Marine Mammals; Incidental Take During Specified Activities: Cook Inlet, Alaska
| Published date | 01 August 2019 |
| Citation | 84 FR 37716 |
| Record Number | 2019-16279 |
| Section | Rules and Regulations |
| Court | Fish And Wildlife Service |
Federal Register, Volume 84 Issue 148 (Thursday, August 1, 2019)
[Federal Register Volume 84, Number 148 (Thursday, August 1, 2019)]
[Rules and Regulations]
[Pages 37716-37750]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2019-16279]
[[Page 37715]]
Vol. 84
Thursday,
No. 148
August 1, 2019
Part II Department of the Interior----------------------------------------------------------------------- Fish and Wildlife Service50 CFR Part 18----------------------------------------------------------------------- Marine Mammals; Incidental Take During Specified Activities: Cook
Inlet, Alaska; Final Rule
Federal Register / Vol. 84 , No. 148 / Thursday, August 1, 2019 /
Rules and Regulations
[[Page 37716]]
-----------------------------------------------------------------------
DEPARTMENT OF THE INTERIOR
Fish and Wildlife Service
50 CFR Part 18
[Docket No. FWS-R7-ES-2019-0012; FXES111607MRG01-190-FF07CAMM00]
RIN 1018-BD63
Marine Mammals; Incidental Take During Specified Activities: Cook
Inlet, Alaska
AGENCY: Fish and Wildlife Service, Interior.
ACTION: Final rule.
-----------------------------------------------------------------------
SUMMARY: We, the U.S. Fish and Wildlife Service, in response to a
request from Hilcorp Alaska, LLC, Harvest Alaska, LLC, and the Alaska
Gasline Development Corporation, finalize regulations authorizing the
nonlethal, incidental take by harassment of small numbers of northern
sea otters in State and Federal waters (Alaska and the Outer
Continental Shelf) within Cook Inlet, Alaska, as well as all adjacent
rivers, estuaries, and coastal lands. Take may result from oil and gas
exploration, development, production, and transportation activities
occurring for a period of 5 years. This rule authorizes take by
harassment only; no lethal take is authorized. We will issue Letters of
Authorization, upon request, for specific proposed activities in
accordance with these regulations. Additionally, the Office of
Management and Budget has approved a revision of the existing
Information Collection control number 1018-0070, for incidental take of
marine mammals in the Beaufort and Chukchi Seas, to include oil and gas
activities in Cook Inlet.
DATES: This rule is effective August 1, 2019, and remains effective
through August 1, 2024.
ADDRESSES: Document availability: You may view this rule, the original
and updated application packages, supporting information, final
environmental assessment and U.S. Fish and Wildlife Service finding of
no significant impact (FONSI), and the list of references cited herein
at http://www.regulations.gov under Docket No. FWS-R7-ES-2019-0012, or
these documents may be requested as described under FOR FURTHER
INFORMATION CONTACT.
FOR FURTHER INFORMATION CONTACT: Mr. Christopher Putnam, U.S. Fish and
Wildlife Service, MS 341, 1011 East Tudor Road, Anchorage, Alaska
99503, by email at [email protected], or by telephone at 1-
800-362-5148. Persons who use a telecommunications device for the deaf
(TDD) may call the Federal Relay Service (FRS) at 1-800-877-8339, 24
hours a day, 7 days a week.
For information on Information Collection control number 1018-0070,
contact the Service Information Collection Clearance Officer, U.S. Fish
and Wildlife Service, MS: BPHC, 5275 Leesburg Pike, Falls Church, VA
22041-3803 (mail); 703-358-2503 (telephone), or [email protected]
(email). Please include ``1018-0070'' in the subject line of your email
request.
SUPPLEMENTARY INFORMATION:
Immediate Promulgation
In accordance with 5 U.S.C. 553(d)(3), we find that we have good
cause to make this rule effective less than 30 days after publication.
Immediate promulgation of the rule will ensure that the applicant will
implement mitigation measures and monitoring programs in the geographic
region that reduce the risk of any lethal and nonlethal effects to sea
otters by their activities.
Background
Section 101(a)(5)(A) of the Marine Mammal Protection Act of 1972
(16 U.S.C. 1361(a)(5)(A)) (MMPA), gives the Secretary of the Interior
(Secretary) the authority to allow the incidental, but not intentional,
taking of small numbers of marine mammals in response to requests by
U.S. citizens engaged in a specified activity in a specified region.
The Secretary has delegated authority for implementation of the MMPA to
the U.S. Fish and Wildlife Service (Service). According to the MMPA,
the Service shall allow this incidental taking for a period of up to 5
years if we make findings that such taking: (1) Will affect only small
numbers of individuals of these species or stocks; (2) will have no
more than a negligible impact on these species or stocks; (3) will not
have an unmitigable adverse impact on the availability of these species
or stocks for taking for subsistence use by Alaska Natives; and (4) we
issue an incidental take regulation (ITR) setting forth: (a) The
permissible methods of taking, (b) the means of effecting the least
practicable adverse impact on the species, their habitat, and the
availability of the species for subsistence uses, and (c) the
requirements for monitoring and reporting. If final regulations
allowing such incidental taking are issued, we may then subsequently
issue a letter of authorization (LOA), upon request, to authorize
incidental take during the specified activities.
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 (16 U.S.C. 1362(13)). Harassment, as defined by the MMPA
for non-military readiness activities, means any act of pursuit,
torment, or annoyance that (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 ``negligible impact,'' ``small numbers,'' ``unmitigable
adverse impact,'' and ``U.S. citizens,'' among others, are defined in
title 50 of the Code of Federal Regulations at 50 CFR 18.27, the
Service's regulations governing take of small numbers of marine mammals
incidental to specified activities. ``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. ``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 stock.
``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 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. The term ``least practicable adverse
impact'' is not defined in the MMPA or its enacting regulations. We
ensure the least practicable adverse impact by
[[Page 37717]]
requiring mitigation measures that are effective in reducing the
impacts of the proposed activities, but are not so restrictive as to
make conducting the activities unduly burdensome or impossible to
undertake and complete.
Implementation of the ITR will require information collection
activities. The Office of Management and Budget has approved a revision
of the existing Information Collection control number 1018-0070, for
incidental take of marine mammals in the Beaufort and Chukchi Seas, to
include oil and gas activities in Cook Inlet.
Summary of Request
On May 3, 2018, Hilcorp Alaska, LLC (Hilcorp), Harvest Alaska, LLC
(Harvest), and the Alaska Gasline Development Corporation (AGDC),
hereinafter referred to as the ``applicant,'' petitioned the Service to
promulgate regulations pursuant to section 101(a)(5)(A) of the MMPA for
the nonlethal, unintentional taking of small numbers of northern sea
otters (Enhydra lutris kenyoni; hereafter ``sea otters'' or ``otters,''
unless otherwise indicated) incidental to oil and gas exploration,
development, production, and transportation activities in Cook Inlet,
Alaska, for a period of 5 years. On June 28, 2018, the applicant
submitted an amended request providing additional project details. In
March 2019, Hilcorp and Harvest notified the Service that three-
dimensional (3D) seismic survey activities originally planned to begin
in April 2019 would be delayed until fall 2019. In June 2019, AGDC,
Hilcorp, and Harvest also provided an updated application package at
the request of the Service. The updated application clarified project
details and provided additional information where necessary to respond
to questions and concerns raised by comments received during the public
review of the proposed ITR. These updates and clarifications were minor
and did not significantly change the analysis of effects or the
estimates of take, and did not alter the conclusions regarding whether
the planned activities would have a negligible impact on the stocks,
would affect subsistence use, or would affect more than a small number
of animals.
Summary of Changes From the Proposed ITR
In preparing this final regulation for the incidental take of sea
otters, we reviewed and considered comments and information from the
public on our proposed rule published in the Federal Register on March
19, 2019 (84 FR 10224), for which the comment period was extended by
notice in the Federal Register on April 5, 2019 (84 FR 13603). We also
reviewed and considered comments and information from the public for
our draft Environmental Assessment (EA). Based on those considerations,
and the new information provided by the applicant, we are finalizing
these regulations with the following changes from our proposed rule:
Table 1 and table 3 were updated to reflect the most
recent project details available from the applicant.
The Description of Specified Activities and table 1 were
appended to include redevelopment of existing wells at Granite Point.
Mitigation measures were added or modified in Sec.
18.137(b)(1)(ii), (b)(4)(ii), (b)(7)(ii), (b)(9), (c)(2), (c)(3),
(e)(4), and Sec. 18.140(b) of this final rule.
The total estimated number of Level B takes was adjusted
from 1,663 to 1,684 after the analysis was updated to reflect updates
in the project plans.
The duration of activities used in the estimation of take
was adjusted to reflect the maximum number of days during which
underwater work may generate noise above thresholds for take. The
following adjustments were made: Vibratory sheet pile driving was
adjusted from 5 to 20 days, Lower Cook Inlet (LCI) pipe driving was
revised from 3 to 12 days, Trading Bay (TB) pipe driving was revised
from 1.5 to 6 days, vertical seismic profiling (VSP) in LCI was changed
from 2 to 8 days, VSP in TB was adjusted from 1 to 4 days, and use of
water jets was increased from 10.5 to 21 days.
The analyses of take tables were updated to remove tugs
towing rigs and use of hydraulic grinders at the request of the
applicant and after analysis of take using the updated duration for
these sources indicated that take was unlikely.
Field verifications of sound production during two-
dimensional (2D) and 3D seismic surveys have been added to the required
mitigation measures.
A discussion of the alternative mitigation measures
evaluated but not required has been added.
Use of a mitigation gun was changed from required
mitigation for 2D and 3D seismic surveys to a measure that may be
required in LOAs issued under this ITR.
Table 9 was added to clarify allocation of sea otter take
by location of activity relative to the appropriate stock boundary.
Total estimated Level A take was adjusted from three takes
from the southcentral Alaska stock to one take from the southwest
Alaska stock and two takes from the southcentral Alaska stock. This
change was made to correct an error in the proposed ITR.
A mitigation measure was added requiring an applicant for
an LOA to evaluate alternatives to pile-supported facilities and
establishing that the Service may require sound-attenuation devices or
alternatives to pile-supported designs.
The Estimated Incidental Take section was updated to
reflect changes to the analysis due to the updated project details and
to provide additional clarity in the analysis methods used.
The evaluation of impacts of the specified activities was
modified throughout the document to focus on the total numbers of takes
rather than the numbers of individual sea otters taken. This change was
needed to ensure the estimates from the analysis were accurate and did
not underestimate take.
Description of the Regulation
This regulation does not authorize the specified activities to be
conducted by the applicant. Rather, it authorizes the nonlethal
incidental, unintentional take of small numbers of sea otters
associated with those planned activities based on standards set forth
in the MMPA. The ITR includes: Permissible amounts and methods of
nonlethal taking; measures to ensure the least practicable adverse
impact on sea otters and their habitat; measures to avoid and reduce
impacts to subsistence uses; and requirements for monitoring and
reporting.
Description of the ITR Geographic Area
The geographic region of the ITR encompasses Cook Inlet, Alaska,
south of a line from the Susitna River Delta to Point Possession
(approximately 61[deg]15'54'' N, 150[deg]41'07'' W, to 61[deg]02'19''
N, 150[deg]23'48'' W, WGS 1984) and north of a line from Rocky Cove to
Coal Cove (at approximately 59[deg]25'56'' N, 153[deg]44'25'' W and
59[deg]23'48'' N, 151[deg]54'28'' W WGS 1984), excluding Ursus Cove,
Iniskin Bay, Iliamna Bay, and Tuxedni Bay (see Regulation Promulgation,
Sec. 18.131 Specified geographic region where this subpart applies).
The ITR area includes all Alaska State waters and Outer Continental
Shelf (OCS) Federal waters within this area as well as all adjacent
rivers, estuaries, and coastal lands where sea otters may occur, unless
explicitly excluded.
The geographical extent of the Cook Inlet ITR region is
approximately 1.1 million hectares (ha) (2.7 million acres (ac)). For
descriptive purposes, the specified area is organized into two
[[Page 37718]]
marine areas within Cook Inlet: LCI (south of the Forelands to Homer)
and middle Cook Inlet (MCI; north of the Forelands to the Susitna River
and Point Possession). Project sites within these general areas include
TB, Granite Point, and the North Cook Inlet unit (NCI) in the MCI, and
the Iniskin Peninsula and the OCS waters of LCI.
Description of Specified Activities
The specified activities (also ``project activities'' or ``planned
activities'') include work related to oil and gas exploration,
development, production, transport, and the decommissioning of existing
facilities conducted by the applicant within a 5-year period. Hilcorp
and Harvest jointly plan to conduct the following activities: 2D and 3D
seismic surveys in LCI; routine operations of, maintenance of,
redevelopment of, and production drilling from existing oil and gas
facilities in MCI; geophysical and geohazard surveys in both regions;
drilling of two to four exploration wells in OCS waters of LCI and one
to three wells in MCI; construction of a dock facility in Chinitna Bay;
and decommissioning of an existing facility at the Drift River Terminal
in MCI. The following support activities will be conducted: Pipe and
pile driving using both vibratory and impact hammers; VSP; and pipeline
and platform maintenance. AGDC plans to install a natural gas pipeline
from the west side of MCI to the east side of LCI and to construct
processing and loading facilities on either side. These include a
product loading facility (PLF) and temporary and mainline materials
offloading facilities (TMOF, MMOF, MOF). Support activities for AGDC
will include pile driving, dredging, geophysical surveys, trenching,
fill placement, and anchor handling. Hilcorp, Harvest, and AGDC will
use vessels and aircraft to support the activities. Detailed
descriptions of the planned work are provided in the applicant's
updated petition for incidental take regulations for oil and gas
activities in Cook Inlet (June 2019), the stakeholder engagement plan
(April 2018), and the marine mammal monitoring and mitigation plan (May
2018). These documents can be obtained from the locations described
above in ADDRESSES. Table 1 summarizes the planned activities.
Table 1--Summary of Planned Activities Included in Incidental Take Regulation Petition
----------------------------------------------------------------------------------------------------------------
Total
Project component name & Geographic Year(s) anticipated
location region planned Seasonal timing duration (2019-
2024)
----------------------------------------------------------------------------------------------------------------
Anchor Point 2D seismic LCI, Anchor 2021 or 2022 April-October................ 30 days (10 days
survey. Point to in water
Kasilof. seismic).
OCS 3D seismic survey........ LCI OCS......... 2019 or 2020 April-October................ 45-60 days.
OCS geohazard survey......... LCI OCS......... 2019-2021 April-October................ 28 days.
OCS exploratory wells........ LCI OCS......... 2020-2022 February-November............ 40-60 days per
well, 2-4 wells
per year.
Iniskin Peninsula exploration LCI, west side.. 2020-2022 April-October................ 180 days.
and development.
Platform & pipeline MCI............. 2019-2024 April-October................ 180 days per
maintenance. year.
NCI subsea well geohazard MCI............. 2020 April-October................ 7 days.
survey.
NCI well abandonment activity MCI............. 2020 April-October................ 90 days.
TB area geohazard survey..... MCI............. 2020 April-October................ 14 days.
Granite Point development MCI............. 2019 June-October................. 120-150 days.
drilling.
Drift River terminal LCI, west side.. 2020-2023 April-October................ 120 days.
decommissioning.
Product loading facility pile MCI............. 2021-2023 April-October................ 162 days.
driving.
Material offloading MCI............. 2021-2022 April-October................ 360 days.
facilities dredging.
Material offloading MCI............. 2021-2022 April-October................ 482 days.
facilities pile driving.
Trenching, pipelay, burial... MCI............. 2023-2024 April-October................ 360 days.
Pipelay anchor handling...... MCI............. 2023-2024 April-October................ 76 days.
----------------------------------------------------------------------------------------------------------------
LCI = Lower Cook Inlet, MCI = Middle Cook Inlet, NCI = North Cook Inlet, TB = Trading Bay.
Description of Marine Mammals in the Specified Area
The northern sea otter is the only marine mammal under the
Service's jurisdiction that normally occupies Cook Inlet, Alaska. Sea
otters in Alaska are composed of three stocks. Those in Cook Inlet
belong to either the southwest Alaska stock or the southcentral Alaska
stock, depending on whether they occur west or east of the center of
Cook Inlet, respectively. A third stock occurs in southeast Alaska.
The southwest Alaska stock of the northern sea otter is the
southwest distinct population segment (DPS), which was listed as
threatened under the Endangered Species Act of 1973 (ESA; 16 U.S.C.
1531, et seq.) on August 9, 2005 (70 FR 46366). On October 8, 2009 (74
FR 51988), the Service finalized designation of 15,164 square
kilometers (km\2\) (or 5,855 square miles (mi\2\)) of critical habitat
for the Southwest DPS of sea otters. Critical habitat occurs in
nearshore marine waters ranging from the mean high-tide line seaward
for a distance of 100 meters (m), or to a water depth of 20 m. Detailed
information about the biology and conservation status of the listed DPS
can be found at https://www.fws.gov/alaska/fisheries/mmm/seaotters/otters.htm. Stock assessment reports for each of the three stocks are
available at https://www.fws.gov/alaska/pages/marine-mammal-management.
Sea otters may occur anywhere within the specified project area,
other than upland areas, but are not usually found north of about
60[deg]23'30'' N. The number of sea otters in Cook Inlet was estimated
from an aerial survey conducted by the Service in cooperation with the
U.S. Geological Survey (USGS) in May 2017 (Garlich-Miller et al. 2018).
The sea otter survey was conducted in all areas of Cook Inlet south of
approximately 60[deg]16'30'' N within the 40-m (131-feet (ft)) depth
contour, including Kachemak Bay in southeastern Cook Inlet and Kamishak
Bay in southwestern Cook Inlet. This survey was designed to estimate
abundance in Cook Inlet while accounting for the variable densities and
observability of sea otters in the region. Total abundance was
estimated to be 19,889 sea otters (standard error = 2,988). Within the
project area, the highest densities of sea otters were found in the
outer Kamishak Bay area, with 3.5 otters per km\2\, followed by the
eastern shore of Cook Inlet with 1.7 otters per km\2\.
Sea otters generally occur in shallow water near the shoreline.
They are most commonly observed within the 40-m (131-ft) depth contour
(USFWS 2014a, b), although they can be found in areas with deeper
water. Depth is generally correlated with distance to shore, and sea
otters typically remain within 1 to 2 kilometers (km) or 0.62 to 1.24
miles (mi) of shore (Riedman and Estes 1990). They tend to remain
closer to shore
[[Page 37719]]
during storms, and they venture farther out during calm seas (Lensink
1962; Kenyon 1969).
Sea otters are non-migratory and generally do not disperse over
long distances (Garshelis and Garshelis 1984). They usually remain
within a few kilometers of their established feeding grounds (Kenyon
1981). Breeding males remain for all or part of the year in a breeding
territory covering up to 1 km (0.62 mi) of coastline. Adult females
have home ranges of approximately 8 to 16 km (5 to 10 mi), which may
include one or more male territories. Juveniles move greater distances
between resting and foraging areas (Lensink 1962; Kenyon 1969; Riedman
and Estes 1990; Tinker and Estes 1996).
Although sea otters generally remain local to an area, they may
shift home ranges seasonally, and are capable of long-distance travel.
Otters in Alaska have shown daily movement distances greater than 3 km
(1.9 mi) at speeds up to 5.5 km/hr (3.4 mi per hour) (Garshelis and
Garshelis 1984). In eastern Cook Inlet, large numbers of sea otters
have been observed riding the incoming tide northward and returning on
the outgoing tide, especially in August. They are presumably feeding
along the eastern shoreline of Cook Inlet during the slack tides when
the seas are calm, and they remain in Kachemak Bay during periods of
less favorable weather (Gill et al. 2009; BlueCrest 2013). In western
Cook Inlet, otters appear to move in and out of Kamishak Bay in
response to seasonal changes in the presence of sea ice (Larned 2006).
Potential Effects of the Activities
Effects of Noise
The operations outlined in the Description of Specified Activities
and described in the applicant's updated petition have the potential to
result in take of sea otters by harassment from noise. Here we
characterize ``noise'' as sound released into the environment from
human activities that exceeds ambient levels or interferes with normal
sound production or reception by sea otters. The terms ``acoustic
disturbance'' or ``acoustic harassment'' are disturbances or harassment
events resulting from noise exposure. Potential effects of noise
exposure are likely to depend on the distance of the otter from the
sound source and the level of sound received by the otter. Project
components most likely to cause acoustic disturbance are shown in table
2. Temporary disturbance or localized displacement reactions are the
most likely to occur. With implementation of the mitigation and
monitoring measures described in Sec. 18.137 Mitigation, Sec. 18.138
Monitoring, and Sec. 18.139 Reporting requirements, no lethal take is
anticipated, and take by harassment (Level A and Level B) is expected
to be minimized to the greatest extent practicable.
Table 2--Project Components Planned by Hilcorp, Harvest, and Alaska
Gasline Development Corporation That Produce Noise Capable of Causing
Incidental Take by Harassment of Northern Sea Otters
------------------------------------------------------------------------
Project component name &
location Anticipated noise sources
------------------------------------------------------------------------
Anchor Point 2D seismic Marine: 1 source vessel with airgun, 1
survey. node vessel; Onshore/Intertidal: Shot
holes, tracked vehicles, helicopters.
OCS 3D seismic survey........ 1 source vessel with airguns, 1 support
vessel, 1 or 2 chase vessels to maintain
security around streamers, 1 or 2
mitigation vessels.
OCS geohazard survey......... 1 vessel with echosounders and/or
subbottom profilers.
OCS exploratory wells........ 1 jack-up rig, drive pipe installation,
support vessels, helicopters.
Iniskin Peninsula exploration Construction of causeway, dredging,
and development. vessels.
Platform & pipeline Vessels, water jets, helicopters, and/or
maintenance. sub-bottom profilers.
NCI subsea well geohazard 1 vessel with echosounders and/or
survey. subbottom profilers.
NCI well abandonment activity 1 jack-up rig, support vessel,
helicopters.
TB area geohazard survey..... 1 vessel with echosounders and/or
subbottom profilers.
TB area exploratory wells.... 1 jack-up rig, drive pipe installation,
support vessels, helicopters.
Drift River terminal Vessels.
decommissioning.
------------------------------------------------------------------------
OCS = outer continental shelf, NCI = North Cook Inlet, TB = Trading Bay.
Noise Levels
Whether a specific noise source will affect 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, the noise duration, and whether the noise is pulsed or
continuous. The actual noise level perceived by individual sea otters
will depend on distance to the source, whether the animal is above or
below water, atmospheric and environmental conditions, as well as
aspects of the noise emitted.
Noise levels herein are given in decibels referenced to 1 [mu]Pa
(dB re: 1 [mu]Pa) for underwater sound. All dB levels are
dBRMS unless otherwise noted; dBRMS refers to the
root-mean-squared dB level, the square root of the average of the
squared sound pressure level (SPL) typically measured over 1 second.
Other important metrics include the sound exposure level (SEL;
represented as dB re: 1 [mu]Pa\2\-s), which represents the total energy
contained within a pulse and considers both intensity and duration of
exposure, and the peak sound pressure (also referred to as the zero-to-
peak sound pressure or 0-p). Peak sound pressure is the maximum
instantaneous sound pressure measurable in the water at a specified
distance from the source and is represented in the same units as the
RMS sound pressure. See Richardson et al. (1995), G[ouml]tz et al.
(2009), Hopp et al. (2012), Navy (2014), for descriptions of acoustical
terms and measurement units in the context of ecological impact
assessment. A summary of the noises produced by the various components
of the planned activities is provided in tables 3 and 4.
[[Page 37720]]
Table 3--Summary of Sound Source Levels for the Planned Oil and Gas Activities by Hilcorp/Harvest Alaska and
Alaska Gasline Development Corporation (AGDC)
----------------------------------------------------------------------------------------------------------------
Sound pressure
Applicant Activity levels (dB re 1 Frequency Reference
[micro]Pa)
----------------------------------------------------------------------------------------------------------------
Hilcorp/Harvest Alaska, AGDC.... General vessel 145-175 dB rms at 10-1,500 Hz....... Richardson et al.
operations. 1 m. 1995; Blackwell
and Greene 2003;
Ireland and
Bisson 2016.
Hilcorp/Harvest Alaska, AGDC.... General aircraft 100-124 dB rms at 200 kHz.
High-resolution
sub-bottom
profiler: 2-24
kHz.
Low-resolution sub-
bottom profiler:
1-4 kHz.
Hilcorp/Harvest Alaska.......... Exploratory 137 dB rms at 1 m. cum). They also include weighting adjustments for the
sensitivity of different species to varying frequencies. PTS-based
injury criteria were developed from theoretical extrapolation of
observations of temporary threshold shifts (TTS) detected in lab
settings during sound exposure trials. Studies were summarized by
Finneran (2015). For otariid pinnipeds, PTS is predicted to occur at
232 dB peak or 203 dB SELcum for impulsive sound, or 219 dB
SELcum for non-impulsive (continuous) sound.
NMFS' criteria for take by Level A harassment represents the best
available information for predicting injury from exposure to underwater
sound among pinnipeds, and in the absence of data specific to otters,
we assume these criteria also represent appropriate exposure limits for
Level A take of sea otters.
NMFS (2018a) criteria do not identify thresholds for avoidance of
Level B take. For pinnipeds, NMFS has adopted a 160-dB threshold for
Level B take from exposure to impulse noise and a 120-dB threshold for
continuous noise (NMFS 1998; HESS 1999; NMFS undated). These thresholds
were developed from observations of mysticete (baleen) whales
responding to airgun operations (e.g., Malme et al. 1983a, b;
Richardson et al. 1986, 1995) and from equating Level B take with noise
levels capable of causing TTS in lab settings.
We have evaluated these thresholds and determined that the Level B
threshold of 120 dB for non-impulsive noise is not applicable to sea
otters. The 120-dB threshold is based on studies conducted by Malme et
al. in the 1980s, during which gray whales were exposed to experimental
playbacks of industrial noise. Based on the behavioral responses of
gray whales to the playback of drillship noise during a study at St.
Lawrence Island, Alaska, Malme et al. (1988) concluded that ``exposure
to levels of 120 dB or more would probably cause avoidance of the area
by more than one-half of the gray whales.'' Sea otters do not usually
occur at St. Lawrence Island, Alaska, but similar playback studies
conducted off the coast of California (Malme 1983a, 1984) included a
southern sea otter monitoring component (Riedman 1983, 1984). The 1983
and 1984 studies detected probabilities of avoidance in gray whales
comparable to those reported in Malme et al. (1988), but there was no
evidence of disturbance reactions or avoidance in southern sea otters.
The applicable Level B thresholds may also depend on the levels of
background noise present and the frequencies generated. NMFS
acknowledges that the 120-dB threshold may not be applicable if
background noise levels are high (NMFS undated), which is the case in
Cook Inlet, where ambient levels can often exceed 120 dB (Blackwell and
Greene 2003).
Thresholds developed for one species may not be appropriate for
another due to differences in their frequency sensitivities. Continuous
sound sources associated with the planned activities include vibratory
pile driving, vessel activities, use of a water jet, dredging,
trenching, and anchor handling. These are expected to produce low-
frequency broadband noise. For example, vibratory pile driving will
generate sound with frequencies that are predominantly lower than 2
kHz, and with the greatest pressure spectral densities at frequencies
below 1 kHz (Dahl et al. 2015). Sea otters are capable of hearing down
to 125 Hz, but have relatively poor hearing sensitivity at frequencies
below 2 kHz (Ghoul and Reichmuth 2014). During a project that occurred
in Elkhorn Slough, California, sound levels ranging from approximately
135 to 165 dB during vibratory pile driving elicited no clear pattern
of disturbance or avoidance among southern sea otters in areas exposed
to these levels of underwater sound (ESNERR 2011). In contrast, gray
whales are in the group of marine mammals believed to be most sensitive
to low-frequency sounds, with an estimated audible frequency range of
approximately 10 Hz to 30 kHz (Finneran 2015). Given the different
range of frequencies to which sea otters and gray whales are sensitive,
the NMFS 120-dB threshold based on gray whale behavior is not useful
for predicting sea otter behavioral responses to low-frequency sound.
Although no specific thresholds have been developed for sea otters,
several alternative behavioral response thresholds have been developed
for pinnipeds. Southall et al. (2007, 2019) assessed behavioral
response studies, found considerable variability among pinnipeds, and
determined that exposures between approximately 90 to 140 dB generally
do not appear to induce strong behavioral responses in pinnipeds in
water, but behavioral effects, including avoidance, become more likely
in the range between 120 to 160 dB, and most marine mammals showed
some, albeit variable, responses to sound between 140 to 180 dB. Wood
et al. (2012) later adapted the approach identified in Southall et al.
(2007) to develop a probabilistic scale for marine mammal taxa at which
10 percent, 50 percent, and 90 percent of individuals exposed are
assumed to produce a behavioral response. For many marine mammals,
including pinnipeds, these response rates were set at sound pressure
levels of 140, 160, and 180 dB respectively.
Thresholds based on TTS have been used as a proxy for Level B
harassment (i.e., 70 FR 1871, January 11, 2005; 71 FR 3260, January 20,
2006; and 73 FR 41318, July 18, 2008). Southall et al. (2007) derived
TTS thresholds for pinnipeds based on 212 dB peak and 171-dB
SELcum. Kastak et al. (2005) found exposures resulting in
TTS in pinnipeds ranging from 152 to 174 dB (183-206 dB SEL). Kastak et
al. (2008) demonstrated a persistent TTS, if not a PTS, after 60
seconds of 184 dB SEL. Kastelein et al. (2012) found small but
statistically significant TTSs at approximately 170 dB SEL (136 dB, 60
min) and 178 dB SEL (148 dB, 15 min). Finneran (2015) summarized these
and other studies, and NMFS (2018a) has used the data to develop TTS
threshold for otariid pinnipeds of 188 dB SELcum for
impulsive sounds and 199 dB SELcum for non-impulsive sounds.
Based on the lack of a disturbance response or any other reaction
by sea otters to the 1980s playback studies and the absence of a clear
pattern of disturbance or avoidance behaviors attributable to
underwater sound levels up to about 160 dB resulting from
[[Page 37722]]
vibratory pile driving and other sources of similar low-frequency
broadband noise, we assume 120 dB is not an appropriate behavioral
response threshold for sea otters exposed to continuous underwater
noise. We assume, based on the work of NMFS (2018a), Southall et al.
(2007, 2019), and others described here, that either a 160-dB threshold
or a 199-dB SELcum threshold is likely to be the best
predictor of Level B take of sea otters for continuous noise exposure,
using southern sea otters and pinnipeds as a proxy, and based on the
best available data. When behavioral observations during vibratory pile
driving (ESNERR 2011) and results of behavioral response modelling
(Wood et al. 2012) are considered, the application of a 160-dB rms
threshold is most appropriate.
Exposure to impulsive sound levels greater than 160 dB can elicit
behavioral changes in marine mammals that might be detrimental to
health and long-term survival where it disrupts normal behavioral
routines. Thus, using information available for other marine mammals as
a surrogate, and taking into consideration the best available
information 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 ITR based on the work of Ghoul and
Reichmuth (2012a, b), McShane et al. (1995), NOAA (2005), Riedman
(1983), Richardson et al. (1995), and others. Exposure to unmitigated
in-water noise levels between 125 Hz and 38 kHz that are greater than
160 dB--for both impulsive and non-impulsive sound sources--will be
considered by the Service as Level B take; thresholds for potentially
injurious Level A take will be 232 dB peak or 203 dB SEL for impulsive
sounds and 219 dB SEL for continuous sounds (table 5).
The area in which underwater noise in the frequency range of sea
otter hearing will exceed thresholds, is termed the ``area of
ensonification'' or ``zone of ensonification.'' The ensonification zone
in which noise levels exceed thresholds for Level A take is often
referred to as the Level A harassment zone. The Level B harassment zone
likewise includes areas ensonified to thresholds for Level B take of
sea otters.
Table 5--Summary of Thresholds for Predicting Level A and Level B Take of Northern Sea Otters From Underwater
Sound Exposure in the Frequency Range 125
----------------------------------------------------------------------------------------------------------------
Injury (Level A) threshold Disturbance (Level B) threshold
Marine mammals -------------------------------------------------------------------------------
Impulsive \1\ Non-impulsive \1\ All
----------------------------------------------------------------------------------------------------------------
Sea otters...................... 232 dB peak; 203 dB 219 dB SELCUM...... 160 dB rms.
SELCUM.
----------------------------------------------------------------------------------------------------------------
\1\ Based on National Marine Fisheries Service acoustic exposure criteria for take of otariid pinnipeds (NMFS
2018a).
SELCUM = cumulative sound exposure level.
Noise-Generating Activities
The components of the specified activities that have the greatest
likelihood of exposing sea otters to underwater noise capable of
causing Level A or Level B take include geophysical surveys, pile
driving, drilling activities, and anchor handling associated with
pipeline construction. Vessel and aircraft operations also have the
ability to expose otters to sound that may cause disturbance. A brief
description of potential impacts follows.
Geophysical Surveys--Airgun arrays used in seismic surveys to
locate potential hydrocarbon-bearing geologic formations 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). There is no
empirical evidence that exposure to pulses of airgun sound is likely to
cause serious injury or death in any marine mammal, even with large
arrays of airguns (Southall et al. 2007). But high-level noise exposure
has been implicated in mass stranding events among whales (e.g., see
Cox et al. 2006), and with source levels of up to 260 dB, the potential
of seismic airgun arrays to acoustically injure marine mammals at close
proximity must be considered.
In addition to seismic surveys for hydrocarbon-bearing formations,
geophysical surveys are conducted to produce imagery of sea-floor
surfaces and substrates on a finer spatial scale. Sounds produced by
the instruments used for these surveys vary in terms of frequency
bands, source levels, repetition rates, and beam widths. Operating
frequencies range from roughly 300 Hz to several hundred kHz with peak-
to-peak source levels ranging from 170 to 240 dB (Crocker and
Fratantonio 2016).
Pipe/Pile Driving--During the course of pile driving, a portion of
the kinetic energy from the hammer is lost to the water column in the
form of sound. Levels of underwater sounds produced during pile driving
are dependent upon the size and composition of the pile, the substrate
into which the pile is driven, bathymetry, physical and chemical
characteristics of the surrounding waters, and pile installation method
(impact versus vibratory hammer) (Illingworth and Rodkin 2007, 2014;
Denes et al. 2016).
Both impact and vibratory pile installation produce underwater
sounds of frequencies predominantly lower than 2.5 kHz, with the
highest intensity of pressure spectral density at or below 1 kHz (Denes
et al. 2016; Dahl et al. 2015; Illingworth and Rodkin 2007). Source
levels of underwater sounds produced by impact pile driving tend to be
higher than for vibratory pile driving; however, both methods of
installation can generate underwater sound levels capable of causing
behavioral disturbance or hearing threshold shift in marine mammals,
and both methods will be used in Cook Inlet.
Drilling Operations--For drilling operations, two project
components have the potential to disturb sea otters: Installing the
drive pipe at each well prior to drilling; and VSP operations that may
occur at the completion of each well drilling. The types of underwater
sounds generated by these activities are discussed in ``Pile Driving''
and ``Geophysical Surveys,'' respectively. Drilling and the associated
noise from pumps and generators on the drill rig is not expected to
produce underwater noise levels that will affect sea otters (e.g., see
Richardson et al. 1995; Spence et al. 2007; Marine Acoustics, Inc.
2011; Illingworth and Rodkin 2014).
Aircraft Overflights--Richardson et al. (1995) presented analyses
of recordings of sounds produced by a Bell 212 helicopter. The
estimated source levels for two of the flights were 149 and 151 dB re 1
[micro]Pa-m, and underwater received levels were 109 dB when the
aircraft flew at an altitude of 152 m (500 ft) and
[[Page 37723]]
107 dB at a flight altitude of 305 m (1,000 ft). Received sound levels
in air at the water surface would be 81 and 75 dB re 20 [micro]Pa for
flights at 152 and 305 m (500 and 1,000 ft), respectively.
Anchor Handling--The characteristics of sounds produced by vessels
are a product of several variables pertaining to the specifications of
the vessel, including the number and type of engines, propeller shape
and size, and the mechanical condition of these components. Operational
status of the vessel, such as towing heavy loads or using bow
thrusters, can significantly affect the levels of sounds emitted by the
same vessel at different times (Richardson et al. 1995). Manipulation
of anchors for the laying of the AGDC pipeline will involve vessel
operations that are likely to be substantially louder than normal
transit. Data from recent exploratory drilling activities in the
Chukchi and Beaufort Seas indicate that anchor handling can
intermittently produce sounds likely greater than 190 dB; the source
level of the anchor-handling vessel was estimated to be 188 dB (LGL/
JASCO/Greeneridge 2014). It is not known whether anchor handling will
produce similar noise levels in Cook Inlet, but it will occur in areas
where sea otters are uncommon and unlikely to be affected.
Airborne Sounds
The NMFS (2018a) guidance neither addresses thresholds for
preventing injury or disturbance from airborne noise, nor provides
thresholds for avoidance of Level B take. However, a review of
literature by Southall et al. (2007) suggested thresholds for PTS and
TTS for sea lions exposed to non-pulsed airborne noise of 172.5 and 159
dB re (20 [micro]Pa)\2\-s SEL. Behavioral responses to overflights are
addressed in Responses to Activities.
Conveyance of underwater noise into the air is of little concern
since the effects of pressure release and interference at the water's
surface, which scatter and reflect sound, reduce underwater noise
transmission into the air. For activities that create both in-air and
underwater sounds, such as pile driving, we will estimate take based on
parameters for underwater noise transmission. Because sound energy
travels more efficiently through water than through air, this
estimation will also account for exposures to animals at the surface.
Aircraft are the most significant source of airborne sounds.
Proposed flights are to be conducted at an altitude of 305 m (1,000 ft)
except during takeoff and landing. At the surface of the water, the
received sound level from a helicopter flown at this altitude is
roughly 75 dB re 20 [micro]Pa (see ``Noise-Generating Activities''),
and so threshold shift is extremely unlikely.
Loud screams are used to communicate between pups and mothers at
the surface (McShane et al. 1995), but sea otters do not appear to
communicate vocally under water, and they do not use sound to detect
prey. Although masking of these crucial airborne calls is possible, the
duration of sound from aircraft will be brief and therefore unlikely to
result in separation of females from pups.
Effects on Habitat and Prey
Habitat areas of significance for sea otters exist in the project
area. Sea otter critical habitat was designated under the ESA (74 FR
51988, October 8, 2009). In Cook Inlet, critical habitat occurs along
the western shoreline south of approximately Redoubt Point. It extends
from mean high-tide line out to 100 m (328.1 ft) from shore or to the
20-m (65.6-ft) depth contour. Physical and biological features of
critical habitat essential to the conservation of sea otters include
the benthic invertebrates (e.g., red sea urchins (Mesocentrotus
franciscanus), blue mussels (Mytilus spp.), butter clams (Saxidomus
giganteus), etc.) eaten by otters and the shallow rocky areas and kelp
(e.g., bull kelp (Nereocystis luetkeana) and dragon kelp (Eualaria
fistulosa)) beds that provide cover from predators. Other important
habitat in the applicant's project area includes outer Kamishak Bay
between Augustine Island and Iniskin Bay within the 40-m (131-ft) depth
contour where high densities of otters have been detected.
The applicant's planned activities include drilling, dredging,
trenching, pile driving, and dock construction. These activities would
change the physical characteristics of localized areas of habitat.
Construction would result in seafloor disturbance. Docks can increase
seafloor shading, which affects the amount of light penetration on the
seafloor. Water quality may be affected by drilling-related discharges
within limits permitted by the State of Alaska.
Sampling efforts at borrow and disposal areas before and after
dredging activity have produced mixed results in terms of whether
dredging causes significant changes to the productivity and diversity
of infaunal benthic and epibenthic invertebrate communities (Fraser et
al. 2017; Angonesi et al. 2006). The areas where dredging activities
are proposed include a materials loading facility at Nikiski and along
the planned AGDC pipeline route between Nikiski and Beluga; the
proposed disposal area is just west of Nikiski. This is beyond the
northern limit of sea otter distribution in Cook Inlet, so effects of
dredging upon invertebrate communities would not affect availability of
prey to sea otters.
In addition to the disturbances outlined above to sea otters or
their designated critical habitat, survey and construction 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, otters will also eat kelp, turban snails
(Tegula spp.), octopuses (e.g., Octopus spp.), barnacles (Balanus
spp.), sea stars (e.g., Pycnopodia helianthoides), scallops (e.g.,
Patinopecten caurinus), rock oysters (Saccostrea spp.), worms (e.g.,
Eudistylia spp.), and chitons (e.g., Mopalia spp.) (Riedman and Estes
1990).
Limited research has been conducted on the effects of noise 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 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. Pearson
et al. (1994) did not observe any statistically significant effects on
Dungeness crab (Cancer magister) larvae shot as close as 1 m from a
231-dB source. Further, Christian et al. (2004) did not find any
behavioral or significant health impacts to snow crabs (Chionoecetes
opilio) exposed to seismic noise. The only effect noted was a reduction
in the speed of egg development after exposure to noise levels (221 dB
at 2 m), far higher than what bottom-dwelling crabs could be exposed to
by seismic guns. 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 cephalopod species have complex statocysts
(Nixon and Young 2003) that resemble the otolith organs of fish that
may allow them to detect sounds (Budelmann 1992).
Some species of invertebrates have shown temporary behavioral
changes in the presence of increased sound levels. Fewtrell and
McCauley (2012) reported increases in alarm behaviors in wild-caught
captive reef squid (Sepioteuthis australis) exposed to seismic airguns
at noise levels between 156-161 dB. Additionally, captive crustaceans
have
[[Page 37724]]
changed behaviors when exposed to simulated sounds consistent with
those emitted during seismic exploration and pile-driving activities
(Tidau and Briffa 2016).
In general, there is little knowledge regarding effects of sound in
marine invertebrates or how invertebrates are affected by high noise
levels (Hawkins and Popper 2012). A review of literature pertaining to
effects of seismic surveys on fish and invertebrates (Carroll et al.
2016) noted that there is a wide disparity between results obtained in
field and laboratory settings. Some of the reviewed studies indicate
the potential for noise-induced physiological and behavioral changes in
a number of invertebrates. However, changes were observed only when
animals were housed in enclosed tanks and many were exposed to
prolonged bouts of continuous, pure tones. We would not expect similar
results in open marine conditions. Given the short-term duration of
sounds produced by each component of the proposed work, it is unlikely
that noises generated by survey and construction activities will have
any lasting effect on sea otter prey.
Potential Impacts From an Oil Spill or Unpermitted Discharge
We provided discussion of relevant impacts to sea otters from oil
spills and unpermitted discharges in our Federal Register notice of
proposed rulemaking (84 FR 10224, March 19, 2019) and do not repeat
that information here. Adverse impacts of exposure to oil is well
documented for sea otters (e.g., Kooyman et al. 1976; Baker et al.
1981; Costa and Kooyman 1982, 1984; Engelhardt 1983; Lipscomb 1996;
Bickham 1998; Monson 2000; Albers 2003; Peterson 2003). An oil spill or
unpermitted discharge is an illegal act, and ITRs do not authorize take
of sea otters caused by illegal or unpermitted activities. Typical
spills that may result from the proposed activities are relatively
small in scale and are not likely to affect otters. A large spill could
affect large numbers of otters, but these events are rare. We do not
anticipate effects to sea otters as a result of oil spills from this
activity.
Collisions
Vessel collisions with marine mammals can result in death or
serious injury. Wounds resulting from ship strike may include massive
trauma, hemorrhaging, broken bones, or propeller lacerations (Knowlton
and Kraus 2001). An animal at the surface may be struck directly by a
vessel, a surfacing animal may hit the bottom of a vessel, or an animal
just below the surface may be cut by a vessel's propeller. Mortality
associated with boat strike has been identified from recovery of
carcasses with lacerations indicative of propeller injuries (e.g., Wild
and Ames 1974; Morejohn et al. 1975). From 1998 to 2001, boat strike
was identified as the cause of death for 5 of 105 southern sea otter
mortalities (Kreuder et al. 2003). From 2006 through 2010, evidence
indicates that 11 southern sea otters were likely struck by boats (USGS
and California Department of Fish and Game, unpublished data cited in
77 FR 59211-59220, September 26, 2012). From January 2003 to May 2013,
researchers recovered 35 southern sea otters with trauma consistent
with impact from a boat hull or propeller. These data suggest a rate of
boat-strike mortality in California of 2.6 otters per year, or about
0.1 percent of the population size.
Boat strike has been documented as a cause of death across all
three stocks of northern sea otters in Alaska. Since 2002, the Service
has undertaken a health and disease study of sea otters in Alaska in
which the Service conducts necropsies on sea otter carcasses to
determine cause of death, disease incidence, and status of general
health parameters. Of 1,433 necropsies conducted during 24 years, boat
strike or blunt trauma was identified as a definitive or presumptive
cause of death in 64 cases (4 percent) (USFWS unpublished data). It has
been determined in most of these cases that, while trauma was the
ultimate cause of death, there was a contributing factor, such as
disease or biotoxin exposure, which incapacitated the animal and made
it more vulnerable to boat strike (USFWS 2014).
In Alaska, the annual rate of documented mortality from boat strike
was similar to that reported for California: 2.7 otters per year (USFWS
unpublished data). However, compared to otters in California, Alaska
otters belong to much larger and more dispersed populations where
carcass recovery is lower. Instances of vessel collision are likely to
be underreported, and the probability of collision is unknown.
Likelihood of vessel strikes involving sea otters appears to be
primarily related to vessel speed. Most collision reports have come
from small, fast-moving vessels (NMFS 2003). The severity of injuries
to marine mammals during a boat strike also depends on vessel speed,
with the probability of death or serious injury increasing as vessel
speed increases (Laist et al. 2001; Vanderlaan and Taggart 2007).
Because sea otters spend a considerable portion of their time at the
surface of the water, they are typically visually aware of approaching
boats and are able to move away if a vessel is not traveling too
quickly.
The probability of the specified activities in Cook Inlet causing a
sea otter/vessel collision is very low for three reasons: First, most
of the work will occur in lower-density regions of Cook Inlet; second,
the project work will involve slow-moving, noisy vessels that sea
otters can more easily avoid; and third, the specified activities will
constitute only a small fraction of the total level of vessel traffic
in the region, which increases the likelihood that otters in the
project area are accustomed to avoiding vessels and will successfully
avoid collisions with project vessels.
The AGDC pipeline work and work by Hilcorp and Harvest on
maintenance of existing facilities will be conducted in MCI, in areas
that are outside of the normal range of sea otters. The unusual
occurrence of otters in MCI makes vessel collisions extremely unlikely.
Hilcorp and Harvest will conduct their 3D seismic work in offshore
areas of LCI where otter densities are also low. They will conduct 2D
seismic work along the eastern shoreline of LCI where densities are
higher, but vessel speeds during the specified activities will be slow.
Hilcorp/Harvest's seismic vessels would travel at approximately 4 knots
(kn) or 7.4 km per hour (km/hr) while towing seismic survey gear and a
maximum of 4.5 kn (8.3 km/hr) while conducting geophysical surveys.
Vessel speed during rig towing will generally be less than 5 kn. AGDC's
pipeline construction operations will proceed at similar slow speeds.
Anchor handling will occur at about 3 kn. For comparison, freighters in
Cook Inlet travel at 20 to 24 kn (Eley 2006), and small recreational
vessels may travel at 40 kn.
The applicant's support vessels and vessels in transit will travel
at faster speeds; for example, Hilcorp/Harvest's maintenance activities
will require the use of dive vessels, typically ranging up to 21 m (70
ft) in length and capable of approximately 7 kn (13 km/hr). The risk of
collision is thus reduced, but not eliminated, by the predominance of
slow-moving vessel work in areas of low density.
Commercial and recreational vessels are much more common in both
space and time than are geophysical survey activities, drilling support
operations, and pipeline work. Based on U.S. Coast Guard records and
other local sources of information compiled by Eley (2006), 704 large
vessels, other than fuel barges in domestic trade, called at Cook Inlet
ports from January 1, 2005, through July 15, 2006. Almost two-thirds
(65 percent)
[[Page 37725]]
of the calls were made by container vessels, cargo, or ferries. Twenty-
nine percent (29 percent) of the vessel traffic was gas or liquid
tankships calling primarily at Nikiski. Bulk carriers and general cargo
ships represented 6 percent. Tugs and fishing and passenger vessels
combined represented 2 percent of the Cook Inlet vessel traffic. Tugs
made approximately 150 fuel barge transits a year, assisted in docking
and undocking ships in Nikiski and Anchorage, and moved miscellaneous
deck and gravel barges in and out of the Port of Anchorage. Although
small vessels are less common than larger ships, they are the most
likely source of collision due to faster speeds and their presence in
shallow water where sea otters are common. In 2005, there were 570
commercial fishing vessels registered in the Cook Inlet salmon/
groundfish fleet. Of these, 86 percent were 31-40 ft in length. Vessels
in this size class typically travel at up to 30 kn while in transit.
The high level of ship traffic in Cook Inlet allows many sea otters in
Cook Inlet to habituate to vessels. This will reduce risk of collision
for the project activities when vessels are in transit.
Although the likelihood of a project vessel striking a sea otter is
low, we intend to require mitigation measures to reduce the risk of
ship strike in all LOAs. We anticipate that vessel collisions involving
a seismic-data-acquisition vessel towing gear or vessels conducting
geophysical operations are unlikely given the rarity of documented
collisions, the low densities of otters in most of the project areas,
the frequent vessel traffic to which otters have become accustomed, and
the slow vessel speeds. Vessels in transit and support vessels
travelling at greater rates of speed are more likely to cause
collisions.
Mitigation measures for reducing the probability of ship strike
include speed reductions during periods of low visibility, required
separation distances from observed otters, avoidance of nearshore
travel, and use of navigation channels, when practicable. We believe
these measures will further reduce the risk of collision. Given the
required mitigation measures, the relatively slow speed of most of the
project vessels, the presence of marine mammal observers, and the short
duration of many of the activities, we believe that the possibility of
ship strike is discountable. No incidental take resulting from ship
strike is anticipated, and this potential effect of the specified
activity will not be discussed further in the following analysis.
Characterizing Take
In the previous section, we discussed the components of the project
activities that have the potential to affect sea otters. Here we
describe and categorize the physiological and behavioral effects that
can be expected based on documented responses to human activities
observed during sea otter studies. We also discuss how these behaviors
are characterized under the MMPA.
An individual sea otter's reaction to a human activity will depend
on its prior exposure to the activity, its need to be in the particular
area, its physiological status, or other intrinsic factors. The
location, timing, frequency, intensity, and duration of the encounter
are among the external factors that will also influence the animal's
response.
Relatively minor reactions such as increased vigilance or a short-
term change in direction of travel are not likely to disrupt
biologically important behavioral patterns and are not considered take
by harassment. These types of responses typify the most likely
reactions of the majority of sea otters that will be exposed to the
applicant's activities.
Reactions capable of causing injury are characterized as Level A
harassment events. Examples include separation of mothers from young or
repeatedly flushing sea otters from a haulout. Exposure to noise
capable of causing PTS is also considered take by Level A harassment.
Intermediate reactions that disrupt biologically significant
behaviors are considered Level B harassment under the MMPA. The Service
has identified the following sea otter behaviors as indicating possible
Level B take:
Swimming away at a fast pace on belly (i.e., porpoising);
Repeatedly raising the head vertically above the water to
get a better view (spyhopping) while apparently agitated or while
swimming away;
In the case of a pup, repeatedly spyhopping while hiding
behind and holding onto its mother's head;
Abandoning prey or feeding area;
Ceasing to nurse and/or rest (applies to dependent pups);
Ceasing to rest (applies to independent animals);
Ceasing to use movement corridors along the shoreline;
Ceasing mating behaviors;
Shifting/jostling/agitation in a raft so that the raft
disperses;
Sudden diving of an entire raft;
Flushing animals off a haulout.
This list is not meant to encompass all possible behaviors; other
situations may also indicate Level B take. It is also important to note
that, depending on the duration and severity of the above-described
behaviors, such responses could constitute take by Level A harassment,
e.g., repeatedly flushing sea otters from a haulout versus a single
flushing event.
Direct and Indirect Effects
The reactions of wildlife to disturbance can range from short-term
behavioral changes to long-term impacts that affect survival and
reproduction. Most sea otters will respond to human disturbance with
nonlethal reactions that are similar to antipredator responses (Frid
and Dill 2002). Sea otters are susceptible to predation, particularly
from killer whales and eagles, and have a well-developed antipredator
response to perceived threats. Sea otters will swim away, dive, or hide
among rocks or kelp, and will sometimes spyhop (vertically raise its
head out of the water, presumably to look around) or splash when
threatened. Limbaugh (1961) reported that sea otters were apparently
undisturbed by the presence of a harbor seal (Phoca vitulina), but they
were quite concerned with the appearance of a California sea lion. They
demonstrated their fear by actively looking above and beneath the water
when a sea lion was swimming nearby.
Although an increase in vigilance or a flight response is
nonlethal, a tradeoff occurs between risk avoidance and energy
conservation (Frid and Dill 2002). For example, southern sea otters in
areas with heavy recreational boat traffic demonstrated changes in
behavioral time budgeting showing decreased time resting and changes in
haulout patterns and distribution (Benham 2006; Maldini et al. 2012).
In an example described by Pavez et al. (2015), South American sea
lions (Otaria byronia) visited by tourists exhibited an increase in the
state of alertness and a decrease in maternal attendance and resting
time on land, thereby potentially reducing population size. In another
example, killer whales (Orcinus orca) that lost feeding opportunities
due to boat traffic faced a substantial (18 percent) estimated decrease
in energy intake (Williams et al. 2006). Such disturbance effects can
have population-level consequences. Increased disturbance rates have
been associated with a decline in abundance of bottlenose dolphins
(Tursiops sp.) (Bejder et al. 2006; Lusseau et al. 2006).
These examples illustrate direct effects on survival and
reproductive success, but disturbances can also have indirect effects.
When disturbed by
[[Page 37726]]
noise, animals may respond behaviorally (e.g., escape response), as
well as physiologically (e.g., increased heart rate, hormonal response)
(Harms et al. 1997; Tempel and Gutierrez 2003). In the absence of an
apparent behavioral response, an animal exposed to noise disturbance
may still experience stress and direct energy away from fitness-
enhancing activities such as feeding and mating. The energy expense and
physiological effects could ultimately lead to reduced survival and
reproduction (Gill and Sutherland 2000; Frid and Dill 2002). Changes in
behavior from anthropogenic disturbance can also include latent
agonistic interactions between individuals (Barton et al. 1998).
Chronic stress can lead to weakened reflexes, lowered learning
responses (Welch and Welch 1970; van Polanen Petel et al. 2006),
compromised immune function, decreased body weight, and abnormal
thyroid function (Selye 1979).
The type and extent of response may be influenced by intensity of
the disturbance (Cevasco et al. 2001), the extent of previous exposure
to humans (Holcomb et al. 2009), the type of disturbance (Andersen et
al. 2012), and the age and/or sex of the individuals (Shaughnessy et
al. 2008; Holcomb et al. 2009). Despite the importance of understanding
the effects of disturbance, few controlled experiments or field
observations have been conducted on sea otters to address this topic.
Responses to Activities
The available studies of sea otter behavior suggest that sea otters
may be more resistant to the effects of sound disturbance and other
human activities than some other marine mammals. For example, at
Soberanes Point, California, Riedman (1983) examined changes in the
behavior, density, and distribution of southern sea otters that were
exposed to recorded noises associated with oil and gas activity. The
underwater sound sources were played at a level of 110 dB and a
frequency range of 50 to 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 (in\3\). 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 ( Development of marine mammal monitoring and mitigation
plans;
Establishment of an exclusion zone (EZ) and safety zone
(SZ) during noise-generating work;
Visual mitigation monitoring by designated protected
species observers (PSOs);
Site clearance before startup;
Shutdown procedures;
Ramp-up procedures; and
Vessel strike avoidance measures.
This ITR establishes the process for evaluating specific activities
in specific project areas and determining the appropriate mitigation
measures to be included in an LOA. A marine mammal mitigation and
monitoring plan (4MP) is required for all LOAs. The 4MP identifies the
specific avoidance and minimization measures an applicant will take to
reduce effects to otters. It describes the project in detail, assesses
the effects, identifies effective means to avoid effects, and describes
specific methods for limiting effects when they cannot be avoided.
During ``noise-generating work'' (work that creates underwater
sound louder than 160 dB and within the frequency hearing range of sea
otters), an applicant will establish and monitor an EZ. The EZ is
defined as the area surrounding a sound source in which all operations
must be shut down in the event a sea otter enters or is about to enter
this zone based on distances to Level A thresholds. Any otter detected
within this zone will be exposed to sound levels likely to cause take
by Level A harassment. The SZ is an area larger than the EZ and is
defined as the area in which otters may experience noise above the
Level B exposure threshold. Sea otters observed inside the SZ are
likely to be disturbed by underwater noise, and each otter within the
SZ will be counted as one Level B take. In the event a sea otter is in
or about to enter the zone, operations will be powered down, when
practicable, to minimize take. Radii of each SZ and EZ will be
specified in each LOA issued under this ITR. The methodology for
calculation of the radii will be described in each LOA and is
identified in Sec. 18.137 Mitigation. Sound source levels will be
monitored and evaluated in the field prior to conducting 2D and 3D
seismic surveys. This on-site sound source verification (SSV) testing
will be used to determine the size of the SZ and EZ for these
activities. A minimum 10-m (33-ft) shutdown zone will be observed for
all in-water construction and heavy machinery.
PSOs will be stationed on the source vessel or at a suitable
vantage point with maximum view of the SZ and EZ. The PSOs will
determine that the EZ is clear of sea otters prior to the start of
daily activities or if activities have been stopped for longer than a
30-minute period. The PSOs will ensure that no sea otters are observed
in the EZ for a period of 30 minutes prior to work commencing.
For the 2D survey, PSOs will be stationed on the source vessel
during all seismic operations and geohazard surveys when the sub-bottom
profilers are used. Because of the proximity to land, PSOs may also be
stationed on land to augment the viewing area. For the 3D survey, PSOs
will be stationed on at least two of the project vessels: The source
vessel and the chase vessel. For the vertical seismic profiling, PSOs
will be stationed on the drilling rig. For geohazard surveys, PSOs will
be stationed on the survey vessel. The viewing area may be augmented by
placing PSOs on a vessel specifically for mitigation purposes or using
an unmanned aircraft system (drone). If drones will be used in areas
with sea
[[Page 37728]]
otters, mitigation measures will be required to ensure drone use does
not disturb otters. These measures may include maintaining a minimum
altitude and horizontal distance no less than 100 m away from otters,
conducting continuous visual monitoring by PSOs, and ceasing activities
in response to sea otter behaviors indicating any reaction to drones.
A power-down procedure will be in place during seismic work. It
will provide the option of reducing the number of airguns in use, which
reduces the EZ or SZ radius. Alternatively, a shutdown procedure may be
necessary, during which all airgun activity is suspended immediately.
During a power-down, a single airgun (``mitigation gun'') may be
operated, maintaining a sound source with a much-reduced EZ. If a sea
otter is detected outside of either the SZ or EZ but is likely to enter
that zone, the airguns may be powered down before the animal is within
the radius, as an alternative to a complete shutdown. Likewise, if a
sea otter is already within the SZ when first detected, the airguns may
be powered down if this is a reasonable alternative to an immediate
shutdown. If a sea otter is already within the EZ when first detected,
the airguns will be shut down immediately. All power-down events will
be at the discretion of the operator in cooperation with the PSOs. The
applicant has determined that it is not practicable to power down in
response to all sea otters within the SZ, and that to do so would
incapacitate the 2D and 3D seismic operations. Because power-down
events will be discretionary, all otters within the SZ will be assumed
to experience Level B take regardless of whether a power-down is
conducted. Although there is no calculated reduction of take estimated
for this mitigation measure due to uncertainty in its application, it
is expected that some unquantified benefits to sea otters will be
realized whenever the operator powers down to reduce or avoid sea otter
noise exposures.
A shutdown will occur when all underwater sound generation that is
louder than 160 dB and within the frequency hearing range of sea otters
is suspended. The sound source will be shut down completely if a sea
otter approaches the EZ or appears to be in distress due to the noise-
generating work. The shutdown procedure will be accomplished as soon as
practicable upon the determination that a sea otter is either in or
about to enter the EZ, and generally within several seconds. Following
a shutdown, noise-generating work will not resume until the sea otter
has cleared the EZ. Any shutdown due to a sea otter sighting within the
EZ must be followed by a 30-minute all-clear period and then a
standard, full ramp-up. Any shutdown for other reasons resulting in the
cessation of the sound source for a period greater than 30 minutes must
also be followed by full ramp-up procedures.
A ``ramp-up'' procedure will be in place to gradually increase
sound volume at a specified rate. Ramp-up is used at the start of
airgun operations, including after a power-down, shutdown, or any
period greater than 10 minutes in duration without airgun operations.
The rate of ramp-up will be no more than 6 dB per 5-minute period.
Ramp-up will begin with the smallest gun in the array that is being
used for all airgun array configurations. The ramp-up procedure for
pipe/pile driving involves initially starting with soft strikes or a
reduced level of energy. If the complete EZ has not been visible for at
least 30 minutes prior to the start of operations, operation of a
mitigation gun may be required during the interruption of seismic
survey operations prior to commencing ramp-up procedures. It will not
be permissible to ramp up the full array from a complete shutdown in
thick fog or at other times when the outer part of the Level A EZ is
not visible. Ramp-up of the airguns will not be initiated if a sea
otter is sighted within the EZ at any time.
A speed or course alteration is appropriate if a sea otter is
detected outside the EZ and, based on its position and relative motion,
is likely to enter the EZ, and a vessel's speed and/or direct course
may, when practical and safe, be changed. This technique can be used in
coordination with a power-down procedure. The sea otter activities and
movements relative to the seismic and support vessels will be closely
monitored to ensure that the sea otter does not approach within the EZ.
If the sea otter appears likely to enter the EZ, further mitigative
actions will be taken, i.e., further course alterations, power-down, or
shutdown of the airguns.
This ITR establishes the stakeholder engagement process that the
applicant is required to undertake in order to obtain an LOA for
incidental take of sea otters. This process is an ongoing collaborative
process between the applicant, the Service, and subsistence users of
sea otters. Stakeholder engagement efforts for the specified activities
have been ongoing since mid-2018 and have indicated that a plan of
cooperation (POC) is necessary for the Hilcorp and Harvest 3D seismic
work. The POC must include a schedule for meeting with the affected
communities, both prior to and while conducting the activities, a plan
for resolving any conflicts, suggested means for resolving conflict,
and process for notifying the communities of any changes in the
operations.
The measures described here and required in Sec. 18.137 through
Sec. 18.140, Mitigation, Monitoring, Reporting Requirements, and
Measures to Reduce Impacts to Subsistence Users, are those determined
to achieve the least practicable adverse impact to northern sea otters
and their availability for subsistence use. These mitigation measures
were evaluated against a suite of possible alternatives to determine
whether they would effect the least practicable adverse impact on the
species, their habitat, and the availability of the species for
subsistence uses.
Alternative mitigation measures were evaluated but ultimately
rejected as either not feasible, not practicable, not likely to be
implemented effectively, or no more likely to be successful in reducing
the impacts of the applicant's project. We considered requiring work to
be paused or stopped to prevent exposure of northern sea otters to
levels of noise exceeding a 160-dB Level B take threshold. The
distances to the 160-dB sound isopleths for several of the specified
activities are greater than 1 km (0.6 mi). Avoiding all northern sea
otters within these distances would require work to shut down or power
down for prolonged and repeated periods, which the applicant has
determined would incapacitate the project. Therefore, this is not a
practicable mitigation measure.
The Service considered alternative mitigation measures based on
observing and interpreting northern sea otter behaviors for preventing
Level B harassment. Presently, mitigation protocols use sound exposure
to predict behavioral responses rather than observing behavior
directly. While direct observation of injury or the disruption of a
behavioral pattern is the definitive criteria for identifying take once
it has occurred, at present there is insufficient data to develop
observation-based criteria for preventing harassment. Thus, monitoring
of behavioral responses is useful for identifying take after it occurs,
but not for preventing or mitigating it. As such, effectiveness of
monitoring protocols based on behavior cannot be ascertained.
Therefore, behavior-based mitigation was not a feasible alternative.
We considered requiring the use of alternative technologies such as
marine vibroseis to reduce or eliminate the
[[Page 37729]]
need for seismic airguns. Hilcorp and Harvest have requested takes of
marine mammals incidental to the seismic survey operations described in
the petition, which identified airgun arrays as the preferred data
acquisition tool. It would be inappropriate for the Service to require
the applicant to change the specified activity unless it was necessary
to make the findings established for issuance of incidental take under
the MMPA or necessary for achieving the least practicable adverse
impact to the marine mammal stock. Currently, no alternative technology
scaled for industrial use is reliable enough to meet the environmental
challenges of operating in Cook Inlet. Many prototypes are currently in
development and may ultimately become important for achieving the least
practicable level of effect on marine mammals, but none of these
technologies are currently practicable for use on a large scale in Cook
Inlet.
The option of designating seasonal exclusion areas within the
specified geographic area was considered. However, no activities are
planned in areas of Cook Inlet known to provide important habitat.
Kachemak Bay, Kamishak Bay, and the designated critical habitat along
the western shoreline of LCI and MCI are known areas of important
habitat, but have not been identified as the target location of any
planned activity in this rule. There is some information that suggests
that the east coast of Cook Inlet along the Kenai Peninsula may be used
seasonally by sea otters in late summer (BlueCrest 2013). Restrictions
on seismic survey operations in this area during this time period might
reduce the probability of disturbance of sea otters. However, there is
currently insufficient information to support a seasonal restriction in
eastern Cook Inlet. Little is known about the extent or duration of the
use of the area by sea otters or what life-history functions the area
supports. The benefit such a designation might offer is entirely
unknown and, until additional information is available, remains
speculative.
Compensatory mitigation was considered. Some environmental laws
allow compensatory mitigation, such as habitat restoration projects, to
be used by the applicant to offset effects of the project activities
that cannot otherwise be avoided. The Service is issuing an
authorization for incidental take of sea otters under the MMPA. The
MMPA requires that impacts be reduced to the least practicable level,
but does not require offsets. The Service must consider the
practicability of implementation of measures to reduce impacts, as well
as proven or likely effectiveness of those measures. The impacts to sea
otters and their habitat in Cook Inlet will be primarily acoustic and
temporary in nature. We are not currently aware of literature
demonstrating the effectiveness of habitat restoration for mitigating
the effects of underwater noise. Additionally, we are not aware of any
practicable habitat improvement projects in Cook Inlet that would have
demonstrable benefits for the affected stocks.
In order to issue an LOA for an activity, section 101(a)(5)(A) of
the MMPA states that the Service must set forth ``requirements
pertaining to the monitoring and reporting of such taking.'' The
Service's implementing regulations at Sec. 18.27(d)(vii) stipulate
that requests for authorizations must include the suggested means of
accomplishing the necessary monitoring and reporting. Effective
reporting is critical to compliance as well as ensuring that the most
value is obtained from the required monitoring. The applicant will
employ PSOs to conduct visual project monitoring. SSV monitoring will
be conducted to document sound levels produced by the work. During 2D
and 3D seismic surveys, Hilcorp and Harvest have agreed to conduct
aerial overflights for avoidance of other marine mammal species, which
will improve monitoring of sea otters. Additional monitoring and
reporting requirements are at Sec. 18.138 Monitoring and Sec. 18.139
Reporting requirements.
Alternative monitoring measures were considered, but they were not
incorporated in this rule. Passive acoustic monitoring is appropriate
for some species of marine mammals but is not indicated for sea otters,
which are not known to vocalize extensively underwater. Visual
monitoring during all times of day and night was rejected because
limited visibility during periods of darkness would prevent the
detection of animals. Thermal monitoring or monitoring of sea otters
with unmanned aircraft systems (drones) has not yet been fully tested
and evaluated for use in Cook Inlet, but may prove useful in the
future. Requiring visual observation and PSO monitoring of 100 percent
of all spatial areas within the 160-dB ensonification area was also
considered, but for 2D and 3D seismic surveys in particular, this was
not expected to be achievable. We instead accounted for all sea otter
exposures to 160 dB or greater in our estimation of take, and we did
not reduce this number to attempt to account for some proportion of the
total that might be avoided when detected by PSO monitoring.
Estimated Incidental Take
This section provides the number of incidental takes estimated to
occur because of the planned activities. The number of takes were
analyzed to make the required small numbers and negligible impact
determinations.
Estimating Exposure Rates
The Service anticipates that incidental take of sea otters may
occur during the project activities in Cook Inlet. Noise, aircraft,
vessels, and human activities could temporarily interrupt feeding,
resting, and movement patterns. Elevated underwater noise levels from
seismic surveys may cause short-term, nonlethal, but biologically
significant changes in behavior that the Service considers harassment.
Pile-driving and other construction activities along the shoreline may
have similar effects and could cause behavioral disturbance leading to
take. Harassment (Level A or B) is the only type of take expected to
result from these activities; no lethal take is expected.
The number of animals affected will be determined by the
distribution of animals and their location in proximity to the project
work. Although we cannot predict the outcome of each encounter, it is
possible to consider the most likely reactions, given observed
responses of sea otters to various stimuli.
Sound exposure criteria provide the best available proxy for
estimation of exposure to harassment. The behavioral response of sea
otters to shoreline construction and vessel activities is related to
the distance between the activity and the animals. Underwater sound is
generated in tandem with other airborne visual, olfactory, or auditory
signals from the specified activities, and travels much farther.
Therefore, estimating exposure to underwater sound can be used to
estimate the take from project activities.
No separate exposure evaluation was done for activities that do not
generate underwater sound. Nearly all of the planned activities that
may disturb sea otters will occur simultaneously with in-water
activities that do generate sound. For example, operation of heavy
equipment along the shoreline will facilitate underwater pile driving.
The otters affected by the equipment operations are the same as those
affected by the pile driving. Sound exposure and behavioral
disturbances are accumulated over a 24-hour period, resulting in
estimation of one exposure from all in-water sources rather than one
each from equipment operations
[[Page 37730]]
and pile-driving noise. Aircraft support activities will be conducted
without a corresponding underwater sound component, but no take is
expected from this source of disturbance; see ``Airborne Sounds.''
To estimate the exposure of sea otters to take, we first calculated
the number of otters in Cook Inlet that occur within the project area.
The number of otters was calculated from density multiplied by project
area. Density was estimated according to region in Cook Inlet.
Density data for Kamishak and the East side of Cook Inlet along the
shore of the Kenai Peninsula was derived from aerial surveys conducted
in May 2017 (Garlich-Miller et al. 2018). Surveys were not conducted
for central Cook Inlet in 2017, and the 2017 surveys for western Cook
Inlet north of Kamishak did not yield useful results. Therefore, the
density for those regions was derived from the 2002 surveys conducted
by Bodkin et al. (2003) and corrected for population growth
proportional to the growth rate of Cook Inlet as a whole, as determined
from comparison of the 2002 and 2017 surveys. Density values (in otters
per km\2\) were 1.7 in East Cook Inlet (excluding Kachemak Bay and the
outer Coast of Kenai Peninsula south and east of Seldovia), 3.53 in
Kamishak Bay, and 0.026 in West and Central Cook Inlet. There are no
density data for sea otters in the MCI region north of approximately
60[deg]14' N (the latitude of Clam Gulch), and otters are uncommon
north of about 60[deg]24' N. Therefore, densities north of Clam Gulch
were conservatively assumed to equal the 2002 mid-Cook Inlet survey
region density of 0.01 per km\2\ from Bodkin et al. (2003).
The geographic area of activity covers approximately 11,084 km\2\
(4,280 mi\2\) in Cook Inlet. Of this area, 1,572 km\2\ (607 mi\2\) is
in East Cook Inlet, 725 km\2\ (280 mi\2\) in Kamishak Bay, 4,341 km\2\
(1,676 mi\2\) in West and Central Cook Inlet, and 4,445 km\2\ (1,716
mi\2\) in Cook Inlet north of the normal range of sea otters. The total
number of otters within the project area was calculated to be 5,389
otters ((1,572 x 1.7) + (725 x 3.53) + (4,341 x 0.026) + (4,445 x 0.01)
[ap] 5,389).
Not all otters in the project area will be exposed to noise levels
capable of causing take from project activities. Many activities
associated with oil and gas exploration, development, production, and
transportation may result in underwater sounds that do not meet Levels
A and B acoustic harassment criteria. The acoustic characteristics of
the different project activities are described in table 3. Only those
specific activities with the likelihood of meeting the acoustic
exposure criteria and occurring in the normal range of sea otters were
evaluated for estimation of potential Levels A and B harassment.
Specifically, Hilcorp and Harvest's activities include 2D and 3D
seismic surveys, vibratory driving of sheet piles at the Iniskin
Peninsula causeway in Chinitna Bay, sub-bottom profilers used in high-
and low-resolution geohazard surveys, drive-pipe installation, vertical
seismic profiling, plug-and-abandon activities, and use of water jets
during routine maintenance. AGDC's activities include pile driving and
anchor handling.
The number of exposures to underwater sound levels capable of
causing take by Level A harassment from specific project elements was
estimated using the thresholds recommended by NMFS (2018a,b) for
otariid pinnipeds (232 dB peak and 203 dB SELcum). For Level
B harassment we used a 160-dB threshold. We multiplied the estimated
area of ensonification (km\2\), by the density of sea otters in that
area (number (#) of otters per km\2\) to estimate the number of otters
in the ensonified area. This value was then multiplied by the maximum
duration of the activity (# of days) over the course of the 5-year
regulatory period to get the total number of exposures to sound above
the thresholds for take.
Predicting Behavioral Response Rates
Although we cannot predict the outcome of each encounter between a
sea otter and the equipment and vessels used for the planned
activities, it is possible to consider the most likely reactions. Sea
otters do not appear highly reactive to underwater sounds, but the
presence of vessels may elicit stronger behavioral responses (see
Responses to Activities). Whether an individual animal responds
behaviorally to the presence of vessels and equipment is dependent upon
several variables, including the activity of the animal prior to
stimulus, whether the animal is habituated to similar disturbances,
whether the animal is in a state of heightened awareness due to recent
disturbances or the presence of predators, group size, the presence of
pups, and the temperament of the individual animals. We assumed all
animals exposed to underwater sound levels that meet the acoustic
exposure criteria shown in table 5 would experience Level A or Level B
take.
Calculating Take
The total take of sea otters from these oil and gas activities in
Cook Inlet was estimated by calculating the number of otters in the
ensonified area during the full duration (the maximum number of days)
of each project activity. After publication of the proposed ITR in the
Federal Register, the applicant provided updates and minor
modifications to their project plans. Changes included an increase in
the 3D seismic survey line length from 74 km (46 mi) to 127 km (79 mi),
an adjustment to account for the proportion of line length actively
surveyed with the airgun array each day, use of a boomer rather than
chirper sub-bottom profiler, and changes to the total duration (number
of days) of pile driving and vertical seismic profiling in TB and LCI.
The changes are reflected in the analysis presented here. Details of
the project activities and calculations of take are included in the
applicant's updated petition (June 2019) available at
www.regulations.gov under docket number FWS-R7-ES-2019-0012. Methods
used for calculating take did not change, but the resulting estimates
have been updated. The total take increased from 1,666 to 1,687.
Distances to Thresholds
To calculate the ensonified area, we first estimated the distances
that underwater sound will travel before attenuating to levels below
thresholds for take by Level A and Level B harassment. The distances to
the Level A thresholds were calculated using the NMFS Acoustical
Guidance Spreadsheets (NMFS 2018b) using thresholds for otariid
pinnipeds as a proxy for sea otters. Distances to the 160-dB Level B
threshold were calculated using a practical spreading transmission loss
model (15 LogR). The only exceptions to the use of the practical
spreading model were made when data was available from a site-specific
sound source verification of substantially similar equipment used and
powered in a similar manner to that proposed by the applicant.
Model estimates incorporated operational and environmental
parameters for each activity. For example, sound levels at the source
are shown in table 3, and characteristics of the sound produced are
shown in table 6. Weighting factor adjustments were used for SEL (sound
exposure level) calculations based on NMFS Technical Guidance (2018b).
Operational parameters were estimated from the updated description of
activities.
The distances to the modelled Level A and Level B thresholds are
shown in table 7. Each estimate represents the radial distance away
from the sound source within which a sea otter exposed to the sound of
the activity is expected
[[Page 37731]]
to experience take by Level A or Level B harassment.
Table 6--Assumptions Used in Calculating Distances to Level A and Level B Thresholds
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Activity Type of source Source level \1\ WFA \2\ Source velocity Pulse duration Repetition rate Duration per day
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
2D/3D seismic.................... Mobile impulsive.... 217 @100 m (185 dBSEL @100 m). 1 kHz............. 2.05 m/s.......... N/A............... every 6 s............. 3D: 10 hrs/day.
2D: 2 hrs/day.
Sub bottom profiler.............. Mobile impulsive.... 212 @1 m...................... 4 kHz............. 2.05 m/s.......... 0.02 s............ every 0.30 s.......... N/A.
Impact pile driving.............. Stationary impulsive https://www.regulations.gov.
Regulatory Planning and Review
Executive Order 12866 provides that the Office of Information and
Regulatory Affairs (OIRA) in the Office of Management and Budget (OMB)
will review all significant rules for a determination of significance.
OMB has designated this rule as not significant.
Executive Order 13563 reaffirms the principles of Executive Order
12866 while calling for improvements in the nation's regulatory system
to promote predictability, to reduce uncertainty, and to use the best,
most innovative, and least burdensome tools for achieving regulatory
ends. The executive order directs agencies to consider regulatory
approaches that reduce burdens and maintain flexibility
[[Page 37744]]
and freedom of choice for the public where these approaches are
relevant, feasible, and consistent with regulatory objectives.
Executive Order 13563 emphasizes further that regulations must be based
on the best available science and that the rulemaking process must
allow for public participation and an open exchange of ideas. We have
developed this rule in a manner consistent with these requirements.
OIRA bases its determination of significance upon the following
four criteria: (a) Whether the rule will have an annual effect of $100
million or more on the economy or adversely affect an economic sector,
productivity, jobs, the environment, or other units of the government;
(b) Whether the rule will create inconsistencies with other Federal
agencies' actions; (c) Whether the rule will materially affect
entitlements, grants, user fees, loan programs, or the rights and
obligations of their recipients; (d) Whether the rule raises novel
legal or policy issues.
Expenses will be related to, but not necessarily limited to: The
development of applications for LOAs; monitoring, recordkeeping, and
reporting activities conducted during oil and gas operations;
development of activity- and species-specific marine mammal monitoring
and mitigation plans; and coordination with Alaska Natives to minimize
effects of operations on subsistence hunting. Realistically, costs of
compliance with this rule are minimal in comparison to those related to
actual oil and gas exploration, development, production, and transport
operations. The actual costs to develop the petition for promulgation
of regulations and LOA requests probably do not exceed $200,000 per
year, short of the ``major rule'' threshold that would require
preparation of a regulatory impact analysis. As is presently the case,
profits will accrue to the applicant; royalties and taxes will accrue
to the Government; and the rule will have little or no impact on
decisions by the applicant to relinquish tracts and write off bonus
payments.
Small Business Regulatory Enforcement Fairness Act
We have determined that this rule is not a major rule under 5
U.S.C. 804(2), the Small Business Regulatory Enforcement Fairness Act.
The rule is also not likely to result in a major increase in costs or
prices for consumers, individual industries, or government agencies or
have significant adverse effects on competition, employment,
productivity, innovation, or on the ability of United States-based
enterprises to compete with foreign-based enterprises in domestic or
export markets.
Regulatory Flexibility Act
We have determined that this rule will not have a significant
economic effect on a substantial number of small entities under the
Regulatory Flexibility Act (5 U.S.C. 601 et seq.). Hilcorp, Harvest,
AGDC, and their contractors conducting exploration, development,
production, and transportation of oil and gas in Cook Inlet, Alaska,
are the only entities subject to this ITR. Therefore, neither a
Regulatory Flexibility Analysis nor a Small Entity Compliance Guide is
required.
Takings Implications
This rule does not have takings implications under Executive Order
12630 because it authorizes the nonlethal, incidental, but not
intentional, take of sea otters by oil and gas industry companies and,
thereby, exempts these companies from civil and criminal liability as
long as they operate in compliance with the terms of their LOAs.
Therefore, a takings implications assessment is not required.
Federalism Effects
This rule does not contain policies with Federalism implications
sufficient to warrant preparation of a Federalism Assessment under
Executive Order 13132. The MMPA gives the Service the authority and
responsibility to protect sea otters.
Unfunded Mandates Reform Act
In accordance with the Unfunded Mandates Reform Act (2 U.S.C. 1501
et seq.), this rule will not ``significantly or uniquely'' affect small
governments. A Small Government Agency Plan is not required. The
Service has determined and certifies pursuant to the Unfunded Mandates
Reform Act that this rulemaking will not impose a cost of $100 million
or more in any given year on local or State governments or private
entities. This rule will not produce a Federal mandate of $100 million
or greater in any year, i.e., it is not a ``significant regulatory
action'' under the Unfunded Mandates Reform Act.
Government-to-Government Relationship With Native American Tribal
Governments
It is our responsibility to communicate and work directly on a
Government-to-Government basis with federally recognized Alaska Native
tribes and corporations in developing programs for healthy ecosystems.
We seek their full and meaningful participation in evaluating and
addressing conservation concerns for protected species. It is our goal
to remain sensitive to Alaska Native culture, and to make information
available to Alaska Natives. Our efforts are guided by the following
policies and directives: (1) The Native American Policy of the Service
(January 20, 2016); (2) the Alaska Native Relations Policy (currently
in draft form); (3) Executive Order 13175 (January 9, 2000); (4)
Department of the Interior Secretarial Orders 3206 (June 5, 1997), 3225
(January 19, 2001), 3317 (December 1, 2011), and 3342 (October 21,
2016); (5) the Alaska Government-to-Government Policy (a departmental
memorandum issued January 18, 2001); and (6) the Department of the
Interior's policies on consultation with Alaska Native tribes and
organizations.
We have evaluated possible effects of the specified activities on
federally recognized Alaska Native Tribes and corporations. Through the
ITR process identified in the MMPA, the applicant has presented a
communication process, culminating in a POC if needed, with the Native
organizations and communities most likely to be affected by their work.
The applicant has engaged these groups in informational communications.
We invited continued discussion about the proposed ITR.
We received a request for Government-to-Government consultation on
this ITR from the Chickaloon Village Traditional Council (CVTC). When
the CVTC and the Service were not able to schedule a time and place
suitable to both parties to conduct the consultation, the CVTC chose to
provide written comments to the Service expressing their views on the
ITR. We have responded to their comments under Summary of and Response
to Comments and Recommendations and will continue to engage with CVTC
to determine whether further consultation is desired.
Civil Justice Reform
The Departmental Solicitor's Office has determined that this
regulation does not unduly burden the judicial system and meets the
applicable standards provided in sections 3(a) and 3(b)(2) of Executive
Order 12988.
Paperwork Reduction Act
This rule includes a revision to an existing information
collection. All information collections require approval under the
Paperwork Reduction Act of 1995 (44 U.S.C. 3501 et seq.). We may not
conduct or sponsor, and you are not required to respond to, a
collection of information unless it displays a currently valid OMB
control number.
[[Page 37745]]
The OMB previously reviewed and approved the information collection
requirements associated with incidental take of marine mammals in the
Beaufort and Chukchi Seas and assigned OMB Control Number 1018-0070
(expires July 31, 2020).
The revised requirements reporting and/or recordkeeping
requirements identified below were approved by OMB:
(1) Remove references to 50 CFR 18 subpart I (expired); and
(2) Add references to 50 CFR 18 subpart K.
Title of Collection: Incidental Take of Marine Mammals During
Specified Activities, 50 CFR 18.27 and 50 CFR 18, Subparts J and K.
OMB Control Number: 1018-0070.
Form Numbers: None.
Type of Review: Revision of a currently approved collection.
Respondents/Affected Public: Oil and gas industry representatives,
including applicants for ITRs and LOAs, operations managers, and
environmental compliance personnel.
Total Estimated Number of Annual Respondents: 84.
Total Estimated Number of Annual Responses: 356.
Estimated Completion Time per Response: Varies from 1.5 hours to
150 hours, depending on activity.
Total Estimated Number of Annual Burden Hours: 1,800.
Respondent's Obligation: Required to obtain or retain a benefit.
Frequency of Collection: On occasion.
Total Estimated Annual Non-hour Burden Cost: $200,000.
You may send comments on any aspect of this information collection
to the Service Information Collection Clearance Officer, U.S. Fish and
Wildlife Service, 5275 Leesburg Pike, MS: JAO/1N, Falls Church, VA
22041-3803 (mail); or [email protected] (email). Please reference OMB
Control Number 1018-BD63/0070 in the subject line of your comments
Energy Effects
Executive Order 13211 requires agencies to prepare Statements of
Energy Effects when undertaking certain actions. This rule provides
exceptions from the taking prohibitions of the MMPA for entities
engaged in the exploration of oil and gas in Cook Inlet, Alaska. By
providing certainty regarding compliance with the MMPA, this rule will
have a positive effect on the oil and gas industry and its activities.
Although the rule requires an applicant to take a number of actions,
these actions have been undertaken as part of oil and gas industry
operations for many years as part of similar past regulations in
Alaska. Therefore, this rule is not expected to significantly affect
energy supplies, distribution, or use and does not constitute a
significant energy action. No Statement of Energy Effects is required.
References
For a list of the references cited in this rule, see Docket No.
FWS-R7-ES-2019-0012, available at https://www.regulations.gov.
List of Subjects in 50 CFR Part 18
Administrative practice and procedure, Alaska, Imports, Indians,
Marine mammals, Oil and gas exploration, Reporting and recordkeeping
requirements, Transportation.
Regulation Promulgation
For the reasons set forth in the preamble, the Service amends part
18, subchapter B of chapter 1, title 50 of the Code of Federal
Regulations as set forth below.
PART 18--MARINE MAMMALS
0
1. The authority citation of 50 CFR part 18 continues to read as
follows:
Authority: 16 U.S.C. 1361 et seq.
0
2. Add subpart K to read as follows:
Subpart K--Nonlethal Taking of Marine Mammals Incidental to Oil and Gas
Activities in Cook Inlet, Alaska
Sec.
18.130 Specified activities covered by this subpart.
18.131 Specified geographic region where this subpart applies.
18.132 Dates this subpart is in effect.
18.133 Authorized take allowed under a Letter of Authorization
(LOA).
18.134 Procedure to obtain a Letter of Authorization (LOA).
18.135 How the Service will evaluate a request for a Letter of
Authorization (LOA).
18.136 Prohibited take under a Letter of Authorization (LOA).
18.137 Mitigation.
18.138 Monitoring.
18.139 Reporting requirements.
18.140 Measures to reduce impacts to subsistence users.
18.141 Information collection requirements.
Subpart K--Nonlethal Taking of Marine Mammals Incidental to Oil and
Gas Activities in Cook Inlet, Alaska
Sec. 18.130 Specified activities covered by this subpart.
Regulations in this subpart apply to the nonlethal incidental, but
not intentional, take, as defined in 50 CFR 18.3 and under the Marine
Mammal Protection Act (16 U.S.C. 1362), of small numbers of northern
sea otters (Enhydra lutris kenyoni; hereafter ``otter,'' ``otters,'' or
``sea otters'') by Hilcorp Alaska, LLC, Harvest Alaska, LLC, and the
Alaska Gasline Development Corporation while engaged in activities
associated with or in support of oil and gas exploration, development,
production, and transportation in Cook Inlet, Alaska.
Sec. 18.131 Specified geographic region where this subpart applies.
(a) The specified geographic region is Cook Inlet, Alaska, south of
a line from the Susitna River Delta to Point Possession (approximately
61[deg]15'54'' N, 150[deg]41'07'' W, to 61[deg]02'19'' N,
150[deg]23'48'' W, WGS 1984) and north of a line from Rocky Cove to
Coal Cove (approximately 59[deg]25'56'' N, 153[deg]44'25'' W and
59[deg]23'48'' N, 151[deg]54'28'' W, WGS 1984), excluding Ursus Cove,
Iniskin Bay, Iliamna Bay, and Tuxedni Bay.
(b) The geographic area of this incidental take regulation (ITR)
includes all Alaska State waters and Outer Continental Shelf Federal
waters within this area as well as all adjacent rivers, estuaries, and
coastal lands where sea otters may occur, except for those areas
explicitly excluded in paragraph (a) of this section.
(c) Map of the Cook Inlet ITR region follows:
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[GRAPHIC] [TIFF OMITTED] TR01AU19.000
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Sec. 18.132 Dates this subpart is in effect.
Regulations in this subpart are effective from August 1, 2019, to
August 1, 2024.
Sec. 18.133 Authorized take allowed under a Letter of Authorization
(LOA).
(a) To incidentally take marine mammals pursuant to the regulations
in this subpart,, Hilcorp Alaska, LLC, Harvest Alaska, LLC, or the
Alaska Gasline Development Corporation (hereafter ``the applicant'')
must apply for and obtain an LOA in accordance with Sec. Sec. 18.27(f)
and 18.134. The applicant is a U.S. citizen as defined in Sec.
18.27(c).
(b) An LOA allows for the nonlethal, incidental, but not
intentional take by harassment of sea otters during activities
specified in Sec. 18.130 within the Cook Inlet ITR region described in
Sec. 18.131.
(c) Each LOA will set forth:
(1) Permissible methods of incidental take;
(2) Means of effecting the least practicable adverse impact (i.e.,
mitigation) on the species, its habitat, and the availability of the
species for subsistence uses; and
(3) Requirements for monitoring and reporting.
(d) Issuance of the LOA(s) must be based on a determination that
the level of take will be consistent with the findings made for the
total allowable take under these regulations in this subpart.
Sec. 18.134 Procedure to obtain a Letter of Authorization (LOA).
(a) The applicant must submit the request for authorization to the
U.S. Fish and Wildlife Service (Service) Alaska Region Marine Mammals
Management Office (MMM), MS 341, 1011 East Tudor Road, Anchorage,
Alaska, 99503, at least 90 days prior to the start of the proposed
activity.
(b) The request for an LOA must comply with the requirements set
forth in Sec. Sec. 18.137 through 18.139 and must include the
following information:
(1) A plan of operations that describes in detail the proposed
activity (type of project, methods, and types and numbers of equipment
and personnel, etc.), the dates and duration of the activity, and the
specific locations of and areas affected by the activity. Changes to
the proposed project without prior authorization may invalidate an LOA.
(2) A site-specific marine mammal monitoring and mitigation plan to
monitor and mitigate the effects of the activity on sea otters.
(3) An assessment of potential effects of the proposed activity on
subsistence hunting of sea otters.
(i) The applicant must communicate with potentially affected
subsistence communities along the Cook Inlet coast and appropriate
subsistence user organizations to discuss the location, timing, and
methods of proposed activities and identify any potential conflicts
with subsistence hunting activities.
(ii) The applicant must specifically inquire of relevant
communities and organizations if the proposed activity will interfere
with the availability of sea otters for the subsistence use of those
groups.
(iii) The applicant must include documentation of consultations
with potentially affected user groups.
[[Page 37747]]
Documentation must include a list of persons contacted, a summary of
input received, any concerns identified by community members and hunter
organizations, and the applicant's responses to identified concerns.
(iv) If any concerns regarding effects of the activity on sea otter
subsistence harvest are identified, the applicant will provide to the
Service a Plan of Cooperation (POC) with specific steps for addressing
those concerns, including a schedule for ongoing community engagement
and suggested measures that will be implemented to mitigate any
potential conflicts with subsistence hunting.
Sec. 18.135 How the Service will evaluate a request for a Letter of
Authorization (LOA).
(a) The Service will evaluate each request for an LOA to determine
if the proposed activity is consistent with the analysis and findings
made for these regulations. Depending on the results of the evaluation,
we may grant the authorization, add further conditions, or deny the
authorization.
(b) Once issued, the Service may withdraw or suspend an LOA if the
project activity is modified in a way that undermines the results of
the previous evaluation, if the conditions of the regulations in this
subpart are not being substantially complied with, or if the taking
allowed is or may be having more than a negligible impact on the
affected stock of sea otters or an unmitigable adverse impact on the
availability of sea otters for subsistence uses.
(c) The Service will make decisions concerning withdrawals of an
LOA, either on an individual or class basis, only after notice and
opportunity for public comment in accordance with Sec. 18.27(f)(5).
The requirement for notice and public comment will not apply should we
determine that an emergency exists that poses a significant risk to the
well-being of the species or stocks of sea otters.
Sec. 18.136 Prohibited take under a Letter of Authorization (LOA).
(a) Except as otherwise provided in this subpart, prohibited taking
is described in Sec. 18.11 as well as: Intentional take, lethal
incidental take of sea otters, and any take that fails to comply with
this subpart or with the terms and conditions of an LOA.
(b) If project activities cause unauthorized take, the applicant
must take the following actions:
(1) Cease activities immediately (or reduce activities to the
minimum level necessary to maintain safety) and report the details of
the incident to the Service MMM within 48 hours; and
(2) Suspend further activities until the Service has reviewed the
circumstances, determined whether additional mitigation measures are
necessary to avoid further unauthorized taking, and notified the
applicant that it may resume project activities.
Sec. 18.137 Mitigation.
(a) Mitigation measures for all LOAs. The applicant, including all
personnel operating under the applicant's authority (or ``operators,''
including contractors, subcontractors, and representatives) must
undertake the following activities to avoid and minimize take of sea
otters by harassment.
(1) Implement policies and procedures to avoid interactions with
and minimize to the greatest extent practicable adverse impacts on sea
otters, their habitat, and the availability of these marine mammals for
subsistence uses.
(2) Develop avoidance and minimization policies and procedures, in
cooperation with the Service, that include temporal or spatial activity
restrictions to be used in response to the presence of sea otters
engaged in a biologically significant activity (e.g., resting, feeding,
hauling out, mating, or nursing).
(3) Cooperate with the Service's MMM Office and other designated
Federal, State, and local agencies to monitor and mitigate the impacts
of oil and gas industry activities on sea otters.
(4) Allow Service personnel or the Service's designated
representative to board project vessels or visit project work sites for
the purpose of monitoring impacts to sea otters and subsistence uses of
sea otters at any time throughout project activities so long as it is
safe to do so.
(5) Designate trained and qualified protected species observers
(PSOs) to monitor for the presence of sea otters, initiate mitigation
measures, and monitor, record, and report the effects of the activities
on sea otters. The applicant is responsible for providing training to
PSOs to carry out mitigation and monitoring.
(6) Have an approved mitigation and monitoring plan on file with
the Service MMM and onsite that includes the following information:
(i) The type of activity and where and when the activity will occur
(i.e., a summary of the plan of operation);
(ii) Personnel training policies, procedures, and materials;
(iii) Site-specific sea otter interaction risk evaluation and
mitigation measures;
(iv) Sea otter avoidance and encounter procedures; and
(v) Sea otter observation and reporting procedures.
(7) Contact affected subsistence communities and hunter
organizations to identify any potential conflicts that may be caused by
the proposed activities and provide the Service documentation of
communications as described in Sec. 18.134.
(b) Mitigation measures for in-water noise-generating work. The
applicant must carry out the following measures:
(1) Mitigation zones. Establish mitigation zones for project
activities that generate underwater sound levels >=160 decibels (dB)
between 125 hertz (Hz) and 38 kilohertz (kHz) (hereafter ``noise-
generating work'').
(i) All dB levels are referenced to 1 [micro]Pa for underwater
sound. All dB levels herein are dBRMS unless otherwise
noted; dBRMS refers to the root-mean-squared dB level, the
square root of the average of the squared sound pressure level,
typically measured over 1 second.
(ii) Mitigation zones must include all in-water areas where work-
related sound received by sea otters will match the levels and
frequencies in paragraph (b)(1) of this section. Mitigation zones will
be designated as follows:
(A) An Exclusion Zone (EZ) will be established throughout all areas
where sea otters may be exposed to sound levels capable of causing
Level A take as shown in the table in paragraph (b)(1)(iii) of this
section.
(B) The Safety Zone (SZ) is an area larger than the EZ and will
include all areas within which sea otters may be exposed to noise
levels that will likely result in Level B take as shown in the table in
paragraph (b)(1)(iii) of this section.
(C) Both the EZ and SZ will be centered on the sound source. The
method of estimation and minimum radius of each zone will be specified
in any LOA issued under Sec. 18.135 and will be based on onsite sound
source verification (SSV), if available, or the best available science.
(D) Onsite SSV testing will be conducted prior to two-dimensional
(2D) and three-dimensional (3D) seismic surveys.
(E) Seismic surveys (2D and 3D) must be conducted using equipment
that generates the lowest practicable levels of underwater sound within
the range of frequencies audible to sea otters.
(iii) Summary of acoustic exposure thresholds for take of sea
otters from underwater sound in the frequency range 125 Hz-38 kHz:
[[Page 37748]]
Table 1 to Sec. 18.137(b)(1)(iii)
----------------------------------------------------------------------------------------------------------------
Injury (Level A) threshold \1\ Disturbance (Level B) threshold
Marine mammals -------------------------------------------------------------------------------
Impulsive Non-impulsive All
----------------------------------------------------------------------------------------------------------------
Sea otters...................... 232 dB peak; 203 dB 219 dB SELCUM...... 160 dBRMS.
SELCUM.
----------------------------------------------------------------------------------------------------------------
\1\ Based on acoustic criteria for otariid pinnipeds from the National Marine Fisheries Service. Sound source
types are separated into impulsive (e.g., seismic, pipe driving, sub-bottom profiler) and non-impulsive
(drilling, water jet) and require estimation of the distance to the peak received sound pressure level (peak)
and 24-hr cumulative sound exposure level (SELCUM).
(2) Monitoring. Designate trained and qualified PSOs or
``observers'' to monitor for the presence of sea otters in mitigation
zones, initiate mitigation measures, and record and report the effects
of project work on otters for all noise-generating work.
(3) Mitigation measures for sea otters in mitigation zones. The
following actions will be taken in response to otters in mitigation
zones:
(i) Sea otters that are under no visible distress within the SZ
must be monitored continuously. Power down, shut down, or maneuver away
from the sea otter if practicable to reduce sound received by the
animal. Maintain 100-m (301-ft) separation distance whenever possible.
Exposures in this zone are counted as one Level B take per animal per
day.
(ii) When sea otters are observed within or approaching the EZ,
noise-generating work as defined in paragraph (b)(1) of this section
must be immediately shut down or powered down to reduce the size of the
zone sufficiently to exclude the animal from the zone. Vessel speed or
course may be altered to achieve the same task. Exposures in this zone
are counted as one Level A take per animal per day.
(iii) When sea otters are observed in visible distress (for
example, vocalizing, repeatedly spy-hopping, or fleeing), noise-
generating work as defined in paragraph (b)(1) of this section must be
immediately shut down or powered down to reduce the size of the zone
sufficiently to exclude the animal from the zone.
(iv) Following a shutdown, the noise-generating activity will not
resume until the sea otter has cleared the EZ. The animal will be
considered to have cleared the EZ if it is visually observed to have
left the EZ or has not been seen within the EZ for 30 minutes or
longer.
(4) Ramp-up procedures. Prior to noise-generating work, a ``ramp-
up'' procedure must be used to increase the levels of underwater sound
from noise-generating work at a gradual rate.
(i) Seismic surveys: A ramp-up will be used at the initial start of
airgun operations and prior to restarting after any period greater than
10 minutes without airgun operations, including a power-down or
shutdown event (described in paragraphs (b)(6) and (7) of this
section). During geophysical work, the number and total volume of
airguns will be increased incrementally until the full volume is
achieved. The rate of ramp-up will be no more than 6 dB per 5-minute
period. Ramp-up will begin with the smallest gun in the array that is
being used for all airgun array configurations. During the ramp-up, the
applicable mitigation zones (based on type of airgun and sound levels
produced) must be maintained. It will not be permissible to ramp up the
full array from a complete shutdown in thick fog or at other times when
the outer part of the EZ is not visible. Ramp-up of the airguns will
not be initiated if a sea otter is sighted within the EZ at any time.
(ii) Pile/pipe driving: A ramp-up of the hammering will precede
each day's pipe/pile driving activities or if pipe/pile driving has
ceased for more than 1 hour. The EZ will be determined clear of sea
otters 30 minutes prior to a ramp-up to ensure no sea otters are within
or entering the EZ. Initial hammering starts will not begin during
periods of poor visibility (e.g., night, fog, wind) when the entire EZ
is not visible. The ramp-up procedure for impact hammers involves
initially starting with three soft strikes at 40 percent energy,
followed by a 1-minute waiting period followed by two subsequent three-
strike sets. For vibratory hammers, initial noise generation will be
limited to 15 seconds at a reduced energy level, followed by a 1-minute
waiting period. This cycle will be repeated two additional times.
Monitoring will occur during all hammering sessions.
(iii) All activities: Any shutdown due to sea otters sighted within
the EZ must be followed by a 30-minute all-clear period and then a
standard full ramp-up. Any shutdown for other reasons resulting in the
cessation of the sound source for a period greater than 30 minutes must
also be followed by full ramp-up procedures. If otters are observed
during a ramp-up effort or prior to startup, a PSO must record the
observation and monitor the animal's position until it moves out of
visual range. Noise-generating work may commence if, after a full and
gradual effort to ramp up the underwater sound level, the otter is
outside of the EZ and does not show signs of visible distress (for
example, vocalizing, repeatedly spy-hopping, or fleeing).
(5) Startup procedures. (i) Visual monitoring must begin at least
30 minutes prior to, and continue throughout, ramp-up efforts.
(ii) Visual monitoring must continue during all noise-generating
work occurring in daylight hours.
(6) Power-down procedures. A power-down procedure involves reducing
the volume of underwater sound generated to prevent an otter from
entering the EZ.
(i) Whenever a sea otter is detected outside the EZ and, based on
its position and motion relative to the noise-generating work, appears
likely to enter the EZ but has not yet done so, operators may reduce
power to noise-generating equipment as an alternative to a shutdown.
(ii) Whenever a sea otter is detected in the SZ, an operator may
power down when practicable to reduce Level B take.
(iii) During a power-down of seismic work, the number of airguns in
use may be reduced, such that the EZ is reduced, making the sea otters
unlikely to enter the EZ. A mitigation airgun (airgun of small volume
such as the 10-in\3\ gun) will be operated continuously during a power-
down of seismic work.
(iv) After a power-down, noise-generating work will not resume
until the sea otter has cleared the applicable EZ. The animal will be
considered to have cleared the applicable zone if it is visually
observed to have left the EZ and has not been seen within the zone for
30 minutes.
(7) Shutdown procedure. A shutdown occurs when all noise-generating
work is suspended.
(i) Noise-generating work will be shut down completely if a sea
otter enters the EZ.
(ii) The shutdown procedure will be accomplished within several
seconds of the determination that a sea otter is either in or about to
enter the EZ or as
[[Page 37749]]
soon as practicable considering worker safety and equipment integrity.
(iii) Noise-generating work will not proceed until all sea otters
have cleared the EZ and the PSOs on duty are confident that no sea
otters remain within the EZ. An otter will be considered to have
cleared the EZ if it is visually observed to have left the EZ or has
not been seen within the zone for 30 minutes.
(iv) Visual monitoring must continue for 30 minutes after use of
the acoustic source ceases or the sun sets, whichever is later.
(8) Emergency shutdown. If observations are made or credible
reports are received that one or more sea otters are within the area of
noise-generating work and are indicating acute distress associated with
the work, such as any injury due to seismic noise or persistent
vocalizations indicating separation of mother from pup, the work will
be immediately shut down and the Service contacted. Work will not be
restarted until review and approval by the Service.
(9) To ensure the proposed activities remain consistent with the
estimated take of sea otters, operators may not conduct 3D seismic
surveys where doing so will generate underwater noise levels that are
likely to exceed acoustic exposure thresholds within areas of estimated
sea otter densities greater than 0.026 otters per km. Maps of the areas
will be provided to 3D seismic operators and may be adjusted based on
SSV results. This does not apply to 2D seismic surveys.
(c) Mitigation for all in-water construction and demolition
activity. (1) The applicant must implement a minimum EZ of a 10-m
radius around the in-water construction and demolition. If a sea otter
comes within or approaches the EZ, such operations must cease. A larger
EZ may be required for some activities, such as blasting, and will be
specified in the LOA.
(2) All work in intertidal areas shall be conducted during low tide
when the site is dewatered to the maximum extent practicable.
(3) The applicant must evaluate alternatives to pile-supported
facilities. If no practicable alternative exists, the applicant must
then evaluate the use of sound-attenuation devices such as pile caps
and cushions, bubble curtains, and dewatered cofferdams during
construction. The Service may require sound-attenuation devices or
alternatives to pile-supported designs.
(d) Measures for vessel-based activities. (1) Vessel operators must
take every precaution to avoid harassment of sea otters when a vessel
is operating near these animals.
(2) Vessels must remain at least 500 m from rafts of otters unless
safety is a factor.
(3) Vessels must reduce speed and maintain a distance of 100 m (328
ft) from all sea otters unless safety is a factor.
(4) Vessels must not be operated in such a way as to separate
members of a group of sea otters from other members of the group.
(5) When weather conditions require, such as when visibility drops,
vessels must adjust speed accordingly to avoid the likelihood of injury
to sea otters.
(6) Vessels in transit and support vessels must use established
navigation channels or commonly recognized vessel traffic corridors,
and must avoid alongshore travel in shallow water ([email protected].
(f) Injured, dead, or distressed sea otters that are not associated
with project activities (e.g., animals known to be from outside the
project area, previously wounded animals, or carcasses with moderate to
advanced decomposition or scavenger damage) must be reported to the
Service within 24 hours of the discovery to either the Service MMM (1-
800-362-5148, business hours); or the Alaska SeaLife Center in Seward
(1-888-774-7325, 24 hours a day); or both. Photographs, video, location
information, or any other available documentation shall be provided to
the Service.
(g) Operators must notify the Service upon project completion or
end of the work season.
Sec. 18.140 Measures to reduce impacts to subsistence users.
(a) Prior to conducting the work, the applicant will take the
following steps to reduce potential effects on subsistence harvest of
sea otters:
(1) Avoid work in areas of known sea otter subsistence harvest;
(2) Discuss the planned activities with subsistence stakeholders
including Cook Inlet villages, traditional councils, and the Cook Inlet
Regional Citizens Advisory Council;
(3) Identify and work to resolve concerns of stakeholders regarding
the project's effects on subsistence hunting of sea otters; and
(b) If any unresolved or ongoing concerns remain, develop a POC in
consultation with the Service and subsistence stakeholders to address
these concerns. The POC must include a schedule for ongoing community
engagement and specific measures for mitigating any potential conflicts
with subsistence hunting.
Sec. 18.141 Information collection requirements.
(a) We may not conduct or sponsor, and a person is not required to
respond to, a collection of information unless it displays a currently
valid Office of Management and Budget (OMB) control number. OMB has
approved the collection of information contained in this subpart and
assigned OMB control number 1018-0070. The applicant must respond to
this information collection request to obtain a benefit pursuant to
section 101(a)(5) of the Marine Mammal Protection Act. We will use the
information to:
(1) Evaluate the application and determine whether or not to issue
specific LOAs; and
(2) Monitor impacts of activities and effectiveness of mitigation
measures conducted under the LOAs.
(b) Comments regarding the burden estimate or any other aspect of
this requirement must be submitted to the Information Collection
Clearance Officer, U.S. Fish and Wildlife Service, at the address
listed in 50 CFR part 2.1.
Dated: July 18, 2019.
Karen Budd-Falen,
Deputy Solicitor for Parks and Wildlife, Exercising the Authority of
the Assistant Secretary for Fish and Wildlife and Parks.
[FR Doc. 2019-16279 Filed 7-26-19; 4:15 pm]
BILLING CODE 4333-15-P
