[Federal Register Volume 81, Number 93 (Friday, May 13, 2016)]
[Notices]
[Pages 29890-29907]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2016-11426]
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DEPARTMENT OF THE INTERIOR
Fish and Wildlife Service
[FWS-R7-ES-2016-N036; FF07CAMM00-FX-FXFR133707REG04]
Marine Mammals; Incidental Take During Specified Activities;
Proposed Incidental Harassment Authorization for Northern Sea Otters
From the Southcentral Stock in Cook Inlet, Alaska
AGENCY: Fish and Wildlife Service, Interior.
ACTION: Notice of receipt of application and proposed incidental
harassment authorization; availability of draft environmental
assessment; request for comments.
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SUMMARY: We, the U.S. Fish and Wildlife Service (Service), in response
to a request under the Marine Mammal Protection Act of 1972 (MMPA), as
amended, from BlueCrest Alaska Operating LLC (BlueCrest), propose to
authorize the incidental taking by harassment of small numbers of
northern sea otters from the Southcentral stock in Cook Inlet, Alaska,
from date of issuance--October 31, 2016. BlueCrest has requested this
authorization for their planned oil and gas exploration activities. We
anticipate no take by injury or death and include none in this proposed
authorization, which would be for take by harassment only.
DATES: We will consider comments we receive on or before June 13, 2016.
ADDRESSES:
Document availability: The incidental harassment authorization
request, associated draft environmental assessment, and supporting
documentation, such as Literature Cited, are available for viewing at
http://www.fws.gov/alaska/fisheries/mmm/iha.htm.
Comments submission: You may submit comments on the proposed
incidental harassment authorization and associated draft environmental
assessment by one of the following methods:
U.S. mail or hand-delivery: Public Comments Processing,
Attn: Kimberly Klein, U.S. Fish and Wildlife Service, MS 341, 1011 East
Tudor Road, Anchorage, AK 99503;
Fax: 907-786-3816, attention to Kimberly Klein; or
Email comments to: FW7_AK_Marine_Mammals@fws.gov.
Please indicate to which document, the proposed incidental
harassment authorization, or the draft environmental assessment, your
[[Page 29891]]
comments apply. We will post all hardcopy comments on http://www.fws.gov/alaska/fisheries/mmm/iha.htm.
FOR FURTHER INFORMATION CONTACT: To request copies of the application,
the list of references used in the notice, and other supporting
materials, contact Kimberly Klein, by mail at Marine Mammals
Management, U.S. Fish and Wildlife Service, MS 341, 1011 East Tudor
Road, Anchorage, AK 99503; by email at kimberly_klein@fws.gov; or by
telephone at 1-800-362-5148.
SUPPLEMENTARY INFORMATION: In response to a request under section
101(a)(5)(D) of the Marine Mammal Protection Act of 1972 (MMPA), as
amended, from BlueCrest, we propose to authorize the incidental taking
by harassment of small numbers of northern sea otters from the
Southcentral stock in Cook Inlet, Alaska, from date of issuance--
October 31, 2016. BlueCrest has requested this authorization for their
planned oil and gas exploration activities. We anticipate no take by
injury or death and include none in this proposed authorization, which
would be for take by harassment only.
Executive Summary
Why We Need To Publish an Incidental Harassment Authorization
In November 2015, the Service was petitioned by BlueCrest to
provide authorization for the incidental take by harassment of northern
sea otters (Enhydra lutris kenyoni) under the MMPA. This proposed
authorization is an official document that announces and explains the
Service's draft determination to issue an authorization and our plans
to address any potential impacts of BlueCrest's plans to conduct an oil
and gas production drilling program in lower Cook Inlet on State of
Alaska Oil and Gas Lease 384403 under the program name of Cosmopolitan
State during the open water season of 2016. The proposed authorization
discusses the incidental taking by harassment of small numbers of
northern sea otters from the Southcentral stock in Cook Inlet, Alaska,
from date of issuance--October 31, 2016.
The Effect of This Authorization
The MMPA allows, upon request, the incidental take of small numbers
of marine mammals as part of a specified activity within a specified
geographic region. In this case, the activity is related to oil and gas
development. As part of this authorization, the Service may authorize
incidental take to BlueCrest if we find that the taking would:
Be of small numbers;
Have no more than a ``negligible impact'' on northern sea
otters; and
Not have an ``unmitigable adverse impact'' on the
availability of the species or stock for ``subsistence'' uses.
The Service may stipulate the permissible methods of taking and
require mitigation, monitoring, and reporting of such takings, which
are meant to reduce or minimize negative impacts to the northern sea
otters.
Request for Public Comments
We intend that any final action resulting from this proposal will
be as accurate and as effective as possible. Therefore, we request
comments or suggestions on this proposed authorization. We particularly
seek comments concerning:
(1) Will the proposed authorization including the proposed
activities have a negligible impact on the Southcentral stock of the
northern sea otter?
(2) Will the proposed authorization ensure that an unmitigable
adverse impact on the availability of northern sea otters for
subsistence taking does not occur? and,
(3) Are there any additional provisions we may wish to consider to
ensure the conservation of the Southcentral stock of the northern sea
otter?
You may submit your comments and materials concerning this proposed
authorization by one of the methods listed in the ADDRESSES section. We
will not consider comments sent by email or fax, or to an address not
listed in the ADDRESSES section.
If you submit a comment via FW7_AK_Marine_Mammals@fws.gov, your
entire comment-- including any personal identifying information--may be
available to the public. If you submit a hardcopy comment that includes
personal identifying information, you may request at the top of your
document that we withhold this information from public review. However,
we cannot guarantee that we will be able to do so. We will post all
hardcopy comments on http://www.fws.gov/alaska/fisheries/mmm/iha.htm.
Background
Section 101(a)(5)(D) of the MMPA, as amended (16 U.S.C.
1371(a)(5)(D)), authorizes the Secretary of the Interior to allow, upon
request of a citizen, for periods of not more than 1 year and subject
to such conditions as the Secretary may specify, the incidental but not
intentional taking by harassment of small numbers of marine mammals of
a species or population stock, by such citizens, while engaging in that
activity within that region if the Secretary finds that such harassment
during each period concerned:
(1) Will have a negligible impact on such species or stock, and
(2) Will not have an unmitigable adverse impact on the availability
of such species or stock for taking for subsistence.
As part of the authorization process, we prescribe permissible
methods of taking, and other means of effecting the least practicable
impact on the species or stock and its habitat, and requirements
pertaining to the monitoring and reporting of such takings.
The term ``take,'' as defined by the MMPA, means to harass, hunt,
capture, or kill, or to attempt to harass, hunt, capture, or kill any
marine mammal. Harassment, as defined by the MMPA, means ``any act of
pursuit, torment, or annoyance which (i) has the potential to injure a
marine mammal or marine mammal stock in the wild (the MMPA calls this
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 (the MMPA calls
this Level B harassment).''
The terms ``small numbers,'' ``negligible impact,'' and
``unmitigable adverse impact'' are defined in 50 CFR 18.27, the
Service's regulations governing take of small numbers of marine mammals
incidental to specified activities. ``Small numbers'' is defined as ``a
portion of a marine mammal species or stock whose taking would have a
negligible impact on that species or stock.'' However, we do not rely
on that definition here, as it conflates the terms ``small numbers''
and ``negligible impact,'' which we recognize as two separate and
distinct requirements. Instead, in our small numbers determination, we
evaluate whether the number of marine mammals likely to be taken is
small relative to the size of the overall population. ``Negligible
impact'' is defined 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.'' ``Unmitigable adverse
impact'' is defined as ``an impact resulting from the specified
activity (1) that is likely to reduce the availability of the species
to a level insufficient for a harvest to meet subsistence needs by (i)
causing the marine mammals to abandon or avoid
[[Page 29892]]
hunting areas, (ii) directly displacing subsistence users, or (iii)
placing physical barriers between the marine mammals and the
subsistence hunters; and (2) that cannot be sufficiently mitigated by
other measures to increase the availability of marine mammals to allow
subsistence needs to be met.''
Section 101(a)(5)(D) of the MMPA establishes an expedited process
by which citizens of the United States can apply for an authorization
to incidentally take small numbers of marine mammals where the take
will be limited to harassment. Section 101(a)(5)(D)(iii) establishes a
45-day time limit for Service review of an application, followed by a
30-day public notice and comment period on any proposed authorizations
for the incidental harassment of marine mammals. Within 45 days of the
close of the comment period, we must either issue or deny issuance of
the authorization. We refer to these authorizations as IHAs.
The Service has issued IHAs for sea otters in the past, including
the following:
Northern sea otters: IHAs incidental to airport construction on
Akun Island and hovercraft operation between Akun Island and Akutan,
Alaska (August 27, 2008 (73 FR 50634); June 8, 2010 (75 FR 32497); and
April 1, 2011 (76 FR 18232)); and an IHA to cover the incidental take
of northern sea otters due to previous oil and gas exploration
activities in Cook Inlet, Alaska (August 29, 2014 (79 FR 51584)). None
of these IHAs remain in effect.
Southern sea otters (E.l. nereis): IHAs incidental to construction
activities associated with a tidal wetlands restoration project on the
Elkhorn Slough National Estuarine Research Reserve in Monterey County,
California (July 20, 2010 (75 FR 42121)), and incidental to the
replacement of pier piles and the potable water line at U.S. Coast
Guard Station Monterey in Monterey County, California (September 30,
2014 (79 FR 58796)).
Summary of Request
On November 12, 2015, the Service received a request from BlueCrest
for the nonlethal taking, by harassment, of northern sea otters
(hereafter ``otters'') from the Southcentral stock incidental to plans
to conduct an oil and gas production drilling program in lower Cook
Inlet on State of Alaska Oil and Gas Lease 384403 under the program
name of Cosmopolitan State. The program includes drilling up to three
wells with the total operation time of about 135 days. The exact timing
of the project will be dependent upon rig availability, but will occur
in the summer operating season between April 15 and October 31, 2016.
In 2013, BlueCrest conducted exploratory oil and gas drilling at a
well site in the lower Cook Inlet. Beginning in spring 2016, BlueCrest
proposes to drill two more wells to tap these identified gas layers for
production and a third well to collect geological information. The
proposed BlueCrest drilling operations could harass local sea otters
via its impulsive acoustics from the periods of conductor pipe driving
(CPD) and vertical seismic profiling (VSP) activities. Harassment is a
form of take as defined under the MMPA.
BlueCrest is requesting incidental take authorization for Level B
noise harassment (noise exceeding 160 decibels (dB, all dB levels given
herein are re: 1 [micro]Pa RMS) associated with the oil and gas
drilling activities. Actual Level B ``takes'' will depend upon the
number of sea otters occurring within the 160 dB zone of influence
(ZOI) at the time of seismic activity. BlueCrest does not believe any
Level A injury ``takes'' (noise exceeding 190 dB) are expected with
proposed mitigation measures in place.
A complete copy of BlueCrest's request and supporting documents may
be obtained as specified above in ADDRESSES.
Prior to issuing an IHA in response to this request, the Service
must evaluate the level of industrial activities described in the
application, their associated potential impacts to sea otters, and
their potential effects on the availability of this species for
subsistence use. The information provided by the applicant indicates
that oil and gas activities projected over the next year will encompass
offshore exploration activities. The Service is tasked with analyzing
the impact that lawful industrial activities will have on sea otters
during normal operating procedures.
Description of the Specified Activities
In 2013, BlueCrest, then in partnership with Buccaneer Energy,
conducted exploratory oil and gas drilling at the Cosmopolitan State
#A-1 well site (then called Cosmopolitan State #1). The well
encountered multiple oil and gas zones, including gas zones capable of
production in paying quantities. Beginning in spring 2016, BlueCrest
proposes to drill two more wells (Cosmopolitan State #A-2 and #A-3) to
tap these identified gas layers for production. These directionally
drilled wells have top holes located a few meters from the original
Cosmopolitan State #A-1, and together could feed to a future single
offshore platform. Both #A-2 and #A-3 may involve test drilling into
oil layers. A third well, #B-1, will be located approximately 1.7
kilometer (km) (1 mile (mi)) southeast of the other three wells. This
well will be drilled into oil formations to collect geological
information. After testing, the oil horizons will be plugged and
abandoned, while the gas zones will be suspended pending platform
construction. Refer to Table 1 and Figure 1 for further location
details.
Table 1--Locations of Proposed Cosmopolitan State Well Sites
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Water depth
Well name Latitude Longitude (m)
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Cosmopolitan State #A-1............. N 59[deg]53'13.0'' W 151[deg]52'58.0'' 23.8
Cosmopolitan State #A-2............. N 59[deg]53'13.1'' W 151[deg]52'58.1'' 23.8
Cosmopolitan State #A-3............. N 59[deg]53'13.2'' W 151[deg]52'58.2'' 23.8
Cosmopolitan State #B-1............. N 59[deg]52'12'' W 151[deg]52'17'' 20.7
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Whenever practicable, BlueCrest will use existing infrastructure
and resources found on the Kenai Peninsula and south-central Alaska.
These resources include barge landings, private staging areas,
airstrips, landfills, water supplies, heavy equipment, and personnel.
Most on-shore activity will base from either Kenai or Homer.
BlueCrest proposes to conduct its production and exploratory
drilling using the Spartan 151 drill rig or similar rig (e.g., the
Endeavour). The Spartan 151 is a 150 H class independent leg,
[[Page 29893]]
cantilevered jack-up drill rig with a drilling depth capability of
7,620 meters (m) (25,000 feet (ft)), that can operate in maximum water
depths up to 46 m (150 ft). To maintain safety and work efficiency, the
exploratory drill rigs will be equipped with the following:
A 5,000-, 10,000-, or 15,000-pounds per square inch (psi)
blowout preventer (BOP) stack--for drilling in higher pressure
formations found at greater depths in Cook Inlet;
Sufficient variable deck load to accommodate the increased
drilling loads and tubular for deeper drilling;
Reduced draft characteristics to enable the rig to easily
access shallow water locations;
Riser tensioning system to adequately deal with the
extreme tides/currents in up to 91-m (300-ft) water depth;
Steel hull designed to withstand -10 degrees Celsius to
eliminate the risk of steel failure during operations in Cook Inlet
(i.e., built for North Sea arctic conditions); and
Ability to cantilever over existing platforms for working
on development wells or during plug and abandonment.
[GRAPHIC] [TIFF OMITTED] TN13MY16.003
The Spartan 151 is likely to be moored at Port Graham over the
winter of 2015-2016 where it will undergo maintenance and
winterization. BlueCrest proposes to move the drill rig to the
Cosmopolitan State #B-1 well site at some point after April 15, 2016.
The tow would likely be accomplished within a 48-hour (hr) period. Any
subsequent move will be controlled by the owner of the drilling rig.
The rig will be towed between locations by ocean-going tugs that are
licensed to operate in Cook Inlet and will be conducted in accordance
with State and Federal regulations. Rig moves will be conducted in a
manner to minimize any potential risk regarding safety as well as
cultural or environmental impact.
While under tow to the Cosmopolitan well sites, rig operations will
be monitored by BlueCrest and the drilling contractor management. Very
high frequency radio, satellite, and cellular phone communication
systems will be used while the rig is under tow. Helicopter transport
will also be available. A certified marine surveyor will be monitoring
during rig moves.
The rig will be stocked with most of the drilling supplies required
to complete a full summer program. Deliveries of remaining items,
including crew transfers, will be performed by support vessels and
helicopters.
BlueCrest proposes to use helicopters for project operations. This
may include transportation for personnel, groceries, and supplies.
Helicopter support will
[[Page 29894]]
consist of a twin-turbine Bell 212 (or equivalent) helicopter certified
for instrument flight rules for land and over-water operations.
Helicopter crews and support personnel will be housed in existing Kenai
area facilities. The helicopter will be based at the Kenai Airport and/
or Homer Airport to support rig crew changes and cargo handling. No
helicopter refueling will take place on the rig.
Helicopter flights to and from the rig are expected to average two
per day. Flight routes will follow a direct route to and from the rig
location, and flight heights will be maintained 300 to 450 m (1,000 to
1,500 ft) above ground level to avoid acoustical harassment of marine
mammals (Richardson et al. 1995). The aircraft will be dedicated to the
drilling operation and will be available for service 24 hr/day. A
replacement aircraft will be available when major maintenance items are
scheduled.
Major supplies will be staged on-shore at Kenai. Required supplies
and equipment will be moved from the staging area by contracted supply
vessels and loaded aboard the rig when the rig is established on a
drilling location and will include fuel, drilling water, mud materials,
cement, casing, and well service equipment. Supply vessels will be
outfitted with fire-fighting systems as part of fire prevention and
control as required by Cook Inlet Spill Prevention and Response, Inc.
(CISPRI).
Rig equipment will use diesel fuel or electricity from generators.
Personnel associated with fuel delivery, transfer, and handling will be
knowledgeable of Best Management Practices (BMP) of Industry
(Collectively, the entities, personnel, and companies involved in the
following activities: Oil and gas exploration, development, and
production; oil and gas support services; and associated activities
such as research). BMPs are related to fuel transfer and handling, drum
labeling, secondary containment guidelines, and the use of liners/drip
trays.
When planned and permitted operations are completed, the well will
be suspended according to Alaska Oil and Gas Conservation Commission
regulations. Drilling wastes include drilling fluids, known as mud,
rock cuttings, and formation waters and will be discharged to the Cook
Inlet under an approved Alaska Pollution Discharge Elimination System
(APDES) general permit or sent to an approved waste disposal facility.
Drilling wastes (hydrocarbon) will be delivered to an onshore permitted
location for disposal. BlueCrest will follow BMPs and all stipulations
of the applicable permits for this activity. Fluids and cutting
management does not produce any noise signature to the marine
environment that is not already included in other activities provided
herein.
The project components with a potential for harassment of marine
mammals include:
1. Towing of the jack-up drill rig to and between the Cosmopolitan
well sites;
2. Impact hammering of the drive pipe at the well prior to
drilling; and
3. The VSP operations that may occur at the completion of drilling.
For these activities the primary impact of concern is the effect
the noise generated by these operations could have on local marine
mammals. Underwater noise associated with drilling and rig operation
has already been determined by the National Marine Fisheries Service
(NMFS) of the National Oceanic and Atmospheric Administration (NOAA)
and the Service in prior consultations to have little effect on marine
mammals (based on Marine Acoustics, Inc.'s (2011) acoustical testing of
the Spartan 151 while drilling), thus is not addressed further in this
petition. Helicopters will be used to transport personnel on and off
the drill rig, but any noise-related impacts to sea otters will be
avoided by maintaining 300- to 450-m (1,000- to 1,500-ft) flight
altitudes. The Service has determined that Level B disturbance
harassment of sea otters can occur when the animals are exposed to
underwater noise exceeding 160 dB, regardless of whether the noise is
continuous or impulsive. Towing, CPD, and VSP are the only planned
operations expected to produce underwater noise exceeding 160 dB, and
are the subjects of this petition.
Rig Tow--The jack-up rig would be towed to the first well site (#B-
1) during early spring or summer 2016. It is estimated that the tow
will take about 48 hours to complete. Tows lasting less than a day will
also occur between well sites. Tugs generate their loudest sounds while
towing due to the propeller cavitations. These continuous sounds have
been measured at up to 171 dB at 1-m source (Richardson et al. 1995),
and they are generally emitted at dominant frequencies of well less
than 5 kilohertz (kHz) (Miles et al. 1987, Richardson et al. 1995,
Simmonds et al. 2004). Since it is currently unknown which tugs will be
used to tow the rig on each tow (to and from the well site), and there
are few sound signatures for tugs in general, it is assumed that noise
exceeding 160 dB extends 253 m (830 ft) from the operating tugs (based
on a 171 dB source). The tug's cavitating propellers do not exceed 190
dB at 1-m source, thus they do not represent a Level A injury take
concern.
Drive Pipe Placement--A drive pipe is a relatively short, large-
diameter pipe driven into the sediment prior to the drilling of oil
wells. Drive pipes are usually installed using pile-driving techniques.
BlueCrest proposes to drive approximately 60 m (200 ft below mudline)
of 76.2-cm (30-in) pipe at each well site prior to drilling using a
Delmar D62-22 impact hammer. This hammer has impact weight of 6,200
kilograms (kg) (13,640 pounds (lb)) and reaches a maximum impact energy
of 224 kilonewton-m (165,215 ft-lb) at a drop height of 3.6 m (12 ft).
Illingworth & Rodkin (2014) measured the noise from a hammer operating
from the Endeavour in 2013 and found noise levels exceeding 160 dB out
to 1.63 km (1 mi; disturbance zone), 180 dB to 170 m (560 ft; cetacean
injury zone), and 190 dB to 55 m (180 ft; pinniped injury zone). The
drive pipe driving event is expected to last 1 to 3 days at each well
site (12 days maximum), although actual noise generation (pounding)
would occur only intermittently during this period.
Vertical Seismic Profiling--Data on geological strata depth
collected during initial seismic surveys at the surface can only be
inferred. However, once a well is drilled, accurate followup seismic
data can be collected by placing a receiver at known depths in the
borehole and shooting a seismic airgun at the surface near the
borehole. This data provides not only high-resolution images of the
geological layers penetrated by the borehole, but can be used to
accurately correlate (or correct) these original surface seismic data.
The procedure is known as VSP. BlueCrest proposes to conduct VSP
operations at the end of drilling each well using an array of airguns
with total volumes of between 600 and 880 cubic inches (in\3\). The
actual size of the airgun array will not be determined until the final
well depth is known. The VSP operation is expected to last less than 2
days at each well site. Illingworth & Rodkin (2014) measured noise
levels associated with VSP (using a 750 in\3\ airgun array) conducted
at Cosmopolitan State #A-1 in 2013. The results indicated that the 190
dB radius (Level A take threshold for pinnipeds) from source was 120 m
(394 ft), and the 160 dB radius (Level B disturbance take threshold)
was 2.47 km (1.54 mi).
[[Page 29895]]
Dates and Duration of Proposed Activity and Specific Geographical
Region
The request for incidental harassment authorization is for the 2016
drilling season at BlueCrest's Cosmopolitan State unit in lower Cook
Inlet. Exploratory drilling will be conducted within a 165-day
operating timeframe and completed by October 31, 2016. It is expected
that the program will take 135 days to complete.
Distribution, Abundance, and Use of Sea Otters in the Area of Specified
Activity
Based on the proposed activity area, this IHA addresses potential
impacts of BlueCrest's exploration activities on the portion of the
Southcentral Alaska stock of the northern sea otter that inhabits the
eastern shoreline of lower Cook Inlet. The Southcentral stock is
classified as ``non-strategic'' because the level of direct human-
caused mortality does not exceed the Potential Biological Removal
(PBR), and it is neither listed as ``depleted'' under MMPA, nor as
``threatened'' or ``endangered'' under the Endangered Species Act of
1973, as amended (ESA).
Sea otter populations found along the western shoreline of lower
Cook Inlet, including Kamishak Bay, are part of the Southwest Alaska
stock, which is listed as threatened under the ESA, but it is assumed
that no Southwest Alaska stock sea otters will be impacted by the
proposed project and are thus not analyzed as part of this IHA.
Based on the Service's 2014 Stock Assessment Report, the estimated
abundance of the Southcentral sea otter stock (stock being analyzed as
part of this IHA) is approximately 18,000 sea otters (USFWS 2014a).
Aerial surveys in Kachemak Bay in 2002, 2007, and 2008, indicated that
the sea otter population is increasing. The rate of increase for the
Cook Inlet portion of the population is unknown because surveys have
not been repeated; however, it is assumed to be similar to that in
Kachemak Bay between 2002 and 2014. The 2002 estimate of sea otter
population size for Cook Inlet was, therefore, adjusted to allow for
population growth at the same rate as Kachemak Bay, which predicted an
annual population growth of 495 animals and an estimated population
size of 6,904 animals for Cook Inlet (USFWS 2014b). The relative
abundance of otters in Cook Inlet is highest in the southern end of
lower Cook Inlet in Kachemak and Kamishak bays. Upper Cook Inlet does
not offer suitable habitat and is virtually devoid of sea otters. The
northern portion of lower Cook Inlet, including the project area, is
likely to have lower density of sea otters than Kachemak and Kamishak
bays, but may have periods of high seasonal use.
There are no published sea otter estimates for the specified
project area. Surveys suggest for most of the year, few sea otters
inhabit waters north of Anchor Point (Rugh et al. 2005; Larned 2006;
Gill et al. 2009; Doroff and Badajos 2010). Gill et al. (2009) did not
survey north of Anchor Point, but did find rafts of dozens of sea
otters along their transect line closest to Anchor Point during August,
but not during May or February. Doroff and Badajos (2010) tracked 44
radio-tagged sea otters for 3 years, and did not locate any sea otters
outside of Kachemak Bay other than a male that was subsistence
harvested by a Ninilchik villager (although the exact location of
harvest is unknown). During June surveys for beluga whales conducted
between 1993 and 2004, Rugh et al. (2005) recorded 2,111 sea otters in
lower Cook Inlet, but virtually none north of Anchor Point (even though
the length of the Kenai Peninsula was surveyed each year).
Recent (2013) marine mammal monitoring (for the Cosmopolitan State
exploratory drilling program) conducted 5 km (3 mi) offshore of Cape
Starichkof revealed that during August, up to 481 sea otters (median of
72 sea otters) were found riding the tides between Anchor Point and
some point well north of Cape Starichkof (Owl Ridge 2014). It is likely
that this late summer phenomenon is a result of seasonal weather
conditions that allow sea otters to safely ride the daily tides to
foraging grounds outside Kachemak Bay. Since none of the previous
surveys were conducted during the fall, it is unknown how late into
fall large numbers of sea otters are found north of Anchor Point.
Doroff and Badajos (2010) could not locate 10 of the radio-tagged sea
otters in August 2009 but these were subsequently found in September
2009. It is possible that these sea otters had moved north of Anchor
Point (outside the study area) during August, only to return to
Kachemak Bay in September.
Thus, the primary concern with sea otters is where planned
exploration activities and support activities might overlap with
seasonal sea otter use north of Anchor Point in August. Sea otter use
past October 31 is not relevant to this IHA as the activities will not
be taking place. Survey activities will be conducted in the intertidal
areas when those areas contain residual water (i.e., slack tide), and
thus the Service has determined that the onshore and intertidal
portions of BlueCrest's proposed activities will not likely interact
with, or impact, northern sea otters. Therefore, those seismic
activities and related operations are not addressed in this IHA. Sea
otters may be found within all water depths and distances from shore in
the proposed project areas. During Kenai Peninsula and Lower Cook Inlet
sea otter aerial surveys, Bodkin et al. (2003) found that sea otters
predominantly use the nearshore areas (>= 40 m; 131.2 ft) due to
increased foraging opportunities (Riedman and Estes 1990; Schneider
1976).
Biological information for the Southcentral stock of northern sea
otters can be found in the Service's Stock Assessment Report for the
Southcentral Stock of Northern Sea Otters (Service 2014) (http://www.fws.gov/alaska/fisheries/mmm/seaotters/reports.htm).
Potential Impacts of the Activities on Sea Otters
Understanding the effects of sound from oil and gas exploration on
sea otters is important for the health of sea otters and the
development of parameters by which sea otter takes can be established
and monitored. The proposed actions from BlueCrest have the potential
to disturb sea otters, particularly in protected waters in nearshore
habitats, which are used for resting, pup rearing, and foraging.
The proposed BlueCrest drilling operations that could impact local
sea otters are impulsive acoustical harassment from the brief periods
of CPD and VSP activities. Disruptions are not likely to be significant
enough to rise to the level of a take unless the sound source displaces
a sea otter from an important feeding or breeding area for a prolonged
period, and this project is unlikely to do so. The continuous
underwater noise generated by BlueCrest's proposed drilling operations
would expose diving sea otters for only a couple of minutes at most.
The airborne sound sources include rig towing, noise generated from
routine rig activities, and periodic air traffic. Routine boat traffic
noise produced by all operators will also generate airborne sound. The
Service believes that airborne sound sources will not exceed 160 dB
(Level B harassment) and will not affect sea otters (Richardson 1995).
Adherence to specified operating conditions for vessels and aircraft
will ensure that these airborne sound sources do not take sea otters.
When disturbed by noise, sea otters may respond behaviorally (e.g.,
escape response) or physiologically (e.g., increased heart rate,
hormonal response) (Harms et al. 1997; Tempel and Gutierrez 2003).
Either response results
[[Page 29896]]
in a diversion from one biological activity to another. That diversion
may cause stress (Goudie and Jones 2004), and it redirects energy away
from fitness-enhancing activities such as feeding and mating (Frid and
Dill 2002). Other changes in activities as a result of anthropogenic
noise can include increased alertness, vigilance, agonistic behavior,
escape behavior, temporary or permanent abandonment of an area,
weakened reflexes, and lowered learning responses (van Polanen Petel et
al. 2006). Chronic stress can lead to loss of immune function,
decreased body weight, impaired reproductive function, and abnormal
thyroid function.
Despite the importance of understanding the effects of sound on sea
otters, very few controlled experiments or field observations have been
conducted to address this topic. Those studies that have been conducted
conclude that sea otters are generally quite resistant to the effects
of sound, and that change to presence, distribution, or behavior
resulting from acoustic stimuli is rare (Ghoul et al. 2012a and b;
Reichmuth and Ghoul 2012; Riedman 1984). Additionally, when sea otters
have displayed behavioral disturbance to acoustic stimuli, they quickly
become habituated and resume normal activity (Ghoul et al. 2012b).
The primary potential impact of the proposed BlueCrest drilling
operations to local sea otters is from rig towing, noise generated from
routine rig activities, periodic air traffic, and impulsive acoustical
harassment from the brief periods of conductor pipe driving and VSP
activities. Although the number of individual sea otters that might be
exposed to harassment level noise represents a small portion of the
total estimated stock population, what is known about the sea otter's
behavioral responses to noise stimuli is addressed below. Disruptions
are not likely to be significant enough to rise to the level of a take
unless the sound source displaces a marine mammal from an important
feeding or breeding area for a prolonged period, and this project is
unlikely to do so.
Disturbance From Vessel Traffic and General Operations
Sea otters generally show a high degree of tolerance and
habituation to shoreline activities and vessel traffic, but disturbance
may cause animals to disperse from the local area. Populations of sea
otters in Alaska have been known to avoid areas with heavy boat traffic
but return to those same areas during seasons with less traffic
(Garshelis and Garshelis 1984). Sea otters in Alaska have shown signs
of disturbance (escape behaviors) in response to the presence and
approach of survey vessels, including: Diving and/or actively swimming
away from a boat; hauled-out sea otters entering the water; and groups
of sea otters disbanding and swimming in multiple different directions
(Udevitz et al. 1995). However, sea otters off the California coast
showed only mild interest in boats passing within hundreds of meters,
and sea otters in California appear to have habituated to boat traffic
(Riedman 1983; Curland 1997). Their behavior is suggestive of a dynamic
response to disturbance, abandoning areas when disturbed persistently
and returning when the disturbance ceased. From the above research it
is likely that some degree of disturbance from vessel traffic
associated with the proposed actions will occur. Sea otters reacting to
vessels they encounter may consume energy and divert time and attention
from biologically important behaviors, such as feeding. However, these
disturbances are expected to be short term in duration, and this
potential short-term displacement is not anticipated to affect the
overall fitness of any individual animal. We also anticipate that
individual sea otters will habituate to the presence of project vessels
and associated noise. Boat traffic, commercial and recreational, is
constant in Cook Inlet. Some sea otters in the area of activity are
likely to become habituated to vessel traffic and noise caused by
vessels due to the existing continual traffic in the area. The
additional vessel activity that will occur related to these three
projects is not expected to substantially increase vessel noise or
activity in the action area above that which is already occurring.
Sea otter collisions with vessels associated with the proposed
project are unlikely. Tugs and barges are slow moving and pose little
risk of colliding with sea otters. No fast boat use is proposed, and it
is unlikely that housing and crew transfer vessels will impact sea
otters. Vessels proposed for use to transfer housing and crew can
produce noises exceeding 190 dB when traveling at higher speeds.
However, the influence of this sound is limited to a distance of 2 to 4
m (6.6 to 13.1 ft) from the vessel. Adherence to operating conditions
will ensure that these vessels do not take sea otters.
Disturbance From Noise
Effects of noise on marine mammals are highly variable and can be
categorized as: Tolerance; masking of natural sounds; behavioral
disturbance; temporary or permanent hearing impairment; and non-
auditory effects, such as female-pup separations (Richardson et al.
1995). Whether a specific noise source will cause harm and/or
disturbance to a sea otter depends on several factors, including the
distance between the animal and the sound source, the sound intensity,
background noise levels, the noise frequency (cycles per second; hertz
(Hz) or kHz), noise duration, whether the noise is pulsed or
continuous, and whether the noise source originates in the aquatic or
terrestrial environment. For sea otters, behavioral reactions may be
shown, such as changing durations of surfacing and dives; changing
direction and/or speed; reduced/increased vocal activities; changing/
cessation of socializing or feeding; visible startle response;
avoidance of areas where noise sources are located; and/or flight
response (e.g., sea otters flushing into water from haul-outs). The
consequences of behavioral modification have the potential to be
biologically significant if the change affects growth, survival, and
reproduction.
Information regarding the northern sea otter's hearing abilities is
limited; however, the closely related southern sea otter has some
information showing this subspecies' range of hearing. Reichmuth and
Ghoul (2012) tested the aerial (from airborne sound sources) hearing
capabilities of one male southern sea otter believed to have typical
hearing. The study revealed an upper frequency hearing limit extending
to at least 32 kHz and a low-frequency limit below 0.125 kHz. These
results are generally consistent with comparable data for other
carnivores, including terrestrial mustelids. This range is also similar
to that of harbor seals (Phoca vitulina; Pinnipedia) (0.075 to 30 kHz)
(Kastak and Schusterman 1998; Hemil[auml] et al. 2006; Southall et al.
2007), which suggests pinnipeds may be a good proxy for sea otters.
Additionally, sea otters and harbor seals both exhibit amphibious
hearing and spend a considerable amount of time above water, where they
are not disturbed by airborne sound sources; southern sea otters spend
about 80 percent of their time at the sea surface, whereas harbor seals
may spend up to 60 percent of their time hauled out of the water (Frost
et al. 2001).
Riedman (1983) examined changes in the behavior, density, and
distribution of southern sea otters at Soberanes Point, California,
that were exposed to recorded noises associated with oil and gas
activity. The underwater sound sources were played at a level of 110 dB
[[Page 29897]]
and a frequency range of 50-20,000 Hz and included production platform
activity, drillship, helicopter, and semi-submersible sounds. Riedman
(1983) also observed the sea otters during seismic airgun shots fired
at decreasing distances from the nearshore environment (50, 20, 8, 3.8,
3, 1, and 0.5 nautical miles) at a firing rate of 4 shots per minute
and a maximum air volume of 4,070 cubic inches. Riedman (1983) observed
no changes in the presence, density, or behavior of sea otters as a
result of underwater sounds from recordings or airguns, even at the
closest distance of 0.5 nautical miles (<1 km). Sea otters did,
however, display slight reactions to airborne engine noise. Riedman
(1983) concluded that seismic activities had no measurable effect on
sea otter behavior. The experiment was repeated the following year
(Riedman 1984) with the same results.
In another controlled study using prerecorded sounds, Davis et al.
(1988) exposed both northern sea otters in Simpson Bay, Alaska, and
southern sea otters in Morro Bay, California, to a variety of aerial
(airborne) and underwater sounds, including a warble tone, sea otter
pup calls, killer whale calls, airhorns, and an underwater acoustic
harassment system designed to drive marine mammals away from crude oil
spills. The sounds were projected at a variety of frequencies, decibel
levels, and intervals. The authors noted that certain acoustic stimuli
could cause a startle response and result in dispersal. However, the
disturbance effects were limited in range (no responses were observed
for sea otters approximately 100-200 m (328-656 ft) from the source of
the stimuli), and habituation to the stimuli was generally very quick
(within hours or, at most, 3-4 days).
Previous work suggests that sea otters may be less responsive to
marine seismic pulses than some other marine mammals. Riedman (1983,
1984) monitored the behavior of sea otters along the California coast
while they were exposed to a single 100-in\3\ airgun and a 4,089-in\3\
airgun array. No disturbance reactions were evident when the airgun
array was as close as 0.9 km. Sea otters also did not respond
noticeably to the single airgun. Sea otters spend a great deal of time
at the surface feeding and grooming (Riedman 1983, 1984; Wolt et al.
2012). While at the surface, the potential noise exposure of sea otters
would be much reduced by pressure-release and interference (Lloyd's
mirror) effects at the surface (Greene and Richardson 1988; Richardson
et al. 1995). Finally, the average dive time of a northern sea otter
has been measured at only 85 sec (Bodkin et al. 2004) to 149 sec (Wolt
et al. 2007), thereby limiting exposure during active seismic
operations. It remains unclear whether seismic generated sound levels
even rise to the level of take at distances beyond 0.9 km, given the
animal's poor underwater hearing ability and surface behavior.
Noise thresholds have been developed by NMFS to measure injury for
pinnipeds (i.e., on temporary threshold shift (TTS) and permanent
threshold shift (PTS)). Sea otter-specific thresholds have not been
determined; however, because of their biological similarities, we
assume that noise thresholds developed by NMFS for injury for pinnipeds
will be a surrogate for sea otter impacts as well. When PTS occurs,
there is physical damage to the sound receptors in the ear. Severe
cases can result in total or partial deafness. In other cases, the
animal has an impaired ability to hear sounds in specific frequency
ranges (Kryter 1985).
The noise thresholds established by NMFS for preventing injury to
pinnipeds were developed as precautionary estimates of exposures below
which physical injury would not occur. There is no empirical evidence
that exposure to pulses of airgun sound can cause PTS in any marine
mammal, even with large arrays of airguns (Southall et al. 2007).
However, given the possibility that mammals close to an airgun array
might incur at least mild TTS in the absence of appropriate mitigation
measures, researchers have speculated about the possibility that some
individuals occurring very close to airguns might incur PTS (e.g.,
Richardson et al. 1995).
Single or occasional occurrences of mild TTS are not indicative of
permanent auditory damage, but repeated or (in some cases) single
exposures to a level well above that causing TTS onset might elicit
PTS. By means of preventing the onset of TTS, it is highly unlikely
that marine mammals could receive sounds strong enough (and over a
sufficient duration) to cause permanent hearing impairment. Until
specific sea otter thresholds are developed for both Level A and Level
B harassment and injury, the use of NMFS thresholds for pinnipeds as a
surrogate for sea otters remains the best available information. NMFS's
thresholds are further described and justified in NOAA (2005), NOAA
(2006), NOAA (2008), and Southall et al. (2007) for our analysis.
A sea otter could experience a TTS as a result of BlueCrest's
proposed operations, but there is no information on TTS impacts to sea
otters, an animal that spends much time at the surface. The average
dive time of a northern sea otter, is only 85 sec (Bodkin et al. 2004)
to 149 sec (Wolt et al. 2012). Wolt et al. (2012) found Prince William
Sound sea otters to average 8.6 dives per feeding bout. Multiplied by
the average dive time (149 sec), the average total time a sea otter
spends underwater during a feeding is about 21 min, or 12 to 18 percent
of the time of a typical 2- to 3-hour slack-tide seismic shoot. Except
for loud screams between pups and mothers (McShane et al. 1995), sea
otters do not appear to communicate vocally, either at the surface or
under water, and they do not use sound to detect prey. Thus, any TTS
due to seismic noise is unlikely to mask communication or reduce
foraging efficiency. Finally, sea otters are unlikely to rely on sound
to detect and avoid predators. For example, sea otters at the surface
are not likely to hear killer whale vocalizations.
A PTS occurs when continuous noise exposure causes hairs within the
inner ear system to die. This can occur due to moderate durations of
very loud noise levels, or long-term continuous exposure of moderate
noise levels. However, PTS is also not an issue with sea otters and
impulsive seismic noise. Sea otter exposure to underwater noises
generated by vessels (propellers) would be of very short duration
because the average dive time of a northern sea otter is only 85 sec
(Bodkin et al. 2004) to 149 sec (Wolt et al. 2012). Airborne exposure
is of little concern since pressure release and Lloyd's mirror-effect
will reduce underwater seismic noise transmitted to the air. Riedman's
(1983, 1984) observations of sea otters lack of reaction to seismic
noise was likely due largely to these transmission limits.
In conclusion, using information available for other marine mammals
as a surrogate, and taking into consideration what is known about sea
otters, the Service has set the received sound level under water of 160
dB as a threshold for Level B take by disturbance for sea otters for
this proposed IHA (Ghoul and Reichmuth 2012a and b, McShane et al.
1995, NOAA 2005, Riedman 1983, Richardson et al. 1995). Exposure to
unmitigated noise levels in the water greater than 160 dB will be
considered by the Service as potentially injurious Level B take; and
levels above 190 dB will be considered Level A take threshold for sea
otters. Level A take will not be authorized and will be avoided through
mitigation measures.
[[Page 29898]]
Seismic Operations
Air gun arrays typically produce most noise energy in the 10 to 120
Hertz (Hz) range, with some energy extending to 1,000 Hz (Richardson et
al. 1995). Sound reception studies by Ghoul and Reichmuth (2012)
determined that sea otters effectively hear between 125 Hz and 32 kHz,
or above the range where most seismic energy is produced. Thus, sea
otters appear to have limited hearing of seismic air guns (especially
compared to humans with effective hearing down to 20 Hz). To the extent
that sea otters can detect seismic noise, the potential effects of
BlueCrest's proposed activities are described below.
Masking occurs when louder noises interfere with marine mammal
vocalizations or their ability to hear natural sounds in their
environment (Richardson et al. 1995). These noise levels limit their
ability to communicate and avoid predation or other natural hazards.
However, as mentioned above, sea otters do not vocally communicate
underwater (Ghoul and Reichmuth 2012), and masking due to exposure to
underwater noise is not relevant. Sea otters do communicate above water
with the loud screams between separated mothers and pups (McShane et
al. 1995). Ghoul and Reichmuth (2012) measured these vocalizations and
found that the intensity of these calls ranged between 50 and 113 dB
Sound Pressure Level (SPL), and were loud enough that they can be heard
by humans at distances exceeding 1 km (0.62 miles) (McShane et al.
1995). Any potential masking effect from any noise entering the air
from the seismic guns would be brief (a shot) and would likely
disappear a few meters from the source.
The seismic airguns that will be used during BlueCrest's Cook Inlet
operation have the potential to acoustically injure marine mammals at
close proximity. As no sound levels have been effectively measured to
establish the threshold where injury caused by an acoustic source
exists, the 190-dB criterion for seals applies most closely to sea
otters given their more similar natural history than compared to
cetaceans.
BlueCrest intends to conduct VSP operations at the end of drilling
each well using an array of airguns with total volumes of between 600
and 880 cubic inches (in3). The VSP operation is expected to last less
than two days at each well site. Illingworth & Rodkin (2014) measured
noise levels associated with VSP (using a 750 in \3\ airgun array)
conducted at Cosmopolitan State #A-1 in 2013. The results indicated
that the 190 dB radius (Level A take threshold) from source was 120 m
(394 ft), and the 160 dB radius (Level B disturbance take threshold)
was 2.47 km (1.54 mi).
Seismic operations could also cause behavioral effects on sea
otters. For example, severe disturbance from seismic noise or
activities could cause female-pup separations, male territory
abandonment, male territory shifts and conflicts between territories,
breakup of rafts of nonbreeding males, and/or movement by individual
sea otters out of nearshore areas into deeper water. These types of
displacement events, if they occurred, could have repercussions on
breeding success and/or survival due to increased risk of predation or
other adverse conditions. However, because sea otters spend relatively
large amounts of time above the water surface compared to other marine
mammals, sea otters' potential exposure to the underwater acoustic
stimuli, such as those associated with seismic surveys (Greene and
Richardson 1988), may be lower than that of other marine mammal species
(Richardson et al. 2011). As previously stated, studies have not shown
these kinds of dramatic responses when sea otters were exposed to
seismic operations. Therefore, we have no reason to believe that sea
otters will exhibit any of these reactions during these activities.
To date, there is no evidence that serious injury, death, or
stranding of sea otters can occur from exposure to airgun pulses, even
in the case of large airgun arrays. As a result, the Service does not
expect any sea otters to incur serious injury (Level A harassment) or
mortality in Cook Inlet or strand as a result of the proposed
activities.
Drilling Operations
For BlueCrest's drilling operation, two project components have the
potential to disturb sea otters: Driving the conductor pipe at each
well prior to drilling, and VSP operations that may occur at the
completion of each well drilling. As described in BlueCrest's petition,
the CPD and VSP are impulsive noise activities. Here the Level B
disturbance exposure to sound levels greater than 160 dB applies, and
take is addressed relative to noise levels exceeding 160 dB, above
which disturbance can occur until 190 dB, after which potential injury
and Level A disturbance can occur.
Conductor Pipe Driving (CPD)
A conductor pipe is a relatively short, large-diameter pipe driven
into the sediment prior to the drilling of oil wells. Conductor pipes
are usually installed using drilling, pile driving, or a combination of
these techniques. BlueCrest proposes to drive approximately 90 m (300
ft) of 76.2-cm (30-in) conductor pipe at Cosmopolitan #2 (and any
associated delineation wells) prior to drilling using a Delmar D62-22
impact hammer. This hammer has impact weight of 6,200 kg (13,640
pounds) and reaches maximum impact energy of 224 kilonewton-m (165,215
foot-pounds) at a drop height of 3.6 m (12 ft).
Blackwell (2005) measured the noise produced by a Delmar D62-22
driving 91.4-cm (36-inch) steel pipe in Cook Inlet and found sound
pressure levels to exceed 190 dB at about 60 m (200 ft), 180 dB at
about 250 m (820 ft), and 160 dB at just less than 1.9 km (1.2 mi).
Each CPD event is expected to last 1 to 3 days, although actual noise
generation (pounding) would occur only intermittently during this
period. It is anticipated that sea otters will move away from any sound
disturbance caused by the pipe driving or become habituated.
Vertical Seismic Profiling
Once a well is drilled, accurate followup seismic data can be
collected by placing a receiver at known depths in the borehole and
shooting a seismic airgun at the surface near the borehole. This
gathered data provides not only high-resolution images of the
geological layers penetrated by the borehole, called VSP, but it can
also be used to accurately correlate (or correct) the original surface
seismic data.
BlueCrest intends to conduct VSP operations at the end of drilling
each well using an array of airguns with total volumes of between 9.83
and 14.42 liters (600 and 880 in3). Each VSP operation is expected to
last less than 1 or 2 days. Assuming a 1-m source level of 227 dB for a
14.42-liter (880-cubic-inch) array and using Collins et al.'s (2007)
transmission loss model for the Cook Inlet (18.4 Log(R)-0.00188R), the
190-dB radius (Level A take threshold for pinnipeds and surrogate for
sea otters) from source was estimated at 100 m (330 ft), and the 160-dB
radius (Level B disturbance take threshold for all sea otters) at 2.46
km (1.53 mi). These were the initial injury and safety zones
established for monitoring during a VSP operation conducted by
Buccaneer at Cosmopolitan State #1 during July 2013. Illingworth and
Rodkin (2013) measured the underwater noise levels associated with the
July 2013 VSP operation using an 11.8-liter (720 in3) array and found
the noise exceeding 160 dB extended out 2.47 km (1.56 mi) or virtually
identical to the modeled distance. The measured radius to the 190-dB
level was 75 m (246 ft). The best fit model for the empirical data was
227-19.75
[[Page 29899]]
log(R)-0.0R (Illingworth and Rodkin 2013).
Exploratory Drilling and Standard Operation
The jack-up drilling rig, Endeavour, is not expected to impact sea
otters. Lattice-legged, jack-up drill rigs are relatively quiet because
the lattice legs limit transfer of noise generated from the drilling
table to the water (Richardson et al. 1995, Spence et al. 2007).
Further, the drilling platform and other noise-generating equipment are
located above the ocean surface, so there is very little surface
contact with the water compared to drill ships and semi-submersible
drill rigs. For example, the Spartan 151, the only other jack-up
drilling rig operating in the Cook Inlet, was hydro-acoustically
measured by Marine Acoustics, Inc. (2011) while operating in 2011. The
survey results showed that continuous noise levels exceeding 120 dB
extended out only 50 m (164 ft), and that this noise was largely
associated with the diesel engines used as power generators. The
Endeavour was hydro-acoustically tested during drilling activities by
Illingworth and Rodkin (2013) in May 2013, while the rig was operating
at Cosmopolitan State #1. The results from the sound source
verification indicated that noise generated from drilling or generators
were below ambient noise. The generators used on the Endeavour are
mounted on pedestals specifically to reduce noise transfer through the
infrastructure, and they are enclosed in an insulated engine room. In
addition, the submersed deep-well pumps that cool the generators and
charge the fire-suppression system also generate noise levels exceeding
120 dB out a distance of approximately 300 m (984 ft). However, the
Service does not anticipate that this level of noise will impact sea
otters. Thus, neither actual drilling operations nor running generators
on the Endeavour drill rig generates underwater noise levels exceeding
120 dB.
For this IHA analysis, acoustical injury to sea otters can occur if
received noise levels exceed 190 dB. This is classified as a Level A
take (injury), which is not authorized by IHAs. The towing, drilling,
and pump operations to be used during BlueCrest's program do not have
the potential to acoustically injure marine mammals. Therefore, no
shutdown safety zones will be established for these activities.
However, the conductor pipe driving and VSP operations do generate
impulsive noises exceeding 190 dB. Based on the estimated distances to
the 190-dB isopleth addressed above, a 60-m (200-ft) shutdown safety
zone will be established and monitored during conductor pipe driving
(at least until the noise levels are empirically verified), while a 75-
m (246-ft) shutdown safety zone will be monitored during VSP
operations. Northern sea otters may be disturbed at noise levels
between 160 dB to 190 dB, where disturbance can occur (Level B
harassment) out to approximately 0.75 km (2.5 mi). If these takes
occur, they are likely to result in nothing more than short-term
changes in behavior.
Estimated Incidental Take of Sea Otters by Harassment
As described earlier, the Service anticipates that incidental take
will occur during Cook Inlet oil and gas activities conducted by
BlueCrest. In the sections below, we estimate take by harassment of the
numbers of sea otters from the Southcentral stock that are likely to be
affected during the proposed activities. The proposed BlueCrest
activities, previously discussed in detail, will primarily occur in a
limited area around the drilling rigs at the Cosmopolitan #A-2, #A-3,
and #B-1 sites.
The jack-up rig would be towed to the Cosmopolitan State well site
coming from either Port Graham, a travel distance of about 50 km (31
mi), or from upper Cook Inlet approximately 100 km (62 mi) north of
Cosmopolitan State (Figure 6-1, Owl Ridge 2015, page 14). After
drilling is complete, the rig will be released and moved away from the
well sites to a location of the owner's discretion. The jack-up rig
could be towed multiple times during 2016, but only the tow from Port
Graham or upper Cook Inlet to Cosmopolitan State #2, and between
Cosmopolitan State #2 and #1, are addressed in this IHA petition. It is
estimated that the longer tows (to and from the Cosmopolitan State
leases) will take 2 days to complete, while tows between Cosmopolitan
well sites will take but a few hours. The rig will be wet-towed by two
or three ocean-going tugs licensed to operate in Cook Inlet. Tugs
generate their loudest sounds while towing due to propeller cavitation.
These continuous sounds have been measured at up to 171 dB at source
(broadband), and are generally emitted at dominant frequencies of less
than 5 kHz (Miles et al. 1987, Richardson et al. 1995, Simmonds et al.
2004).
The dominant noise frequencies from propeller cavitation are
significantly less than the dominant hearing frequencies for pinnipeds
(10 to 30 kHz) and toothed whales (12 to >100 kHz), but within the
hearing range of sea otters in general (Wartzok and Ketten 1999). Also,
because it is currently unknown which tug or tugs will be used to tow
the rig, and there are few sound signatures for tugs in general, the
potential area that could be ensonified by disturbance level noise is
calculated based on an assumed 171 dB source. Using Collins et al.'s
(2007) 18.4 Log(R)-0.00188R spreading model, we determine from
hydroacoustic surveys in Cook Inlet, the distance to the 160 dB
isopleth would be at 253 meters (830 feet). Therefore, while towing,
the operating tug would ensonify a strip 0.51 km (0.31 mi) wide. The
ensonified area of the route was determined by multiplying route length
by the ensonified strip width, which equates to 253 m multiplied by 2.
Subsequently, the ZOI for the route from Port Graham to well site #B-1
is 25.3 km\2\, for the route from upper Cook Inlet to #B-1 is 50.6
km\2\, and for the route between #B-1 and #A-2 is 0.84 km\2\. Rig
movement between well site #A-2 and #A-3 is only a few meters and
represents a ZOI of 0.40 km\2\. Depending on the route of the tow, it
is expected that no more than 10 km of the entire (regardless of
direction) track will occur within the expected otter habitat (5 km
from shore) and represents a ZOI of 5.1 km\2\.
Ensonified Area--Pipe Driving
The Delmar D62-22 diesel impact hammer proposed to be used by
BlueCrest to drive the 76.2-cm (30-in) conductor pipe was previously
acoustically measured by Illingworth & Rodkin (2014) during drilling
operations at Cosmopolitan State #A-1. They found that sound exceeding
Level A noise limits for pinnipeds (and presumably for sea otters) to
extend to about 55 m (180 ft). Level B disturbance levels extended to
just less than 1.63 km (1.0 mi). The associated ZOI (area ensonified by
noise greater than 160 dB) is 8.3 km\2\ (3.1 mi\2\).
Ensonified Area--Vertical Seismic Profiling
Illingworth & Rodkin (2014) measured noise levels associated with
VSP (using a 750 in\3\ airgun array) conducted at Cosmopolitan State
#A-1 in 2013. Their results indicated that the 190 dB radius (Level A
take threshold for pinnipeds and presumably sea otters) from source was
120 m (394 ft), and the 160 dB radius (Level B disturbance take
threshold) was 2.47 km (1.54 mi). Based on these results, the
associated (160 dB) ZOI would be 19.2 km\2\ (7.4 mi\2\).
Sea Otter Densities
There are no published sea otter density estimates for the
nearshore area
[[Page 29900]]
along the Kenai Peninsula. Larned (2006) estimated from winter surveys
for Steller's eider that there were 92 sea otters (December 2004)
inhabiting the survey area--a 300-km\2\ area north of Anchor Point.
Larned (2006) also estimated that the expansion factor, or the ratio of
the full survey area to the area actually sampled, was 3.27. Applied to
the count data the estimated number of sea otters in the survey area
north of Anchor Point was 300 animals, or 1.0/km\2\. This estimate does
not take into account missed animals; either because they were
submerged or difficult to distinguish from the aerial platform
(especially pups). Evans et al. (1997) calculated a correction factor
of 2.38 for sea otters missed during aerial surveys conducted along the
Aleutian Islands. Applying this correction factor (2.38) to the
calculated density of 1.0 km\2\ increases the estimated sea otter
density to 2.38 sea otters/km\2\. A fall 2013 survey (Owl Ridge
unpublished data) of this region using line-transect methods and
program DISTANCE produced a density estimate of 2.6 sea otters/km\2\.
It is, therefore, realistic to utilize the 2.38 density estimate in
calculating estimated exposures.
Exposure Calculations
For purposes of this analysis, ``potential exposure'' was defined
as a sea otter occurring within an active ZOI of a specific noise-
generating activity. As discussed below, this potential exposure does
not necessarily constitute a Level B take, especially if the sea otter
remains above water and is not directly exposed to underwater noise.
Thus, the calculated exposure values represent the number of sea otters
that are in a position (within an active ZOI) of receiving harassment
take noise levels should they dive during the encounter.
The estimated potential exposures of sea otters by BlueCrest's
planned exploratory drilling project was determined using density
estimates derived from Larned (2006) above as adjusted for missed
animals (2.38/km\2\). Potential exposures were derived by multiplying
the maximum density (2.38 sea otters/km\2\) by the ZOI for each
activity and then by the estimated number of days the activity would
occur. The rig tow is expected to last for about 2 to 3 days, the pipe
driving about 12 days, and the VSP about 3 days. However, pipe driving
and VSP activity will occur only sporadically on any given day. The
exposure calculations can be found in Table 2.
Table 2--Estimated Number of Potential Exposures During the 2016 Drilling Period
----------------------------------------------------------------------------------------------------------------
Tow Conductor pipe VSP Total
----------------------------------------------------------------------------------------------------------------
ZOI (km\2\)..................................... 5.1 8.3 19.2 ..............
Otter Density (No./km\2\)....................... 2.38 2.38 2.38 ..............
Days............................................ NA 12 3 ..............
Potential Exposures............................. 12 238 138 388
----------------------------------------------------------------------------------------------------------------
As mentioned above, an acoustical harassment take of a sea otter
does not occur should the animal remain at the surface during the
period it is found within the ZOI. During the 2013 drilling activities
at Cosmopolitan State #1, only 52 of 356 recorded sea otters, or about
15 percent, actually dove underwater while within 260 m (853 ft) of the
drill rig (most sea otters simply drifted past, and were often asleep).
Thus, the exposure estimate of 388 found in Table 2 is conservative
because it does not take into account that most sea otters are not
expected to dive while drifting past the rig operations.
Take Authorization Request
The potential exposures for the 2016 drilling period, based on sea
otter density, is estimated to be 388 sea otters (Table 2), or about
2.1 percent of the stock. Taking into account the 15 percent of the sea
otters that are likely to dive while in the vicinity of the drill rig,
the estimated number of exposures reduces to 58, or about 0.4 percent
of the stock. However, because sea otter behavior is difficult to
predict, the more conservative 388 sea otters potentially exposed is
the requested authorization.
The Service determined that the BlueCrest activities most likely to
result in the take of sea otters, as defined under the MMPA, are CPD
and VSP. These activities will generate noise levels in the water that
may cause short-term, temporary, nonlethal, but biologically
significant changes in behavior to sea otters that the Service
considers to be Level B take by disturbance under the MMPA. Other
proposed activities, such as rig towing, noise generated from routine
rig activities, routine boat traffic, and periodic air traffic were
considered to have a limited potential for disturbance leading to Level
B take. Adherence to specified operating conditions will ensure that
take is minimized. The Service made these determinations, in part,
based on information provided in the petition materials provided by
BlueCrest, including the Marine Mammal Monitoring and Mitigation Plan
(4MP).
Potential Effects on Sea Otter Habitat
As described previously, the primary potential impacts to sea
otters are associated with high-energy impulsive sound levels. However,
other potential impacts are also possible to the surrounding habitat
from physical disturbance, discharges, or an oil spill.
Since sea otters typically inhabit nearshore marine areas,
shoreline length is a readily available metric that can be used to
quantify sea otter habitat. The total length of shoreline within the
range of the Southcentral Alaska stock of northern sea otters is
approximately 2,575 km (1,600 mi), of which 540 km (335.5 mi) are
located within Cook Inlet. Of that, the total length of shoreline for
the proposed activities is a small percentage of the total shoreline
habitat available to the Southcentral sea otter stock.
Potential Impacts to Prey
In addition to the disturbances outlined above to sea otter habitat
from noise, seismic activities could affect sea otter habitat in the
form of impacts to prey species. The primary prey species for sea
otters are sea urchins, abalone, clams, mussels, crabs, and squid
(Tinker and Estes 1999). When preferential prey are scarce, sea otters
will also eat kelp, crabs, clams, turban snails, octopuses, barnacles,
sea stars, scallops, rock oysters, fat innkeeper worms, and chitons
(Riedman and Estes 1990).
Potential Impacts From Seismic Surveys
Little research has been conducted on the effects of seismic
operations on invertebrates (Normandeau Associates, Inc. 2012).
Christian et al. (2003) concluded that there were no obvious effects
from seismic signals on crab behavior and no significant effects on the
health of adult crabs. Pearson et al. (1994) had previously found no
effects
[[Page 29901]]
of seismic signals upon crab larvae for exposures as close as 1 m (3.3
ft) from the array, or for mean sound pressure as high as 231 dB.
Invertebrates such as mussels, clams, and crabs do not have auditory
systems or swim bladders that could be affected by sound pressure.
Squid and other invertebrate species have complex statocysts (Nixon and
Young 2003) that resemble the otolith organs of fish that may allow
them to detect sounds (Budelmann 1992). Normandeau Associates, Inc.
(2012) concluded that invertebrates are sensitive to local water
movements and to low-frequency particle accelerations generated by
sources in their close vicinity. Based on these results, impulsive CPD
and VSP could acoustically impact local marine communities, but only
out to about 2 or 3 m (6 to 9 ft) at most. From an ecological community
standpoint, these impacts are considered minor.
Potential Impacts From Drill Rig Presence
The potential direct habitat impact by the BlueCrest drilling
operation is limited to the actual drill-rig footprint defined as the
area occupied and enclosed by the drill-rig legs. The jack-up rig will
temporarily disturb up to three offshore locations in upper Cook Inlet,
where the wells are proposed to be drilled. Bottom disturbance would
occur in the area where the three legs of the rig would be set down and
where the actual well would be drilled.
The Cosmopolitan State #B-1 well site is located in lower Cook
Inlet. Cook Inlet is a large subarctic estuary roughly 300 km (186 mi)
in length and averaging 96 km (60 mi) in width. It extends from the
city of Anchorage at its northern end and flows into the Gulf of Alaska
at its southernmost. For descriptive purposes, Cook Inlet is separated
into unique upper and lower sections, divided at the East and West
Forelands, where the opposing peninsulas create a natural waistline in
the length of the waterway, measuring approximately 16 km (10 mi)
across (Mulherin et al. 2001).
The potential direct habitat impact by the BlueCrest drilling
operation is limited to the actual drill-rig footprint defined as the
area occupied and enclosed by the drill rig legs. This area was
calculated as 0.22 hectares (ha) (0.54 acres) during the land use
permitting process. The collective 0.8-ha (2-ac) footprint of the well
represents a very small fraction of the 18,950-km\2\ (7,300-mi\2\) Cook
Inlet surface area. Potential damage to the Cook Inlet benthic
community will be limited, however, to the actual surface area of the
three spud cans (collective total of 442 m\2\ (4,755 ft\2\)) that form
the ``foot'' of each leg. Given the high tidal energy at the well site
locations, drilling footprints are not expected to support benthic
communities equivalent to shallow lower energy sites found in nearshore
waters. The presence of the drill rig is not expected to result in any
direct loss of sea otter habitat.
Potential Impacts From Drilling Discharges
The drill rigs will operate under an APDES general permit for
wastewater discharges. This permit authorizes discharges from oil and
gas extraction facilities engaged in exploration under the Offshore and
Coastal Subcategories of the Oil and Gas Extraction Point Source
Category (40 CFR part 435). Twelve effluents are authorized for
discharge into Cook Inlet once discharge limits set by the Alaska
Department of Environmental Conservation have been met. The authorized
discharges include drilling fluids and drill cuttings, deck drainage,
sanitary waste, domestic waste, blowout preventer fluid, boiler
blowdown, fire control system test water, uncontaminated ballast water,
bilge water, excess cement slurry, mud cuttings cement at sea floor,
and completion fluids. The drill rig will also be authorized under the
Environmental Protection Agency's (EPA's) Vessel General Permit for
deck washdown and runoff, gray water, and gray water mixed with sewage
discharges. Drilling wastes include drilling fluids, known as mud, rock
cuttings, and formation waters. Drilling wastes (non-hydrocarbon) will
be discharged to the Cook Inlet under the approved APDES general
permit.
Drilling wastes (hydrocarbon) will be delivered to an onshore
permitted location for disposal. BlueCrest will conduct an
Environmental Monitoring Study of relevant hydrographic, sediment
hydrocarbon, and heavy metal data from surveys conducted before and
during drilling mud disposal and at least 1 year after drilling
operations cease in accordance with the APDES general permit for
discharges of drilling muds and cuttings.
Non-drilling wastewater includes deck drainage, sanitary waste,
domestic waste, blowout preventer fluid, boiler blowdown, fire control
test water, bilge water, noncontact cooling water, and uncontaminated
ballast water. Non-drilling wastewater will be discharged into Cook
Inlet under the approved APDES general permit or delivered to an
onshore permitted location for disposal. Mud cuttings will be
constantly tested. Hydrocarbon-contaminated muds will be hauled
offsite. Solid waste (e.g., packaging, domestic trash) will be
classified, segregated, and labeled as general, universal, and Resource
Conservation and Recovery Act exempt or nonexempt waste. Solid waste
will be stored in containers at designated accumulation areas until it
can be packaged and transported to an approved onshore disposal
facility. Hazardous wastes should not be generated as a result of this
project. However, if any hazardous wastes are generated, they will be
temporarily stored in an onboard satellite accumulation area and then
transported offsite for disposal at an approved facility.
Discharging drill cuttings or other liquid waste streams generated
by the drilling rig--even in permitted amounts--could potentially
affect marine mammal habitat. Toxins could persist in the water column,
which could have an impact on marine mammal prey species. However,
despite a considerable amount of investment in research on exposures of
marine mammals to organochlorines or other toxins, no marine mammal
deaths in the wild can be conclusively linked to the direct exposure to
such substances (O'Shea 1999).
Drilling muds and cuttings discharged to the seafloor can lead to
localized increased turbidity and increase in background concentrations
of barium and occasionally other metals in sediments and may affect
lower trophic organisms. Drilling muds are composed primarily of
bentonite (clay), and the toxicity is, therefore, low. Heavy metals in
the mud may be absorbed by benthic organisms, but studies have shown
that heavy metals do not bio-magnify in marine food webs (Neff et al.
1989). Effects on benthic communities are nearly always restricted to a
zone within about 100 to 150 m (328 to 492 ft) of the discharge, where
cuttings accumulations are greatest. Discharges and drill cuttings
could impact fish by displacing them from the affected area. No water
quality impacts are anticipated from permitted discharges that would
negatively affect habitat for Cook Inlet sea otters.
Potential Impacts From an Oil Spill or Unpermitted Discharge
The probability of an oil spill from the proposed activities is
low. Potential sources would be a release from a vessel. An oil spill
or unpermitted discharge is an illegal act; IHAs do not authorize takes
of sea otters caused by illegal or unpermitted activities.
If an oil spill did occur, the most likely impact upon sea otters
would be mortality due to exposure to and ingestion of spilled oil.
Also,
[[Page 29902]]
contamination of sea otter habitat, their invertebrate prey, and prey
habitat would most likely result in a range of impacts ranging from
sublethal to lethal, depending on a wide variety of factors. Spill
response activities are not likely to disturb the prey items of sea
otters sufficiently to cause more than minor effects. Spill response
activities could cause sea otters to avoid contaminated habitat that is
being cleaned.
Based on the preceding discussion of potential types and likelihood
of impacts to sea otters, their prey, and habitat, the Service
anticipates that the proposed activities are not likely to cause more
than negligible, short-term, and temporary impacts to a small number of
sea otters and to a small fraction of sea otter habitat.
Potential Impacts on Subsistence Uses
The MMPA allows for Alaska Natives to harvest sea otters for
subsistence purposes or for the purposes of creating authentic Native
articles of handicrafts and clothing, provided this is accomplished in
a non-wasteful manner.
Data from the Service's Marine Mammal Marking, Tagging, and
Reporting Program (MTRP) indicates that between 1989 and 2015 (27
years), Alaska Natives harvested a total of 715 sea otters hunting from
the community of Homer, while Port Graham reported 215, Seldovia 122,
Nanwalek 39, Kenai 31, and Ninilchik 16 sea otters harvested (USFWS
MTRP unpublished data); the mean reported annual subsistence take from
2009 through 2015 from Homer, Port Graham, Seldovia, Nanwalek, Kenai,
and Ninilchik of sea otters in or near the proposed project areas was
239 animals (USFWS MTRP unpublished. data).
BlueCrest has reached out and coordinated with local communities,
including Kenai, Homer, and Ninilchik, as well as Kenai Peninsula
Borough and Cook Inlet Region, Inc. Any observed sea otter interactions
with the BlueCrest operations deemed potentially harmful will be
immediately reported to the Service by BlueCrest or their
representative.
The impact of drilling operations is unlikely to affect any sea
otter sufficient to render it unavailable for subsistence harvest in
the future. Oil spill trajectory scenarios indicate that potential
spills would travel south through the central channel of the inlet away
from shoreline subsistence harvest areas. For these reasons, we
conclude that these activities will not impact the availability of sea
otters for subsistence harvest in Cook Inlet.
Mitigation Measures
Holders of an IHA must use methods and conduct activities in a
manner that minimizes to the greatest extent practicable adverse
impacts on sea otters, their habitat, and on the availability of sea
otters for subsistence uses. Adaptive management approaches, such as
temporal or spatial limitations in response to the presence of sea
otters in a particular place or time or the occurrence of sea otters
engaged in a particularly sensitive activity (such as feeding), must be
used to avoid or minimize interactions with sea otters, and subsistence
users of these resources. BlueCrest has developed a 4MP for proposed
Cook Inlet drilling activities. This 4MP is designed to monitor and
mitigate for all marine mammals regardless of status or agency
jurisdiction. The primary concern is the harassing levels of underwater
noise produced by the drilling program operations.
Compared to non-jack-up drill rigs, the use of the jack-up drilling
rig Spartan 151 will mitigate potential noise impacts. Jack-up rigs
have less surface contact with the water and convey less noise from the
drilling table and generators into the underwater environment. Sound
source verifications conducted by MAI (2011) confirmed that underwater
drilling and generator noises produced by the Spartan 151 are near
ambient.
Shutdown safety zones will be established and monitored during pipe
driving and VSP activities. Shutdowns will be implemented to avoid
injury take to all marine mammals including sea otters.
In the unlikely event of an oil spill, BlueCrest will be working
with CISPRI, which is certified as a U.S. Coast Guard oil spill removal
organization and State of Alaska Primary Response Action Contractor
serving the Cook Inlet region of Alaska. BlueCrest will follow the
procedures as outlined in CISPRI's Technical Manual, Wildlife Tactics.
Most procedures discussed in the CISPRI Technical Manual are associated
with responses for either waterfowl or marine mammals. The CISPRI will
dedicate personnel and equipment as appropriate in support of wildlife
during a spill. The Planning Chief will work to implement a Wildlife
Plan addressing those species anticipated to be at risk and needing
protection. The protocols are described in further detail in the Oil
Discharge Prevention and Contingency Plan.
Under this Authorization, BlueCrest will be required to use the
following mitigation measures to ensure no Level A and no more than
authorized Level B takes of sea otters occur. These include conditions
for operational and support vessels, aircraft, offshore seismic
surveys, safety zones, ramp-up procedures, power down and shutdown,
emergency shutdown, Drill Rig Tows, Drive Pipe Driving, Rig Operation,
VSP Operations, and Sea Otter Observers. BlueCrest will also be
required to have sufficient and continual sound monitoring equipment to
ensure that following mitigation measures can be applied. BlueCrest's
4MP and the following mitigation measures will ensure that the numbers
of Southcentral stock of sea otters likely to be encountered during
project operations will ensure that Level B take will be minimal and
below the prescribed take allowance.
Operational and Support Vessels
Operational and support vessels must be staffed with
trained and qualified observers to alert crew of the presence of sea
otters and initiate adaptive mitigation responses.
Vessel operators must take every precaution to avoid
harassment to sea otters when a vessel is operating near these animals.
Vessels must reduce speed and maintain a distance of 100 m
(328 ft) from all sea otters when practicable.
Vessels may not be operated in such a way as to separate
members of a group of sea otters from other members of the group.
When weather conditions require, such as when visibility
drops, vessels should adjust speed accordingly to avoid the likelihood
of injury to sea otters.
All vessels must avoid areas of active or anticipated
subsistence hunting for sea otters as determined through community
consultations.
We may require a monitor on site of the activity or
onboard drillships, drill rigs, support vessels, aircraft, or vehicles
to monitor the impacts of an activity on sea otters.
Aircraft
Operators of support aircraft must, at all times, conduct
their activities at the maximum distance possible from sea otters.
Fixed-wing aircraft must operate at an altitude no lower
than 91 m (300 ft) in the vicinity of sea otters.
Rotary winged aircraft (helicopters) must operate at an
altitude no lower than 305 m (1,000 ft) in the vicinity of sea otters.
When weather conditions do not safely allow the required
minimum altitudes stipulated above, such as
[[Page 29903]]
during severe storms or when cloud cover is low, aircraft may be
operated at lower altitudes.
When aircraft are operated at altitudes below the required
minimum altitudes, the operator must avoid known sea otter locations
and should take precautions to avoid flying directly over these areas.
Aircraft routes must be planned to minimize any potential
conflict with active or anticipated sea otter subsistence hunting
activity as determined through community consultations.
Offshore Seismic Surveys
Any offshore exploration activity expected to include the
production of pulsed underwater sounds with sound source levels >=160
dB will be required to establish and monitor acoustic safety zones and
implement adaptive mitigation measures as follows:
Safety Zones
Establish and monitor with trained and qualified observers an
acoustically verified disturbance zone surrounding seismic source
arrays where the received level will be >=160 dB and an acoustically
verified safety zone surrounding seismic source arrays where the
received level will be >=190 dB.
Ramp-Up Procedures
For all seismic surveys, including airgun testing, use the
following ramp-up procedures to allow marine mammals to depart the
disturbance zone before seismic surveying begins.
Visually monitor the disturbance zone and adjacent waters
for sea otters for at least 30 minutes before initiating ramp-up
procedures. If no sea otters are detected, you may initiate ramp-up
procedures. Do not initiate ramp-up procedures at night or when you
cannot visually monitor the disturbance zone for marine mammals.
Initiate ramp-up procedures by firing a single airgun. The
preferred airgun to begin with should be the smallest airgun, in terms
of energy output (dB) and volume (cubic inches).
Continue Ramp-up by gradually activating additional
airguns over a period of at least 20 minutes, but no longer than 40
minutes, until the desired operating level of the airgun array is
obtained.
Powerdown and Shutdown
Immediately power down or shutdown the seismic source array and/or
other acoustic sources whenever one or more sea otters are sighted
close to or within the area delineated by the 190 dB disturbance zone.
If the power down operation cannot reduce the received sound pressure
level to 160 dB or less, the operator must immediately shut down the
seismic airgun array and/or other acoustic sources.
Emergency Shutdown
If observations are made or credible reports are received that one
or more sea otters are within the area of the seismic survey and are
indicating acute distress, such as any injury due to seismic noise, the
seismic airgun array will be immediately shutdown and the Service
contacted. The airgun array will not be restarted until review and
approval by the Service.
Drill Rig Tow
Because the ocean tugs will be under tow while they are generating
noises of concern they will be traveling at very slow speeds (1 to 5
knots), providing sufficient time for marine mammals to move from the
vicinity and avoid any possible injury take due to collision or noises
exceeding injury thresholds. Altering courses or speeds to avoid
harassment takes will be conducted when feasible, but completely
shutting engines down would represent a major (and perhaps illegal)
safety concern given the inherent hazards of towing at sea. Thus, while
marine mammals will be monitored, no safety shutdowns will occur;
however, marine mammal monitoring will occur during all tow events.
Drive Pipe Driving
Soon after the drill rig is positioned on the well head, the
conductor pipe will be driven as the first stage of the drilling
operation. At least two marine mammal observers (one operating at a
time) will be stationed aboard the rig during this 2 to 3 day operation
monitoring a 1.6-km (1-mi) shutdown safety zone. The impact hammer
operator will be notified to shutdown hammering operations at the
approach of a marine mammal to the safety zone. Also, a ramp up of the
hammering will begin at the start of each hammering session. The ramp
up procedure involves initially starting with three soft strikes, 30
seconds apart. This delayed-strike start alerts marine mammals of the
pending hammering activity and provides them time to vacate the area.
Monitoring will occur during all hammering sessions.
Rig Operation
Hydroacoustic tests were conducted by MAI (2011) on the Spartan 151
in 2011. The results indicated that the lattice legs of the drill rig
were preventing significant noise from entering the water column. The
MAI (2011) found that underwater noise levels associated with drilling
did not exceed ambient, while the large power generators onboard the
rig produced noise that exceeded 120 dB only out about 50 m. Noise
associated with drilling and general operation of the drill rig is of
little concern to marine mammals.
VSP Operations
As with the CPD, marine mammal observers will be redeployed during
the VSP operations to monitor a shutdown safety zone. Illingworth &
Rodkin (2014) measured noise levels during VSP operations associated
with BlueCrest post-drilling operations at the Cosmopolitan State #B-1
site during July 2013. The results indicated that the 720-in\3\ airgun
array used during the operation produced noise levels exceeding 160 dB
out to a distance of approximately 2.47 km (1.54 mi). Thus, all VSP
monitoring will involve a 2.5-km (1.55-mi) shutdown zone. The airgun
operator will be notified to shut down firing of the guns at the
approach of a marine mammal to the safety zone. Also, a ``soft start''
ramp up of the guns will begin at the start of each airgun session.
Sea Otter Observers
The initial rig tow from Port Graham to Cosmopolitan #B-1 is
expected to last less than 12 hours. A single observer will monitor for
sea otters during the tow. If the rig is towed from an upper Cook Inlet
location, and is expected to last more than 12 hours (which it is),
then two observers, working alternate shifts, will be used.
Pipe driving is expected to take 2 to 3 days to complete. Two sea
otter observers, working alternate shifts, will be stationed aboard the
drill rig during all pipe driving activities at the well. The observers
will operate from a station as close to the well head as safely
possible.
As with the pipe driving, two observers will monitor all VSP
activities. Monitoring during zero-offset VSP will be conducted by two
sea otter observers operating from the drill rig. During walk-away VSP
operations, an additional two sea otter observers will monitor from the
seismic source vessel.
Only trained sea otter observers will be used during this project.
All observers will either have previous experience monitoring for sea
otters, or will go through a sea otter (marine mammal) monitoring
training course. Less-experienced observers will be paired with
veterans. Observers will
[[Page 29904]]
also be provided with field guides, instructional handbooks, and a
contacts list to assist in assuring data are collected effectively and
accurately.
Notification of Injured or Dead Sea Otter
In the unexpected event that the specified activity clearly causes
the take of a sea otter in a manner not authorized by the IHA (if
issued), such as a serious injury or mortality (e.g., ship-strike),
BlueCrest would immediately report the incident to the Service. The
report would include the following information:
Time, date, and location (latitude/longitude) of the
incident;
Name and type of vessel involved;
Vessel's speed during and leading up to the incident;
Description of the incident;
Status of all sound source use in the 24 hours preceding
the incident;
Water depth;
Environmental conditions (e.g., wind speed and direction,
cloud cover, and visibility);
Description of all sea otter observations in the 24 hours
preceding the incident;
Species identification or description of the animal(s)
involved;
Fate of the animal(s); and
Photographs or video footage of the animal(s) (if
equipment is available).
In the event that BlueCrest discovers an injured or dead sea otter,
and the lead PSO 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, or scavenger damage), BlueCrest would report the
incident to the Service within 24 hours of the discovery. BlueCrest
would provide photographs or video footage (if available) or other
documentation of the stranded animal sighting to NMFS, FWS, and the
Marine Mammal Stranding Network.
Maintaining Safe Radii
Acoustical injury to sea otters can occur if received noise levels
exceed 190 dB. BlueCrest is not requesting authorization of these
takes, termed Level A injury takes, but instead will implement
mitigation measures to avoid these takes, including shutdown safety
zones. However, the rig towing procedures to be used during BlueCrest's
operation do not have the potential to acoustically injure sea otters.
Therefore, no shutdown safety zones will be established for this
activity. The pipe driving and VSP operations do generate impulsive
noises exceeding 190 dB. Based on the estimated distances to the 190 dB
isopleth addressed above, a 170-m (560-ft) shutdown safety zone will be
established and monitored during pipe driving, while a 240-m (787-ft)
shutdown safety zone will be monitored during VSP operations. These
safety zones are conservative for sea otters given that injury take is
not expected until noise levels reach 190 dB.
Monitoring and Reporting Requirements
We require holders of an IHA to cooperate with the Service and
other designated Federal, State, and local agencies to monitor the
impacts of oil and gas exploration activities on sea otters. In this
case, BlueCrest coordinated with NMFS, Bureau of Safety and
Environmental Enforcement, and the Army Corps of Engineers. BlueCrest
reached out to the communities of Homer, Port Graham, Kenai, Seldovia,
Soldotna, and Ninilchik, as well as Kenai Peninsula Borough, Cook Inlet
Region, Inc., Cook Inlet Keeper, United Cook Inlet Drift Association,
and the Chugach Alaska Services.
BlueCrest must submit a final report to the Service within 90 days
after the end of the project. The report must describe the operations
that were conducted and the marine mammals that were observed. The
report must include documentation of methods, results, and
interpretation pertaining to all monitoring. The 90-day report must
summarize the dates and locations of seismic operations, and all sea
otter sightings (dates, times, locations, activities, associated
seismic survey activities, sea otter behavior, and any observed
behavioral changes). All observations of sea otters, including any
observed reactions to the seismic operations, will be recorded and
reported to the Service.
Monitoring Requirements
Holders of an IHA will be required to:
Maintain trained and qualified onsite observers to carry
out monitoring programs for sea otters necessary for initiating
adaptive mitigation responses.
Place trained and qualified observers on board all
operational and support vessels to alert crew of the presence of sea
otters to initiate adaptive mitigation responses and to carry out
specified monitoring activities identified in the monitoring and
mitigation plan necessary to evaluate the impact of authorized
activities on sea otters and the subsistence use of sea otters.
Cooperate with the Service and other designated Federal,
State, and local agencies to monitor the impacts of oil and gas
exploration activities on sea otters.
The wet-tow will most likely occur during the summer when Alaska
days are long. However, because there are no injury-take concerns with
the wet-tows, and only a very low potential for acoustical harassment,
no special considerations will be made to monitor during poor
visibility conditions. The CPD and VSP activities will be limited to
daylight hours, and when sea conditions are light, therefore, when
marine mammal observation conditions will be generally good.
Standard marine mammal observing field equipment will be used
including reticule binoculars (10 x 42), big-eye binoculars (30x),
inclinometers, and range-finders. Because rig-towing, CPD, and VSP will
be limited to daylight hours, no special equipment such as night scopes
or FLIRS (forward looking infra-red thermal imagery system) will be
needed.
All location, weather, and marine mammal observation data will be
recorded onto a standard field form. Global positioning system and
weather data will be collected at the beginning and end of a marine
mammal monitoring period and at every half-hour in between. Position
data will also be recorded at the change of an observer or the sighting
of a marine mammal. Enough position data will be collected to
eventually map an accurate charting of any vessel travel. Recorded
marine mammal data will also include species, group size, behavior, and
any apparent reactions to the project activities. Any behavior that
could be construed as a take will also be recorded in the notes.
Reporting Requirements
Holders of an IHA must keep the Service informed on the progress of
authorized activities by:
Notifying the Service at least 48 hours prior to the onset
of activities.
Providing weekly progress reports of authorized
activities, noting any significant changes in operating state and or
location.
Notifying the Service within 48 hours of ending activity.
Weekly Observation Reports
Holders of an IHA must report, on a weekly basis, observations of
sea otters during project activities. Information within the
observation report will include, but is not limited to:
Date, time, and location of each sighting.
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Number, sex, and age (if determinable).
Observer name, company name, vessel name or aircraft
number, letter of authorization number, and contact information.
Weather, visibility, and sea conditions at the time of
observation.
Estimated distance from the animal or group when initially
sighted, at closest approach, and end of the encounter.
Industry activity at time of sighting and throughout the
encounter. If a seismic survey, record the estimated ensonification
zone where animals are observed.
Behavior of animals at initial sighting, any change in
behavior during the observation period, and distance from Industry
activity associated with those behavioral changes.
Detailed description of the encounter.
Duration of the encounter.
Duration of any behavioral response (e.g., diving,
swimming, splashing, etc.).
Mitigation actions taken.
Activity reports will be submitted to the Service within 72 hours
of completing each of the three activities (rig tow, pipe driving, and
VSP).
Monthly Observation Reports
The monthly report will contain and summarize the following
information pertaining to sea otters as appropriate:
Dates, times, locations, heading, speed, weather, sea
conditions (including Beaufort Sea state and wind force), and
associated activities during all seismic operations and marine mammal
sightings.
Species, number, location, distance from the vessel, and
behavior of any sighted marine mammals, as well as associated seismic
activity (number of power-downs and shutdowns), observed throughout all
monitoring activities.
A description of the implementation and effectiveness of
the mitigation measures of the IHA.
After-Action Monitoring Reports
The results of monitoring efforts identified in the 4MP must be
submitted to the Service for review within 90 days of the expiration
date of the IHA.
The report must include, but is not limited to, the following
information:
A summary of monitoring effort including: Total hours,
areas/distances, and distribution of sea otters through the project
area of each rig, vessel, and aircraft.
Analysis of factors affecting the visibility and
detectability of sea otters by specified monitoring.
Analysis of the distribution, abundance, and behavior of
sea otter sightings in relation to date, location, sea conditions, and
operational state.
Estimates of take based on the number of animals
encountered/km of vessel and aircraft operations by behavioral response
(no response, moved away, dove, etc.), and animals encountered per day
by behavioral response for stationary drilling operations.
Raw data in electronic format (i.e., Excel spreadsheet) as
specified by the Service in consultation with Industry representatives.
Sighting rates of sea otters during periods with and
without airgun activities (and other variables that could affect
detectability).
Initial sighting distances versus airgun activity state
(firing, powered down, or shut-down).
Closest point of approach versus airgun activity state.
Observed behaviors and types of movements versus airgun
activity state.
Numbers of sightings/individuals seen versus airgun
activity state.
Findings
The Service proposes the following findings regarding this action:
Small Numbers Determination and Estimated Take by Incidental Harassment
For small take analysis, the statute and legislative history do not
expressly require a specific type of numerical analysis, leaving the
determination of ``small'' to the agency's discretion. Factors
considered in our small numbers determination include the following:
(1) The number of northern sea otters inhabiting the proposed
impact area is small relative to the size of the northern sea otter
population. The potential exposures for the 2016 drilling period, based
on otter density, is estimated to be 388 sea otters, or about 2.1
percent of the stock. Taking into account that 15 percent of the sea
otters are likely to dive while in the vicinity of the drill rig, the
estimated number of exposures reduces to 58. However, because sea otter
behavior is difficult to predict, the more conservative 388 sea otters
potentially exposed is the requested authorization. This is
approximately 2 percent of the estimated population size of 18,297
(USFWS 2014).
(2) The area where the proposed activities would occur is a
relatively small fraction of the available habitat of the Southcentral
Alaska stock of northern sea otters. Since sea otters typically inhabit
nearshore marine areas, shoreline length is a readily available metric
that can be used to quantify sea otter habitat. The total length of
shoreline within the range of the Southcentral Alaska stock of northern
sea otters is approximately 2,575 km (1,600 mi), of which 540 km (335.5
mi) are located within Cook Inlet. Of that, the total length of
shoreline for the proposed activities is approximately 60 km (37.3 mi),
which is a small percentage of the total shoreline habitat available to
the Southcentral sea otter stock. Any potential impacts to prey caused
by the proposed activities would occur in the limited area of the
shoreline habitat.
(3) Monitoring requirements and mitigation measures are expected to
limit the number of incidental takes. Level A harassment (harassment
that has the potential to injure sea otters) is not authorized. If a
sea otter was observed within or approaching the 190 dB exposure area
of the various gun arrays, avoidance measures would be taken, such as
decreasing the speed of the vessel and/or implementing a power down or
shutdown of the airguns. Power-up and ramp-up procedures would prevent
Level A harassment and limit the number of incidental takes by Level B
harassment by affording time for sea otters to leave the area.
Monitoring and mitigation measures are thus expected to prevent any
Level A harassment and to minimize Level B harassment. Further,
monitoring and reporting of sea otter activity in proximity to
activities will allow the Service to reanalyze and possibly refine and
adjust future take estimates as exploration activities continue in sea
otter habitat into the future.
The mitigation measures outlined above are intended to minimize the
number of sea otters that may be disturbed by the proposed activity.
Any impacts on individuals are expected to be limited to Level B
harassment and to be of short-term duration. No take by injury or death
is anticipated or authorized. Should the Service determine, based on
the monitoring and reporting to be conducted throughout the survey
activities, that the effects are greater than anticipated, the
authorization may be modified, suspended, or revoked.
Negligible Impact
The Service finds that any incidental ``take by harassment'' that
may result from this proposed seismic survey 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, and would, therefore, have no more than a negligible impact
on the stock. In making this finding, we considered the
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best available scientific information, including: (1) The biological
and behavioral characteristics of the species; (2) the most recent
information on distribution and abundance of sea otters within the area
of the proposed activity; (3) the potential sources of short-term
disturbance during the proposed activity; and (4) the potential
response of sea otters to this short-term disturbance. In addition, we
conducted a thorough review of material supplied by the applicants,
information from other operators in Cook Inlet, our files and datasets,
data acquired from NMFS, and published reference materials. We also
consulted with other sea otter experts in the Cook Inlet area,
including the Service and NMFS researchers and local residents.
Limited evidence (Riedman 1983, 1984) suggests that sea otters are
not particularly sensitive to or adversely affected by sound. Responses
of sea otters to disturbance would most likely be diving and/or
swimming away from the sound source, which may entail the temporary,
but not sustained, interruption of foraging, breeding, resting, or
other natural behaviors. Thus, although 388 sea otters (around 2
percent of the population) are estimated to be potentially taken (i.e.,
potentially disturbed) by Level B harassment by means of exposure to
sound levels of 160 dB or greater but less than 190 dB for the duration
of the project, we do not expect that this type of harassment would
result in adverse effects on the species or stock through effects on
annual rates of recruitment or survival.
Our finding of negligible impact applies to incidental take
associated with the proposed activities as mitigated through this
authorization process. This authorization establishes monitoring and
reporting requirements to evaluate the potential impacts of the
proposed activities, as well as mitigation measures designed to
minimize interactions with, and impacts to, sea otters.
Impact on Subsistence
We find that the anticipated harassment caused by the proposed
activities would not have an unmitigable adverse impact on the
availability of sea otters for taking for subsistence uses. In making
this finding, we considered the timing and location of the proposed
activities and the timing and location of subsistence harvest
activities and patterns, as reported through the MTRP, in the proposed
project area, as well as the applicants' consultation with potentially
affected subsistence communities. More information can be found on our
Web site at http://www.fws.gov/alaska/fisheries/mmm/iha.htm.
The Service finds that the proposed activities will have a
negligible impact on small numbers of sea otters in Southcentral Alaska
and will not have an unmitigable adverse impact on the availability of
the stock for subsistence uses. Further, we have prescribed permissible
methods of take, means to have the least practicable impact on the
stock and its habitat, and monitoring requirements.
Required Determinations
National Environmental Policy Act (NEPA)
We have prepared a draft Environmental Assessment (EA) (see Public
Comments above) in accordance with the NEPA (42 U.S.C. 4321 et seq.).
We have preliminarily concluded that approval and issuance of this
authorization for the nonlethal, incidental, unintentional take by
Level B harassment of small numbers of northern sea otters in the
Southcentral Alaska stock during oil and gas industry exploration
activities in the lower Cook Inlet of Alaska would not significantly
affect the quality of the human environment, and that the preparation
of Environmental Impact Statements on these actions is not required by
section 102(2) of the NEPA or its implementing regulations.
Endangered Species Act
Oil and gas exploration in U.S. waters is authorized by The Bureau
of Ocean Energy Management, Regulation and Enforcement. All Federal
agencies are required to ensure the actions they authorize are not
likely to jeopardize the continued existence of any threatened or
endangered species or result in destruction or adverse modification of
critical habitat. The proposed oil and gas activities will occur
entirely within the range of the Southcentral Alaska stock of the
northern sea otter, which is not listed as threatened or endangered
under the ESA. Though it is not a focal species subject to the issuance
of this IHA, it is worth noting that the federally listed threatened
Steller's eiders (Polysticta stelleri) have molting and wintering range
that includes the Cook Inlet. However, during the time period of the
proposed project, it is highly unlikely that any Steller's eider will
be present in the action area. Additionally, even in the unlikely event
that a Steller's eider is present; the issuance of an IHA for
BlueCrest's proposed seismic surveys will not have any impact on the
species. Thus, the Service's proposed issuance of an IHA will have no
effect on Steller's eiders and no additional ESA consultation will be
necessary.
Government-to-Government Relations With Native American Tribal
Governments
In accordance with the President's memorandum of April 29, 1994,
``Government to Government Relations with Native American Tribal
Governments'' (59 FR 22951), Executive Order 13175, Department of the
Interior Secretarial Order 3225 of January 19, 2001 (Endangered Species
Act and Subsistence Uses in Alaska (Supplement to Secretarial Order
3206)), Department of the Interior Secretarial Order 3317 of December
1, 2011 (Tribal Consultation and Policy), Department of the Interior
Memorandum of January 18, 2001 (Alaska Government-to-Government
Policy), the Department of the Interior's manual at 512 DM 2, and the
Native American Policy of the U.S. Fish and Wildlife Service, January
20, 2016, we readily acknowledge our responsibility to communicate and
work directly on a Government-to-Government basis with federally
recognized Alaska Natives Tribes in developing programs for healthy
ecosystems, to seek their full and meaningful participation in
evaluating and addressing conservation concerns for listed species, to
remain sensitive to Alaska Native culture, and to make information
available to Alaska Natives.
Furthermore, and in accordance with Department of the Interior
Policy on Consultation with Alaska Native Claims Settlement Act of 1971
(ANCSA) Corporations, August 10, 2012, we likewise acknowledge our
responsibility to communicate and work directly with ANCSA Corporations
in evaluating and addressing conservation concerns for listed species,
to remain sensitive to Alaska Native culture, and to make information
available to ANSCA Corporations. We have evaluated possible effects on
federally recognized Alaska Native Tribes. Through the IHA process
identified in the MMPA, Industry presents a communication process,
culminating in a Plan of Cooperation (POC), if warranted, with the
Native communities most likely to be affected and engages these
communities in numerous informational meetings.
Through various interactions and partnerships, we have determined
that the issuance of this IHA is appropriate. We are open to discussing
ways to continually improve our coordination and information exchange,
including through the IHA/POC process, as may be requested by Tribes or
other Native groups.
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Proposed Authorization
The Service proposes to issue BlueCrest an IHA for the nonlethal,
incidental, unintentional take by Level B harassment of small numbers
of northern sea otters (Enhydra lutris kenyoni) in the Southcentral
Alaska stock during industry exploration activities in the lower Cook
Inlet of Alaska, as described in this document and in their petition.
We neither anticipate nor propose authorization for take by injury or
death. The final IHA would be effective immediately after the date of
issuance through October 31, 2016.
The final IHA will also incorporate the mitigation, monitoring, and
reporting requirements described in this proposal. The applicant will
be expected and required to implement and fully comply with those
requirements. The IHA will not authorize the intentional take of
northern sea otters, nor take by injury or death.
If the nature or level of activity changes or exceeds that
described in this proposal and in the IHA petition, or the nature or
level of take exceeds that projected in this proposal, the Service will
reevaluate its findings. The Secretary may modify, suspend, or revoke
this authorization if the findings are not accurate or the mitigation,
monitoring, and reporting requirements described herein are not being
met.
Karen P. Clark,
Acting Regional Director, Alaska Region.
[FR Doc. 2016-11426 Filed 5-12-16; 8:45 am]
BILLING CODE 4333-55-P