment, on the basis of
reports in the literature as well as
monitoring from other similar activities,
will likely be limited to temporary
reactions such as increased swimming
speeds, increased surfacing time,
flushing, or decreased foraging (if such
activity were occurring) (e.g., Thorson
and Reyff 2006; Lerma 2014). Most
likely, individuals will simply move
E:\FR\FM\12APN1.SGM
12APN1
Federal Register / Vol. 83, No. 71 / Thursday, April 12, 2018 / Notices
sradovich on DSK3GMQ082PROD with NOTICES
away from the sound source and be
temporarily displaced from the areas of
pile driving and implosions. Thus, even
repeated Level B harassment of some
small subset of the overall stock is
unlikely to result in any significant
realized decrease in fitness for the
affected individuals, and thus would
not result in any adverse impact to the
stock as a whole. For some stocks, such
as harbor seal, more animal presence
has increased in recent years, despite
Caltrans’ work in the area.
In summary and as described above,
the following factors primarily support
our preliminary determination that the
impacts resulting from this activity are
not expected to adversely affect the
species or stock through effects on
annual rates of recruitment or survival:
• No mortality is anticipated or
authorized;
• No more than 10 individuals per
species are expected to incur TTS
during pier implosion. No TTS is
expected to occur during pile driving.
The size of the zones in which TTS is
expected to occur are small and will be
heavily monitored per the measures
outlined above in the Proposed
Monitoring section;
• Level B harassment may consist of
temporary modifications in behavior
(e.g. temporary avoidance of habitat or
changes in behavior);
• The lack of important feeding,
pupping, or other biologically
significant areas in the action area
during the construction window;
• The small impact area relative to
species range size;
• Mitigation is expected to minimize
the likelihood and severity of the level
of harassment; and
• The small percentage of the stock
that may be affected by project activities
(< eight percent for all stocks).
Based on the analysis contained
herein of the likely effects of the
specified activity on marine mammals
and their habitat, and taking into
consideration the implementation of the
proposed monitoring and mitigation
measures, NMFS preliminarily finds
that the total marine mammal take from
the proposed activity will have a
negligible impact on all affected marine
mammal species or stocks.
Small Numbers
As noted above, only small numbers
of incidental take may be authorized
under Section 101(a)(5)(D) of the MMPA
for specified activities other than
military readiness activities. The MMPA
does not define small numbers and so,
in practice, where estimated numbers
are available, NMFS compares the
number of individuals taken to the most
VerDate Sep<11>2014
19:20 Apr 11, 2018
Jkt 244001
appropriate estimation of abundance of
the relevant species or stock in our
determination of whether an
authorization is limited to small
numbers of marine mammals.
Additionally, other qualitative factors
may be considered in the analysis, such
as the temporal or spatial scale of the
activities.
Table 16 above details the number of
individuals that could be exposed to
received noise levels that could cause
TTS or Level B harassment for the
proposed work at the project site
relative to the total stock abundance.
The numbers of animals authorized to
be taken for all species would be
considered small relative to the relevant
stocks or populations even if each
estimated instance of take occurred to a
new individual. The total percent of the
population (if each instance was a
separate individual) for which take is
requested is less than eight percent for
all stocks (Table 16). Based on the
analysis contained herein of the
proposed activity (including the
proposed mitigation and monitoring
measures) and the anticipated take of
marine mammals, NMFS preliminarily
finds that small numbers of marine
mammals will be taken relative to the
population size of the affected species
or stocks.
Unmitigable Adverse Impact Analysis
and Determination
There are no relevant subsistence uses
of the affected marine mammal stocks or
species implicated by this action.
Therefore, NMFS has preliminarily
determined that the total taking of
affected species or stocks would not
have an unmitigable adverse impact on
the availability of such species or stocks
for taking for subsistence purposes.
Endangered Species Act (ESA)
Section 7(a)(2) of the Endangered
Species Act of 1973 (ESA: 16 U.S.C.
1531 et seq.) requires that each Federal
agency insure that any action it
authorizes, funds, or carries out is not
likely to jeopardize the continued
existence of any endangered or
threatened species or result in the
destruction or adverse modification of
designated critical habitat. To ensure
ESA compliance for the issuance of
IHAs, NMFS consults internally, in this
case with the West Coast Region
Protected Resources Division Office,
whenever we propose to authorize take
for endangered or threatened species.
No incidental take of ESA-listed
species is proposed for authorization or
expected to result from this activity.
Therefore, NMFS has determined that
PO 00000
Frm 00034
Fmt 4703
Sfmt 4703
15817
formal consultation under section 7 of
the ESA is not required for this action.
Proposed Authorization
As a result of these preliminary
determinations, NMFS proposes to issue
an IHA to Caltrans for conducting pier
implosion and pile driving activity at
the San Francisco-Oakland Bay Bridge
from May 2018–April 2019, provided
the previously mentioned mitigation,
monitoring, and reporting requirements
are incorporated. This section contains
a draft of the IHA itself. This section
contains a draft of the IHA itself. The
wording contained in this section is
proposed for inclusion in the IHA (if
issued).
1. This Incidental Harassment
Authorization (IHA) is valid for 1 year
from May 15, 2018 through April 14,
2019.
2. This IHA is valid only for pier
implosion and pile driving activities
associated with the San Francisco—
Oakland Bay Bridge.
3. General Conditions
(a) A copy of any issued LOA or IHA
must be in the possession of the
applicant, its designees, and work crew
personnel operating under the authority
of the issued LOA.
(b) The species authorized for taking
are summarized in Table 17.
(c) The taking, by Level B harassment
only, is limited to the species listed in
condition 3(b). See Table 17 for
numbers of take authorized.
TABLE 17—AUTHORIZED TAKE
NUMBERS
Species
Pacific Harbor Seal ...............
California Sea Lion ...............
Northern Elephant Seal ........
Northern Fur Seal .................
Harbor Porpoise ...................
Bottlenose Dolphin ...............
Gray Whale ...........................
Total
Level B
harassment
take
2,161
88
12
6
91
30
4
(d) The taking by injury (Level A
harassment), serious injury, or death of
the species listed in condition 3(c) of
the Authorization or any taking of any
other species of marine mammal is
prohibited and may result in the
modification, suspension, or revocation
of this IHA, unless authorization of take
by Level A harassment is listed in
condition 3(b) of this Authorization.
4. Mitigation Measures
The holder of this Authorization is
required to implement the following
mitigation measures.
(a) In-water pile driving and pile
removal activities and the controlled
E:\FR\FM\12APN1.SGM
12APN1
15818
Federal Register / Vol. 83, No. 71 / Thursday, April 12, 2018 / Notices
implosion of Piers E19 and E20 shall
only be conducted during daylight
hours and with enough time for pre and
post activity monitoring, and with good
visibility when the largest exclusion
zone can be visually monitored.
(b) For controlled implosion of Piers
E19 and E20, Caltrans shall install and
use a Blast Attenuation System (BAS)
prior to demolition to reduce the
shockwave from the implosion.
(c) Establishment of shutdown zones
(i) For in-water heavy machinery
work (such as debris removal or setting
up the BAS), a minimum 10 m
shutdown zone shall be implemented. If
a marine mammal comes within 10 m of
such operations, operations shall cease
and vessels shall reduce speed to the
minimum level required to maintain
steerage and safe working conditions.
This type of work could include (but is
not limited to) the following activities:
(1) Vibratory pile driving; (2) movement
of the barge to the pile location; (3)
positioning of the pile on the substrate
via a crane (i.e., stabbing the pile); (4)
removal of the pile from the water
column/substrate via a crane (i.e.,
deadpull); or (5) the placement of sound
attenuation devices around the piles.
(ii) For controlled implosion and
associated test blasting, as well as pile
driving, Caltrans shall establish
monitoring zones that are appropriate to
specific marine mammal functional
hearing groups for each implosion
scenario (See Tables 18 & 19 below).
TABLE 18—SHUTDOWN AND MONITORING ZONES FOR PIER IMPLOSIONS
Species/group
Level B behavioral response
monitoring zone
Level B TTS
monitoring zone
Level A injury and mortality
exclusion zone
Pinniped and Dolphin .......................................
Harbor Porpoise ................................................
290 meters (951 feet) .............
1,220 meters (4,003 feet) .......
200 meters (656 feet) .............
830 meters (2,723 feet) ..........
70 meters (230 feet).
290 meters (951 feet).
TABLE 19—SHUTDOWN AND MONITORING ZONES FOR PILE DRIVING
Installation
method
Attenuation
system
Level A pinniped and
dolphin exclusion zone
Level A porpoise and
whale exclusion zone
H-Pile ...........................
24-inch Steel Pipe Pile
36-inch Steel Pipe Pile
H-Pile ...........................
24-inch Steel Pipe Pile
36-inch Steel Pipe Pile
24-inch Concrete Pile ..
36-inch Concrete Pile ..
sradovich on DSK3GMQ082PROD with NOTICES
Pile type
Vibratory .............
Vibratory .............
Vibratory .............
Impact .................
Impact .................
Impact .................
Impact .................
Impact .................
None ...................
None ...................
None ...................
None ...................
Bubble Curtain ....
Bubble Curtain ....
None ...................
Bubble Curtain ....
2 meters (7 feet) ........
8 meters (26 feet) ......
20 meters (98 feet) ....
18 meters (59 feet) ....
68 meters (223 feet) ..
130 meters (427 feet)
52 meters (171 feet) ..
57 meters (187 feet) ..
1 meter (3 feet) ..........
19 meters (62 feet) ....
49 meters (161 feet) ..
39 meters (128 feet) ..
151 meters (495 feet)
290 meters (951 feet)
115 meters (377 feet)
127 meters (417 feet)
(d) Shutdown Zone Monitoring for
Mitigation Measures
(i) Pre-activity monitoring shall take
place from 30 minutes prior to initiation
of activity and post-activity monitoring
shall continue through 30 minutes postcompletion for construction activity and
60 minutes post-completion for
implosion activity. Pile driving may
commence at the end of the 30-minute
pre-activity monitoring period, provided
observers have determined that the
shutdown zone is clear of marine
mammals, which includes delaying start
of pile driving activities if a marine
mammal is sighted in the zone, as
described in Table 19 above.
(ii) A determination that the
shutdown zone is clear must be made
during a period of good visibility (i.e.,
the entire shutdown zone and
surrounding waters must be visible to
the naked eye).
(iii) If a marine mammal approaches
or enters the shutdown zone during
activities or pre-activity monitoring, all
pile driving or implosion activities at
that location shall be halted or delayed,
respectively. If activity is halted or
delayed due to the presence of a marine
mammal, the activity may not resume or
commence until either the animal has
VerDate Sep<11>2014
19:20 Apr 11, 2018
Jkt 244001
voluntarily left and been visually
confirmed beyond the shutdown zone
and 30 minutes have passed without redetection of the animal. Pile driving
activities include the time to install or
remove a single pile or series of piles,
as long as the time elapsed between uses
of the pile driving equipment is no more
than thirty minutes.
(iv) Caltrans shall use soft start
techniques when impact pile driving.
Soft start requires contractors to provide
an initial set of strikes at reduced
energy, followed by a thirty-second
waiting period, then two subsequent
reduced energy strike sets. Soft start
shall be implemented at the start of each
day’s impact pile driving and at any
time following cessation of impact pile
driving for a period of thirty minutes or
longer.
(v) If the number of authorized takes
are reached, Caltrans will shut down if
a marine mammal is sighted within or
approaching the monitoring zone.
(vi) If a species for which take is not
authorized is sighted within or
approaching the monitoring zone,
Caltrans will shut down.
5. Monitoring
(i) The holder of this Authorization is
required to conduct marine mammal
monitoring during pier implosion and
PO 00000
Frm 00035
Fmt 4703
Sfmt 4703
Level B monitoring zone—
all species
1,000 meters (3,280 feet).
2,000 meters (6,562 feet).
2,000 meters (6,562 feet).
100 meters (328 feet).
215 meters (705 feet).
541 meters (1,775 feet).
46 meters (151 feet).
117 meters (384 feet).
pile driving and removal activities.
Marine mammal monitoring and
reporting shall be conducted in
accordance with the monitoring
measures in the application.
(a) For all pile driving activities, a
minimum of two protected species
observer (PSOs) shall be required, with
at least one PSO stationed at the active
pile driving rig or at the best vantage
point(s) practicable to monitor the
shutdown zone for marine mammals
and implement shutdown or delay
procedures when applicable through
communication with the equipment
operator. Other PSOs should be
stationed at the best vantage point(s)
practicable to observe the monitoring
zone.
(b) For all pier implosion activities, a
minimum of eight PSOs will be
required. One PSO will be designated as
the Lead PSO, who will receive updates
from other PSOs on the presence or
absence of marine mammals within the
PSO. This Lead PSO will notify the
Environmental Compliance Manager of
a cleared shutdown zone before the start
of the implosion(s). PSOs shall be
positioned near the edge of each of the
threshold criteria zones and shall utilize
E:\FR\FM\12APN1.SGM
12APN1
sradovich on DSK3GMQ082PROD with NOTICES
Federal Register / Vol. 83, No. 71 / Thursday, April 12, 2018 / Notices
boats, barges, and bridge piers and
roadway.
(ii) Caltrans shall conduct briefings
for construction supervisors and crews,
the monitoring team, and Caltrans staff
prior to the start of all pile driving
activity, and when new personnel join
the work, in order to explain
responsibilities, communication
procedures, the marine mammal
monitoring protocol, and operational
procedures.
(iii) Monitoring of pile driving shall
be conducted by qualified PSOs (see
below), who shall have no other
assigned tasks during monitoring
periods. Caltrans shall adhere to the
following conditions when selecting
observers:
• Independent PSOs shall be used
(i.e., not construction personnel);
• At least one PSO must have prior
experience working as a marine
mammal observer during construction
activities;
• Other PSOs may substitute
education (degree in biological science
or related field) or training for
experience;
• Where a team of three or more PSOs
are required, a lead observer or
monitoring; coordinator shall be
designated. The lead observer must have
prior experience working as a marine
mammal observer during construction;
and
• Caltrans shall submit PSO CVs for
approval by NMFS;
Caltrans shall ensure that observers
have the following additional
qualifications:
• Ability to conduct field
observations and collect data according
to assigned protocols;
• Experience or training in the field
identification of marine mammals,
including the identification of
behaviors;
• Sufficient training, orientation, or
experience with the construction
operation to provide for personal safety
during observations;
• Writing skills sufficient to prepare a
report of observations including but not
limited to the number and species of
marine mammals observed; dates and
times when in-water construction
activities were conducted; dates, times,
and reason for implementation of
mitigation (or why mitigation was not
implemented when required); and
marine mammal behavior; and
• Ability to communicate orally, by
radio or in person, with project
personnel to provide real-time
information on marine mammals
observed in the area as necessary.
(iv) If a species for which
authorization has not been granted, or a
VerDate Sep<11>2014
19:20 Apr 11, 2018
Jkt 244001
species for which authorization has
been granted but the authorized takes
are met, is observed approaching or
within the monitoring zone (2,000 m),
activities must shut down immediately
using delay and shut-down procedures.
Activities must not resume until the
animal has been confirmed to have left
the area or the observation time period
has elapsed.
6. Reporting
(i) Caltrans shall submit a draft report
to NMFS [not later than 90 days
following the end of construction
activities OR 60 days prior to the
issuance of any subsequent IHA for the
project]. Caltrans shall provide a final
report within 30 days following
resolution of NMFS’ comments on the
draft report. Reports shall contain, at
minimum, the following:
• Date and time that monitored
activity begins and ends for each day
conducted (monitoring period);
• Construction activities occurring
during each daily observation period,
including how many and what type of
piles driven;
• Deviation from initial proposal in
pile numbers, pile types, average
driving times, etc.;
• Weather parameters in each
monitoring period (e.g., wind speed,
percent cloud cover, visibility);
• Water conditions in each
monitoring period (e.g., sea state, tide
state);
• For each marine mammal sighting:
Æ Species, numbers, and, if possible,
sex and age class of marine mammals;
Æ Description of any observable
marine mammal behavior patterns,
including bearing and direction of travel
and distance from pile driving activity;
Æ Location and distance from pile
driving activities to marine mammals
and distance from the marine mammals
to the observation point; and
Æ Estimated amount of time that the
animals remained in the Level B zone;
• Description of implementation of
mitigation measures within each
monitoring period (e.g., shutdown or
delay);
• Other human activity in the area
within each monitoring period
• A summary of the following:
Æ Total number of individuals of each
species detected within the Level B
Zone, and estimated as taken if
correction factor appropriate;
Æ Total number of individuals of each
species detected within the Level A
Zone and the average amount of time
that they remained in that zone; and
Æ Daily average number of
individuals of each species
(differentiated by month as appropriate)
detected within the the Level B Zone,
and estimated as taken, if appropriate.
PO 00000
Frm 00036
Fmt 4703
Sfmt 4703
15819
(ii) In the unanticipated event that the
specified activity clearly causes the take
of a marine mammal in a manner
prohibited by this IHA, such as a serious
injury or mortality, Caltrans shall
immediately cease the specified
activities and report the incident to the
Office of Protected Resources, NMFS,
and the West Coast Regional Stranding
Coordinator. The report must include
the following information:
a. Time and date of the incident;
b. Description of the incident;
c. Environmental conditions (e.g.,
wind speed and direction, Beaufort sea
state, cloud cover, and visibility);
d. Description of all marine mammal
observations in the 24 hours preceding
the incident;
e. Species identification or
description of the animal(s) involved;
f. Fate of the animal(s); and
g. Photographs or video footage of the
animal(s).
(iii) Activities shall not resume until
NMFS is able to review the
circumstances of the prohibited take.
NMFS will work with Caltrans to
determine what measures are necessary
to minimize the likelihood of further
prohibited take and ensure MMPA
compliance. Caltrans may not resume
their activities until notified by NMFS.
(iv) In the event that the Caltrans
discovers an injured or dead marine
mammal, and the lead observer
determines that the cause of the injury
or death is unknown and the death is
relatively recent (e.g., in less than a
moderate state of decomposition),
Caltrans shall immediately report the
incident to the Office of Protected
Resources, NMFS, and the West Coast
Regional Stranding Coordinator.
The report must include the same
information identified above. Activities
may continue while NMFS reviews the
circumstances of the incident. NMFS
will work with Caltrans to determine
whether additional mitigation measures
or modifications to the activities are
appropriate.
(v) In the event that Caltrans discovers
an injured or dead marine mammal, and
the lead observer determines that the
injury or death is not associated with or
related to the activities authorized in the
IHA (e.g., previously wounded animal,
carcass with moderate to advanced
decomposition, scavenger damage),
Caltrans shall report the incident to the
Office of Protected Resources, NMFS,
and the West Coast Regional Stranding
Coordinator, NMFS, within 24 hours of
the discovery. Caltrans shall provide
photographs or video footage or other
documentation of the stranded animal
sighting to NMFS.
E:\FR\FM\12APN1.SGM
12APN1
15820
Federal Register / Vol. 83, No. 71 / Thursday, April 12, 2018 / Notices
7. This Authorization may be
modified, suspended or withdrawn if
the holder fails to abide by the
conditions prescribed herein, or if
NMFS determines the authorized taking
is having more than a negligible impact
on the species or stock of affected
marine mammals.
sradovich on DSK3GMQ082PROD with NOTICES
Request for Public Comments
We request comment on our analyses,
the proposed authorization, and any
other aspect of this Notice of Proposed
IHA for the proposed pier implosion
and pile driving. We also request
comment on the potential for renewal of
this proposed IHA as described in the
paragraph below. Please include with
your comments any supporting data or
literature citations to help inform our
final decision on the request for MMPA
authorization.
On a case-by-case basis, NMFS may
issue a second one-year IHA without
additional notice when (1) another year
of identical or nearly identical activities
as described in the Specified Activities
section is planned or (2) the activities
would not be completed by the time the
IHA expires and a second IHA would
allow for completion of the activities
beyond that described in the Dates and
Duration section, provided all of the
following conditions are met:
• A request for renewal is received no
later than 60 days prior to expiration of
the current IHA;
• The request for renewal must
include the following:
(1) An explanation that the activities
to be conducted beyond the initial dates
either are identical to the previously
analyzed activities or include changes
so minor (e.g., reduction in pile size)
that the changes do not affect the
previous analyses, take estimates, or
mitigation and monitoring
requirements; and
(2) A preliminary monitoring report
showing the results of the required
monitoring to date and an explanation
showing that the monitoring results do
not indicate impacts of a scale or nature
not previously analyzed or authorized;
and
• Upon review of the request for
renewal, the status of the affected
species or stocks, and any other
pertinent information, NMFS
determines that there are no more than
minor changes in the activities, the
mitigation and monitoring measures
remain the same and appropriate, and
the original findings remain valid.
VerDate Sep<11>2014
19:20 Apr 11, 2018
Jkt 244001
Dated: April 9, 2018.
Donna S. Wieting,
Director, Office of Protected Resources,
National Marine Fisheries Service.
[FR Doc. 2018–07573 Filed 4–11–18; 8:45 am]
BILLING CODE 3510–22–P
DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric
Administration
RIN 0648–XG149
Magnuson-Stevens Act Provisions;
General Provisions for Domestic
Fisheries; Application for Exempted
Fishing Permits
National Marine Fisheries
Service (NMFS), National Oceanic and
Atmospheric Administration (NOAA),
Commerce.
ACTION: Notice; request for comments.
AGENCY:
The Assistant Regional
Administrator for Sustainable Fisheries,
Greater Atlantic Region, NMFS, has
made a preliminary determination that
an Exempted Fishing Permit application
contains all of the required information
and warrant further consideration. The
Exempted Fishing Permit would allow
commercial fishing vessels to land
Atlantic halibut under the minimum
size limit and in excess of the
possession limit. This EFP is required to
support an Atlantic halibut study by the
University of Massachusetts, Dartmouth,
School for Marine Science and
Technology, and The Nature
Conservancy to improve future halibut
stock assessments.
Regulations under the MagnusonStevens Fishery Conservation and
Management Act require publication of
this notification to provide interested
parties the opportunity to comment on
applications for proposed Exempted
Fishing Permits.
DATES: Comments must be received on
or before April 27, 2018.
ADDRESSES: You may submit written
comments by any of the following
methods:
• Email: NMFS.GAR.EFP@noaa.gov.
Include in the subject line ‘‘Comments
on TNC Atlantic halibut EFP.’’
• Mail: Michael Pentony, Regional
Administrator, NMFS, Northeast
Regional Office, 55 Great Republic
Drive, Gloucester, MA 01930. Mark the
outside of the envelope ‘‘TNC Atlantic
Halibut EFP.’’
FOR FURTHER INFORMATION CONTACT:
Spencer Talmage, Fishery Management
Specialist, 978–281–9232,
Spencer.Talmage@noaa.gov.
SUMMARY:
PO 00000
Frm 00037
Fmt 4703
Sfmt 4703
The
Nature Conservancy (TNC) submitted a
complete application for an Exempted
Fishing Permit (EFP) on March 6, 2018,
which requests a renewal of an EFP
issued last year to collect biological
samples of halibut. The project is
funded through the Saltonstall-Kennedy
Grant Program, and seeks to address
identified information gaps in order to
improve future Atlantic halibut stock
assessments. Research focuses on
characteristics such as stock structure,
seasonal movements, behavior, and life
history. The renewal application
requests the same exemptions from the
regulations that were approved for the
2017 fishing year. The exemptions
include the Atlantic halibut possession
limit, as described in § 648.86(c), and
the Atlantic halibut minimum size limit,
as described in § 648.83(a)(1).
The EFP would authorize 21
commercial fishing vessels to collect
biological samples of halibut during
regular fishing operations. A maximum
of five halibut may be sampled per trip.
Participating vessels may land halibut
under the minimum size limit and/or
above the possession limit provided
these fish are transferred to participating
researchers for additional data
collection. The EFP issued for the 2017
fishing year allowed for a total sampling
size of 250 halibut sampled across the
entirety of the project. To date, TNC has
sampled 132 halibut. The renewed EFP
would increase the total sample size to
275. TNC requested this increase in
order to fully utilize SaltonstallKennedy Grant Program funding.
Sampling would include recording of
fish length and weight, as well as
removal of gonads, otoliths, and genetic
material.
The exemption from the minimum
size limit would allow researchers to
collect data from all sizes of halibut,
which is necessary to ensure that results
of the project are accurate and reflective
of the halibut population. The
exemption from the possession limit is
necessary to ensure that the researchers
are able to obtain sufficient biological
samples to conduct their research. No
halibut above the possession limit or
below the minimum size limit could be
landed for sale.
Fishing under the EFP would occur
during the 2018 fishing year, from May
1, 2018 through April 30, 2019.
Participating vessels would use multiple
gear types, including handline/jig,
longline, sink gillnet, and otter trawl.
Fishing would occur throughout both
the Gulf of Maine and the Georges Bank
Regulated Mesh Areas, primarily in
statistical areas 514, 521, 522, 525, and
526.
SUPPLEMENTARY INFORMATION:
E:\FR\FM\12APN1.SGM
12APN1
Agencies
[Federal Register Volume 83, Number 71 (Thursday, April 12, 2018)]
[Notices]
[Pages 15795-15820]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2018-07573]
-----------------------------------------------------------------------
DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
RIN 0648-XG059
Takes of Marine Mammals Incidental to Specified Activities;
Taking Marine Mammals Incidental to Demolition and Reuse of the
Original East Span of the San Francisco-Oakland Bay Bridge
AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and
Atmospheric Administration (NOAA), Commerce.
ACTION: Notice; proposed incidental harassment authorization; request
for comments.
-----------------------------------------------------------------------
SUMMARY: NMFS has received a request from the California Department of
Transportation (Caltrans) for authorization to take marine mammals
during the dismantling and reuse of the original East Span of the San
Francisco-Oakland Bay Bridge (SFOBB) in the San Francisco Bay (SFB).
Pursuant to the Marine Mammal Protection Act (MMPA), NMFS is requesting
comments on its proposal to issue an incidental harassment
authorization (IHA) to incidentally take marine mammals during the
specified activities. NMFS will consider public comments prior to
making any final decision on the issuance of the requested MMPA
authorizations and agency responses will be summarized in the final
notice of our decision.
DATES: Comments and information must be received no later than May 14,
2018.
ADDRESSES: Comments should be addressed to Jolie Harrison, Chief,
Permits and Conservation Division, Office of Protected Resources,
National Marine Fisheries Service. Physical comments should be sent to
1315 East-West Highway, Silver Spring, MD 20910 and electronic comments
should be sent to [email protected].
Instructions: NMFS is not responsible for comments sent by any
other method, to any other address or individual, or received after the
end of the comment period. Comments received electronically, including
all attachments, must not exceed a 25-megabyte file size. Attachments
to electronic comments will be accepted in Microsoft Word or Excel or
Adobe PDF file formats only. All comments received are a part of the
public record and will generally be posted online at https://www.fisheries.noaa.gov/node/23111 without change. All personal
identifying information (e.g., name, address) voluntarily submitted by
the commenter may be publicly accessible. Do not submit confidential
business information or otherwise sensitive or protected information.
FOR FURTHER INFORMATION CONTACT: Sara Young, Office of Protected
Resources, NMFS, (301) 427-8401. Electronic copies of the application
and supporting documents, as well as a list of the references cited in
this document, may be obtained online at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-construction-activities. In case of problems
accessing these documents, please call the contact listed above.
SUPPLEMENTARY INFORMATION:
Background
Sections 101(a)(5)(A) and (D) of the MMPA (16 U.S.C. 1361 et seq.)
direct the Secretary of Commerce (as delegated to NMFS) to allow, upon
request, the incidental, but not intentional, taking of small numbers
of marine mammals by U.S. citizens who engage in a specified activity
(other than commercial fishing) within a 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.
An authorization for incidental takings shall be granted if NMFS
finds that the taking will have a negligible impact on the species or
stock(s), will not have an unmitigable adverse impact on the
availability of the species or stock(s) for subsistence uses (where
relevant), and if the permissible methods of taking and requirements
pertaining to the mitigation, monitoring and reporting of such takings
are set forth.
NMFS has defined ``negligible impact'' in 50 CFR 216.103 as an
impact resulting from the specified activity that cannot be reasonably
expected to, and is not reasonably likely to, adversely affect the
species or stock through effects on annual rates of recruitment or
survival.
The MMPA states that the term ``take'' means to harass, hunt,
capture, kill or attempt to harass, hunt, capture, or kill any marine
mammal.
[[Page 15796]]
Except with respect to certain activities not pertinent here, the
MMPA defines ``harassment'' as any act of pursuit, torment, or
annoyance which (i) has the potential to injure a marine mammal or
marine mammal stock in the wild (Level A harassment); or (ii) has the
potential to disturb a marine mammal or marine mammal stock in the wild
by causing disruption of behavioral patterns, including, but not
limited to, migration, breathing, nursing, breeding, feeding, or
sheltering (Level B harassment).
National Environmental Policy Act
To comply with the National Environmental Policy Act of 1969 (NEPA;
42 U.S.C. 4321 et seq.) and NOAA Administrative Order (NAO) 216-6A,
NMFS must review our proposed action (i.e., the issuance of an
incidental harassment authorization) with respect to potential impacts
on the human environment.
This action is consistent with categories of activities identified
in Categorical Exclusion B4 (incidental harassment authorizations with
no anticipated serious injury or mortality) of the Companion Manual for
NOAA Administrative Order 216-6A, which do not individually or
cumulatively have the potential for significant impacts on the quality
of the human environment and for which we have not identified any
extraordinary circumstances that would preclude this categorical
exclusion. Accordingly, NMFS has preliminarily determined that the
issuance of the proposed IHA qualifies to be categorically excluded
from further NEPA review.
We will review all comments submitted in response to this notice
prior to concluding our NEPA process or making a final decision on the
IHA request.
Summary of Request
On January 9, 2018, NMFS received a request from Caltrans for an
IHA to take marine mammals incidental to the demolition and reuse of
the original East Span of the SFOBB in San Francisco Bay. Caltrans'
request is for take of seven species of marine mammals, by Level B
harassment. Neither Caltrans nor NMFS expects serious injury or
mortality to result from this activity and, therefore, an IHA is
appropriate.
NMFS previously issued several IHAs to Caltrans for similar work,
with the most recent IHA issued in 2017 (82 FR 35510). Caltrans
complied with all the requirements (e.g., mitigation, monitoring, and
reporting) of the previous IHAs and information regarding their
monitoring results may be found in the Effects of the Specified
Activity on Marine Mammals and their Habitat and Estimated Take
section. This proposed IHA would cover one year of a larger project for
which Caltrans obtained previous IHAs. The larger project involves
dismantling of many piers of many remaining structures from the
original east span of the bridge.
Description of Proposed Activity
Overview
Caltrans proposes to demolish and reuse portions of the original
East Span of the SFOBB by mechanical dismantling and by use of
controlled charges to implode two piers (Piers E19 and E20) into their
open cellular chambers below the mudline. Activities associated with
dismantling of the piers may potentially result in incidental take of
marine mammals due to the use of highly controlled charges to dismantle
the marine foundations of the piers. A public access point will
incorporate existing piers (E21, E22, and E23) but requires use of pile
driving to finalize the access structure. Pier E2 will also be retained
for public access improvements, but does not require any in-water work.
Several previous one-year IHAs have been issued to Caltrans for
pile driving/removal and construction of the new SFOBB East Span
beginning in 2003. NMFS has issued 11 IHAs to Caltrans for the SFOBB
Project. The first five IHAs (2003, 2005, 2007, 2009, and 2011)
addressed potential impacts associated with pile driving for the
construction of the new East Span of the SFOBB. IHAs issued in 2013,
2014 and July 2015 addressed activities associated with both
constructing the new East Span and dismantling the original East Span,
specifically addressing vibratory pile driving, vibratory pile
extraction/removal, attenuated impact pile driving, pile proof testing,
and mechanical dismantling of temporary and permanent marine
foundations. On September 9, 2015, NMFS issued an IHA to Caltrans for
incidental take associated with the demolition of Pier E3 of the
original SFOBB by highly controlled explosives (80 FR 57584; September
24, 2015). On September 30, 2016, NMFS issued an IHA authorizing the
incidental take of marine mammals associated with both pile driving/
removal and controlled implosion of Piers E4 and E5 (81 FR 67313). On
July 13, 2017, NMFS issued an IHA to Caltrans authorizing take of
marine mammals for additional dismantling the original East Span of the
SFOBB using mechanical means as well as 5to 6 implosion events to
dismantle 13 piers (Piers E6-E18). This year of work will include
removal of Piers E19 and E20.
Dates and Duration
Vibratory pile driving for construction of the Oakland Touchdown
pedestrian bridge (OTD) and OTD access trestle may begin in June 2018.
Impact pile-driving activities will be restricted from June 1 to
November 30, to avoid peak salmonid migration periods. Pier implosion
requiring IHA coverage is scheduled to begin in September 2018. Pier
implosion will be restricted from September 1 to November 30, to
minimize potential impacts on biological resources in the Bay.
Specific Geographic Region
The SFOBB project area is located in the central SFB or Bay,
between Yerba Buena Island (YBI) and the city of Oakland. The western
limit of the project area is the east portal of the YBI tunnel, located
in the city of San Francisco. The eastern limit of the project area is
located approximately 1,312 feet (400 meters) west of the Bay Bridge
toll plaza, where the new and former spans of the bridge connect with
land at the OTD in the city of Oakland. The approximate width of the
in-water work area is 350 meters (1,148 feet). This includes all in-
water areas under the original bridge and new bridge. All activities
proposed under this IHA application will be confined to this area.
However, other previous in-water project activities have taken place in
discrete areas near both YBI and Treasure Island outside these limits.
Detailed Description of Specific Activity
Construction activities associated with both dismantling and reuse
of marine foundations of the original east span bridge may result in
the incidental take of marine mammals. These activities include the use
of highly controlled charges to dismantle Piers E19 and E20, as well as
pile-driving activities associated with construction of a public access
facility that will incorporate reuse Piers E21, E22 and E23. Pier E2
will also be retained and incorporated into a public access facility.
However, public access improvements at Pier E2 will not require any in-
water work and would not result in incidental take of marine mammals;
therefore, are not discussed further.
Removal of Piers 19 and 20
The removal of Piers E19 and E20 will be performed in three phases.
The first phase will use mechanical dismantling to remove the above-
water portions of
[[Page 15797]]
the piers, which is not expected to result in take. The second phase
will use controlled blasting methods for removal of the in-water
portions of the piers. The third phase will include dredging of
imploded rubble to specified removal limits, which is also not expected
to result in take. Limits of removal will be determined at each
location and will result in removal to between 0.46 and 0.91 meter (1.5
and 3 feet) below the mudline.
Piers E19 and E20 are large cellular structures through the water
column, which are supported on concrete slabs and hundreds of driven
timber piles encased in a concrete seal. The timber piles and concrete
seal courses that are below approved removal limits will remain in
place. Rubble that mounds above the determined debris removal elevation
limits from the dismantling of these piers will be removed off-site for
disposal; as was done during the removal of Piers E6 to E18.
A Blast Attenuation System (BAS) similar to that used for previous
blast events will be used during all future controlled blasting events,
to minimize potential impacts on biological resources in the Bay. The
effectiveness of this minimization measure is supported by the findings
from the successful removal of Piers E3 to E18.
Each pier will be removed in the following three phases:
Pre-blasting activities, including removing the pier cap
and concrete pedestals, installing and testing the BAS;
installing charges, activating the BAS, and imploding the
pier; and
dredging of imploded rubble to specified removal limits.
Further detail on the above steps to remove the marine foundations
are provided. Phase 1: Dismantling the concrete pedestals and concrete
pier cap by mechanical means (including the use of torches and
excavators mounted with hoe rams, drills, and cutting tools), and
drilling vertical boreholes where the charges will be loaded for
controlled blasting. Phase 2: The charges then will be loaded into the
drilled boreholes. Controlled blasting removal will be accomplished
using hundreds of small charges, with delays between individual
charges. The controlled blast sequence for each pier will last
approximately 1 to 5 seconds. The controlled blast removals have been
designed to remove each pier to between 0.46 and 0.91 meter (1.5 and 3
feet) below the mudline. Phase 3: Dredging of imploded rubble to
specified removal limits.
Blast Attenuation System Testing, Installation, and Deployment
The BAS will be deployed around each pier being imploded and will
be the same system as that successfully used for the removal of Piers
E3 to E18. The BAS is a modular system of pipe manifold frames, placed
around each pier and fed by air compressors to create a curtain of air
bubbles. Each BAS frame is approximately 15.4 meters long by 1.8 meters
wide (50.5 feet long by 6 feet wide). The BAS to be used will be the
same design that was used at Piers E3 to E18 and will meet the same
specifications. The BAS will be activated before and during implosion.
As shown during the Pier E3 Demonstration Project and eight subsequent
pier blast events by the SFOBB Project, the BAS will attenuate noise
and pressure waves generated during each controlled blast, to minimize
potentially adverse effects on biological resources that may be nearby.
Before installing the BAS, Caltrans will move any existing debris
on the Bay floor that may interrupt or conflict with proper
installation of the BAS. Each BAS frame will be lowered to the bottom
of the Bay by a barge-mounted crane and will be positioned into place.
Divers will assist frame placement and will the connect air hoses to
the frames. Based on location around the pier, the BAS frame elements
will be situated from approximately 8 to 12 meters (25 to 40 feet) from
the outside edge of each pier. The frames will be situated to
contiguously surround each pier. Frame ends will overlap to ensure no
break in the BAS when operational. Each frame will be weighted to
negative buoyancy for activation. Compressors will provide enough
pressure to achieve a minimal air volume fraction of 3 to 4 percent,
consistent with the successful use of BAS systems in past controlled
blasting activities.
The complete BAS will be installed and tested during the weeks
leading up to the controlled blast. The BAS test parameters will
include checking operating levels, flow rate, and a visual check to
determine that the system is operating correctly. System performance is
anticipated to provide approximately 80 percent noise and pressure
attenuation, based on the results from the previous SFOBB Project blast
events using a similar system.
Test blasts may be conducted to ensure that the hydroacoustic
monitoring equipment will be functional and triggered properly before
the pier implosion event. The test blasts would be conducted within the
completely installed and operating BAS. A key requirement of pier
implosion will involve accurately capturing hydroacoustic information
from the controlled blast. To accomplish this, a smaller test charge
will be used to trigger recording instrumentation. Multiple test blasts
on the same day may be required to verify proper instrument operation
and calibrate the equipment for the implosion events. These same
instruments and others of the same type will use high-speed recording
devices to capture hydroacoustic data at both near-field and far-field
monitoring locations during the implosion.
Test blasts will be scheduled to occur within two weeks of the
scheduled implosion. Tests will use a charge weight of approximately 18
grains (0.0025 pound) or less and will be placed along one of the
longer faces of the pier. The results from test blasts that occurred
before the implosions of Pier E3 and E5 indicate that these test blasts
will have minimal impacts on fish and no impacts on marine mammals (see
Appendix A in application).
Piers E19 and E20 will be imploded during a single event. Before
pier removal via controlled blasting, Caltrans will load the bore holes
of the piers with controlled charges. Individual cartridge charges
using electronic blasting caps have been selected to provide greater
control and accuracy in determining the individual and total charge
weights. Use of individual cartridges will allow a refined blast plan
that efficiently breaks concrete while minimizing the amount of charges
needed.
Boreholes will vary in diameter and depth, and have been designed
to provide optimal efficiency in transferring the energy created by the
controlled charges to dismantle the piers. Individual charge weights
will vary from 7 to 11 kilograms (15 to 25 pounds), and the total
charge weight for the Pier E19 and E20 blast event will be
approximately 1,800 kilograms (4,000 pounds). The total number of
individual charges to be used per pier will be approximately 100.
Charges will be arranged in different levels (decks) and will be
separated in the boreholes by stemming. Stemming is the insertion of
inert materials (e.g., sand or gravel) to insulate and retain charges
in an enclosed space. Stemming allows more efficient transfer of energy
into the structural concrete for fracture, and further reduces the
release of potential energy into the surrounding water column. The
entire detonation sequence, consisting of approximately 200
detonations, will last approximately 1 to 5 seconds for each pier; with
a minimum delay time of 9 milliseconds
[[Page 15798]]
(msec) between detonations. There will be approximately half a second
delay between pier blasts to avoid overlap of pressure waves.
Piers E19 and E20 will be blasted in a single pier implosion event.
These piers will be removed by blasting down through the concrete
cellular structure but not through the concrete slab, seal, and timber
piles below. Remaining concrete seals and timber piles below the
mudline will not be removed.
Reuse of Piers E21 to E23
Piers E19 and E20 will be imploded during a single event. Before
pier removal via controlled blasting, Caltrans will load the bore holes
of the pier with controlled charges. Individual cartridge charges using
electronic blasting caps have been selected to provide greater control
and accuracy in determining the individual and total charge weights.
Use of individual cartridges will allow a refined blast plan that
efficiently breaks concrete while minimizing the amount of charges
needed.
Boreholes will vary in diameter and depth, and have been designed
to provide optimal efficiency in transferring the energy created by the
controlled charges to dismantle the piers. Individual charge weights
will vary from 7 to 11 kilograms (15 to 25 pounds), and the total
charge weight for the Pier E19 and E20 blast event will be
approximately 1,800 kilograms (4,000 pounds). The total number of
individual charges to be used per pier will be approximately 100.
Charges will be arranged in different levels (decks) and will be
separated in the boreholes by stemming. Stemming is the insertion of
inert materials (e.g., sand or gravel) to insulate and retain charges
in an enclosed space. Stemming allows more efficient transfer of energy
into the structural concrete for fracture, and further reduces the
release of potential energy into the surrounding water column. The
entire detonation sequence, consisting of approximately 200
detonations, will last approximately 1 to 5 seconds for each pier; with
a minimum delay time of 9 msec between detonations. There will be
approximately half a second delay between pier blasts to avoid overlap
of pressure waves.
Proposed mitigation, monitoring, and reporting measures are
described in detail later in this document (please see ``Proposed
Mitigation'' and ``Proposed Monitoring and Reporting'').
Description of Marine Mammals in the Area of Specified Activities
Sections 3 and 4 of the application summarize available information
regarding status and trends, distribution and habitat preferences, and
behavior and life history, of the potentially affected species.
Additional information regarding population trends and threats may be
found in NMFS's Stock Assessment Reports (SAR; www.nmfs.noaa.gov/pr/sars/) and more general information about these species (e.g., physical
and behavioral descriptions) may be found on NMFS's website
(www.nmfs.noaa.gov/pr/species/mammals/).
Table 1 lists all species with expected potential for occurrence in
San Francisco Bay and summarizes information related to the population
or stock, including regulatory status under the MMPA and ESA and
potential biological removal (PBR), where known. For taxonomy, we
follow Committee on Taxonomy (2016). PBR is defined by the MMPA as the
maximum number of animals, not including natural mortalities, that may
be removed from a marine mammal stock while allowing that stock to
reach or maintain its optimum sustainable population (as described in
NMFS's SARs). While no mortality is anticipated or authorized here, PBR
and annual serious injury and mortality from anthropogenic sources are
included here as gross indicators of the status of the species and
other threats.
Marine mammal abundance estimates presented in this document
represent the total number of individuals that make up a given stock or
the total number estimated within a particular study or survey area.
NMFS's stock abundance estimates for most species represent the total
estimate of individuals within the geographic area, if known, that
comprises that stock. For some species, this geographic area may extend
beyond U.S. waters. All managed stocks in this region are assessed in
NMFS's U.S. 2016 SARs (Carretta et al., 2017). All values presented in
Table 1 are the most recent available at the time of publication and
are available in the 2016 SARs (Carretta et al., 2017) (available
online at: www.nmfs.noaa.gov/pr/sars/draft.htm).
Table 1--Marine Mammal Species That May Occur in the Action Area
--------------------------------------------------------------------------------------------------------------------------------------------------------
ESA/ MMPA status; Stock abundance (CV,
Common name Scientific name Stock Strategic (Y/N) Nmin, most recent PBR Annual M/
\1\ abundance survey) \2\ SI \3\
--------------------------------------------------------------------------------------------------------------------------------------------------------
Order Cetartiodactyla--Cetacea--Superfamily Mysticeti (baleen whales)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Family Eschrichtiidae:
Gray whale...................... Eschrichtius robustus.. Eastern North Pacific.. -; N 20,990 (0.05, 20,125, 624 132
2011).
Family Balaenopteridae (rorquals):
Fin Whale....................... Balaenoptera physalus.. California/Oregon/ E; Y 9,029 (0.12, 8,127, 81 2
Washington. 2014).
Humpback Whale.................. Megaptera novaeangliae. California/Oregon/ E; Y 1,918 (.03, 1,876, 11 6.5
Washington. 2014).
Minke Whale..................... Balaenoptera California/Oregon/ -; N 636 (0.72, 369, 2014). 3.5 1.3
acutorostrata. Washington.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Superfamily Odontoceti (toothed whales, dolphins, and porpoises)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Family Physeteridae:
Sperm whale..................... Physeter macrocephalus. California/Oregon/ E; Y 2,106 (0.58, 1,332, 2.7 1.7
Washington. 2008).
Family Delphinidae:
Common Bottlenose Dolphin....... Tursiops truncatus..... California Coastal..... -; N 453 (0.06, 346, 2011). 2.7 2
Short-Beaked Common Dolphin..... Delphinus delphis...... California/Oregon...... -; N 969,861 (0.17, 8,393 40
839,325, 2014).
Family Phocoenidae (porpoises):
Harbor Porpoise................. Phocoena phocoena...... San Francisco-Russian -; N 9,886 (0.51, 6,625, 66 0
River. 2011).
--------------------------------------------------------------------------------------------------------------------------------------------------------
[[Page 15799]]
Order Carnivora--Superfamily Pinnipedia
--------------------------------------------------------------------------------------------------------------------------------------------------------
Family Otariidae (eared seals and
sea lions):
California Sea Lion............. Zalophus californianus. United States.......... -; N 296,750 (N/A, 153,337, 9,200 389
2011).
Northern Fur Seal............... Callorhinus ursinus.... California, Eastern -; N 14,050 (N/A, 7,524, 451 1.8
North Pacific. 2013).
Steller sea lion................ Eumetopias jubatus..... Eastern................ T; D 41,638 (N/A, 41,638, 2,498 108
2015).
Family Phocidae (earless seals):
Harbor seal..................... Phoca vitulina......... California............. -; N 30,968 (N/A, 27,348, 1,641 43
2012).
Northern Elephant Seal.......... Mirounga angustirostris California Breeding.... -; N 179,000 (N/A, 81,368, 542 3.2
2010).
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Endangered Species Act (ESA) status: Endangered (E), Threatened (T)/MMPA status: Depleted (D). A dash (-) indicates that the species is not listed
under the ESA or designated as depleted under the MMPA. Under the MMPA, a strategic stock is one for which the level of direct human-caused mortality
exceeds PBR or which is determined to be declining and likely to be listed under the ESA within the foreseeable future. Any species or stock listed
under the ESA is automatically designated under the MMPA as depleted and as a strategic stock.
\2\ NMFS marine mammal stock assessment reports online at: www.nmfs.noaa.gov/pr/sars/. CV is coefficient of variation; Nmin is the minimum estimate of
stock abundance. In some cases, CV is not applicable [explain if this is the case].
\3\ These values, found in NMFS's SARs, represent annual levels of human-caused mortality plus serious injury from all sources combined (e.g.,
commercial fisheries, ship strike). Annual M/SI often cannot be determined precisely and is in some cases presented as a minimum value or range. A CV
associated with estimated mortality due to commercial fisheries is presented in some cases.
Note: Italicized species are not expected to be taken or proposed for authorization.
All species that could potentially occur in the proposed survey
areas are included in Table 1. However, the temporal or spatial
occurrence of the species italicized in Table 1 is such that take is
not expected to occur, and they are not discussed further beyond the
explanation provided here. San Francisco Bay would be considered
extralimital and have not been sighted during marine mammal monitoring
conducted by Caltrans under past IHAs.
Harbor Seal
Harbor seals are found from Baja California to the eastern Aleutian
Islands of Alaska. The species primarily hauls out on remote mainland
and island beaches and reefs, and estuary areas. Harbor seal tends to
forage locally within 53 miles (85 kilometers) of haul out sites
(Harvey and Goley 2011). Harbor seal is the most common marine mammal
species observed in the Bay and also commonly is seen near the SFOBB
east span (Department 2013b, 2013c). Tagging studies have shown that
most seals tagged in the Bay remain in the Bay (Harvey and Goley 2011;
Manugian 2013). Foraging often occurs in the Bay, as noted by
observations of seals exhibiting foraging behavior (short dives less
than 5 minutes, moving back and forth in an area, and sometimes tearing
up prey at the surface).
The molt occurs from May through June. During both pupping and molt
seasons, the number of seals and the length of time hauled out per day
increases, with about 60.5 percent of the population hauled out during
this time versus less than 20 percent in fall (Yochem et al., 1987;
Huber et al., 2001; Harvey and Goley 2011). Mother-pup pairs spend more
time on shore; therefore, the percentage of seals on shore at haul out
sites increases during the pupping season (Stewart and Yochem 1994).
Peak numbers of harbor seals hauling out in central California occurs
during late May to early June, which coincides with the peak of their
molt. Seals haul out more often and spend more time on shore to molt.
Yochem et al. (1987) found that harbor seals at San Miguel Island only
hauled out 11 to 19 percent of the time in fall, from late October
through early December.
Harbor seal tends to forage at night and haul out during the day.
Harbor seal predominately hauls out from 10 a.m. to 7 p.m., with a peak
in the afternoon between 1 and 4 p.m. (Yochem et al., 1987; Stewart and
Yochem 1994; Grigg et al., 2002; London et al., 2012). Harbor seals in
the Bay typically haul out in groups ranging from a few individuals to
several hundred seals. One known haul out site is on the southern side
of YBI, approximately 1,600 meters (5,250 feet) from Pier E6 and
approximately 2,800 meters (9,190 feet) from Pier E18. The YBI haul out
site had a daily range of zero to 109 harbor seals hauled out during
September, October, and November, with the highest numbers hauled out
during afternoon low tides (Department 2004b). Pile driving for the
SFOBB was not audible to the monitors just above the haul out site, and
no response to pile driving was observed.
Tide level also can affect haul out behavior, by exposing and
submerging preferred haul out sites. Tides likely affect the maximum
number of seals hauled out, but time of day and the season have the
greatest influence on haul out behavior (Stewart and Yochem 1994;
Patterson and Acevedo-Guti[eacute]rrez 2008).
Harbor seals in the Bay are an isolated population, although about
40 percent may move a short distance out of the Bay to forage (Manugian
et al. 2017). The Bay harbor seals likely are accustomed to a noisy
environment because of construction, vessel traffic, the Bay Area Rapid
Transit (BART) Transbay Tube, and mechanical noise (i.e., machinery,
generators).
During 251 days of SFOBB monitoring from 2000 through 2016, 958
harbor seals were observed in the vicinity of the SFOBB east span.
Harbor seals made up 90 percent of the marine mammals observed during
monitoring for the SFOBB Project. In 2015 and 2016, the number of
harbor seals sighted in the project area increased (8 days of
monitoring and 95 sightings). Foraging near the project area was
common, particularly in the coves adjacent to the YBI United States
Coast Guard Station and in Clipper Cove between YBI and Treasure
Island. Foraging also occurred in a shallow trench area southeast of
YBI (Department 2013a, 2013b). These sites are more than 900 to 1,525
meters (3,000 to 5,000 feet) west of Pier E6. In 2015, juvenile harbor
seals began foraging around Piers E2W and E2E of the new SFOBB east
span, and in 2016, they extended east around Piers E3 to E5 of the new
SFOBB east span. Foraging can occur throughout the Bay, and prey
abundance and distribution affect where harbor seals will forage. Most
of the harbor seal sightings were
[[Page 15800]]
animals transiting the area, likely moving from haul out sites or from
foraging areas.
California Sea Lion
California sea lion breeds on the offshore islands of California
from May through July (Heath and Perrin 2008). During the non-breeding
season, adult and sub-adult males and juveniles migrate northward along
the coast, to central and northern California, Oregon, Washington, and
Vancouver Island (Jefferson et al., 1993). They return south the
following spring (Lowry and Forney 2005; Heath and Perrin 2008).
Females and some juveniles tend to remain closer to rookeries
(Antonelis et al., 1990; Melin et al., 2008).
California sea lions have been observed occupying docks near Pier
39 in San Francisco, about 3.2 miles (5.2 kilometers) from the project
area, since 1987. The highest number of sea lions recorded at Pier 39
was 1,701 individuals in November 2009 (De Rango, pers. comm., 2013).
Occurrence of sea lions here typically is lowest in June (breeding
season) and highest in August. Approximately 85 percent of the animals
that haul out at this site are males, and no pupping has been observed
here or at any other site in the Bay (Lander, pers. comm., 1999). Pier
39 is the only regularly used haul out site in the project vicinity,
but sea lions occasionally haul out on human-made structures, such as
bridge piers, jetties, or navigation buoys (Riedman 1990).
During monitoring for the SFOBB Project, 80 California sea lions
were observed from 2000 through 2016. The number of sea lions that were
sighted in the project area decreased in 2015 and 2016. Sea lions
appear mainly to be transiting through the project area rather than
feeding, although two exceptions have occurred. In 2004, several sea
lions were observed following a school of Pacific herring that moved
through the project area, and one sea lion was observed eating a large
fish in 2015.
Breeding and pupping occur from mid to late May until late July.
After the mating season, adult males migrate northward to feeding areas
as far away as the Gulf of Alaska (Lowry et al., 1992), and they remain
away until spring (March-May), when they migrate back to the breeding
colonies. Adult females remain near the rookeries throughout the year
and alternate between foraging and nursing their pups on shore until
the next pupping/breeding season.
Northern Elephant Seal
Northern elephant seal is common on California coastal mainland and
island sites, where the species pups, breeds, rests, and molts. The
largest rookeries are on San Nicolas and San Miguel islands in the
northern Channel Islands. Near the Bay, elephant seals breed, molt, and
haul out at A[ntilde]o Nuevo Island, the Farallon Islands, and Point
Reyes National Seashore.
Northern elephant seals haul out to give birth and breed from
December through March. Pups remain onshore or in adjacent shallow
water through May. Both sexes make two foraging migrations each year:
One after breeding and the second after molting (Stewart 1989; Stewart
and DeLong 1995). Adult females migrate to the central North Pacific to
forage, and males migrate to the Gulf of Alaska to forage (Robinson et
al. 2012). Pup mortality is high when they make the first trip to sea
in May, and this period correlates with the time of most strandings.
Pups of the year return in the late summer and fall, to haul out at
breeding rookery and small haul out sites, but occasionally they may
make brief stops in the Bay.
Generally, only juvenile elephant seals enter the Bay and do not
remain long. The most recent sighting near the project area was in
2012, on the beach at Clipper Cove on Treasure Island, when a healthy
yearling elephant seal hauled out for approximately 1 day.
Approximately 100 juvenile northern elephant seals strand in or near
the Bay each year, including individual strandings at YBI and Treasure
Island (less than 10 strandings per year).
Northern Fur Seal
Northern fur seal breeds on the offshore islands of California and
in the Bering Sea from May through July. Two stocks of Northern fur
seals may occur near the Bay, the California and Eastern Pacific
stocks. The California stock breeds, pups, and forages off the
California coast. The Eastern Pacific stock breeds and pups on islands
in the Bering Sea, but females and juveniles move south to California
waters to forage in the fall and winter months.
Both the California and Eastern Pacific stocks forage in the
offshore waters of California, but only sick, emaciated, or injured fur
seals enter the Bay. The Marine Mammal Center (TMMC) occasionally picks
up stranded fur seals around YBI and Treasure Island. The rare
occurrence of northern fur seal near the SFOBB east span makes it
unlikely that the species will be exposed to implosion activities.
Bottlenose Dolphin
This species is found within 0.6 mile (1 kilometer) of shore and
occurs from northern Baja California, Mexico to Bodega Bay, with the
range extending north over the last several decades related to El
Ni[ntilde]o events and increased ocean temperatures. As the range of
bottlenose dolphins extended north, dolphins began entering the Bay in
2010 (Szczepaniak 2013). Until 2016, most bottlenose dolphins in the
Bay were observed in the western Bay, from the Golden Gate Bridge to
Oyster Point and Redwood City, although one individual was observed
frequently near the former Alameda Air Station (Perlman 2017). In 2017,
two individuals have been observed regularly near Alameda (Keener,
pers. comm., 2017) and likely passed by the project area.
Harbor Porpoise
This species seldom is found in waters warmer than 62.6 degrees
Fahrenheit (17 degrees Celsius) (Read 1990) or south of Point
Conception, and occurs as far north as the Bering Sea (Barlow and Hanan
1995; Carretta et al., 2009; Carretta et al., 2012; Allen and Angliss
2013). The San Francisco-Russian River stock is found from Pescadero,
18 miles (30 kilometers) south of the Bay, to 99 miles (160 kilometers)
north of the Bay at Point Arena (Carretta et al., 2012). In most areas,
harbor porpoise occurs in small groups, consisting of just a few
individuals.
Harbor porpoises are seen frequently outside the Bay, and they
began to re-enter the Bay in 2008. Keener et al. (2012) reports
sightings of harbor porpoises from just inside the Bay, northeast to
Tiburon and south to the SFOBB west span. In 17 years of monitoring in
the project area, 24 harbor porpoises have been observed, and all
occurred between 2006 and 2015; including two in 2014, five in 2015 and
15 in 2017. In 2017, the number of harbor porpoises in the project area
increased significantly. However, the majority of harbor porpoise
observations made during monitoring for the SFOBB Project have been at
distances ranging from 2,438 to 3,048 meters (8,000 to 10,000 feet)
from the work area.
Gray Whale
The eastern North Pacific population of gray whales ranges from the
southern tip of Baja California, Mexico to the Chukchi and Beaufort
Seas (Jefferson et al., 1993). The gray whale makes a well-defined,
seasonal north-south migration. Most of the population summers in the
shallow waters of the northern Bering Sea, the Chukchi Sea, and the
western Beaufort Sea (Rice and Wolman 1971). However, some individuals
also summer along the Pacific coast, from Vancouver Island to central
California
[[Page 15801]]
(Rice and Wolman 1971; Darling 1984; Nerini 1984). In October and
November, gray whales begin to migrate south and follow the shoreline
to breeding grounds along the western coast of Baja California and the
southeastern Gulf of California (Braham 1984). Gray whales begin
heading north in late winter and early spring (Rice and Wolman 1971).
The average gray whale migrates 4,660 to 6,213 miles (7,500 to 10,000
kilometers), at a rate of 91 miles/day (147 kilometers/day) (Jones and
Swartz 2002). Gray whales generally calve and breed during the winter,
in lagoons in Baja California (Jones and Swartz 2002), although some
calves are born along the California coast during the migration south.
Marine Mammal Hearing
Hearing is the most important sensory modality for marine mammals
underwater, and exposure to anthropogenic sound can have deleterious
effects. To appropriately assess the potential effects of exposure to
sound, it is necessary to understand the frequency ranges marine
mammals are able to hear. Current data indicate that not all marine
mammal species have equal hearing capabilities (e.g., Richardson et
al., 1995; Wartzok and Ketten, 1999; Au and Hastings 2008). To reflect
this, Southall et al. (2007) recommended that marine mammals be divided
into functional hearing groups based on directly measured or estimated
hearing ranges on the basis of available behavioral response data,
audiograms derived using auditory evoked potential techniques,
anatomical modeling, and other data. Note that no direct measurements
of hearing ability have been successfully completed for mysticetes
(i.e., low-frequency cetaceans). Subsequently, NMFS (2016) described
generalized hearing ranges for these marine mammal hearing groups.
Generalized hearing ranges were chosen based on the approximately 65 dB
threshold from the normalized composite audiograms, with the exception
for lower limits for low-frequency cetaceans where the lower bound was
deemed to be biologically implausible and the lower bound from Southall
et al. (2007) retained. The functional groups and the associated
frequencies are indicated below (note that these frequency ranges
correspond to the range for the composite group, with the entire range
not necessarily reflecting the capabilities of every species within
that group):
Low-frequency cetaceans (mysticetes): Generalized hearing
is estimated to occur between approximately 7 hertz (Hz) and 35
kilohertz (kHz);
Mid-frequency cetaceans (larger toothed whales, beaked
whales, and most delphinids): Generalized hearing is estimated to occur
between approximately 150 Hz and 160 kHz;
High-frequency cetaceans (porpoises, river dolphins, and
members of the genera Kogia and Cephalorhynchus; including two members
of the genus Lagenorhynchus, on the basis of recent echolocation data
and genetic data): Generalized hearing is estimated to occur between
approximately 275 Hz and 160 kHz.
Pinnipeds in water; Phocidae (true seals): Generalized
hearing is estimated to occur between approximately 50 Hz to 86 kHz;
Pinnipeds in water; Otariidae (eared seals): Generalized
hearing is estimated to occur between 60 Hz and 39 kHz.
The pinniped functional hearing group was modified from Southall et
al. (2007) on the basis of data indicating that phocid species have
consistently demonstrated an extended frequency range of hearing
compared to otariids, especially in the higher frequency range
(Hemil[auml] et al., 2006; Kastelein et al., 2009; Reichmuth and Holt,
2013).
For more detail concerning these groups and associated frequency
ranges, please see NMFS (2016) for a review of available information.
seven marine mammal species (three cetacean and four pinniped (three
otariid and one phocid) species) have the reasonable potential to co-
occur with the proposed survey activities. Please refer to Table 1. Of
the cetacean species that may be present, one is classified as low-
frequency cetaceans (gray whale), one is classified as mid-frequency
cetaceans (bottlenose dolphin), and one is classified as high-frequency
cetaceans (harbor porpoise).
Potential Effects of Specified Activities on Marine Mammals and Their
Habitat
This section includes a summary and discussion of the ways that
components of the specified activity may impact marine mammals and
their habitat. The ``Estimated Take by Incidental Harassment'' section
later in this document includes a quantitative analysis of the number
of individuals that are expected to be taken by this activity. The
``Negligible Impact Analysis and Determination'' section considers the
content of this section, the ``Estimated Take by Incidental
Harassment'' section, and the ``Proposed Mitigation'' section, to draw
conclusions regarding the likely impacts of these activities on the
reproductive success or survivorship of individuals and how those
impacts on individuals are likely to impact marine mammal species or
stocks.
General Information on Potential Effects
Explosives are impulsive sounds, which are characterized by short
duration, abrupt onset, and rapid decay. The proposed Caltrans SFOBB
work using controlled charges (i.e., implosion events) could adversely
affect marine mammal species and stocks by exposing them to elevated
noise levels in the vicinity of the activity area. Based on the nature
of the other activities associated with the dismantling of Piers E6
through E18 of the original SFOBB East Span (mechanical dismantling)
and measured sound levels from those activities during past monitoring
associated with previous IHAs, NMFS does not expect activities other
than implosion events to contribute to underwater noise levels such
that take of marine mammals would potentially occur.
Exposure to high intensity sound for a sufficient duration may
result in behavioral reactions and auditory effects such as a noise-
induced threshold shift--an increase in the auditory threshold after
exposure to noise (Finneran et al., 2005). Factors that influence the
amount of threshold shift include the amplitude, duration, frequency
content, temporal pattern, and energy distribution of noise exposure.
The magnitude of hearing threshold shift normally decreases over time
following cessation of the noise exposure. The amount of threshold
shift just after exposure is the initial threshold shift. If the
threshold shift eventually returns to zero (i.e., the threshold returns
to the pre-exposure value), it is a temporary threshold shift (Southall
et al., 2007).
When animals exhibit reduced hearing sensitivity (i.e., sounds must
be louder for an animal to detect them) following exposure to an
intense sound or sound for long duration, it is referred to as a noise-
induced threshold shift (TS). An animal can experience temporary
threshold shift (TTS) or permanent threshold shift (PTS). TTS can last
from minutes or hours to days (i.e., there is complete recovery), can
occur in specific frequency ranges (i.e., an animal might only have a
temporary loss of hearing sensitivity between the frequencies of 1 and
10 kHz), and can be of varying amounts (for example, an animal's
hearing sensitivity might be reduced initially by only 6 decibel (dB)
or reduced by 30 dB). PTS is a permanent loss within a specific
frequency range.
[[Page 15802]]
For cetaceans, published TTS data are limited to the captive
bottlenose dolphin, beluga, harbor porpoise, and Yangtze finless
porpoise (Finneran et al., 2000, 2002, 2003, 2005, 2007, 2010a, 2010b;
Finneran and Schlundt, 2010; Lucke et al., 2009; Mooney et al., 2009a,
2009b; Popov et al., 2011a, 2011b; Kastelein et al., 2012a; Schlundt et
al., 2000; Nachtigall et al., 2003, 2004). For pinnipeds in water, data
are limited to measurements of TTS in harbor seals, an elephant seal,
and California sea lions (Kastak et al., 1999, 2005; Kastelein et al.,
2012b).
Marine mammal hearing plays a critical role in communication with
conspecifics, and interpretation of environmental cues for purposes
such as predator avoidance and prey capture. Depending on the degree
(elevation of threshold in dB), duration (i.e., recovery time), and
frequency range of TTS, and the context in which it is experienced, TTS
can have effects on marine mammals ranging from discountable to serious
(similar to those discussed in auditory masking, below). For example, a
marine mammal may be able to readily compensate for a brief, relatively
small amount of TTS in a non-critical frequency range that occurs
during a time where ambient noise is lower and there are not as many
competing sounds present. Alternatively, a larger amount and longer
duration of TTS sustained during time when communication is critical
for successful mother/calf interactions could have more serious
impacts. Also, depending on the degree and frequency range, the effects
of PTS on an animal could range in severity, although it is considered
generally more serious because it is a permanent condition. Of note,
reduced hearing sensitivity as a simple function of aging has been
observed in marine mammals, as well as humans and other taxa (Southall
et al., 2007), so one can infer that strategies exist for coping with
this condition to some degree, though likely not without cost.
In addition, chronic exposure to excessive, though not high-
intensity, noise could cause masking at particular frequencies for
marine mammals that utilize sound for vital biological functions (Clark
et al., 2009). Acoustic masking occurs when other noises, such as those
from human sources, interfere with animal detection of acoustic signals
such as communication calls, echolocation sounds, and environmental
sounds important to marine mammals. Therefore, under certain
circumstances, marine mammals whose acoustical sensors or environment
are being severely masked could also be impaired from maximizing their
performance fitness in survival and reproduction.
Masking occurs at the frequency band, which the animals utilize.
However, lower frequency man-made noises are more likely to affect
detection of communication calls and other potentially important
natural sounds such as surf and prey noise. It may also affect
communication signals when they occur near the noise band and thus
reduce the communication space of animals (e.g., Clark et al., 2009)
and cause increased stress levels (e.g., Foote et al., 2004; Holt et
al., 2009).
Unlike TS, masking, which can occur over large temporal and spatial
scales, can potentially affect the species at population, community, or
even ecosystem levels, as well as individual levels. Masking affects
both senders and receivers of the signals and could have long-term
chronic effects on marine mammal species and populations. Recent
science suggests that low frequency ambient sound levels have increased
by as much as 20 dB (more than 3 times in terms of sound pressure
level) in the world's ocean from pre-industrial periods, and most of
these increases are from distant shipping (Hildebrand 2009). For
Caltrans' proposed SFOBB construction activities, noises from
controlled blasting is not likely to contribute to the elevated ambient
noise levels in the project area in such a way as to increasing
potential for or severity of masking. Baseline ambient noise levels in
the Bay are very high due to ongoing shipping, construction and other
activities in the Bay, and the sound associated with the controlled
blasting activities would be very brief.
Finally, exposure of marine mammals to certain sounds could lead to
behavioral disturbance (Richardson et al., 1995), such as: Changing
durations of surfacing and dives, number of blows per surfacing, or
moving direction and/or speed; reduced/increased vocal activities;
changing/cessation of certain behavioral activities (such as
socializing or feeding); visible startle response or aggressive
behavior (such as tail/fluke slapping or jaw clapping); avoidance of
areas where noise sources are located; and/or flight responses (e.g.,
pinnipeds flushing into water from haul outs or rookeries).
The onset of behavioral disturbance from anthropogenic noise
depends on both external factors (characteristics of noise sources and
their paths) and the receiving animals (hearing, motivation,
experience, demography) and is also difficult to predict (Southall et
al., 2007). For impulse noises (such as the proposed controlled
implosions associated with the dismantling of the original SFOBB
spans), NMFS uses received levels of 165 dB SEL to predict the onset of
behavioral harassment for mid-frequency cetaceans and phocid pinnipeds
(bottlenose dolphins and harbor seals and northern elephant seals,
respectively); 135 dB SEL for high-frequency cetaceans (harbor
porpoises); and 183 dB SEL for otariid pinnipeds (California sea lions
and northern fur seals).
The biological significance of many of these behavioral
disturbances is difficult to predict, especially if the detected
disturbances appear minor. However, the consequences of behavioral
modification could be biologically significant if the change affects
growth, survival, and/or reproduction, which depends on the severity,
duration, and context of the effects.
Potential Effects From Controlled Pier Implosion
It is expected that an intense impulse from the proposed controlled
blasting of Piers E19 and E20 would have the potential to impact marine
mammals in the vicinity of the activity. The majority of impacts would
be startle behavioral responses and temporary behavioral modification
of marine mammals. However, a few individual animals could be exposed
to sound levels that would cause TTS.
The underwater explosion would send a shock wave and blast noise
through the water, release gaseous by-products, create an oscillating
bubble, and cause a plume of water to shoot up from the water surface.
The shock wave and blast noise are of most concern to marine animals.
The effects of an underwater explosion on a marine mammal depends on
many factors, including the size, type, and depth of both the animal
and the explosive charge; the depth of the water column; and the
standoff distance between the charge and the animal, as well as the
sound propagation properties of the environment. Potential impacts can
range from brief effects (such as behavioral disturbance), tactile
perception, physical discomfort, slight injury of the internal organs
and the auditory system, to death of the animal (Yelverton et al.,
1973; DoN, 2001). Non-lethal injury includes slight injury to internal
organs and the auditory system; however, delayed lethality can be a
result of individual or cumulative sublethal injuries (DoN, 2001).
Immediate lethal injury would be a result of massive combined trauma to
internal organs as a direct result of proximity to the point of
detonation (DoN 2001). Generally, the higher the
[[Page 15803]]
level of impulse and pressure level exposure, the more severe the
impact to an individual.
Injuries resulting from a shock wave take place at boundaries
between tissues of different density. Different velocities are imparted
to tissues of different densities, and this can lead to their physical
disruption. Blast effects are greatest at the gas-liquid interface
(Landsberg 2000). Gas-containing organs, particularly the lungs and
gastrointestinal (GI) tract, are especially susceptible (Goertner 1982;
Hill 1978; Yelverton et al., 1973). In addition, gas-containing organs
including the nasal sacs, larynx, pharynx, trachea, and lungs may be
damaged by compression/expansion caused by the oscillations of the
blast gas bubble. Intestinal walls can bruise or rupture, with
subsequent hemorrhage and escape of gut contents into the body cavity.
Less severe GI tract injuries include contusions, petechiae (small red
or purple spots caused by bleeding in the skin), and slight
hemorrhaging (Yelverton et al., 1973).
Because the ears are the most sensitive to pressure, they are the
organs most sensitive to injury (Ketten 2000). Sound-related damage
associated with blast noise can be theoretically distinct from injury
from the shock wave, particularly farther from the explosion. If an
animal is able to hear a noise, at some level it can damage its hearing
by causing decreased sensitivity (Ketten 1995). Sound-related trauma
can be lethal or sublethal. Lethal impacts are those that result in
immediate death or serious debilitation in or near an intense source
and are not, technically, pure acoustic trauma (Ketten 1995). Sublethal
impacts include hearing loss, which is caused by exposures to
perceptible sounds. Severe damage (from the shock wave) to the ears
includes tympanic membrane rupture, fracture of the ossicles, damage to
the cochlea, hemorrhage, and cerebrospinal fluid leakage into the
middle ear. Moderate injury implies partial hearing loss due to
tympanic membrane rupture and blood in the middle ear. Permanent
hearing loss also can occur when the hair cells are damaged by one very
loud event, as well as by prolonged exposure to a loud noise or chronic
exposure to noise. The level of impact from blasts depends on both an
animal's location and, at outer zones, on its sensitivity to the
residual noise (Ketten 1995).
The above discussion concerning underwater explosions only pertains
to open water detonations in a free field. Caltrans' demolition of
Piers E19 and E20 using controlled implosion uses a confined detonation
method, meaning that the charges would be placed within the structure.
Therefore, most energy from the explosive shock wave would be absorbed
through the destruction of the structure itself, and would not
propagate through the open water. Measurements and modeling from
confined underwater detonation for structure removal showed that energy
from shock waves and noise impulses were greatly reduced in the water
column compared to expected levels from open water detonations (Hempen
et al., 2007; Department 2016). Therefore, with monitoring and
mitigation measures discussed below, Caltrans' controlled implosions of
Piers E19 and E20 are not likely to have injury or mortality effects on
marine mammals in the project vicinity. Instead, NMFS considers that
Caltrans' proposed controlled implosions in the San Francisco Bay are
most likely to cause behavioral harassment and may cause TTS in a few
individual of marine mammals, as discussed below.
Changes in marine mammal behavior are expected to result from acute
stress, or startle, responses. This expectation is based on the idea
that some sort of physiological trigger must exist to change any
behavior that is already being performed, and this may occur due to
being startled by the implosion events. The exception to this
expectation is the case of behavioral changes due to auditory masking
(increasing call rates or volumes to counteract increased ambient
noise). Masking is not likely since the Caltrans' controlled implosion
would only consist of five to six short, sequential detonations that
last for approximately 3-4 seconds each.
The removal of the SFOBB East Span is not likely to negatively
affect the habitat of marine mammal populations because no permanent
loss of habitat will occur, and only a minor, temporary modification of
habitat will occur due to the addition of sound and activity associated
with the dismantling activities.
Project activities will not affect any pinniped haul out sites or
pupping sites. The YBI harbor seal haul out site is on the opposite
site of the island from the SFOBB Project area. Because of the distance
and the island blocking the sound, underwater noise and pressure levels
from the SFOBB Project will not reach the haul out site. Other haul out
sites for sea lions and harbor seals are at a sufficient distance from
the SFOBB Project area that they will not be affected. The closest
recognized harbor seal pupping site is at Castro Rocks, approximately
8.7 miles (14 kilometers) from the SFOBB Project area. No sea lion
rookeries are found in the Bay.
The addition of underwater sound from SFOBB Project activities to
background noise levels can constitute a potential cumulative impact on
marine mammals. However, these potential cumulative noise impacts will
be short in duration and would not occur in biologically important
areas, would not significantly affect biologically important
activities, and are not expected to have significant environmental
effects, as noted in the original FHWA 2001 FEIS for the SFOBB project,
incorporated by reference into NMFS' 2003 EA and subsequent
Supplemental EAs (2009 and 2015) for the issuance of IHAs for the SFOBB
project.
Marine mammal forage on fish within SFB and pier implosions have
the potential to injure or kill fish in the immediate area. During
previous pier implosion and pile driving activities, Caltrans reported
mortality to prey species of marine mammals, including northern
anchovies and Pacific herring (Department 2016), averaging
approximately 200 fish per implosion event (none of which were ESA-
listed species and none of which are managed under a Fishery Management
Plan). These few isolated fish mortality events are not anticipated to
have a substantial effect on prey species populations or their
availability as a food resource for marine mammals.
Studies on explosives also suggest that larger fish are generally
less susceptible to death or injury than small fish, and results of
most studies are dependent upon specific biological, environmental,
explosive, and data recording factors. For example, elongated forms
that are round in cross section are less at risk than deep-bodied
forms; orientation of fish relative to the shock wave may also affect
the extent of injury; and finally, open water pelagic fish, such as
those expected to be in the project area, seem to be less affected than
reef fishes.
The huge variation in fish populations, including numbers, species,
sizes, and orientation and range from the detonation point, makes it
very difficult to accurately predict mortalities at any specific site
of detonation. Most fish species experience a large number of natural
mortalities, especially during early life-stages, and any small level
of mortality caused by the Caltrans' controlled implosion events will
likely be insignificant to the population as a whole. This negligible
effect on population levels of forage fish should ensure continued prey
availability for marine mammal species in the area.
[[Page 15804]]
Estimated Take
This section provides an estimate of the number of incidental takes
proposed for authorization through this IHA, which will inform both
NMFS' consideration of ``small numbers'' and the negligible impact
determination.
Harassment is the only type of take expected to result from these
activities. Except with respect to certain activities not pertinent
here, section 3(18) of the MMPA defines ``harassment'' as any act of
pursuit, torment, or annoyance which (i) has the potential to injure a
marine mammal or marine mammal stock in the wild (Level A harassment);
or (ii) has the potential to disturb a marine mammal or marine mammal
stock in the wild by causing disruption of behavioral patterns,
including, but not limited to, migration, breathing, nursing, breeding,
feeding, or sheltering (Level B harassment).
Authorized takes would be by Level B harassment only, in the form
of disruption of behavioral patterns and TTS, for individual marine
mammals resulting from exposure to pile driving and controlled
blasting. Based on the nature of the activity and the anticipated
effectiveness of the mitigation measures such as the use of a blast
attenuation system and shutdown zones, Level A harassment is neither
anticipated nor proposed to be authorized.
As described previously, no mortality is anticipated or proposed to
be authorized for this activity. Below we describe how the take is
estimated.
Described in the most basic way, we estimate take by considering:
(1) Acoustic thresholds above which NMFS believes the best available
science indicates marine mammals will be behaviorally harassed or incur
some degree of permanent hearing impairment; (2) the area or volume of
water that will be ensonified above these levels in a day; (3) the
density or occurrence of marine mammals within these ensonified areas;
and, (4) and the number of days of activities. Below, we describe these
components in more detail and present the proposed take estimate.
Acoustic Thresholds
Using the best available science, NMFS has developed acoustic
thresholds that identify the received level of underwater sound above
which exposed marine mammals would be reasonably expected to be
behaviorally harassed (equated to Level B harassment) or to incur PTS
of some degree (equated to Level A harassment). Thresholds have also
been developed to identify the pressure levels above which animals may
incur different types of tissue damage from exposure to pressure waves
from explosive detonation.
Level B Harassment for non-explosive sources--Though significantly
driven by received level, the onset of behavioral disturbance from
anthropogenic noise exposure is also informed to varying degrees by
other factors related to the source (e.g., frequency, predictability,
duty cycle), the environment (e.g., bathymetry), and the receiving
animals (hearing, motivation, experience, demography, behavioral
context) and can be difficult to predict (Southall et al., 2007,
Ellison et al., 2011). Based on what the available science indicates
and the practical need to use a threshold based on a factor that is
both predictable and measurable for most activities, NMFS uses a
generalized acoustic threshold based on received level to estimate the
onset of behavioral harassment. NMFS predicts that marine mammals are
likely to be behaviorally harassed in a manner we consider Level B
harassment when exposed to underwater anthropogenic noise above
received levels of 120 dB re 1 [mu]Pa (rms) for continuous (e.g.
vibratory pile-driving, drilling) and above 160 dB re 1 [mu]Pa (rms)
for non-explosive impulsive (e.g., seismic airguns) or intermittent
(e.g., scientific sonar) sources.
Caltrans's proposed activity includes the use of continuous
(vibratory pile driving) and impulsive (impact pile driving) sources,
and therefore the 120 and 160 dB re 1 [mu]Pa (rms) thresholds are
applicable.
Level A harassment for non-explosive sources--NMFS' Technical
Guidance for Assessing the Effects of Anthropogenic Sound on Marine
Mammal Hearing (Technical Guidance, 2016) identifies dual criteria to
assess auditory injury (Level A harassment) to five different marine
mammal groups (based on hearing sensitivity) as a result of exposure to
noise from two different types of sources (impulsive or non-impulsive).
Caltrans' proposed activity includes the use of impulsive (impact
driving) AND non-impulsive (vibratory driving) sources.
These thresholds are provided in the table below. The references,
analysis, and methodology used in the development of the thresholds are
described in NMFS 2016 Technical Guidance, which may be accessed at:
https://www.nmfs.noaa.gov/pr/acoustics/guidelines.htm.
Explosive sources--Based on the best available science, NMFS uses
the acoustic and pressure thresholds indicated in Table 2 to predict
the onset of behavioral harassment, PTS, tissue damage, and mortality.
Based on the best available scientific data, NMFS' 2016 Technical
Guidance for Assessing the Effects of Anthropogenic Sound on Marine
Mammal Hearing includes acoustic thresholds related to PTS and TTS for
impulsive sounds that are expressed as weighted, cumulative sound
exposure levels (SELcum) and unweighted peak sound pressure levels
(SPLPK), as presented in Table 3.
Table 2--NMFS Take Thresholds for Marine Mammals From Underwater Implosions
--------------------------------------------------------------------------------------------------------------------------------------------------------
Level B harassment Level A Serious injury
----------------------------------- harassment -----------------------------------
Group Species ------------------ Gastro- Mortality
Behavioral TTS intestinal Lung
PTS tract
--------------------------------------------------------------------------------------------------------------------------------------------------------
Mid-freq cetacean............ Bottlenose 165 dB SEL..... 170 dB SEL or 185 dB SEL or 237 dB SPL..... 39.1M 1/3 (1 + 91.4M 1/3 (1 +
dolphin. ............... 224 dB SPLpk. 230 dB SPLpk. ............... [D/10.081]) 1/2 [D/10.081]) 1/
High-freq cetacean........... ................ 135 dB SEL..... 140 dB SEL or 155 dB SEL or Pa-sec. 2 Pa-sec
Harbor porpoise. ............... 196 dB SPLpk. 202 dB SPLpk. where: M = mass where: M = mass
Phocidae..................... ................ 165 dB SEL..... 170 dB SEL or 185 dB SEL or of the animals of the animals
Harbor seal & ............... 212 dB SPLpk. 218 dB SPLpk. in kg. in kg
northern ............... ................ ................ D = depth of D = depth of
elephant seal. animal in m. animal in m.
Otariidae.................... California sea 183 dB SEL..... 188 dB SEL or 203 dB SEL or
lion & northern 226 dBpk. 232 dB SPLpk.
fur seal.
--------------------------------------------------------------------------------------------------------------------------------------------------------
* Note: All dB values are referenced to 1 [micro]Pa. SPLpk = Peak sound pressure level; psi = pounds per square inch.
[[Page 15805]]
[GRAPHIC] [TIFF OMITTED] TN12AP18.003
[[Page 15806]]
[GRAPHIC] [TIFF OMITTED] TN12AP18.004
Ensonified Area
Here, we describe operational and environmental parameters of the
activity that will feed into identifying the area ensonified above the
acoustic thresholds.
For pile removal activities, hydroacoustic monitoring was performed
during the implosions of Piers E3 through E18. Results for this
monitoring were used to determine distances to marine mammal threshold
criteria for underwater blasting. The criterion for lung injury and
mortality to marine mammals is dependent on the mass of the animal and
the depth of the animal in the water column; animals smaller in mass
are more susceptible to injury from impulse pressures. The criterion is
an impulse metric, expressed in pascal-second or psi-msec (Table 5).
The estimated mass of a juvenile fur seal (15 kilograms (33 pounds)),
was used in the lung injury and mortality calculations, because this
will be the smallest animal potentially to be exposed to the
implosions. The depth at which the animal is exposed also affects the
criterion threshold calculation. The water depth around Piers E19 and
E20 is very shallow, at 3 to 4 meters (10 to 12 feet). Although
implosions will take place in shallow areas, marine mammals are more
likely to be present in slightly deeper waters. Therefore, an average
depth for the project area of 6 meters (20 feet) was used in the
threshold calculation.
Caltrans proposes to use hydroacoustic monitoring results from the
implosions of Piers E3 through E18 to estimate distances to marine
mammal thresholds for the implosion of Piers E19 and E20 (Department
2015a, 2016). Measured distances from the implosion of Piers E17 to E18
(two-pier implosion event) were used to estimate distances to threshold
criteria for the implosion of Piers E19 and E20. The measured distances
to threshold criteria from the previous Pier E17 and E18 implosion
event are shown in Tables 5 and 6. Depictions of the isopleths for all
functional hearing groups is found in Figures 9-13 in the application.
[[Page 15807]]
Table 5--Measured Distances to Underwater Blasting Threshold Criteria for Level B Behavioral and TTS and Level A PTS From the Previous Implosion of
Piers E17 and E18 in a Single Event and Estimated Distances to These Threshold Criteria for the Proposed Implosion of Piers E19 and E20 in a Single
Event
--------------------------------------------------------------------------------------------------------------------------------------------------------
Behavioral TTS \1\ PTS \1\
Species hearing group -----------------------------------------------------------------------------------------------------------------------
Threshold 165 dB SELcum 224 dB Peak 170 dB SELcum 230 dB Peak 185 dB SELcum
--------------------------------------------------------------------------------------------------------------------------------------------------------
Mid-Frequency Cetaceans Piers E17-E18 511 feet.......... 40.84 meters...... 109.42 meters..... 27.13 meters...... 37.8 meters.
(Dolphins). Measured.
Piers E19-E20 200 meters........ 50 meters......... 120 meters........ 30 meters......... 40 meters.
Estimate.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Threshold 135 dB SELcum 196 dB Peak 140 dB SELcum 202 dB Peak 155 dB SELcum
--------------------------------------------------------------------------------------------------------------------------------------------------------
High-Frequency Cetaceans Piers E17-E18 1142.1 meters..... 279.2 meters...... 802.54 meters..... 185.01 meters..... 278.28 meters.
(Porpoises). Measured.
Piers E19-E20 1,220 meters...... 290 meters........ 830 meters........ 200 meters........ 290 meters.
Estimate.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Threshold 165 dB SELcum 212 dB Peak 170 dB SELcum 218 dB Peak 185 dB SELcum
--------------------------------------------------------------------------------------------------------------------------------------------------------
Phocid Pinnipeds (Seals)........ Piers E17-E18 278.59 meters..... 92.96 meters...... 195.38 meters..... 61.57 meters...... 67.36 meters.
Measured.
Piers E19-E20 290 meters........ 100 meters........ 200 meters........ 70 meters......... 70 meters.
Estimate.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Threshold 183 dB SELcum 226 dB Peak 188 dB SELcum 232 dB Peak 203 dB SELcum.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Otariid Pinnipeds (Sea Lions)... Piers E17-E18 75.9 meters....... 35.66 meters...... 53.04 meters...... 23.47 meters...... 18.29 meters.
Measured.
Piers E19-E20 80 meters......... 40 meters......... 60 meters......... 30 meters......... 20 meters.
Estimate.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Notes:
\1\ For the TTS and PTS criteria thresholds with dual criteria, the largest criteria distances (i.e., more conservative) are shown in bold.
Threshold Source: NMFS 2016.
Isopleth Distance Sources: Estimated distances to threshold criteria for the implosion of two small piers were determined based on measured distance to
threshold criteria from the implosion of Piers E17 and E18.
Table 6--Estimated Distances to Underwater Blasting Threshold Criteria for Level A GI Tract and Lung Injury and Mortality for Implosion of Pier E3, Two
Small Piers and Four Small Piers
--------------------------------------------------------------------------------------------------------------------------------------------------------
GI tract Lung \1\ Mortality \1\
--------------------------------------------------------------------------------------------------------------------------------
39.1 (15 kg)1/3 (1 91.4 (15 kg)1/3
Species + [6/10.081]) 1/2 (1 + [6/10.081])
Threshold 237 dB Peak 104 psi = 122 Pa-sec 1/2 = 285 Pa-sec
--------------------------------------------------------------------------------------------------------------------------------------------------------
All Species............ Piers E17-E18 55 feet.......................... 55 feet.......................... <40 feet.......... <40 feet.
Measured.
Pier Implosion 27 meters (89 feet).............. 27 meters (89 feet).............. <12 meters (<40 <12 meters (<40
Estimate. feet). feet).
--------------------------------------------------------------------------------------------------------------------------------------------------------
Notes:
Lung injury and mortality threshold calculations are for a 15-kilogram (33-pound) juvenile fur seal, the smallest marine mammal with the potential to be
present in the project area.
Threshold Source: Finneran and Jenkins 2012.
Isopleth Distance Sources: Estimated distances to threshold criteria for the implosion of piers were determined based on measured distance to threshold
criteria from the implosions of Pier E4, Piers E17 to E18, Piers E11 to E13 and Piers E14 to E16.
For pile driving, the distance to the marine mammal threshold
criteria for vibratory and impact driving were calculated based on
hydroacoustic measurements collected during previous pile-driving
activities for the SFOBB Project and other projects, involving similar
activities under similar conditions. Measured sound pressure levels
from other projects came from Caltrans' Compendium of Pile Driving
Sound Data (Department 2007), which provides information on sound
pressures resulting from pile driving measured throughout Northern
California. Distances to marine mammal threshold criteria were
calculated for all pile types and installation methods listed above.
These distances were calculated using the NMFS-provided companion User
Spreadsheet.
Table 7--NMFS User Spreadsheet Input Values for Pile Driving
----------------------------------------------------------------------------------------------------------------
24 inch steel 36 inch steel
Vibratory driving of steel piles H-Pile (vibratory) (vibratory) (vibratory)
----------------------------------------------------------------------------------------------------------------
Spreadsheet Tab Used................. (A) Non-Impulsive, Cont (A) Non-Impulsive, Cont (A) Non-Impulsive,
Cont.
Source Level (RMS SPL)............... 150.................... 165.................... 170.
[[Page 15808]]
Weighting Factor Adjustment (kHz).... 2.5.................... 2.5.................... 2.5.
a) Activity Duration (h) within 24-h 0.5.................... 1...................... 1.333333.
period.
Propagation (xLogR).................. 15..................... 15..................... 15.
Distance of source level (meters) *.. 10..................... 10..................... 10.
Other factors.
----------------------------------------------------------------------------------------------------------------
Impact driving of steel piles H-Pile (impact) 24 inch steel (impact) 36 inch steel (impact)
----------------------------------------------------------------------------------------------------------------
Spreadsheet Tab Used................. (E.1) Impact pile (E.1) Impact pile (E.1) Impact pile
driving. driving. driving.
Source Level (Single Strike/shot SEL) 160.................... 167 *.................. 170. *
Weighting Factor Adjustment (kHz).... 2...................... 2...................... 2.
a) Number of strikes in 1 h.......... 200.................... 450.................... 600.
a) Activity Duration (h) within 24-h 6...................... 4...................... 4.
period.
Propagation (xLogR).................. 15..................... 15..................... 15.
Distance of source level (meters) *.. 10..................... 10..................... 10.
Other factors........................ ....................... Using Bubble Curtain *. Using Bubble Curtain.*
----------------------------------------------------------------------------------------------------------------
Pile proofing (impact) H-Pile (impact) 24 inch steel (impact) 36 inch steel (impact)
----------------------------------------------------------------------------------------------------------------
Spreadsheet Tab Used................. (E.1) Impact pile (E.1) Impact pile (E.1) Impact pile
driving. driving. driving.
Source Level (Single Strike/shot SEL) 160.................... 177.................... 180.
Weighting Factor Adjustment (kHz).... 2...................... 2...................... 2.
a) Number of strikes in 1 h.......... 20..................... 20..................... 20.
a) Activity Duration (h) within 24-h 2...................... 2...................... 2.
period.
Propagation (xLogR).................. 15..................... 15..................... 15.
Distance of source level (meters) *.. 10..................... 10..................... 10.
Other factors.
----------------------------------------------------------------------------------------------------------------
Impact driving of concrete piles 24 inch concrete (impact) 36 inch concrete (impact)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Spreadsheet Tab Used............... (E.1) Impact pile driving.................................................. (E.1) Impact pile driving.
Source Level (Single Strike/shot 160........................................................................ 160.*
SEL).
Weighting Factor Adjustment (kHz).. 2.......................................................................... 2.
a) Number of strikes in 1 h........ 1200....................................................................... 1400.
a) Activity Duration (h) within 24- 5.......................................................................... 5.
h period.
Propagation (xLogR)................ 15......................................................................... 15.
Distance of source level (meters) * 10......................................................................... 10.
Other factors...................... ........................................................................... Using Bubble Curtain.*
--------------------------------------------------------------------------------------------------------------------------------------------------------
* Attenuated value--Bubble curtain is assumed to provide 10dB of attenuation.
For calculation of SELcum threshold distances, the following
assumptions were made:
Only one type/size of pile will be installed on the same
day;
Only one pile installation method, impact or vibratory,
will be performed on the same day;
A maximum of four steel pipe piles will be installed
(impact driving or vibratory) on the same day;
A maximum of six H-piles will be installed (impact or
vibratory) on the same day; and
A maximum of two pile will be proof-tested with an impact
hammer on the same day; administering a maximum of 20 strikes per pile.
The distances to the marine mammal threshold criteria for these
pile driving and pile removal activities are shown in Table 8.
Table 8--Distances to Levels A and B Harassment Threshold Criteria for Impact and Vibratory Pile Driving and Pile Removal
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Parameters Level B ZOI radii (meters) Level A ZOI radii (meters)
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Low- Mid- High-
Pile size and type Drive method Piles per Attenuation system 160 dB 120 dB RMS frequency frequency frequency Phocid Otariid
day RMS cetaceans cetaceans cetaceans pinnipeds pinnipeds
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
H-Pile............................... Vibratory............... 6 None.................... NA 1,000................... 1 1 2 1 1
24 inch steel........................ Vibratory............... 4 None.................... NA Calculated.............. 13 1 19 8 1
Practical 2,000.........
36 inch steel........................ Vibratory............... 4 None.................... NA Calculated.............. 33 3 49 20 1
Practical 2,000.........
H-Pile............................... Impact.................. 6 None.................... 100 NA...................... 33 1 39 18 1
24 inch steel........................ Impact.................. 4 Bubble Curtain.......... 215 NA...................... 127 5 151 68 5
36 inch steel........................ Impact.................. 4 Bubble Curtain.......... 541 NA...................... 243 9 290 130 9
24 inch concrete..................... Impact.................. 5 None.................... 46 NA...................... 97 3 115 52 4
36 inch concrete..................... Impact.................. 5 Bubble Curtain.......... 117 NA...................... 107 4 127 57 4
H-Pile............................... Proof Testing........... 2 None.................... 100 NA...................... 3 0 4 2 0
24 inch steel........................ Proof Testing........... 2 None.................... 1,000 NA...................... 46 2 55 25 2
[[Page 15809]]
36 inch steel........................ Proof Testing........... 2 None.................... 2,512 NA...................... 74 3 88 39 3
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Sources: Sound levels from the Department's Compendium of Pile Driving Sound Data (Department 2007). Distances were calculated using the NMFS-provided companion User Spreadsheet, available at
https://www.nmfs.noaa.gov/pr/acoustics/guidelines.htm.
The distance to the 120 dB rms Level B Zone of Influence (ZOI)
threshold for vibratory pile driving was calculated to be 10,000 meters
for 24-inch (0.61-meter) diameter steel pipe piles and 21,544 meters
for 36-inch (0.91-meter) diameter steel pipe piles. Previous monitoring
for the SFOBB Project has shown background sound levels in the active
portions of the Bay, near the project area, to range from 110 to 140 dB
rms, with typical background levels in the range of 110 to 120 dB rms
(Department 2015). During previous hydroacoustic monitoring for the
SFOBB Project, it has not been possible to detect or distinguish sound
from vibratory pile driving beyond 1,000 to 2,000 meters (3,280 to
6,562 feet) from the source (Rodkin 2009). Under all previous IHAs for
the SFOBB Project, which included vibratory pile driving, the ZOI for
this activity has been set at 2,000 meters (6,562 feet) or less (NOAA
2016). Furthermore, it unlikely that marine mammals in the Bay will
detect or show response to this sound at distances greater than 2,000
meters (6,562 feet), because of the background sound levels in the
Central Bay. Therefore, the practical, applied ZOI for the vibratory
driving of 24-inch (0.61-meter) and 36-inch (0.91-meter) diameter steel
pipe piles has been set at 2,000 meters (6,562 feet), as shown in Table
7.
When NMFS Technical Guidance (2016) was published, in recognition
of the fact that ensonified area/volume could be more technically
challenging to predict because of the duration component in the new
thresholds, we developed a User Spreadsheet that includes tools to help
predict a simple isopleth that can be used in conjunction with marine
mammal density or occurrence to help predict takes. We note that
because of some of the assumptions included in the methods used for
these tools, we anticipate that isopleths produced are typically going
to be overestimates of some degree, which will result in some degree of
overestimate of Level A take. However, these tools offer the best way
to predict appropriate isopleths when more sophisticated 3D modeling
methods are not available, and NMFS continues to develop ways to
quantitatively refine these tools, and will qualitatively address the
output where appropriate. For stationary sources pile driving, NMFS
User Spreadsheet predicts the closest distance at which, if a marine
mammal remained at that distance the whole duration of the activity, it
would not incur PTS. Inputs used in the User Spreadsheet, and the
resulting isopleths are reported below in Table 8.
Marine Mammal Occurrence
In this section we provide the information about the presence,
density, or group dynamics of marine mammals that will inform the take
calculations.
No systematic line transect surveys of marine mammals have been
performed in the Bay. Therefore, the in-water densities of harbor
seals, California sea lions, and harbor porpoises were calculated based
on 17 years of observations during monitoring for the SFOBB
construction and demolition. Care was taken to eliminate multiple
observations of the same animal, although this can be difficult and is
likely that the same individual may have been counted multiple times on
the same day. The amount of monitoring performed per year varied,
depending on the frequency and duration of construction activities with
the potential to affect marine mammals. During the 257 days of
monitoring from 2000 through 2017 (including 15 days of baseline
monitoring in 2003), 1,029 harbor seals, 83 California sea lions, and
24 harbor porpoises were observed in waters in the project vicinity in
total. In 2015, 2016, and 2017, the number of harbor seals in the
project area increased significantly. In 2017, the number of harbor
porpoise in the project area also increased significantly. Therefore, a
harbor seal density estimate was calculated for 2015-2017, and a harbor
porpoise density estimate was calculated for 2017, which may better
reflect the current use of the project area by these animals. These
observations included data from baseline, pre-, during, and post-pile
driving, mechanical dismantling, on-shore blasting, and off-shore
implosion activities.
Insufficient sighting data exist to estimate the density of
bottlenose dolphins. However, a single bottlenose dolphin has been
observed regularly, south of the SFOBB east span since fall 2016.
During monitoring performed in 2017 for the SFOBB, two bottlenose
dolphins were observed south of the SFOBB.
Insufficient sighting data exist to estimate elephant seal
densities in the Bay. Generally, only juvenile elephant seals enter the
Bay and do not remain long. The most recent sighting near the project
area was in 2012, on the beach at Clipper Cove on Treasure Island, when
a healthy yearling elephant seal hauled out for approximately 1 day.
Approximately 100 juvenile northern elephant seals strand in or near
the Bay each year, including individual strandings at YBI and Treasure
Island (less than 10 strandings per year).
Insufficient sighting data exist to estimate northern fur seal
densities in the Bay. Only two to four northern fur seals strand in the
Bay each year, and they are unlikely to occur in the project area.
The size of the areas monitored for marine mammals has increased
over the 17 years of observations. The majority of pinniped monitoring
has been focused within a 610-meter (2,000-foot) radius of the work
area. Although some pinniped observations have been recorded at greater
distances, in part because of recent monitoring of larger areas for
harbor porpoise zones during pier implosion, a 2-square-kilometer area,
corresponding with a 610-meter (2,000-foot) radial distance, was used
for density calculations. Harbor porpoise sightings in the Bay have
increased in recent years; however, the majority of harbor porpoise
observations made during monitoring for the SFOBB Project have been at
distances ranging from 2,438 to 3,048 meters (8,000 to 10,000 feet)
from the work area. Therefore, harbor porpoise densities were
calculated based on a 15-square-kilometer area, corresponding with a
2,438-meter (8,000-foot) radial distance, with land areas subtracted
from the
[[Page 15810]]
area. Numbers used for density calculations are shown in Table 9. In
the cases where densities were refined to capture a narrower range of
years to be conservative, bold densities were used for take
calculations.
Table 9--Estimated In-water Density of Marine Mammal Species in SFOBB Area
----------------------------------------------------------------------------------------------------------------
Area of
monitoring Days of Number of Density animals/square
Species observed zone (square monitoring animals kilometer
kilometer) observed
----------------------------------------------------------------------------------------------------------------
Harbor seals, 2000-2017............... 2 257 1029 2.002.
Harbor Seals, 2015-2017............... 2 47 372 3.957.
California Sea Lions, 2000-2017....... 2 257 83 0.161.
Bottlenose Dolphins 2017.............. 2 6 2 Insufficient sighting
data exists to estimate
density.
Harbor Porpoise, 2000-2017............ 3 257 24 0.031.
Harbor Porpoise, 2017................. 15 6 15 0.167.
Elephant Seal, 2000-2017.............. 2 257 0 Insufficient sighting
data exists to estimate
density.
Northern Fur Seal, 2000-2017.......... 2 257 0 Insufficient sighting
data exists to estimate
density.
Gray Whale, 2000-2017................. 2 257 0 Insufficient sighting
data exists to estimate
density.
----------------------------------------------------------------------------------------------------------------
Notes:
Densities for Pacific harbor seals, California sea lions, and harbor porpoises are based on monitoring for the
east span of the SFOBB from 2000 to 2017.
A second set of Pacific harbor seal densities were calculated from the increase in sightings recorded from 2015
to 2017.
A second set of harbor porpoise densities were calculated for the increase in sightings that were recorded in
2017.
Bold densities were used for take calculations.
Sources: Department 2001, 2004b, 2013b, 2013c, 2014, 2015b, 2016, 2017; Perlman 2017.
For species without enough sightings to construct a density
estimate, Caltrans uses information based on group size and frequency
of sightings from previous years of work to inform the number of
animals estimated to be taken, which is detailed in the Take Estimation
section below.
Take Calculation and Estimation
Here we describe how the information provided above is brought
together to produce a quantitative take estimate.
Take From Pier Implosion
The numbers of harbor seals, sea lions and harbor porpoise that may
be taken by implosion of Piers E19 and E20 were calculated based on
distances to the marine mammal threshold criteria, duration of the
activity, and the estimated density of these species in the ZOI.
The numbers of elephant seals, northern fur seals and bottlenose
dolphin that may be taken by implosion of Piers E19 and E20 were
determined based on distances to the marine mammal threshold criteria,
duration of the activity, and sightings and occurrence of these species
in the Bay, specifically near the project area. Distances to marine
mammal threshold criteria were calculated based on the highest sound
pressure levels generated during the previous pier implosion of Piers
E17 and E18 (two-pier implosion event) . Gray whales were not
considered for pier implosion activities as those activities will occur
in late fall and early winter, when gray whales are not found in the
Bay area.
The number of exposures of each species was calculated over the
entire area of each Level A, Level B, and mortality threshold criteria
zone for the proposed pier implosion event (Tables 10 through 12).
Table 10--Level A PTS Take Calculations for Implosion of Piers E19 and E20
--------------------------------------------------------------------------------------------------------------------------------------------------------
Species
density Species Level A PTS Number of
Species (animals/ density Level A ZOI ZOI area Level A PTS implosion Level B take
square (animals/ radii (meters) (square take events calculated
kilometer) square meters) meters)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Harbor Seal............................. 3.957 3.96E-06 70 29462.347 0.1166 1 0.1166
Sea Lion................................ 0.161 1.61E-07 30 9118.458 0.0015 1 0.0015
Harbor Porpoise......................... 0.167 1.67E-07 290 315798.484 0.0527 1 0.0527
Bottlenose Dolphin...................... NA NA 40 5026.548 NA 1 NA
Elephant Seal........................... NA NA 70 15393.804 NA 1 NA
Fur Seal................................ NA NA 30 2827.43 NA 1 NA
--------------------------------------------------------------------------------------------------------------------------------------------------------
[[Page 15811]]
Table 11--Level B TTS Take Calculations for Implosion of Piers E19 and E20
--------------------------------------------------------------------------------------------------------------------------------------------------------
Species
density Species Level B TTS Number of pier
Species (animals/ density Level B ZOI ZOI area Level B TTS implosion Level B take
square (animals/ radii (meters) (square take events calculated
kilometer) square meters) meters)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Harbor Seal............................. 3.957 3.96E-06 200 164964.771 0.6528 1 0.6528
Sea Lion................................ 0.161 1.61E-07 60 23434.268 0.0038 1 0.0038
Harbor Porpoise......................... 0.167 1.67E-07 830 2085701.996 0.3483 1 0.3483
Bottlenose Dolphin...................... NA NA 120 45238.934 NA 1 NA
Elephant Seal........................... NA NA 200 125663.706 NA 1 NA
Fur Seal................................ NA NA 60 11309.73 NA 1 NA
--------------------------------------------------------------------------------------------------------------------------------------------------------
Table 12--Level B Behavioral Take Calculations for Implosion of Piers E19 and E20
--------------------------------------------------------------------------------------------------------------------------------------------------------
Species
density Species Level B Level B Number of pier
Species (animals/ density Level B ZOI behavioral ZOI behavioral implosion Level B take
square (animals/ radii (meters) area (square take events calculated
kilometer) square meters) meters)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Harbor Seal............................. 3.957 3.96E-06 290 315798.486 1.2496 1 1.2496
Sea Lion................................ 0.161 1.61E-07 80 36118.343 0.0058 1 0.0058
Harbor Porpoise......................... 0.167 1.67E-07 1,220 4256937.444 0.7109 1 0.7109
Bottlenose Dolphin...................... NA NA 200 125663.706 NA 1 NA
Elephant Seal........................... NA NA 290 264207.942 NA 1 NA
Fur Seal................................ NA NA 80 20106.19 NA 1 NA
--------------------------------------------------------------------------------------------------------------------------------------------------------
Table 13--Combined Estimated Exposures of Marine Mammals to the Pier Implosions for Levels A and B, and Mortality Threshold Criteria
--------------------------------------------------------------------------------------------------------------------------------------------------------
Level B exposures for all Level A exposures \1\
implosions ------------------------------------------------
--------------------------------
Species Temporary Permanent Gastro- Slight lung Mortality \1\
Behavioral threshold threshold intestinal injury
response shift shift tract injury
--------------------------------------------------------------------------------------------------------------------------------------------------------
Pacific Harbor Seal..................................... 1 1 0 0 0 0
California Sea Lion..................................... 0 0 0 0 0 0
Northern Elephant Seal.................................. 0 0 0 0 0 0
Northern Fur Seal....................................... 0 0 0 0 0 0
Bottlenose Dolphin...................................... 0 0 0 0 0 0
Harbor Porpoise......................................... 1 0 0 0 0 0
-----------------------------------------------------------------------------------------------
Total............................................... 2 1 0 0 0 0
--------------------------------------------------------------------------------------------------------------------------------------------------------
Note:
\1\ No implosion will occur if any marine mammal is within the Level A or mortality threshold criteria zones.
Based on the distances to the marine mammal threshold criteria and
estimated species density, it is not expected that GI tract, lung
injury, or mortality could occur from the pier implosion event.
Approximately two harbor seals (one by behavioral response and one by
TTS) and one harbor porpoise (by behavioral response) may be taken by
Level B harassment during the implosion Piers E19 and E20 (Table 12).
No take of any other species is anticipated.
The estimated number of marine mammals to be exposed to implosion
SPLs for each threshold criteria (Table 13) are based on current
density estimates or occurrence of marine mammals in the project area
(Table 9 through 12). However, the number of marine mammals in the area
at any given time is highly variable. Animal movement depends on time
of day, tide levels, weather, and availability and distribution of prey
species. Therefore, Caltrans requests the following number of allowable
harassment takes for each Level B harassment criteria threshold (Table
14).
Table 14--Amount of Level B Harassment Take Requested for the Implosions
of Piers E19 and E20
------------------------------------------------------------------------
Level B harassment take \1\
-------------------------------
Species Temporary
Behavioral threshold
response shift
------------------------------------------------------------------------
Pacific Harbor Seal..................... 20 10
California Sea Lion..................... 4 3
Northern Elephant Seal.................. 2 1
Northern Fur Seal....................... 2 1
Harbor Porpoise......................... 5 5
[[Page 15812]]
Bottlenose Dolphin...................... 4 2
-------------------------------
Total............................... 42 25
------------------------------------------------------------------------
Note:
\1\ Pier implosion will be delayed if any marine mammals are detected
within any of the Level A or mortality threshold criteria exclusion
zones.
Pacific Harbor Seal: As discussed above, harbor seal is the most
numerous marine mammal in the Bay. However, take calculated based on
species density and the distances to the marine mammal threshold
criteria indicated that only two harbor seals would be exposed to sound
pressure levels that can result in Level B harassment (Table 13). One
of those exposures would be within the Level B monitoring zone, and one
would be within the TTS zone (Table 13). Based on previous monitoring
the number of harbor seals in the water can vary greatly, depending on
weather conditions or the availability of prey. For example, during
Pacific herring runs further north in the Bay (near Richardson Bay) in
February 2014, very few harbor seals were observed foraging near YBI or
transiting through the project area for approximately 2 weeks.
Sightings went from a high of 27 harbor seal individuals foraging or in
transit in one day to no seals per day in transit or foraging through
the project area (Department 2014). In 2015 and 2016, the number of
harbor seal sighting in a single day in the project area increased up
to 41 seals (Department 2015b, 2016). Because of this high degree of
variability, and the observation of up to 41 seals in the project area
in a single day Caltrans are requesting authorization for the take of
30 harbor seals by Level B harassment (20 by Level B behavioral
response and 10 by Level B TTS) (Table 14).
California Sea Lion: As discussed above, California sea lion is the
second most numerous marine mammal species in the Bay, after the harbor
seal. However, take calculated based on species density and the
distances to the marine mammal threshold criteria indicated that no sea
lions would be exposed to sound pressure levels that can result in
Level B harassment (Table 13). Based on previous monitoring the number
of sea lions transiting through or foraging in the project area can
vary greatly. Because of the high degree of variability, regular
observation of sea lions in the project area, and because this species
may travel in groups Caltrans are requesting authorization for the take
of seven sea lions (four by Level B behavioral response and three by
Level B TTS) (Table 14).
Harbor Porpoises: Based on the calculated density estimates and the
distances to the marine mammal threshold criteria, one harbor porpoise
(by behavioral response) may be taken by Level B harassment during the
implosion of Piers E19 and E20 (Table 13). However the number of harbor
porpoise in the Bay and their foraging range appears to be steadily
increasing. This high-frequency cetacean has a large ZOI, because of
its sensitivity to anthropogenic sound. Further, this species generally
travels in either calf cow pairs or small pods of four to five
porpoises. For these reasons Caltrans are requesting authorization for
the take of 10 harbor porpoise (five by Level B behavioral response and
five by Level B TTS) (Table 14).
Northern Elephant Seal: As discussed above, because of the
infrequent observation of this species in the Bay, Caltrans estimates
that no elephant seals will be exposed to SPLs that can result in Level
B harassment (Table 13). However, the number of elephant seals that may
enter and or strand in the Bay in a given year is highly variable;
dependent on changes in oceanographic conditions, effecting water
temperature and prey availability. Caltrans wants to ensure that the
project has coverage for the incidental take of any species with the
potential to be present in the project area. Therefore, Caltrans are
requesting authorization for the take of three elephant seals (two by
Level B behavioral response and one by Level B TTS) (Table 14).
Northern Fur Seal: As discussed above, northern fur seals are found
infrequently in the Bay and are unlikely to be in the vicinity of the
pier implosion. However, the number of fur seals that may enter and or
strand in the Bay in a given year is highly variable; dependent on
changes in oceanographic conditions, effecting water temperature and
prey availability. Caltrans wants to ensure that the project has
coverage for the incidental take of any species with the potential to
be present in the project area. Therefore, they are requesting
authorization for the take of three northern fur seals (two by Level B
behavioral response and one by Level B TTS) (Table 14).
Bottlenose Dolphin: As discussed above, only small numbers of
bottlenose dolphin occur in the project vicinity. Based on the low
number of individuals in the Bay and the distances to the marine mammal
threshold criteria Caltrans anticipates that no bottlenose dolphins
would be exposed to SPLs that can result in Level B harassment.
However, as discussed in Chapter 4, until 2016, most bottlenose
dolphins in the Bay were observed in the western Bay, from the Golden
Gate Bridge to Oyster Point and Redwood City, although one individual
was observed frequently near the former Alameda Air Station (Perlman
2017). As of 2017, the same two individuals have been observed
regularly near Alameda (Keener, pers. comm., 2017) and likely pass by
the project area. If additional individuals begin using this eastern
area of the Bay, the number of bottlenose sightings near the project
area will likely increase. Caltrans wants to ensure that the project
has coverage for the incidental take of any species with the potential
to be present in the project area. Therefore, they are requesting
authorization for the take of six bottlenose dolphins (four by Level B
behavioral response and two by Level B TTS) (Table 14).
Take From Pile Driving
The numbers of marine mammals by species that may be taken by pile
driving were calculated based on distance to the marine mammal
threshold criteria, days of driving, and the estimated density of each
species in the ZOI, for the species that density could be determined.
The distances to the relevant Level A and B zones are listed above in
Table 8. Because the sizes of piles, types of piles, or installation
methods to be used are unknown at this time, the take estimate
[[Page 15813]]
has been prepared based on a worst case scenario. The Level B take
estimate is based on 60 days of pile driving to install 200 piles, 36
inches (0.91 meters) in diameter, with a vibratory hammer, as this
results in the largest Level B zone for a precautionary approach. The
Level A take estimate is based on 60 days of pile driving to install
200 piles, 36 inches (0.91 meters) in diameter, with an impact hammer,
which has a larger Level A zone than vibratory driving, using of an air
bubble curtain sound attenuation system. The take of each species was
calculated based on species density (Table 9), for the species that
density could be determined, over the entire area of each threshold
criteria zone as shown in Figures 14 and 15 in the application. The
numbers used for take calculation are shown in Table 15.
Table 15--Estimated Take of Marine Mammals From Pile Driving and Pile Removal Activities
--------------------------------------------------------------------------------------------------------------------------------------------------------
Species Species
density density Level B ZOI Level B ZOI Per day Days of Level B Level B
Species (animals/ (animals/ radii area (square take Level pile take take
square square (meters) meters) B driving calculated requested
kilometer) meters)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Harbor Seal.................................. 3.96 3.96E-06 2,000 9101027.61 36.01 60 2160.77 2161
Sea Lion..................................... 0.16 1.61E-07 2,000 9101027.61 1.47 60 87.92 88
Harbor Porpoise.............................. 0.17 1.67E-07 2,000 9101027.61 1.52 60 91.19 91
Bottlenose Dolphin........................... NA NA 2,000 9101027.61 NA 60 NA 30
Elephant Seal................................ NA NA 2,000 9101027.61 NA 60 NA 23
Gray Whale................................... NA NA 2,000 9101027.61 NA 60 NA 4
Fur Seal..................................... NA NA 2,000 9101027.61 NA 60 NA 12
----------------------------------------------------------------------------------------------------------
Total Level B Take....................... ........... ........... ........... .............. ........... ........... ........... 2,392
--------------------------------------------------------------------------------------------------------------------------------------------------------
--------------------------------------------------------------------------------------------------------------------------------------------------------
Species Species
density density Level A ZOI Level A ZOI Per day Days of Level A Level A
Species (animals/ (animals/ radii area (square take Level pile take take
square square (meters) meters) A driving calculated requested
kilometer) meters) \1\
--------------------------------------------------------------------------------------------------------------------------------------------------------
Harbor Seal.................................. 3.96 3.96E-06 130 77907.73574 0.21 60 18.50 0
Sea Lion..................................... 0.16 1.61E-07 9 4302.570961 0.00 60 0.04 0
Harbor Porpoise.............................. 0.17 1.67E-07 290 293195.3612 0.04 60 2.94 0
Bottlenose Dolphin........................... NA NA 9 4302.570961 NA 60 NA 0
Elephant Seal................................ NA NA 130 77907.73574 NA 60 NA 0
Gray Whale................................... NA NA 243 215669.2122 NA 60 NA 0
Fur Seal..................................... NA NA 9 4302.570961 NA 60 NA 0
----------------------------------------------------------------------------------------------------------
Total Level A Take \1\................... ........... ........... ........... .............. ........... ........... ........... 0
--------------------------------------------------------------------------------------------------------------------------------------------------------
Caltrans estimates a maximum of 2,392 instances of take by Level B
harassment may occur to seven stocks of marine mammal during pile-
driving activities (Table 15). These individuals will be exposed
temporarily to continuous (vibratory pile driving and removal) sounds
greater than 120 dB rms and impulse (impact driving) sounds greater
than 160 dB rms. The majority of the animals taken by Level B
harassment will be harbor seals (Table 15), the most numerous marine
mammals in the project area. Although Level A take of marine mammals
was calculated based on distances to the threshold, density of the
species, and duration of the activity; Caltrans does not anticipate any
individuals will be taken by Level A harassment. With proposed
monitoring and establishment of shutdown zones, discussed in the
Proposed Mitigation section below, Caltrans proposes to avoid Level A
harassment of marine mammals.
The number of takes requested by Caltrans are based on a
calculation of marine mammal density multiplied by the daily isopleth
multiplied by the number of days of pile driving. However, due to
variability in sightings of northern elephant seal, northern fur seal,
bottlenose dolphin, and gray whale, take estimates were adjusted using
species specific monitoring data detailed below.
Northern Elephant Seal: Based on low number of elephant seal
sightings in the project area, Caltrans anticipates that very few if
any elephant seals would be exposed to continuous sounds greater than
120 dB rms and impulse sounds greater than 160 dB rms during pile
driving. No elephant seals have been observed in the immediate project
vicinity. However, the number of elephant seals that may enter and or
stand in the Bay in a given year is highly variable; dependent of
changes in oceanographic conditions, effecting water temperature and
prey availability. Further, the size of the Level B harassment zone is
large, extending 2,000 meters (6,562 feet) from the pile driving site.
Pile driving may take place for up to 60 days and many of the driving
days would be consecutive. Should an elephant seal or multiple elephant
seals be in the vicinity of the project area for multiple days they
could be taken several times. To ensure Caltrans has coverage for the
incidental take of any species with the potential to be present in the
project area, we are proposing to authorize take of 12 elephant seals
by Level B harassment during pile driving activities (Table 15). This
equates to the take of one elephant seal during 20 percent of the
driving days.
Northern fur seal: No fur seals have been observed in the immediate
project vicinity. Should a fur seal or multiple fur seals be in the
vicinity of the project area for multiple days they could be taken
several times. To ensure Caltrans has necessary coverage for occasion
fur seals in the area, we propose to authorize take of up to six
northern fur seals by Level B harassment during pile driving activities
(Table 15). This equates to the take of one elephant seal during 10
percent of the driving days.
Bottlenose dolphin: Only small numbers of bottlenose dolphin occur
in the project vicinity. Until 2016, most bottlenose dolphins in the
Bay were observed in the western Bay, from the Golden Gate Bridge to
Oyster Point and Redwood City, although one individual
[[Page 15814]]
was observed frequently near the former Alameda Air Station (Perlman
2017). As of 2017, the same two individuals have been observed
regularly near Alameda (Keener, pers. comm., 2017) are likely pass by
the project area. If additional individuals begin using this eastern
area of the Bay, the number of bottlenose dolphin sightings near the
project area will likely increase. It is possible that the same two
resident bottlenose dolphins and or additional individuals could be
taken multiple times during the up to 60 days of pile driving.
Therefore, Caltrans is requesting authorization for the take of 90
bottlenose dolphins by Level B harassment during pile driving
activities. This equates to the take of 1.5 bottlenose dolphins during
each day of pile driving.
Gray whale: No gray whales have been observed within 2,000 meters
(6,562 feet) of the project area, but they have been observed just
north of Treasure Island and southwest of Oakland Middle Harbor.
According to TMMC, two to six gray whales enter the Bay each year in
late winter through spring (February through April), presumably to
feed. Caltrans wants to ensure that the project has coverage for the
incidental take of any species with the potential to be present in the
project area. Therefore, Caltrans is requesting authorization for the
take of 4 grey whales by Level B harassment during pile driving
activities.
Table 16--Combined Total Take Requested for Pier Implosion and Pile-Driving Activities
----------------------------------------------------------------------------------------------------------------
Pier implosion Level B
harassment take \1\ Pile driving Requested take
-------------------------------- Level B Total Level B as percent of
Species Temporary harassment harassment stock
Behavioral threshold take \1\ take \1\ abundance
response shift
----------------------------------------------------------------------------------------------------------------
Pacific Harbor Seal............. 20 10 2,161 2,191 7
California Sea Lion............. 4 3 88 95 .03
Northern Elephant Seal.......... 2 1 12 15 .01
Northern Fur Seal............... 2 1 6 9 .06
Harbor Porpoise................. 10 8 91 109 1.1
Bottlenose Dolphin.............. 4 2 30 36 8
Gray Whale...................... 0 0 4 4 .02
----------------------------------------------------------------------------------------------------------------
Proposed Mitigation
In order to issue an IHA under Section 101(a)(5)(D) of the MMPA,
NMFS must set forth the permissible methods of taking pursuant to such
activity, and other means of effecting the least practicable impact on
such species or stock and its habitat, paying particular attention to
rookeries, mating grounds, and areas of similar significance, and on
the availability of such species or stock for taking for certain
subsistence uses (latter not applicable for this action). NMFS
regulations require applicants for incidental take authorizations to
include information about the availability and feasibility (economic
and technological) of equipment, methods, and manner of conducting such
activity or other means of effecting the least practicable adverse
impact upon the affected species or stocks and their habitat (50 CFR
216.104(a)(11)).
In evaluating how mitigation may or may not be appropriate to
ensure the least practicable adverse impact on species or stocks and
their habitat, as well as subsistence uses where applicable, we
carefully consider two primary factors:
(1) The manner in which, and the degree to which, the successful
implementation of the measure(s) is expected to reduce impacts to
marine mammals, marine mammal species or stocks, and their habitat.
This considers the nature of the potential adverse impact being
mitigated (likelihood, scope, range). It further considers the
likelihood that the measure will be effective if implemented
(probability of accomplishing the mitigating result if implemented as
planned) the likelihood of effective implementation (probability
implemented as planned); and
(2) the practicability of the measures for applicant
implementation, which may consider such things as cost, impact on
operations, and, in the case of a military readiness activity,
personnel safety, practicality of implementation, and impact on the
effectiveness of the military readiness activity.
Mitigation for Marine Mammals and Their Habitat
Pier Implosions--The decision to combine two smaller piers into
single, sequential blast events will further reduce potential impacts
on marine mammals. This will allow faster completion of the project and
will reduce the total number of pier implosion events (days where pier
implosions occur).
BAS--As described previously in this document, a BAS will be used
around both piers during the implosion. Based on the results of
acoustic monitoring for the previous pier implosions, BAS performance
is anticipated to provide approximately 70 to 80 percent attenuation of
implosion-related pressure waves.
Implosion shutdown zone--During the implosion of Piers E19 and E20,
a project-specific monitoring plan will be implemented to avoid the
potential for individual exposure to Level A harassment, and to
document the number and species potentially exposed to Level B
harassment. This plan will be similar to the Marine Foundation Removal
Project Final Biological Monitoring Program, previously approved by
NMFS, that was implemented during the implosions of Piers E6 to E18. In
particular, monitors will observe the shutdown zone and will delay the
implosion if any individuals are within this zone. The same procedure
was implemented successfully for the implosions of Piers E3 through
E18, and no marine mammals were exposed to SPLs above the Level A or
mortality threshold criteria. This project-specific monitoring plan
will be transmitted to NMFS before the implosions, for review and
concurrence.
Pile driving--All steel pipe piles initially will be installed with
a vibratory hammer. The vibratory hammer will be used to drive the
majority of the total pile lengths. In the event that a pipe pile is
installed entirely with a vibratory hammer, it still will be subject to
final proof testing with an impact hammer. A maximum of 10 percent of
the piles installed completely with a vibratory hammer may be proof-
tested with an impact hammer, without
[[Page 15815]]
the use of a marine pile-driving energy attenuator. Proofing of piles
will be limited to a maximum of two piles per day, for less than 1
minute per pile, administering a maximum of 20 blows per pile. Although
both vibratory and impact pile driving have the potential to affect
marine mammals, impact driving is expected to generate higher SPLs.
Requiring the use of the vibratory hammer will reduce the duration of
impact driving and potential exposure to higher SPLs.
Pile driving energy attenuator--Use of a marine pile-driving energy
attenuator (i.e., air bubble curtain system), or other equally
effective sound attenuation method (e.g., dewatered cofferdam), will be
required by Caltrans during impact driving of all steel pipe piles
(with the exception of pile proof-testing) and during impact driving of
0.91-meter (36-inch) diameter concrete piles. Requiring the use of
sound attenuation will reduce SPLs and the size of the ZOIs for Level A
and Level B harassment.
Pile Driving Shutdown Zone--Before the start of impact pile-driving
activities, the shutdown zones will be established. The shutdown zones
are intended to include all areas where the underwater SPLs are
anticipated to equal or exceed thresholds for injury--PTS Level A
harassment thresholds for the specific species hearing groups, shown in
Table 3. NMFS-approved observers will survey the shutdown zones for 30
minutes before pile-driving activities start. If marine mammals are
found within the shutdown zones, pile driving will be delayed until the
animal has moved out of the shutdown zone, either verified through
sighting by an observer or by waiting until enough time has elapsed
without a sighting, 15 minutes for pinnipeds and small cetaceans
(harbor porpoise and bottlenose dolphin), and 30 minutes for gray
whale, to be able to assume that the animal has moved beyond the zone.
With implementation of this avoidance and minimization measure,
exposure of marine mammals to SPLs that can result in PTS Level A
harassment will be avoided.
A 10 meter shutdown zone for all marine mammals will also be
implemented for in-water heavy machinery work that is not pile driving
or pier implosion. Similarly, if a marine mammal for which take is not
authorized is seen within the monitoring zone, operations will cease
until the animal is seen leaving the zone or until 15 minutes have
passed.
Based on our evaluation of the applicant's proposed measures, NMFS
has preliminarily determined that the proposed mitigation measures
provide the means effecting the least practicable impact on the
affected species or stocks and their habitat, paying particular
attention to rookeries, mating grounds, and areas of similar
significance.
Proposed Monitoring and Reporting
In order to issue an IHA for an activity, Section 101(a)(5)(D) of
the MMPA states that NMFS must set forth, requirements pertaining to
the monitoring and reporting of such taking. The MMPA implementing
regulations at 50 CFR 216.104(a)(13) indicate that requests for
authorizations must include the suggested means of accomplishing the
necessary monitoring and reporting that will result in increased
knowledge of the species and of the level of taking or impacts on
populations of marine mammals that are expected to be present in the
proposed action area. Effective reporting is critical both to
compliance as well as ensuring that the most value is obtained from the
required monitoring.
Monitoring and reporting requirements prescribed by NMFS should
contribute to improved understanding of one or more of the following:
Occurrence of marine mammal species or stocks in the area
in which take is anticipated (e.g., presence, abundance, distribution,
density);
Nature, scope, or context of likely marine mammal exposure
to potential stressors/impacts (individual or cumulative, acute or
chronic), through better understanding of: (1) Action or environment
(e.g., source characterization, propagation, ambient noise); (2)
affected species (e.g., life history, dive patterns); (3) co-occurrence
of marine mammal species with the action; or (4) biological or
behavioral context of exposure (e.g., age, calving or feeding areas);
Individual marine mammal responses (behavioral or
physiological) to acoustic stressors (acute, chronic, or cumulative),
other stressors, or cumulative impacts from multiple stressors;
How anticipated responses to stressors impact either: (1)
Long-term fitness and survival of individual marine mammals; or (2)
populations, species, or stocks;
Effects on marine mammal habitat (e.g., marine mammal prey
species, acoustic habitat, or other important physical components of
marine mammal habitat); and
Mitigation and monitoring effectiveness.
Visual Marine Mammal Observations
Caltrans will collect sighting data and behavioral responses to
construction for marine mammal species observed in the region of
activity during the period of activity. All protected species observers
(PSOs) will be trained in marine mammal identification and behaviors
and are required to have no other construction-related tasks while
conducting monitoring. A minimum of two PSOs will be required for all
pile driving activities. Caltrans will establish shutdown zones,
similar to those detailed in Table 8, as well as a monitoring zone of
2,000 meters for all marine mammals. Caltrans will monitor the shutdown
zone and monitoring zone 30 minutes before, during, and 30 minutes
after pile driving, with observers located at the best practicable
vantage points. Based on our requirements, Caltrans would implement the
following procedures for pile driving:
PSOs would be located at the best vantage point(s) in
order to properly see the entire shutdown zone and as much of the
disturbance zone as possible;
During all observation periods, observers will use
binoculars and the naked eye to search continuously for marine mammals;
If the shutdown zones are obscured by fog or poor lighting
conditions, pile driving at that location will not be initiated until
that zone is visible. Should such conditions arise while impact driving
is underway, the activity would be halted; and
The shutdown zone and observable portion of the monitoring
zone around the pile will be monitored for the presence of marine
mammals 30 min before, during, and 30 min after any pile driving
activity.
Data Collection
We require that observers use approved data forms. Among other
pieces of information, Caltrans will record detailed information about
any implementation of shutdowns, including the distance of animals to
the pile and description of specific actions that ensued and resulting
behavior of the animal, if any. In addition, Caltrans will attempt to
distinguish between the number of individual animals taken and the
number of incidences of take. We require that, at a minimum, the
following information be collected on the sighting forms:
Date and time that monitored activity begins or ends;
Construction activities occurring during each observation
period;
Weather parameters (e.g., percent cover, visibility);
[[Page 15816]]
Water conditions (e.g., sea state, tide state);
Species, numbers, and, if possible, sex and age class of
marine mammals;
Description of any observable marine mammal behavior
patterns, including bearing and direction of travel, and if possible,
the correlation to SPLs;
Distance from pile driving activities to marine mammals
and distance from the marine mammals to the observation point;
Description of implementation of mitigation measures
(e.g., shutdown or delay);
Locations of all marine mammal observations; and
Other human activity in the area.
Reporting
A draft report would be submitted to NMFS within 90 days of the
completion of marine mammal monitoring, or 60 days prior to the
requested date of issuance of any future IHA for projects at the same
location, whichever comes first. The report will include marine mammal
observations pre-activity, during-activity, and post-activity during
pile driving days, and will also provide descriptions of any behavioral
responses to construction activities by marine mammals and a complete
description of all mitigation shutdowns and the results of those
actions and an extrapolated total take estimate based on the number of
marine mammals observed during the course of construction. A final
report must be submitted within 30 days following resolution of
comments on the draft report.
Negligible Impact Analysis and Determination
NMFS has defined negligible impact 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 (50 CFR 216.103). A
negligible impact finding is based on the lack of likely adverse
effects on annual rates of recruitment or survival (i.e., population-
level effects). An estimate of the number of takes alone is not enough
information on which to base an impact determination. In addition to
considering estimates of the number of marine mammals that might be
``taken'' through harassment, NMFS considers other factors, such as the
likely nature of any responses (e.g., intensity, duration), the context
of any responses (e.g., critical reproductive time or location,
migration), as well as effects on habitat, and the likely effectiveness
of the mitigation. We also assess the number, intensity, and context of
estimated takes by evaluating this information relative to population
status. Consistent with the 1989 preamble for NMFS's implementing
regulations (54 FR 40338; September 29, 1989), the impacts from other
past and ongoing anthropogenic activities are incorporated into this
analysis via their impacts on the environmental baseline (e.g., as
reflected in the regulatory status of the species, population size and
growth rate where known, ongoing sources of human-caused mortality, or
ambient noise levels).
Pile driving and pier implosion activities associated from the
Caltrans project, as outlined previously, have the potential to disturb
or displace marine mammals. Specifically, the specified activities may
result in take, in the form of Level B harassment (TTS and behavioral
disturbance), from underwater sounds generated from pier implosions and
pile driving. Potential takes could occur if individuals of these
species are present in the ensonified zone when pile driving or
implosion occurs. A few marine mammals could experience TTS if they
occur within the Level B TTS zone. However, TTS is a temporary loss of
hearing sensitivity when exposed to loud sound, and the hearing
threshold is expected to recover completely within minutes to hours.
Therefore, it is not considered an injury. In addition, even if an
animal receives a TTS, the TTS would be a one-time event from a brief
impulse noise (about 5 seconds), making it unlikely that the TTS would
lead to PTS. If an animal undergoes a TTS from pier implosion, it is
likely to recover quickly as there is only one implosion event
proposed. Finally, there is no critical habitat or other biologically
important areas in the vicinity of Caltrans' proposed controlled
implosion areas (Calambokidis et al., 2015).
No serious injury or mortality is anticipated given the nature of
the activities and measures designed to minimize the possibility of
injury to marine mammals. The potential for these outcomes is minimized
through the construction method and the implementation of the planned
mitigation measures. Specifically, Caltrans proposes to use a blast
attenuation system for the pier implosion, which it has previously used
successfully. For pile driving activities, vibratory and impact hammers
will be the primary methods of pier installation. Impact pile driving
produces short, sharp pulses with higher peak levels and much sharper
rise time to reach those peaks. If impact driving is necessary,
implementation of soft start and shutdown zones significantly reduces
any possibility of injury. Given sufficient ``notice'' through use of
soft start (for impact driving), marine mammals are expected to move
away from a sound source that is annoying prior to it becoming
potentially injurious. Caltrans will use a minimum of two PSOs
stationed strategically to increase detectability of marine mammals,
enabling a high rate of success in implementation of shutdowns to avoid
injury.
Caltrans' proposed activities are localized and of relatively short
duration (June to November). This duration does not overlap with
breeding, pupping, or other biologically significant events for marine
mammal species in the area. The project area is also very limited in
scope spatially, as all work is concentrated on the edges of a single
bridge expanse. These localized and short-term noise exposures may
cause short-term behavioral modifications in seven marine mammal
species. Moreover, the proposed mitigation and monitoring measures are
expected to further reduce the likelihood of injury, as it is unlikely
an animal would remain in close proximity to the sound source with
small Level A isopleths. While the project area is known to be
frequented by harbor seals and California sea lions, it is not an
established breeding ground for local populations.
The project also is not expected to have significant adverse
effects on affected marine mammals' habitat. The project activities
would not modify existing marine mammal habitat for a significant
amount of time. The activities may cause some fish to leave the area of
disturbance, thus temporarily impacting marine mammals' foraging
opportunities in a limited portion of the foraging range. However,
because of the short duration of the activities and the relatively
small area of the habitat that may be affected, and the decreased
potential of prey species to be in the Project area during the
construction work window, the impacts to marine mammal habitat are not
expected to cause significant or long-term negative consequences.
Effects on individuals that are taken by Level B harassment, on the
basis of reports in the literature as well as monitoring from other
similar activities, will likely be limited to temporary reactions such
as increased swimming speeds, increased surfacing time, flushing, or
decreased foraging (if such activity were occurring) (e.g., Thorson and
Reyff 2006; Lerma 2014). Most likely, individuals will simply move
[[Page 15817]]
away from the sound source and be temporarily displaced from the areas
of pile driving and implosions. Thus, even repeated Level B harassment
of some small subset of the overall stock is unlikely to result in any
significant realized decrease in fitness for the affected individuals,
and thus would not result in any adverse impact to the stock as a
whole. For some stocks, such as harbor seal, more animal presence has
increased in recent years, despite Caltrans' work in the area.
In summary and as described above, the following factors primarily
support our preliminary determination that the impacts resulting from
this activity are not expected to adversely affect the species or stock
through effects on annual rates of recruitment or survival:
No mortality is anticipated or authorized;
No more than 10 individuals per species are expected to
incur TTS during pier implosion. No TTS is expected to occur during
pile driving. The size of the zones in which TTS is expected to occur
are small and will be heavily monitored per the measures outlined above
in the Proposed Monitoring section;
Level B harassment may consist of temporary modifications
in behavior (e.g. temporary avoidance of habitat or changes in
behavior);
The lack of important feeding, pupping, or other
biologically significant areas in the action area during the
construction window;
The small impact area relative to species range size;
Mitigation is expected to minimize the likelihood and
severity of the level of harassment; and
The small percentage of the stock that may be affected by
project activities (< eight percent for all stocks).
Based on the analysis contained herein of the likely effects of the
specified activity on marine mammals and their habitat, and taking into
consideration the implementation of the proposed monitoring and
mitigation measures, NMFS preliminarily finds that the total marine
mammal take from the proposed activity will have a negligible impact on
all affected marine mammal species or stocks.
Small Numbers
As noted above, only small numbers of incidental take may be
authorized under Section 101(a)(5)(D) of the MMPA for specified
activities other than military readiness activities. The MMPA does not
define small numbers and so, in practice, where estimated numbers are
available, NMFS compares the number of individuals taken to the most
appropriate estimation of abundance of the relevant species or stock in
our determination of whether an authorization is limited to small
numbers of marine mammals. Additionally, other qualitative factors may
be considered in the analysis, such as the temporal or spatial scale of
the activities.
Table 16 above details the number of individuals that could be
exposed to received noise levels that could cause TTS or Level B
harassment for the proposed work at the project site relative to the
total stock abundance. The numbers of animals authorized to be taken
for all species would be considered small relative to the relevant
stocks or populations even if each estimated instance of take occurred
to a new individual. The total percent of the population (if each
instance was a separate individual) for which take is requested is less
than eight percent for all stocks (Table 16). Based on the analysis
contained herein of the proposed activity (including the proposed
mitigation and monitoring measures) and the anticipated take of marine
mammals, NMFS preliminarily finds that small numbers of marine mammals
will be taken relative to the population size of the affected species
or stocks.
Unmitigable Adverse Impact Analysis and Determination
There are no relevant subsistence uses of the affected marine
mammal stocks or species implicated by this action. Therefore, NMFS has
preliminarily determined that the total taking of affected species or
stocks would not have an unmitigable adverse impact on the availability
of such species or stocks for taking for subsistence purposes.
Endangered Species Act (ESA)
Section 7(a)(2) of the Endangered Species Act of 1973 (ESA: 16
U.S.C. 1531 et seq.) requires that each Federal agency insure that any
action it authorizes, funds, or carries out is not likely to jeopardize
the continued existence of any endangered or threatened species or
result in the destruction or adverse modification of designated
critical habitat. To ensure ESA compliance for the issuance of IHAs,
NMFS consults internally, in this case with the West Coast Region
Protected Resources Division Office, whenever we propose to authorize
take for endangered or threatened species.
No incidental take of ESA-listed species is proposed for
authorization or expected to result from this activity. Therefore, NMFS
has determined that formal consultation under section 7 of the ESA is
not required for this action.
Proposed Authorization
As a result of these preliminary determinations, NMFS proposes to
issue an IHA to Caltrans for conducting pier implosion and pile driving
activity at the San Francisco-Oakland Bay Bridge from May 2018-April
2019, provided the previously mentioned mitigation, monitoring, and
reporting requirements are incorporated. This section contains a draft
of the IHA itself. This section contains a draft of the IHA itself. The
wording contained in this section is proposed for inclusion in the IHA
(if issued).
1. This Incidental Harassment Authorization (IHA) is valid for 1
year from May 15, 2018 through April 14, 2019.
2. This IHA is valid only for pier implosion and pile driving
activities associated with the San Francisco--Oakland Bay Bridge.
3. General Conditions
(a) A copy of any issued LOA or IHA must be in the possession of
the applicant, its designees, and work crew personnel operating under
the authority of the issued LOA.
(b) The species authorized for taking are summarized in Table 17.
(c) The taking, by Level B harassment only, is limited to the
species listed in condition 3(b). See Table 17 for numbers of take
authorized.
Table 17--Authorized Take Numbers
------------------------------------------------------------------------
Total Level B
Species harassment
take
------------------------------------------------------------------------
Pacific Harbor Seal..................................... 2,161
California Sea Lion..................................... 88
Northern Elephant Seal.................................. 12
Northern Fur Seal....................................... 6
Harbor Porpoise......................................... 91
Bottlenose Dolphin...................................... 30
Gray Whale.............................................. 4
------------------------------------------------------------------------
(d) The taking by injury (Level A harassment), serious injury, or
death of the species listed in condition 3(c) of the Authorization or
any taking of any other species of marine mammal is prohibited and may
result in the modification, suspension, or revocation of this IHA,
unless authorization of take by Level A harassment is listed in
condition 3(b) of this Authorization.
4. Mitigation Measures
The holder of this Authorization is required to implement the
following mitigation measures.
(a) In-water pile driving and pile removal activities and the
controlled
[[Page 15818]]
implosion of Piers E19 and E20 shall only be conducted during daylight
hours and with enough time for pre and post activity monitoring, and
with good visibility when the largest exclusion zone can be visually
monitored.
(b) For controlled implosion of Piers E19 and E20, Caltrans shall
install and use a Blast Attenuation System (BAS) prior to demolition to
reduce the shockwave from the implosion.
(c) Establishment of shutdown zones
(i) For in-water heavy machinery work (such as debris removal or
setting up the BAS), a minimum 10 m shutdown zone shall be implemented.
If a marine mammal comes within 10 m of such operations, operations
shall cease and vessels shall reduce speed to the minimum level
required to maintain steerage and safe working conditions. This type of
work could include (but is not limited to) the following activities:
(1) Vibratory pile driving; (2) movement of the barge to the pile
location; (3) positioning of the pile on the substrate via a crane
(i.e., stabbing the pile); (4) removal of the pile from the water
column/substrate via a crane (i.e., deadpull); or (5) the placement of
sound attenuation devices around the piles.
(ii) For controlled implosion and associated test blasting, as well
as pile driving, Caltrans shall establish monitoring zones that are
appropriate to specific marine mammal functional hearing groups for
each implosion scenario (See Tables 18 & 19 below).
Table 18--Shutdown and Monitoring Zones for Pier Implosions
----------------------------------------------------------------------------------------------------------------
Level B behavioral Level A injury and
Species/group response monitoring Level B TTS monitoring mortality exclusion
zone zone zone
----------------------------------------------------------------------------------------------------------------
Pinniped and Dolphin................. 290 meters (951 feet).. 200 meters (656 feet).. 70 meters (230 feet).
Harbor Porpoise...................... 1,220 meters (4,003 830 meters (2,723 feet) 290 meters (951 feet).
feet).
----------------------------------------------------------------------------------------------------------------
Table 19--Shutdown and Monitoring Zones for Pile Driving
--------------------------------------------------------------------------------------------------------------------------------------------------------
Level A pinniped Level A porpoise
Pile type Installation method Attenuation system and dolphin and whale Level B monitoring
exclusion zone exclusion zone zone-- all species
--------------------------------------------------------------------------------------------------------------------------------------------------------
H-Pile........................... Vibratory................. None...................... 2 meters (7 feet).. 1 meter (3 feet)... 1,000 meters (3,280
feet).
24-inch Steel Pipe Pile.......... Vibratory................. None...................... 8 meters (26 feet). 19 meters (62 feet) 2,000 meters (6,562
feet).
36-inch Steel Pipe Pile.......... Vibratory................. None...................... 20 meters (98 feet) 49 meters (161 2,000 meters (6,562
feet). feet).
H-Pile........................... Impact.................... None...................... 18 meters (59 feet) 39 meters (128 100 meters (328
feet). feet).
24-inch Steel Pipe Pile.......... Impact.................... Bubble Curtain............ 68 meters (223 151 meters (495 215 meters (705
feet). feet). feet).
36-inch Steel Pipe Pile.......... Impact.................... Bubble Curtain............ 130 meters (427 290 meters (951 541 meters (1,775
feet). feet). feet).
24-inch Concrete Pile............ Impact.................... None...................... 52 meters (171 115 meters (377 46 meters (151
feet). feet). feet).
36-inch Concrete Pile............ Impact.................... Bubble Curtain............ 57 meters (187 127 meters (417 117 meters (384
feet). feet). feet).
--------------------------------------------------------------------------------------------------------------------------------------------------------
(d) Shutdown Zone Monitoring for Mitigation Measures
(i) Pre-activity monitoring shall take place from 30 minutes prior
to initiation of activity and post-activity monitoring shall continue
through 30 minutes post-completion for construction activity and 60
minutes post-completion for implosion activity. Pile driving may
commence at the end of the 30-minute pre-activity monitoring period,
provided observers have determined that the shutdown zone is clear of
marine mammals, which includes delaying start of pile driving
activities if a marine mammal is sighted in the zone, as described in
Table 19 above.
(ii) A determination that the shutdown zone is clear must be made
during a period of good visibility (i.e., the entire shutdown zone and
surrounding waters must be visible to the naked eye).
(iii) If a marine mammal approaches or enters the shutdown zone
during activities or pre-activity monitoring, all pile driving or
implosion activities at that location shall be halted or delayed,
respectively. If activity is halted or delayed due to the presence of a
marine mammal, the activity may not resume or commence until either the
animal has voluntarily left and been visually confirmed beyond the
shutdown zone and 30 minutes have passed without re-detection of the
animal. Pile driving activities include the time to install or remove a
single pile or series of piles, as long as the time elapsed between
uses of the pile driving equipment is no more than thirty minutes.
(iv) Caltrans shall use soft start techniques when impact pile
driving. Soft start requires contractors to provide an initial set of
strikes at reduced energy, followed by a thirty-second waiting period,
then two subsequent reduced energy strike sets. Soft start shall be
implemented at the start of each day's impact pile driving and at any
time following cessation of impact pile driving for a period of thirty
minutes or longer.
(v) If the number of authorized takes are reached, Caltrans will
shut down if a marine mammal is sighted within or approaching the
monitoring zone.
(vi) If a species for which take is not authorized is sighted
within or approaching the monitoring zone, Caltrans will shut down.
5. Monitoring
(i) The holder of this Authorization is required to conduct marine
mammal monitoring during pier implosion and pile driving and removal
activities. Marine mammal monitoring and reporting shall be conducted
in accordance with the monitoring measures in the application.
(a) For all pile driving activities, a minimum of two protected
species observer (PSOs) shall be required, with at least one PSO
stationed at the active pile driving rig or at the best vantage
point(s) practicable to monitor the shutdown zone for marine mammals
and implement shutdown or delay procedures when applicable through
communication with the equipment operator. Other PSOs should be
stationed at the best vantage point(s) practicable to observe the
monitoring zone.
(b) For all pier implosion activities, a minimum of eight PSOs will
be required. One PSO will be designated as the Lead PSO, who will
receive updates from other PSOs on the presence or absence of marine
mammals within the PSO. This Lead PSO will notify the Environmental
Compliance Manager of a cleared shutdown zone before the start of the
implosion(s). PSOs shall be positioned near the edge of each of the
threshold criteria zones and shall utilize
[[Page 15819]]
boats, barges, and bridge piers and roadway.
(ii) Caltrans shall conduct briefings for construction supervisors
and crews, the monitoring team, and Caltrans staff prior to the start
of all pile driving activity, and when new personnel join the work, in
order to explain responsibilities, communication procedures, the marine
mammal monitoring protocol, and operational procedures.
(iii) Monitoring of pile driving shall be conducted by qualified
PSOs (see below), who shall have no other assigned tasks during
monitoring periods. Caltrans shall adhere to the following conditions
when selecting observers:
Independent PSOs shall be used (i.e., not construction
personnel);
At least one PSO must have prior experience working as a
marine mammal observer during construction activities;
Other PSOs may substitute education (degree in biological
science or related field) or training for experience;
Where a team of three or more PSOs are required, a lead
observer or monitoring; coordinator shall be designated. The lead
observer must have prior experience working as a marine mammal observer
during construction; and
Caltrans shall submit PSO CVs for approval by NMFS;
Caltrans shall ensure that observers have the following additional
qualifications:
Ability to conduct field observations and collect data
according to assigned protocols;
Experience or training in the field identification of
marine mammals, including the identification of behaviors;
Sufficient training, orientation, or experience with the
construction operation to provide for personal safety during
observations;
Writing skills sufficient to prepare a report of
observations including but not limited to the number and species of
marine mammals observed; dates and times when in-water construction
activities were conducted; dates, times, and reason for implementation
of mitigation (or why mitigation was not implemented when required);
and marine mammal behavior; and
Ability to communicate orally, by radio or in person, with
project personnel to provide real-time information on marine mammals
observed in the area as necessary.
(iv) If a species for which authorization has not been granted, or
a species for which authorization has been granted but the authorized
takes are met, is observed approaching or within the monitoring zone
(2,000 m), activities must shut down immediately using delay and shut-
down procedures. Activities must not resume until the animal has been
confirmed to have left the area or the observation time period has
elapsed.
6. Reporting
(i) Caltrans shall submit a draft report to NMFS [not later than 90
days following the end of construction activities OR 60 days prior to
the issuance of any subsequent IHA for the project]. Caltrans shall
provide a final report within 30 days following resolution of NMFS'
comments on the draft report. Reports shall contain, at minimum, the
following:
Date and time that monitored activity begins and ends for
each day conducted (monitoring period);
Construction activities occurring during each daily
observation period, including how many and what type of piles driven;
Deviation from initial proposal in pile numbers, pile
types, average driving times, etc.;
Weather parameters in each monitoring period (e.g., wind
speed, percent cloud cover, visibility);
Water conditions in each monitoring period (e.g., sea
state, tide state);
For each marine mammal sighting:
[cir] Species, numbers, and, if possible, sex and age class of
marine mammals;
[cir] Description of any observable marine mammal behavior
patterns, including bearing and direction of travel and distance from
pile driving activity;
[cir] Location and distance from pile driving activities to marine
mammals and distance from the marine mammals to the observation point;
and
[cir] Estimated amount of time that the animals remained in the
Level B zone;
Description of implementation of mitigation measures
within each monitoring period (e.g., shutdown or delay);
Other human activity in the area within each monitoring
period
A summary of the following:
[cir] Total number of individuals of each species detected within
the Level B Zone, and estimated as taken if correction factor
appropriate;
[cir] Total number of individuals of each species detected within
the Level A Zone and the average amount of time that they remained in
that zone; and
[cir] Daily average number of individuals of each species
(differentiated by month as appropriate) detected within the the Level
B Zone, and estimated as taken, if appropriate.
(ii) In the unanticipated event that the specified activity clearly
causes the take of a marine mammal in a manner prohibited by this IHA,
such as a serious injury or mortality, Caltrans shall immediately cease
the specified activities and report the incident to the Office of
Protected Resources, NMFS, and the West Coast Regional Stranding
Coordinator. The report must include the following information:
a. Time and date of the incident;
b. Description of the incident;
c. Environmental conditions (e.g., wind speed and direction,
Beaufort sea state, cloud cover, and visibility);
d. Description of all marine mammal observations in the 24 hours
preceding the incident;
e. Species identification or description of the animal(s) involved;
f. Fate of the animal(s); and
g. Photographs or video footage of the animal(s).
(iii) Activities shall not resume until NMFS is able to review the
circumstances of the prohibited take. NMFS will work with Caltrans to
determine what measures are necessary to minimize the likelihood of
further prohibited take and ensure MMPA compliance. Caltrans may not
resume their activities until notified by NMFS.
(iv) In the event that the Caltrans discovers an injured or dead
marine mammal, and the lead observer determines that the cause of the
injury or death is unknown and the death is relatively recent (e.g., in
less than a moderate state of decomposition), Caltrans shall
immediately report the incident to the Office of Protected Resources,
NMFS, and the West Coast Regional Stranding Coordinator.
The report must include the same information identified above.
Activities may continue while NMFS reviews the circumstances of the
incident. NMFS will work with Caltrans to determine whether additional
mitigation measures or modifications to the activities are appropriate.
(v) In the event that Caltrans discovers an injured or dead marine
mammal, and the lead observer determines that the injury or death is
not associated with or related to the activities authorized in the IHA
(e.g., previously wounded animal, carcass with moderate to advanced
decomposition, scavenger damage), Caltrans shall report the incident to
the Office of Protected Resources, NMFS, and the West Coast Regional
Stranding Coordinator, NMFS, within 24 hours of the discovery. Caltrans
shall provide photographs or video footage or other documentation of
the stranded animal sighting to NMFS.
[[Page 15820]]
7. This Authorization may be modified, suspended or withdrawn if
the holder fails to abide by the conditions prescribed herein, or if
NMFS determines the authorized taking is having more than a negligible
impact on the species or stock of affected marine mammals.
Request for Public Comments
We request comment on our analyses, the proposed authorization, and
any other aspect of this Notice of Proposed IHA for the proposed pier
implosion and pile driving. We also request comment on the potential
for renewal of this proposed IHA as described in the paragraph below.
Please include with your comments any supporting data or literature
citations to help inform our final decision on the request for MMPA
authorization.
On a case-by-case basis, NMFS may issue a second one-year IHA
without additional notice when (1) another year of identical or nearly
identical activities as described in the Specified Activities section
is planned or (2) the activities would not be completed by the time the
IHA expires and a second IHA would allow for completion of the
activities beyond that described in the Dates and Duration section,
provided all of the following conditions are met:
A request for renewal is received no later than 60 days
prior to expiration of the current IHA;
The request for renewal must include the following:
(1) An explanation that the activities to be conducted beyond the
initial dates either are identical to the previously analyzed
activities or include changes so minor (e.g., reduction in pile size)
that the changes do not affect the previous analyses, take estimates,
or mitigation and monitoring requirements; and
(2) A preliminary monitoring report showing the results of the
required monitoring to date and an explanation showing that the
monitoring results do not indicate impacts of a scale or nature not
previously analyzed or authorized; and
Upon review of the request for renewal, the status of the
affected species or stocks, and any other pertinent information, NMFS
determines that there are no more than minor changes in the activities,
the mitigation and monitoring measures remain the same and appropriate,
and the original findings remain valid.
Dated: April 9, 2018.
Donna S. Wieting,
Director, Office of Protected Resources, National Marine Fisheries
Service.
[FR Doc. 2018-07573 Filed 4-11-18; 8:45 am]
BILLING CODE 3510-22-P