[Federal Register Volume 84, Number 245 (Friday, December 20, 2019)]
[Rules and Regulations]
[Pages 70274-70325]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2019-27049]
[[Page 70273]]
Vol. 84
Friday,
No. 245
December 20, 2019
Part II
Department of Commerce
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National Oceanic and Atmospheric Administration
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50 CFR Part 217
Taking and Importing Marine Mammals; Taking Marine Mammals Incidental
to Construction and Operation of the Liberty Drilling and Production
Island, Beaufort Sea, Alaska; Final Rule
Federal Register / Vol. 84, No. 245 / Friday, December 20, 2019 /
Rules and Regulations
[[Page 70274]]
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DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
50 CFR Part 217
[Docket No. 191210-0105]
RIN 0648-BI00
Taking and Importing Marine Mammals; Taking Marine Mammals
Incidental to Construction and Operation of the Liberty Drilling and
Production Island, Beaufort Sea, Alaska
AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and
Atmospheric Administration (NOAA), Commerce.
ACTION: Final rule; notification of issuance.
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SUMMARY: NMFS hereby issues regulations to govern the unintentional
taking of marine mammals incidental to construction and operation of
the Liberty Drilling and Production Island (LDPI) in the Beaufort Sea,
Alaska over the course of five years. These regulations, which allow
for the issuance of a Letter of Authorization for the incidental take
of marine mammals during the described activities and specified
timeframes, prescribe the permissible methods of taking and other means
of effecting the least practicable adverse impact on marine mammal
species or stocks and their habitat, as well as requirements pertaining
to the monitoring and reporting of such taking.
DATES: This rule is effective December 1, 2021 through November 30,
2026.
FOR FURTHER INFORMATION CONTACT: Jaclyn Daly, Office of Protected
Resources, NMFS, (301) 427-8401.
SUPPLEMENTARY INFORMATION:
Purpose and Need for Regulatory Action
NMFS received an application from Hilcorp requesting five-year
regulations and authorization to incidentally take multiple species of
marine mammals in Foggy Island Bay, Beaufort Sea, by Level A harassment
(non-serious injury) and Level B harassment (behavioral disturbance),
incidental to construction and operation of the LDPI and associated
infrastructure. Please see ``Background'' below for definitions of
harassment. In addition, a limited unintentional take involving the
mortality or serious injury of no more than two ringed seals (Phoca
hispida) would be authorized to occur during annual ice road
construction and maintenance. This final rule establishes a framework
under the authority of the Marine Mammal Protection Act (MMPA) (16
U.S.C. 1361 et seq.) to allow for the issuance of a Letter of
Authorization (LOA) for the take of marine mammals incidental to
Hilcorp's activities related to construction and operation of the LDPI.
Legal Authority for the Proposed Action
Section 101(a)(5)(A) of the MMPA (16 U.S.C. 1371(a)(5)(A)) directs
the Secretary of Commerce to allow, upon request, the incidental, but
not intentional taking of small numbers of marine mammals by U.S.
citizens who engage in a specified activity (other than commercial
fishing) within a specified geographical region for up to five years
if, after notice and public comment, the agency makes certain findings
and issues regulations that set forth permissible methods of taking
pursuant to that activity and other means of effecting the ``least
practicable adverse impact'' on the affected species or stocks and
their habitat (see the discussion below in the ``Mitigation'' section),
as well as monitoring and reporting requirements. Section 101(a)(5)(A)
of the MMPA and the implementing regulations at 50 CFR part 216,
subpart I, provide the legal basis for issuing this rule containing
five-year regulations, and for any subsequent Letters of Authorization
(LOAs). As directed by this legal authority, this rule contains
mitigation, monitoring, and reporting requirements.
Summary of Major Provisions Within the Final Rule
The following is a summary of the major provisions of this final
rule Hilcorp would be required to implement. These measures include:
Use of soft start during impact pile driving to allow
marine mammals the opportunity to leave the area prior to beginning
impact pile driving at full power;
Implementation of shutdowns of construction activities
under certain circumstances to minimize harassment, including injury;
Prohibition on all pile and pipe driving at the island
site and vessel movement outside the barrier islands during the fall
Cross Island bowhead whale hunt, and seasonal drilling restrictions to
minimize impacts to marine mammals and subsistence users;
Implementation of best management practices to avoid and
minimize ice seal and habitat disturbance during ice road construction,
maintenance, and use;
Use of marine mammal and acoustic monitoring to detect
marine mammals and verify predicted sound fields;
Coordination with subsistence users and adherence to a
Plan of Cooperation (POC); and
Limitation on vessel speeds and transit areas, where
appropriate.
Background
The MMPA prohibits the take of marine mammals, with certain
exceptions. Sections 101(a)(5)(A) and (D) of the MMPA (16 U.S.C. 1361
et seq.) direct the Secretary of Commerce (as delegated to NMFS) to
allow, upon request, the incidental, but not intentional, taking of
small numbers of marine mammals by U.S. citizens who engage in a
specified activity (other than commercial fishing) within a specified
geographical region if certain findings are made and either regulations
are issued or, if the taking is limited to harassment, a notice of a
proposed incidental take authorization is provided to the public for
review. Under the MMPA, ``take'' is defined as meaning to harass, hunt,
capture, or kill, or attempt to harass, hunt, capture, or kill any
marine mammal. ``Harassment'' is statutorily defined as any act of
pursuit, torment, or annoyance which has the potential to injure a
marine mammal or marine mammal stock in the wild (Level A harassment)
or 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 but which does not have the potential to injure a marine
mammal or marine mammal stock in the wild (Level B harassment).
Authorization for incidental takings shall be granted if NMFS finds
that the taking will have a negligible impact on the species or
stock(s) and will not have an unmitigable adverse impact on the
availability of the species or stock(s) for taking for subsistence uses
(where relevant). Further, NMFS must prescribe the permissible methods
of taking and other ``means of effecting the least practicable
[adverse] impact'' on the affected species or stocks and their habitat,
paying particular attention to rookeries, mating grounds, and areas of
similar significance, and on the availability of such species or stocks
for taking for certain subsistence uses (referred to in shorthand as
``mitigation''); and ensure that requirements pertaining to the
mitigation, monitoring, and reporting of such takings are set forth.
[[Page 70275]]
Summary of Request
On August 2, 2017, Hilcorp petitioned NMFS for rulemaking under
Section 101(a)(5)(A) of the MMPA to authorize the take of six species
of marine mammals incidental to construction and operation of the
proposed LDPI in Foggy Island Bay, Alaska. On April 26, 2018, Hilcorp
submitted a revised petition, which NMFS deemed adequate and complete.
On May 9, 2018, we published a notice of receipt of Hilcorp's petition
in the Federal Register, requesting comments and information related to
the request for thirty days (83 FR 21276). We received comments from
the Center for Biological Diversity and 15,843 citizens opposing
issuance of the requested regulations and LOA. We also received
comments from the Alaska Eskimo Whaling Commission (AEWC) who
recommended we include subsistence-related mitigation and coordination
requirements in the final rule. On May 29, 2019, NMFS issued a notice
of proposed rulemaking in the Federal Register (84 FR 24926),
soliciting public comments for 30 days. The 30-day comment period was
subsequently extended to July 31, 2019, in response to a request from
the AEWC (84 FR 32697; July 9, 2019). All public comments were
considered in developing this final rule. To extract oil and gas in the
Liberty Oil Field, Hilcorp is proposing to construct a 9.3-acre
artificial island (the LDPI) in 19 feet (ft) (5.8 meters (m)) of water
in Foggy Island Bay, approximately 5 miles (mi) (8 kilometers (km))
north of the Kadleroshilik River and install supporting infrastructure
(e.g., ice roads, pipeline). Ice roads would be constructed annually
and begin December 2021. Island construction, which requires impact and
vibratory pile driving, is proposed to take one year to complete,
beginning in 2022. Pile driving would primarily occur during ice-
covered season (only ice seals are present during this time period);
however, up to two weeks of pile driving may occur during the open-
water season. Pipeline installation is anticipated to occur in 2023.
Drilling and production is proposed to occur from 2023 through 2026.
Hilcorp requests, and NMFS is authorizing, the take, by Level A
harassment and Level B harassment, of bowhead whales (Balaena
mysticetus), gray whales (Eschrichtius robustus), beluga whales
(Delphinapterus leucas), ringed seals (Phoca hispida), bearded seals
(Erignathus barbatus), and spotted seals (Phoca largha) incidental to
LDPI construction and operation activities (e.g., pile driving, ice
road and island construction). Hilcorp also requested, and NMFS is
authorizing, mortality and serious injury of two ringed seals
incidental to annual ice road construction over a 5-year period. The
regulations are effective from December 1, 2021, through November 30,
2026.
Changes From Proposed to Final Rule
There are minor changes from the proposed rule to the final rule.
While more detail can be found later in this document, we summarize the
changes here.
We modified the amount of authorized takes, by Level B harassment,
of bowhead whales in years two through five from one animal to five
animals per year. This change was to account for a potentially large
group of whales in lieu of a single animal entering the Level B
harassment isopleth. While these whales are extremely rare to Foggy
Island Bay, we believe this is a more conservative approach and allows
the applicant sufficient take coverage.
We also corrected the take table for gray whales to authorize the
take, by Level B harassment, of two gray whales per year. The proposed
rule preamble text indicated that two gray whales could be taken by
Level B harassment per year; however, the table incorrectly indicated
that only one gray whale take was authorized per year. Two animals per
year more adequately reflects average group size.
We also modified the mitigation measures during the Cross Island
bowhead whale hunt to comport with the Bureau of Ocean Energy
Management's (BOEM) Record of Decision for permitting the project. This
resulted in additional mitigation to ensure the taking of marine
mammals authorized in these regulations will effect the least
practicable adverse impact on subsistence uses as well as the least
practicable adverse impact on the species and their habitat.
Specifically, the proposed rule required Hilcorp to cease impact pile
driving during the Cross Island hunt. The new mitigation measure
mirrors BOEM's measure, which requires that all pile driving (impact
and vibratory) must cease by August 1 and not resume until the official
end of the hunt or when the quota is met. In addition, Hilcorp may not
operate LDPI-related vessels outside the McClure Island Group during
this time.
We also modified other mitigation and monitoring measures (e.g.,
requiring ice road observers be equipped with binoculars and protected
species observers (PSOs) be equipped with laser range finders) in
consideration of input provided in public comments.
Public comments on the proposed rule indicated some confusion over
the mitigation and monitoring distances for both ringed seal structures
and ringed seals themselves in the Ice Road and Ice Trail Best
Management Practices (BMPs). In light of public comments, Hilcorp
modified the BMPs to provide clarity and consistency with mitigation
and monitoring distances. Those changes, made to both the BMPs and
these final regulations, reflect a standard 150-m set back distance to
ringed seal structures (both lairs and breathing holes) and a 50-m
setback distance to ringed seals on ice.
Finally, the effective date of this final rule is advanced one year
from that in the proposed rule, as described in the Federal Register
document announcing our re-opening of the public comment period on the
proposed rule (84 FR 32697, July 9, 2019), to accommodate Hilcorp's
most recent construction schedule. The regulations are effective from
December 1, 2021, through November 30, 2026.
Description of the Specified Activity
Overview
Hilcorp is proposing to construct and operate the LDPI, a self-
contained offshore drilling and production facility located on an
artificial gravel island. Infrastructure and facilities necessary to
drill wells and process and export approximately 60,000 to 70,000
barrels of oil per day to shore would be installed on the island. To
transport oil, a pipeline from the island would be installed, tying
into the existing Bandami pipeline located on shore between the
Sagavanirktok and Kadleroshilik Rivers on Alaska's North Slope. To
access the island and move vehicles and equipment, ice roads would be
constructed annually. All island construction and pipeline installation
would occur as much as possible during the winter months; however, pile
driving and slope protection could occur during the open water season.
Drilling and production, once begun, would occur year round. After
island and pipeline construction, Hilcorp would commence and continue
drilling and production for approximately 20 to 25 years at which time
the island would be decommissioned. The regulations and LOA cover the
incidental take of marine mammals during LDPI construction and
operation for the first five years of work. Thereafter, data collected
during these five years (e.g., acoustic monitoring during drilling, ice
road marine
[[Page 70276]]
mammal monitoring) would determine if future incidental take
authorizations are warranted for continuing operations.
Dates and Duration
The regulations are valid for a period of five years from December
1, 2021, through November 30, 2026. Ice road construction and pipeline
installation would be limited to winter months. Island construction
would be conducted primarily during winter months; however, given that
construction schedules are subject to delays for multiple reasons,
Hilcorp anticipates, at most, up to two weeks of open-water sheet pile
driving may be required in the first year to complete any pile driving
not finished during the winter. Other work, such as island slope
armoring, may also occur during open-water conditions. All island
construction would commence and is expected to be completed in the
first year of the regulations (December 2021 through November 2022).
Pipeline installation would occur in year 2 of the regulations
(December 2022 through November 2023), while drilling and production
would begin in year 3 and continue through the life of the regulations.
Ice road construction and maintenance activities would occur each
winter.
Specified Geographical Region
The Liberty field is located in Federal waters of Foggy Island Bay,
Beaufort Sea, about 8.9 km (5.5 mi) offshore in 6.1 m (20 ft) of water,
approximately 8 to 13 km (5 to 8 mi) east of the existing Endicott
Satellite Drilling Island (SDI) and approximately 32 km (20 mi) east of
Prudhoe Bay. Hilcorp would construct the Liberty project on three
leases, OCS-Y-1650, OCS-Y-1886, and OCS-Y-1585. The proposed LDPI would
be constructed in 19 ft (5.8 m) of water about 5 mi (8 km) offshore in
Foggy Island Bay. The LDPI and all associated infrastructure (e.g., ice
roads) are located inside the McClure barrier island group which
separates Foggy Island Bay from the Beaufort Sea (Figure 1).
BILLING CODE 3510-22-P
[GRAPHIC] [TIFF OMITTED] TR20DE19.000
[[Page 70277]]
BILLING CODE 3510-22-C
Detailed Description of Activities
The Liberty Prospect is located 8.85 km offshore in about 6 m of
water, inside the Beaufort Sea's barrier islands. Hilcorp, as the
Liberty operator, is proposing to develop the Liberty Oil Field
reservoir, located on the Outer Continental Shelf (OCS), in Foggy
Island Bay, Beaufort Sea, Alaska. The Liberty reservoir is the largest
delineated but undeveloped light oil reservoir on the North Slope. It
is projected to deliver a peak production rate of between 60,000 and
70,000 barrels of oil per day within two years of initial production.
Total recovery over an estimated field life of 15 to 20 years is
predicted to be in the range of 80 to 150 million stock tank barrels of
oil. The Liberty Oil Field leases were previously owned by BP
Exploration Alaska, Inc. (BPXA). In April 2014, BPXA announced the sale
of several North Slope assets to Hilcorp, including the area where the
proposed LDPI would be constructed and other existing oil production
islands (Northstar, Endicott, Milne Point). The Liberty Project has
many similarities to previous oil and gas islands constructed on the
North Slope, including Endicott, Northstar, and Oooguruk.
The proposed LDPI project includes development of a mine-site to
supply gravel for the construction of the LDPI, construction of the
island and annual ice roads, installation of an undersea pipeline that
reaches shore from the LDPI and then connects to the existing above-
ground Badami pipeline, drilling, production, and operation (for
simplicity, hence forward we refer to both production and operation as
``production''). The mine site is located inland of marine mammal
habitat over which NMFS has jurisdiction; therefore, its development
will not be discussed further in this rule as no impacts to marine
mammals under NMFS jurisdiction would be affected by this project
component. Here, we discuss those activities that have the potential to
take marine mammals: Ice road construction and maintenance, island
construction (pile driving and slope armoring), pipeline installation,
drilling, and production. We also describe auxiliary activities,
including vessel and aircraft transportation. A schedule of all phases
of the project and a summary of equipment and activities involved are
included in Table 1a with more details on schedule provided in Table
1b.
Table 1a--LDPI Project Components, Schedule, and Associated Equipment
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Regulation
Project component year Season Equipment and activity
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Ice road construction, use, and 1-5 Ice-covered.............. Grader, ice auger, trucks
maintenance. (flood road, haul gravel,
general transit,
maintenance).
Island construction................... * 1 Ice-covered, open water.. Impact and vibratory pile and
pipe driving, backhoe
(digging), excavator (slope
shaping, armor installation,
ditchwitch (sawing ice).
Pipeline installation................. 2 Ice-covered.............. Ditchwitch (sawing ice),
backhoe (digging), trucks.
Drilling and production............... 3-5 Ice-covered, open water.. Drill rig, land-based
equipment on island (e.g.,
generators).
Marine vessel and aircraft support.... 1-5 Open-water, ice-covered Barge, tugs, crew boats,
(helicopter only). helicopter.
Emergency and oil response training... 1-5 Ice-covered, open water.. Vessels, hovercrafts, all-
terrain vehicles, snow
machines, etc.
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* Hilcorp has indicated a goal to complete all LDPI construction in the first year the regulations would be
valid; however, they may need to install foundation piles in year 2.
Table 1b--Dominant Noise Source by Month and Days of Each Activity
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Season Month Year 1 Year 2 Year 3 Year 4 Year 5
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Ice-covered Season.............. Dec, Jan.......... Ice Road Ice Road Drilling and Drilling and Drilling and
Construction (62 Construction (62 Production (212 Production (212 Production (212
days). days). days). days). days)
Feb, March, April. Island Facility
Construction (89 Construction (150
days). days)
May............... Island
Construction (14
days).
Vibratory Sheet
Pile Driving.
(17 days).........
June.............. Vibratory Sheet
Pile Driving (30
days)
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Open-water Season............... July.............. Vibratory Sheet Foundation Piles Drilling and Drilling and Production (123
Pile Driving (15 Installation (31 Production (123 Production (123 days).
days).. days). days). days).
Slope Shaping (16
days).
Aug............... Slope Shaping (31 Rig Mobilization &
days). Well Prep (92
days)
Sept, Oct......... Rig Mobilization &
Well Prep (61
days)
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Ice-covered Season.............. Nov............... Rig Mobilization & Drilling and Drilling and Drilling and Production (30
Well Prep (30 Production (30 Production (30 Production (30 days)
days). days). days). days).
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Ice Road and Ice Pad Construction and Maintenance
Hilcorp will construct ice roads and perform maintenance, as
necessary. Ice roads are a route across sea ice created by clearing and
grading snow then pumping seawater from holes drilled through the
floating ice. Some roads may use grounded ice. Hilcorp would clear away
snow using a tractor, bulldozer, or similar piece of equipment, then
pump seawater from
[[Page 70278]]
holes drilled through floating ice, and then flood the ice road. The
ice roads will generally be constructed by pumper units equipped with
an ice auger to drill holes in the sea ice and then pump water from
under the ice to flood the surface of the ice. The ice augers and
pumping units will continue to move along the ice road alignment to
flood the entire alignment, returning to a previous area as soon as the
flooded water has frozen. The ice road will be maintained and kept
clean of gravel and other solids. Freshwater can be sprayed onto the
road surface to form a cap over the main road structure for the top
layer or to repair any cracks.
Ice roads will be used for onshore and offshore access, installing
the pipeline, hauling gravel used to construct the island, moving
equipment on/off island, personnel and supply transit, etc. Ice roads
are best constructed when weather is -20 degrees Fahrenheit (F) to -30
degrees F, but temperatures below 0 degree F are considered adequate
for ice road construction. Ice road construction can typically be
initiated in mid- to late-December and can be maintained until mid-May.
At the end of the season, ice roads will be barricaded by snow berm
and/or slotted at the entrance to prevent access and allowed to melt
naturally. Figure 1 shows the locations of the proposed ice roads.
Ice road #1 will extend approximately 11.3 km (7 mi) over
shorefast sea ice from the Endicott SDI to the LDPI (the SDI to LDPI
ice road). It will be approximately 37 m wide (120 ft) with a driving
lane of approximately 12 m (40 ft). It would cover approximately 160
acres of sea ice.
Ice road #2 (approximately 11.3 km (7 mi)) will connect
the LDPI to the proposed Kadleroshilik River gravel mine site and then
will continue to the juncture with the Badami ice road (which is ice
road #4). It will be approximately 15 m (50 ft) wide.
Ice road #3 (approximately 9.6 km [6 mi], termed the
``Midpoint Access Road'') will intersect the SDI to LDPI ice road and
the ice road between the LDPI and the mine site. It will be
approximately 12 m (40 ft) wide.
Ice road #4 (approximately 19.3 km (12 mi)), located
completely onshore, will parallel the Badami pipeline and connect the
mine site with the Endicott road.
All four ice roads would be constructed for the first three years
to support pipeline installation and transportation from existing North
Slope roads to the proposed gravel mine site, and from the mine site to
the proposed LDPI location in the Beaufort Sea. After year 3, only ice
road #1 would be constructed to allow additional materials and
equipment to be mobilized to support LDPI, pipeline, and facility
construction activities as all island construction and pipeline
installation should be complete by year 3. Winter sea ice road/trail
construction will begin as early as possible (typically December 1
through mid-February). It is anticipated that all ice road construction
activities will be initiated prior to March 1, before the time when
female ringed seals establish birth lairs.
In addition to the ice roads, three ice pads are proposed to
support construction activities (year 2 and 3). These would be used to
support LDPI, pipeline (including pipe stringing and two stockpile/
disposal areas), and facilities construction. A fourth staging area ice
pad (approximately 350 feet by 700 feet) would be built on the sea ice
on the west side of the LDPI during production well drilling
operations.
Other on-ice activities occurring prior to March 1 could also
include spill training exercises, pipeline surveys, snow clearing, and
work conducted by other snow vehicles such as a Pisten Bully, snow
machine, or rollagon. Prior to March 1, these activities could occur
outside of the delineated ice road/trail and shoulder areas.
LDPI Construction
The LDPI will include a self-contained offshore drilling and
production facility located on an artificial gravel island with a
subsea pipeline to shore. The LDPI will be located approximately 8
kilometers (km) or 5 miles (mi) offshore in Foggy Island Bay and 11.7
km (7.3 mi) southeast of the existing SDI on the Endicott causeway (see
Figure 1). The LDPI will be constructed of reinforced gravel in 5.8
meters (m) (19 feet (ft)) of water and have a working surface of
approximately 3.8 hectares (ha) (9.3 acres (ac)). A steel sheet pile
wall would surround the island to stabilize the placed gravel and the
island would include slope protection bench, dock and ice road access,
and a seawater intake area (Figure 2).
[[Page 70279]]
[GRAPHIC] [TIFF OMITTED] TR20DE19.001
Hilcorp would begin constructing the LDPI during the winter
immediately following construction of the ice road from the mine site
to the island location. Sections of sea ice at the island's location
would be cut using a ditchwitch and removed. A backhoe and support
trucks using the ice road would move ice away. Once the ice is removed,
gravel will be poured through the water column to the sea floor,
building the island structure from the bottom up. A conical pile of
gravel (hauled in from trucks from the mine site using the ice road)
will form on the sea floor until it reaches the surface of the ice.
Gravel hauling over the ice road to the LDPI construction site is
estimated to continue for 50 to 70 days, and conclude mid-April or
earlier depending on road conditions. The construction would continue
with a sequence of removing additional ice and pouring gravel until the
surface size is achieved. Following gravel placement, slope armoring
and protection installation would occur. Using island-based equipment
(e.g., backhoe, bucket-dredge) and divers, Hilcorp would create a slope
protection profile consisting of a 60-ft (18.3 m) wide bench covered
with a linked concrete mat that extends from a sheet pile wall
surrounding the island to slightly above mean low low water (MLLW)
(Figure 3). The linked concrete mat requires a high strength, yet
highly permeable, woven polyester fabric under layer to contain the
gravel island fill. The filter fabric panels will be overlapped and
tied together side-by-side (requiring diving operations) to prevent the
panels from separating and exposing the underlying gravel fill. Because
the fabric is overlapped and tied together, no slope protection debris
would enter the water column should it be damaged. Above the fabric
under layer, a robust geo-grid will be placed as an abrasion guard to
prevent damage to the fabric by the linked mat armor. The concrete mat
system would continue at a 3:1 slope another 86.5 ft into the water,
terminating at a depth of -19 ft (-5.8 m). In total, from the sheet
pile wall, the bench and concrete mat would extend 146.5 ft. Island
slope protection is required to assure the integrity of the gravel
island by protecting it from the erosive forces of waves, ice ride-up,
and currents. A detailed inspection of the island slope protection
system will be conducted annually during the open-water season to
document changes in the condition of this system that have occurred
since the previous year's inspection. Any damaged material would be
removed. Above-water activities will consist of a visual inspection of
the dock and sheet pile enclosure that will document the condition of
the island bench and ramps. The below-water slopes will be inspected by
divers or, if water clarity allows, remotely by underwater cameras
contracted separately by Hilcorp. The results of the below-water
inspection will be recorded for repair if needed. No vessels will be
required. Multi-beam bathymetry and side-scan sonar imagery of the
below-water slopes and adjacent sea bottom will be acquired using a
bathymetry vessel. The sidescan sonar would operate at a frequency
between 200-400 kilohertz (kHz). The single-beam echosounder would
operate at a frequency of about 210 kHz.
[[Page 70280]]
[GRAPHIC] [TIFF OMITTED] TR20DE19.002
Once the slope protection is in place, Hilcorp would install the
sheet pile wall around the perimeter of the island using vibratory and,
if necessary, impact hammers. Hilcorp anticipates driving up to 20
piles per day to a depth of 25 ft. A vibratory hammer would be used
first, followed by an impact hammer to ``proof'' the pile. Hilcorp
anticipates each pile needing 100 hammer strikes over approximately 2
minutes of impact driving to obtain the final desired depth for each
sheet pile. This equates to a maximum of 40 minutes and 2,000 strikes
of impact hammering per day. For vibratory driving, pile penetration
speed can vary depending on ground conditions, but a minimum sheet pile
penetration speed is 20 inches (0.5 m) per minute to avoid damage to
the pile or hammer (NASSPA 2005). For this project, the anticipated
duration is based on a preferred penetration speed greater than 40
inches (1 m) per minute, resulting in 7.5 minutes to drive each pile.
Given the high storm surge and larger waves that are expected to arrive
at the LDPI site from the west and northwest, the wall will be higher
on the west side than on the east side. At the top of the sheet-pile
wall, overhanging steel ``parapet'' will be installed to prevent wave
passage over the wall.
Within the interior of the island, 16 steel conductor pipes would
be driven to a depth of 160 ft (49 m) to provide the initial stable
structural foundation for each oil well. They would be set in a well
row in the middle of the island. Depending on the substrate, the
conductor pipes would be driven by impact or vibratory methods or both.
During the construction of the nearby Northstar Island (located in
deeper water), it took 5 to 8.5 hours to drive one conductor pipe
(Blackwell et al., 2004). For the Liberty LDPI, Hilcorp anticipates it
would take two hours of active pile driving per day to install a
conductor pipe given the 5 to 8.5 hour timeframe at Northstar includes
pauses in pile driving and occurred in deeper water requiring deeper
pile depths. In addition, approximately 700 to 1,000 foundation piles
may also be installed within the interior of the island should
engineering determine they are necessary for island support.
Pipeline Installation
Hilcorp would install a pipe-in-pipe subsea pipeline consisting of
a 12-in diameter inner pipe and a 16-in diameter outer pipe to
transport oil from the LDPI to the existing Bandami pipeline. Pipeline
construction is planned for the winter after the island is constructed.
A schematic of the pipeline can be found in Figure 2-3 of BOEM's Final
Environmental Impact Statement (FEIS) available at https://www.boem.gov/Hilcorp-Liberty/. The pipeline will extend from the LDPI,
across Foggy Island Bay, and terminate onshore at the existing Badami
Pipeline tie-in location. For the marine segment, construction will
progress from shallower water to deeper water with multiple
construction spreads.
To install the pipeline, a trench will be excavated using ice-road
based long-reach excavators with pontoon tracks. The pipeline bundle
will be lowered into the trench using side booms to control its
vertical and horizontal position, and the trench will be backfilled by
excavators using excavated trench spoils and select backfill. Hilcorp
intends to place all material back in the trench slot. All work will be
done from ice roads using conventional excavation and dirt-moving
construction equipment. The target trench depth is 9 to 11 ft (2.7 to
3.4 m) with a proposed maximum depth of cover of approximately 7 ft
(2.1 m). The pipeline will be approximately 5.6 mi (9 km)
[[Page 70281]]
long. Hydro-testing (pressure testing using sea water) of the entire
pipeline will be completed prior to commissioning.
Drilling and Production
The final drill rig has yet to be chosen by Hilcorp but has been
narrowed to two options and will accommodate drilling of 16 wells. The
first option is the use of an existing platform-style drilling unit
that Hilcorp owns and operates in the Cook Inlet. Designated as Rig
428, the rig has been used recently and is well suited in terms of
depth and horsepower rating to drill the wells at Liberty. A second
option that is being investigated is a new build drilling unit that
would be built to not only drill Liberty development wells, but would
be more portable and more adaptable to other applications on the North
Slope. Regardless of drill rig type, the well row arrangement on the
island is designed to accommodate up to 16 wells. We note that while
Hilcorp is proposing a 16-well design, only 10 wells would be drilled.
The 6 additional well slots would be available as backups or for
potential in-fill drilling if needed during the project life.
Process facilities on the island will separate crude oil from
produced water and gas. Gas and water will be injected into the
reservoir to provide pressure support and increase recovery from the
field. A single-phase subsea pipe-in-pipe pipeline will transport
sales-quality crude from the LDPI to shore, where an aboveground
pipeline will transport crude to the existing Badami pipeline. From
there, crude will be transported to the Endicott Sales Oil Pipeline,
which ties into Pump Station 1 of the TransAlaska Pipeline System
(TAPS) for eventual delivery to a refinery.
Comments and Responses
Notice of NMFS's proposal to issue regulations to Hilcorp was
published in the Federal Register on May 29, 2019 (84 FR 24926). That
document described, in detail, Hilcorp's proposed activity, the marine
mammal species that may be affected by the activity, and the
anticipated effects on marine mammals. At the request of the Alaska
Eskimo Whaling Commission (AEWC), NMFS reopened the public comment
period until July 31, 2019 (84 FR 32697; July 9, 2019). During the
public comment period, NMFS received comments from the Marine Mammal
Commission (the Commission); Alaska Wilderness League (AWL), on behalf
of the Animal Welfare Institute, Center for Biological Diversity,
Defenders of Wildlife, Earthjustice, Environmental Investigation
Agency, Eyak Preservation Council, Friends of the Earth, and Northern
Alaska Environmental Center; AEWC; North Slope Borough (NSB); and seven
private citizens. These comments and our responses are described below.
Comment 1: The Commission recommends that NMFS consult with
external scientists and acousticians to determine the appropriate
accumulation time that action proponents should use to determine the
extent of the Level A harassment zones based on the associated
cumulative sound exposure level (SELcum) thresholds for the various
types of sound sources, including stationary sound sources.
Response: The Commission has raised this concern before and NMFS
has previously responded that NMFS considers this a priority and has
formed a Working Group to focus on the issue of accumulation time. Once
the NMFS internal Working Group develops a proposal, it will be shared
with Federal partners and other stakeholders. However, in the meantime,
as we have described previously, Hilcorp used a sophisticated modeling
approach that considered the full duration of activity within a day
which allows for a conservative estimate of the distances at which
marine mammals could potentially experience injurious sound levels if
they were subject to the full duration of exposure.
Comment 2: The Commission recommends that NMFS include in the
preamble of the final rule all of the inputs it used to estimate takes
by Level A and B harassment, including the type of activity that will
occur during each season and the number of days each season that each
activity will occur.
Response: All of the inputs into the Level A harassment analysis,
including ensonified areas, are included in the final rule. NMFS also
provided a table in the final rule that lists the activities with the
greatest potential for take and the number of days each season that the
activities are anticipated to occur in each year of the 5-year
regulations (Table 1b).
Comment 3: The Commission believes that the number of Level A
harassment takes for ringed seals have been underestimated and claims
there is the potential for at least one ringed seal to be taken by
Level A harassment each day that impact pile driving occurs,
particularly since it appears that impact pile driving could occur
intermittently throughout a given day. The Commission recommends that
NMFS increase the number of Level A harassment takes of ringed seals
from 5 to at least 15 during Year 1 considering 15 days of open-water
pile driving could occur.
Response: The estimated number of marine mammals that may be
potentially exposed to noises exceeding NMFS' established thresholds
was calculated based on marine mammal density estimates, the ensonified
area, and the duration of each project activity. The Commission's
recommendation does not provide reason for why this standard approach
is not acceptable. In addition, the Commission has inaccurately
characterized the Level A harassment distance output of the model as
the distance at which an animal will immediately incur permanent
threshold shift (PTS) if it crosses that distance. However, this is not
the case as described in the Technical Guidance (NMFS 2018). The Level
A threshold distance represents the distance at which an animal could
incur PTS if it remains at that distance for the duration considered in
the model. An animal crossing this distance for a shorter period of
time does not necessarily incur PTS. The Level A isopleth calculations
included a conservative 40 minutes of active impact pile driving per
day, which does not consider the time it takes to reset for piles, and
Footnote 2 in Table 4 indicates the average duration of impact driving
per day is closer to 20 minutes, which would result in a much smaller
Level A harassment distance and, again, the animal would have to remain
at that distance for that period of time. The Commission also states
that Hilcorp would not be required to shut down if a seal comes within
the Level A harassment isopleth; however, as described in Hilcorp's
application, the proposed rule, and this final rule, if a seal enters
the Level A harassment zone while pile driving is ongoing, work may
continue until the pile is completed (estimated to require
approximately 15-20 minutes), but additional pile driving must not be
initiated until the animal has left the Level A harassment zone. The
Commission also does not consider seasonal density of ringed seals,
which is very low during the summer when impact pile driving during
open-water could occur, further reducing the potential for Level A
harassment take. For these reasons, NMFS does not agree with the
Commission's recommendation and, as in the proposed rule, the final
rule authorizes the take, by Level A harassment, of five ringed seals
in year 1 incidental to pile driving as this is the calculated Level A
harassment take based on seal density, the ensonified area, and the
number of impact pile driving days.
[[Page 70282]]
Comment 4: The Commission recommends that NMFS revise the numbers
of Level B harassment takes for all species to account for vibratory
driving occurring at any of the five sides of the island during the
open-water season and, unless Hilcorp has contrary data regarding how
many days vibratory driving would occur at each of the five sides of
the island, assume that pile driving would occur for three days at each
of the five sides. This recommendation is based on the proposed rule's
approach that Level B harassment takes during sheet pile driving during
the open-water season were based on an ensonified area of 64 km\2\ for
each of the estimated 15 days of pile driving. That ensonified area is
associated with the southwest side of the island, which was the
smallest of the ensonified areas associated with each of the five sides
of the island.
Response: Hilcorp stated several times in their application,
correspondence with NMFS, and during the peer-review panel that they
intend to conduct all sheet pile driving during the ice-covered season,
as was done with Northstar. This information is provided in their
description of the specified activity. However, as a precautionary
measure, two weeks to complete sheet piling driving during open water
(early July) have been included for estimating potential marine mammal
takes. Hilcorp's construction process validates the reason for using
the southwest perimeter acoustic model results (64 km\2\) in the take
estimate. Hilcorp proposes to begin vibratory sheet pile driving on the
north end of LDPI during ice-covered conditions, progressing around the
island perimeter and finishing with sheet pile driving on the southwest
side of the island. Therefore, although ideally all pile driving would
be done during the ice-covered season, the only part of the island
which could be unfinished by the open-water period is the southwest
side of the island. The Commission's recommendation to assume three
days of pile driving at each of the five sides is inconsistent with
Hilcorp's construction plan. For these reasons, NMFS used the SW
ensonified area of 64 km\2\ to estimate marine mammal takes while also
accounting for group size in its take authorization, as presented in
the proposed rule. In addition, we note that NMFS adjusted cetacean
take numbers from a simple density estimate, which uses an ensonified
area, to one that accounts for group size and previous monitoring data,
raising all take numbers born from estimates that solely relied on
ensonified area. For example, the estimated density of gray whales in
Foggy Island Bay is zero, therefore even if different ensonified areas
were used, the outcome of takes based solely on the ensonified area
would always be zero; however, by also including group size and
previous monitoring data, the Level B harassment take estimate for gray
whales is two per year.
Comment 5: The Commission recommends that NMFS increase the Level B
harassment takes of gray whales from one to two annually in Years 1
through 5 and that NMFS increase the Level B harassment takes of
bowhead whales to account for the typical group size of two to five
whales annually in Years 2 through 5.
Response: Although gray whales and bowhead whales are extremely
rare in Foggy Island Bay, NMFS agrees to conservatively account for
group sizes of these species in the open Beaufort Sea. This final rule
authorizes the take, by Level B harassment, of two gray whales,
annually for the life of the regulations, and five bowhead whales,
annually in years 2-5 of the final rule, incidental to the proposed
project. As in the proposed rule, NMFS estimates that six bowhead
whales may be taken by Level B harassment in year 1 of the regulations.
Comment 6: If there is a possibility that pile driving could occur
after the Nuiqsut Cross Island hunt, the Commission recommends that
NMFS re-estimate the number of Level B harassment takes, as well as
Level A harassment takes for bowhead whales since they occur in greater
numbers, and thus higher densities, in the fall (September through
October).
Response: Other than to account for large group size (see above),
NMFS did not adjust bowhead whale take numbers. It is very unlikely
Hilcorp would conduct pile driving after the Cross Island hunt as this
is not in their project plan. Hilcorp intends to conduct all sheet pile
driving during the ice-covered months as was done with Northstar. Some
sheet pile driving during the open-water season was included in the
rulemaking analysis to conservatively account for any delays resulting
in the need for sheet pile driving during that time.
Comment 7: The Commission recommends that NMFS specify in the final
rule that the Level A harassment zones equate to the shut-down zones
and the relevant circumstances when they apply. The AWL made a similar
comment and we address both here.
Response: As described in the proposed rule (84 FR 24955) and this
final rule, in the unlikely event a low frequency cetacean (bowhead or
gray whale) approaches or enters the Level A harassment zone, pile
driving would be shut down. This measure is designed to provide the
most protection practicable for large whales included in subsistence
uses. If a mid-frequency cetacean (beluga) or pinniped (seal) enters
the Level A harassment zone during pile driving, Hilcorp could complete
setting the pile (which takes ten to fifteen minutes from commencement)
but not initiate additional pile driving of new piles until the marine
mammal has left and is on a path away from the Level A harassment zone.
This measure is also included in section 217.34 of the proposed and
final regulations. As such, the Commission's recommendation to specify
the Level A harassment zones equate to the shut-down zones is not
necessary. The Commission and AWL's confusion appears to be generated
by one statement in parentheses in the proposed rule preamble that did
not clearly identify that the shut-down zone is equal to Level A
harassment zone only for low frequency cetaceans. NMFS corrected this
statement in the final rule to clarify the Level A zone is equal to the
shut-down zone only for low frequency cetaceans.
Comment 8. The Commission recommends that NMFS make the Wildlife
Action Plan available to the public and provide an additional
opportunity for review and comment on both the BMPs and the Wildlife
Action Plan prior to issuing the final rule.
Response: NMFS posted both the BMPs and the relevant sections of
the Wildlife Action Plan during the initial public comment period.
These documents were also available during the second public comment
period.
Comment 9: The Commission recommends that NMFS include the
following requirements in the final rule: (1) That Hilcorp conduct PAM
[passive acoustic monitoring] using a hand-held hydrophone deployed
through the ice during the ice-covered season and (2) Hilcorp include
in its annual reports and final report an extrapolated total take
estimate for each species based on the number of marine mammals
observed and the extent of the harassment zones during the applicable
construction activities.
Response: The proposed and final rule includes the requirement that
Hilcorp conduct PAM using a hand-held hydrophone. This requirement is
also in both the Marine Mammal Mitigation and Monitoring Plan (4MP) and
the Acoustic Monitoring Plan which the Commission reviewed concurrently
with the proposed rule. In the final rule, NMFS has added a requirement
that Hilcorp provide in its annual and final
[[Page 70283]]
report an extrapolated total take estimate for each species.
Comment 10: The Commission recommends that NMFS ensure the minimum
distance specified in the final rule, 4MP, and BMPs for avoidance of
ringed seals and lairs is at least 150 m, not 150 ft (we note AWL
provided a similar comment) and that NMFS clarify in the preamble to
the final rule its rationale for not incorporating the peer-review
panel's recommendations to (1) increase the avoidance distance for
ringed seals and lairs to 300 m and (2) investigate the availability of
laser range finders that would improve the resolution and range of
detections of marine mammals beyond 600 m.
Response: The final rule makes corrections and clarifies the
minimum distances of approach for ringed seals and ringed seal
structures. The minimum distance to avoid ringed seals remains as
stated in the proposed rule and BMPs as 50 m. The minimum distance to
avoid ringed seal structures (e.g., lairs, breathing holes) in this
final rule is 150 m. The BMP entries, which appear to be the source of
confusion for the Commission and AWL, have been modified and are
available at https://www.fisheries.noaa.gov/permit/incidental-take-
authorizations-under-marine-mammal-protection-act. With respect to the
peer-review panel's recommendation, they provided no justification for
why the proposed avoidance distances were not appropriate nor did they
provide justification for the 300-m recommendation. A 300-m avoidance
distance of both seals and lairs is three times greater than the NMFS
marine mammal viewing guidelines recommendation and is not practicable
for the applicant to carry out ice-road work. For these reasons, NMFS
did not accept the peer-review panel's 300-m avoidance recommendation.
We note that the peer-review panel's report made one mention of
range finders and recommended user range finders that would improve
resolution and range detections of marine mammals beyond 600 m. The 4MP
indicates distances to nearby marine mammals will be estimated with
binoculars containing a reticle to measure the vertical angle of the
line of sight to the animal relative to the horizon. However, for a
more immediate distance estimator tool, NMFS has included the
requirement for PSOs to be equipped with rangefinders.
Comment 10: AWL asserts the proposed rule employs an unlawful small
numbers analysis that arbitrarily fails to consider the full suite of
impacts from the operation of the Liberty project on marine mammals in
that NMFS ignores takes that will occur from operation of the Liberty
project.
Response: Hilcorp requested authorization for the take of six
species of marine mammals incidental to construction and operation of
the proposed LDPI during the five-year period from December 1, 2021,
through November 30, 2026. NMFS does not ignore takes that will occur
from operation of the Liberty project during that period. The acoustic
models indicate there is potential for NMFS Level B harassment
thresholds to be reached during drilling (i.e., operation)
approximately 230 m and 55 m from the island during ice and open-water
conditions, respectively. Animal density, by species, was considered
with respect to these ensonified areas and accounted for in the take
estimates. Therefore, NMFS has analyzed and authorized takes for
operation (i.e., drilling) of the Liberty project. During the onset of
drilling and production, Liberty will perform acoustic measurements to
determine if the model accurately predicted these harassment isopleths,
and future requests for take authorizations after the regulations have
expired will be contingent upon those measurements.
Comment 11: AWL expressed concern that NMFS used the median range
of radial distances to NMFS Level B harassment thresholds to determine
the ensonified area in which takes would occur. They assert that use of
the median range could lead to roughly 50 percent of an exposed cohort
experiencing impacts that are not accounted for in NMFS's analysis.
They assert NMFS' approach contravenes the precautionary nature of the
MMPA and the statutory definition of harassment, which includes not
only those actions that will injure or disturb marine mammals, but
those that have the potential to do so.
Response: It is NMFS standard practice to apply median source
levels when determining distances to NMFS harassment thresholds. By
using the median, we eliminate the few loud outliers in the data,
better representing the overall acoustic footprint of the project. NMFS
notes that using the median harassment isopleth also does not translate
into underestimating an exposed cohort by 50 percent as the AWL
asserts. This is because the median harassment isopleth distance is not
half of the maximum isopleth (which is derived by applying the absolute
maximum source level). For example, the median Level B harassment
isopleth for impact driving sheet piles is 2,050 m while the maximum is
2,250 m. Similarly, the median Level B harassment isopleth for impact
driving pipe piles is 315 m while the maximum is 400 m. Because take is
based on the density of animals in a given area, the area (which is
derived from isopleth distances) would have to be 50 percent less to
have a 50 percent reduction in take. More importantly, all predicted
cetacean takes were adjusted upwards to account for group size so the
actual take authorized is greater than any predicted take based on
density and harassment isopleth distances. For these reasons, we
believe we have accurately accounted for the potential for takes of all
species.
Regarding Level B harassment, based on the language and structure
of the definition of Level B harassment, we interpret the concept of
``potential to disturb'' as embedded in the assessment of the
behavioral response that results from an act of pursuit, torment, or
annoyance (collectively referred to hereafter as an ``annoyance''). The
definition refers to a ``potential to disturb'' by causing disruption
of behavioral patterns. Thus, an analysis that indicates a disruption
in behavioral patterns establishes the ``potential to disturb.'' A
separate analysis of ``potential to disturb'' is not needed.
Comment 12: AWL believes NMFS ignores takes that will occur from
ship strikes and noise pollution from vessel and air traffic associated
with the Liberty project. These activities may cause takes of all the
species analyzed in the agency's proposed rule--bowhead whales, gray
whales, beluga whales, spotted seals, ringed seals, and bearded seals--
as well as a host of other species (North Pacific right whales,
humpback whales, minke whales, fin whales, killer whales, sperm whales,
harbor porpoise, Dall's porpoise, beaked whales, Steller sea lions,
harbor seals, and ribbon seals) not included in the analysis.
Response: NMFS does not ignore impacts from ship strikes and noise
from vessel and air traffic associated with the Liberty project. As
described in the analysis, the probability of a ship strike from the
specified activities is very low and, further, Hilcorp proposed, and
NMFS included, a number of measures to further reduce the likelihood of
vessel interactions. Accordingly, takes from ship strikes are neither
anticipated nor authorized. Regarding ship traffic noise, the impacts
of vessel traffic from these activities are assessed and considered in
NMFS' Biological Opinion, Hilcorp's application, and the proposed rule
(e.g., 84 FR 24945, May 29, 2019), and while marine mammals may respond
to vessel traffic, responses rising to the level of a
[[Page 70284]]
take are considered unlikely to occur and are not authorized here. As
for aircraft, the critical angle necessary for noise to enter the water
column from airborne sources is very small. While aircraft flying low
directly overhead may be audible to a cetacean (whose ears are adapted
to underwater hearing), it is highly unlikely that noise would cause
changes to patterns of behavior that would rise to a level of a take.
For all species, including pinnipeds, behavioral harassment would be
minimized through mitigation measures that establish minimum flight
altitudes, as described in the Biological Opinion and which has been
added as a mitigation measure to this final rule. Hence, NMFS disagrees
these activities have the potential to take the species AWL believes
NMFS did not include in the analysis.
Comment 13: AWL believes NMFS improperly lumps together the take of
marine mammals that it acknowledges will occur. For example, NMFS
ignores the impacts of masking from pile driving that might rise to
Level B harassment because it will occur concurrently with harassment
already considered in estimating takes from vibratory and impact pile
driving.
Response: NMFS disagrees with AWL's characterization. A detailed
discussion on masking is presented on page 24944 of the proposed rule
(84 FR 24926; May 29, 2019) and noted throughout the Auditory Effects
section of that document. NMFS qualitatively considers masking in its
analysis. NMFS does not quantify and authorize separate Level B
harassment takes based on the stressor (e.g., masking vs. stress,
etc.), rather, we evaluate the number of takes anticipated to occur and
then assess the impacts of the authorized take on the individual (and
subsequently the population), qualitatively considering the nature of
the takes that are anticipated to occur, e.g., whether they are more or
less severe, or what kind of stressor or stressors they are resulting
from. Accordingly, while all stressors are appropriately considered in
the analysis (quantitatively or qualitatively), a total amount of Level
B harassment takes are authorized.
Comment 14: AWL asserts that repeated exposures should be
considered as separate takes, because they will repeatedly affect
auditory and behavioral responses. AWL is concerned NMFS appears to
count any exposure that occurs over the course of a given day as one
take.
Response: While NMFS' analysis fully considers the nature of any
takes that will occur (e.g., the severity, whether they are comprised
of multiple exposures within a day, the duration of the exposure), for
the purposes of consistency in tracking across projects and
practicality for applicant implementation, and in consideration of the
fact that many marine mammal behaviors and responses are linked to a
diel cycle, NMFS appropriately uses a daily metric to count takes for
the purposes of authorization. Specifically we do not consider one
individual animal as taken more than one time in a day and, the
corollary of that--we consider takes that occur in a subsequent 24-hour
period a separate instance of take, even if they may be accruing to the
same individual. These basic rules allow for consistent and reliable
estimation of take and, further, it is rarely the case that there is
adequate information to predict impacts with any precision at a more
granular level. Accordingly, we count multiple exposures in one day to
an individual as one take, but our analysis considers the severity and
nature of each take in our negligible impact analysis.
Comment 15: AWL asserts that NMFS's analysis also improperly
ignores the species-particular behaviors and life-stages of animals at
the anticipated times and places that takes would occur and that
responses of marine mammals to noise generated by the project may be
markedly different depending on what the animal is doing, time of year
(i.e., season), or life-stage of the animal at the time of exposure.
Response: NMFS analyzed both species-specific behaviors and life-
stages in the proposed rule. For example, cetaceans are not present in
Foggy Island Bay during the ice-covered periods; therefore, we
determined there was no potential for harassment to cetaceans during
this time period. NMFS also investigated and described the potential
effects of ice road construction during ringed seal lairing time
periods and specifically discussed that to offset impacts to
reproductive behaviors by ringed seals (e.g., lairing, pupping),
Hilcorp would follow a number of ice road BMPs developed in
coordination with NMFS ringed seal experts. During the open-water
season, NMFS identified in the proposed rule that cetaceans rarely use
Foggy Island Bay and has clarified in the final rule that Foggy Island
Bay does not serve as critical reproductive or foraging grounds for any
cetacean species.
Comment 16: AWL believes NMFS's analysis of small numbers
improperly conflates this criterion with the separate negligible impact
requirement of the statute. By defining small numbers to be relative to
the overall population, the criterion ends up being similar to the
negligible impact finding.
Response: We disagree with AWL's characterization of our analysis--
NMFS very clearly distinguishes our separate analyses for the small
numbers and negligible impact standards. As described in the proposed
rule (84 FR 24959, May 29, 2019), wherein the small numbers assessment
is based solely on the number of takes in relation to the abundance of
the stock (a purely numerical comparison), the negligible impact
analysis considers other factors, such as the nature of the anticipated
takes, the context of the exposures, the life history and vulnerability
of the individuals of different species, effects on habitat, the likely
effectiveness of mitigation, and the status of the affected stocks
(among other things) to determine if the takes will affect the fitness
of any individuals and, if so, whether the scale of any anticipated
impacts to reproduction or survivorship will adversely affect the
species or stock. For a fuller description of how NMFS conducts its
small numbers analysis, please see our final notice of issuance for
five IHAs for seismic surveys in the Atlantic (83 FR 63375, December 7,
2018).
Comment 17: AWL indicates that both NMFS's negligible impact
determination and its small numbers analysis ignore the impacts of oil
spills. Oil spills are an inevitable part of the Liberty project and
should be considered. NMFS ignores the impacts of oil spills in its
negligible impact and small numbers analysis by claiming that Hilcorp
has not requested authorization of takes from oil spills and oil spills
are not part of the ``specified activity'' for which NMFS is
authorizing takes. However, NMFS defines the ``specified activity'' as
the ``construct[ion] and operat[ion] of the LPDI, a self-contained
offshore drilling and production facility located on an artificial
gravel island.'' And as the Final EIS makes clear, small oil spills are
an inevitable part of the development and production and therefore
should be considered part of the ``specified activity'' for NMFS's
authorization.
Response: The Bureau of Safety and Environmental Enforcement (BSEE)
has primary regulatory authority related to safety and prevention of
pollution, including accidental oil spills, related to offshore oil and
gas operations. Pollution-prevention regulatory requirements for oil,
gas, and sulphur operations in the outer continental shelf are in 30
CFR part 250, subpart C, Pollution Prevention and Control. These
regulations require operators that engage in activities such as
exploration,
[[Page 70285]]
development, production, and transportation of oil and gas to take
measures to prevent unauthorized discharge of pollutants into offshore
waters (30 CFR 250.300). Operators shall not create conditions that
will pose unreasonable risks to public health, life, property, aquatic
life, wildlife, recreation, navigation, commercial fishing, or other
uses of the ocean. If pollution occurs that damages or threatens to
damage life (including fish and other aquatic life), property, any
mineral deposits in leased and unleased areas, or the marine, coastal,
or human environment, immediate corrective action must be taken and the
control and removal of the pollution must be to the satisfaction of
BSEE . These regulations further mandate that the operator conduct
inspections of drilling and production facilities daily, or at other
approved or prescribed intervals, to determine if pollution is
occurring (30 CFR 250.301). If problems are detected, necessary
maintenance or repairs must be made immediately.
BSEE and BOEM considered the potential risk of oil spills from the
LDPI project in the 2018 EIS. Based on BOEM and BSEE's oil spill
analysis in the EIS, the only sized spills that are reasonably likely
to occur in association with the LDPI operation are small spills
(<1,000 barrels (bbls)). Any crude oil spill would not occur prior to
drilling and operations, which are likely to begin in year 3 of the
effective period of the final rule. BOEM estimates about 70 small
spills, most of which would be less than 10 bbls, would occur over the
life of the Liberty Project, which is 25 years. Because the first 2
years of the project would not involve drilling, the time during which
spills could occur is limited to 23 years. Extrapolating this estimate
to the effective period of the rule and during a time at which spills
could occur (year 3-5), about 9 spills (70 spills/23 years * 3 years)
would be estimated to occur in the three years the rule is valid.
BOEM also explains in the EIS that spills are more likely to occur
when BOEM is conducting reservoir drilling, which is defined as initial
development drilling (as opposed to workovers, recompletions, and other
such well operations subsequently conducted on existing wells) beyond
the shoe (base) of the last casing string above the Kekiktuk Formation
(i.e. drilling that exposes the Kekiktuk Formation to an open, uncased
wellbore). Hilcorp is required by BOEM to limit reservoir drilling to
the ice-covered season. During the ice-covered season, any spill would
be contained by the ice and hence have limited impact on marine
mammals. Limiting reservoir drilling to solid ice conditions (defined
as 18 inches of ice in all areas 500 feet of the LDPI) limits the risk
of an oil spill and hence limits potential impacts on pinnipeds (note
cetaceans are not present and therefore unaffected by any spills during
the ice-covered season).
During the open-water season, when both cetaceans and pinnipeds
could be subjected to an oil spill (albeit in low abundance), BOEM
anticipates that small refined spills that reach the open water would
be contained by booms or absorbent pads; these small spills would also
evaporate and disperse within hours to a few days. A 3 bbl refined oil
spill during summer is anticipated to evaporate and disperse within 24
hours, and a 200 bbl refined oil spill during summer is anticipated to
evaporate and disperse within 3 days (BOEM 2017a).
In summary, as described in the EIS, BOEM and BSEE evaluated the
potential for impacts from oil spills and concluded that any potential
oil spills are likely to be small, and there are measures set in place
to minimize impacts of any potential spill on environmental resources,
including marine mammals. For purposes of this rulemaking, NMFS
discussed the potential risk of oil spills in its proposed rule (84 FR
24946; May 29, 2019), but as noted in the proposed rule, the MMPA
authorizes NMFS to issue take from otherwise legal activities, of which
oil spills are not, and therefore, NMFS cannot authorize, and is not
authorizing, takes of marine mammals incidental to oil spills in the
final rule.
Comment 18: AWL believes NMFS ignores the additive effects from
other oil and gas activities in the Arctic and climate change. AWL
asserts NMFS fails to consider whether the impacts of the Liberty
project will be negligible in light of ongoing and future oil and gas
development in the Beaufort Sea and NPR-A, including the Endicott and
Northstar projects and Colville Delta 5 (CD-5), Greater Mooses Tooth
(GMT) 1 and 2, and Willow project in the NPR-A, among others. AWL
states the Liberty project will emit greenhouse gases and exacerbate
the climate change that is threatening the continued existence of these
species through habitat destruction. AWL claims NMFS's negligible
impact determination fails to consider such impacts.
Response: The MMPA requires NMFS to allow, upon request, the
incidental take of marine mammals related to the specified activity,
which we have identified as the first five years of LDPI construction
and operation. The additive effects from other oil and gas activities
in the Arctic and climate change are not part of that specified
activity, although the potential for them is discussed in the proposed
rule and their ongoing influence is considered through their
incorporation into the baseline for our analysis (e.g., through the
regulatory status of the species, marine mammal densities, and
population trends). Further, these factors are considered in NMFS'
Biological Opinion (section 5.0) and environmental analysis required
under the National Environmental Policy Act (NEPA). In the Biological
Opinion, all relevant future climate-related environmental conditions,
such as those caused by the projects AWL acknowledges, in the action
area are described in the environmental baseline. BOEM's EIS, on which
NOAA was a cooperating agency and which NMFS adopted for issuance of
the final rule, identifies the potential impacts of the additive
effects from other oil and gas activities in the Arctic and climate
change on the human environment, including marine mammals. The effects
of ongoing and future oil and gas projects in the Arctic, as well as
climate change, are all included in BOEM's cumulative impact analysis
in the EIS.
Comment 19: AWL believes the proposed activities will adversely
affect Nuiqsut's subsistence activities, including seal and bowhead
whale hunting, and these impacts may not be mitigable. AWL asserts
NMFS's proposed rule is inadequate because it fails to ensure that the
proposed activity will not have an unmitigable adverse impact on
Nuiqsut's subsistence harvest of bowhead whales. AWL argues
construction and operation may cause: ``(1) deflection of whale
movements farther offshore, (2) interference from support vessels, (3)
avoidance of the Proposed Action Area by Nuiqsut whalers due to the
presence of the proposed LDPI and production facilities and potentially
contaminated resources, (4) whaling conflicts with summer construction
activities such as sheet pile driving (i.e., LDPI slope protection),
and (5) oil spills.'' AWL also asserts that even if there are whales
available near the proposed LDPI, Nuiqsut whalers will likely avoid the
area and if whalers avoid the proposed LDPI site in such years their
``opportunities to strike whales could be severely reduced for one or
more seasons . . . resulting in major impacts to subsistence whaling
for Nuiqsut.'' AWL also argues that if there were to be a large oil
spill from the proposed LDPI, communities across the North Slope would
suffer. AWL asserts NMFS' explanation of its subsistence finding cites
consultation and mitigation without explaining how
[[Page 70286]]
these measures will address the specific adverse impacts of the
proposed activity on subsistence activities. AWL believes NMFS's
proposed rule is therefore inadequate because NMFS has not demonstrated
that the proposed activity will not have an unmitigable adverse impact
on subsistence activities.
Response: AWL makes a number of assumptions that are unsupported
and contradictory to NMFS' analysis of the potential impact on
subsistence use of marine mammals. Importantly, the North Slope Borough
(NSB) raised no significant concerns with the project and both the
NSB's and AEWC's comment letters on the project commended Hilcorp for
its outreach and commitment to the CAA during the rulemaking process.
The proposed project would not deflect whale movement father offshore
because the acoustic footprint of the project within which we would
expect any disruption of behavioral patterns (e.g., avoidance) is
almost entirely confined to within Foggy Island Bay, where bowhead and
gray whales do not migrate. In addition, BOEM has included a condition
in Hilcorp's permit to minimize interference with subsistence whaling
near Cross Island, wherein all pipe- and pile-driving activities and
support vessel traffic outside the barrier islands will cease by August
1 and not resume until the official end of the hunt or until the quota
has been met, whichever occurs first. This mitigation measure is
carried over to this final rule. AWL's assumption that whalers would
avoid the area on their own is unfounded and unsupported. NSB and AEWC
did not raise this concern and, in contrast to AWL's assumption,
requested Hilcorp to allow whalers to use the LDPI for safe harbor
during the whaling season. Access to the LDPI by subsistence users was
a mitigation measure included in the proposed rule and is included in
the final rule to ensure the specified activities do not have an
unmitigable adverse impact on subsistence users. In the unlikely event
of a large oil spill, impacts could reach both marine mammal and
subsistence communities, as with any large oil spill in the Arctic;
however, as described in the response to Comment 17 above, large oil
spills are neither anticipated during the course of this 5-year rule
nor part of Hilcorp's specified activity, and NMFS is not authorizing
takes of marine mammals incidental to oil spills. Further, BOEM and
BSEE are responsible for permitting the construction and operation of
the LDPI and for Hilcorp's oil spill response plan, respectively, not
NMFS.
Comment 20: AWL believes NMFS has failed to implement measures that
would effect the least practicable impact on marine mammals, by
requiring mitigation measures that are unclear or ineffective, and by
failing to adopt additional mitigation measures. AWL states that NMFS
must clarify in the final rule that the shutdown zone is coextensive
with the Level A harassment zone.
Response: The Level A harassment threshold distances and ensonified
areas are identified in the proposed and final rule. As described in
our response to Comment 7 above, which responds to the Commission's
comment on this matter, the Level A harassment zone equates to the
shutdown zone for gray whales and bowhead whales, and pile-driving
cannot commence or continue if a gray whale or bowhead whale is seen
within or approaching that zone; if a mid-frequency cetacean (beluga)
or pinniped (seal) enters the Level A harassment zone during pile
driving, Hilcorp could complete setting the pile but not initiate
additional pile driving of new piles until the marine mammal has left
and is on a path away from the Level A harassment zone. Hilcorp is also
required to implement a number of mitigation measures that would
minimize impacts to marine mammals through both the BOEM permitting
process and the final rule as well as throughout their own construction
methodology proposals. These include scheduling island construction
during the ice-covered season, minimizing impact pile driving, avoiding
pile driving during the bowhead whale migration period, reservoir
drilling during solid ice conditions, using pile driving ramp-ups, and
implementing the aforementioned shut down zones. Hilcorp, in
coordination with NMFS and in consideration of the public comments on
the proposed rule, has also clarified measures in the ice-road BMPs
which must be followed per the final rule. AWL discussed concerns with
monitoring but did not propose any specific additional mitigation
measures. After evaluating all of the applicable information, NMFS has
concluded that the required mitigation measures will effect the least
practicable adverse impact on the affected marine mammal species and
stocks and their habitat.
Comment 21: AWL believes NMFS relies on visual monitoring (or
lookouts) and other mitigation measures for marine mammals proposed by
Hilcorp that are known to be ineffective and inadequate to protect the
species at issue. AWL states that in Conservation Council for Hawaii v.
National Marine Fisheries Service, the court determined that NMFS may
not choose the lesser mitigation option of lookouts to protect marine
mammals (in that case from military sonar), especially knowing that
many potential disruptions to marine mammal behavior will be difficult
to detect or avoid through lookouts. AWL asserts that, here, NMFS
should require Hilcorp to deploy long-term acoustic monitors consistent
with the recommendations of the peer-review panel in order to obtain
data both on the presence of marine mammals and sound levels generated
during pile driving activities. AWL acknowledges NMFS is requiring
Hilcorp to collect measurements using hand-held hydrophones lowered in
a hole drilled through the ice during pile driving activities; however,
AWL feels that, while this option would at least collect some noise
monitoring data during the ice-covered season, the peer-review panel
noted that it is only feasible in shallower water and would cover a
much shorter time frame than acoustic recorders deployed before the
start of winter.
Response: Hilcorp is required to abide by marine mammal mitigation
measures NMFS consistently requires in pile driving incidental take
authorizations, as they are considered effective at minimizing the
impact to marine mammals. While Hilcorp is relying on visual monitoring
to detect marine mammals, they are implementing an unmanned aircraft
system (UAS) monitoring program that will allow detection farther than
island-based observers can monitor. Hilcorp is also conducting acoustic
monitoring in accordance with the peer-review panel's recommendations,
which will aid in long-term detection analysis. The peer-review panel
specifically recommended Hilcorp deploy acoustic recorders during ice-
covered periods to obtain data on both the presence of marine mammals
and the sound levels generated during pile driving activities.
Deployment of autonomous, long-term recorders during winter is not
practicable as recorders, and the data housed within them, would likely
be lost to sea ice. AWL did not offer alternative methods of recording
during winter; therefore, absent any new information, the peer-review
panel's recommendation has been adopted and satisfied.
Comment 22: AWL also notes that the peer-review panel encouraged
Hilcorp to consider deployment of additional acoustic recorders during
the open-water season approximately 15 km northwest of the project area
to facilitate a broader, multi-year approach to analyzing the effect of
sound exposure on marine mammals by various LDPI
[[Page 70287]]
and non-LDPI sources. AWL believes it is not clear that Hilcorp's
proposal to position recorders at unspecified ranges from the project
activities will capture the same level of sound exposure on marine
mammals from multiple known sources. AWL argues the final rule must
incorporate the peer review panel's monitoring recommendations or
otherwise ensure that this exposure is measured.
Response: Hilcorp's Acoustic Monitoring Plan, dated December 24,
2018, and their 4MP, dated February 12, 2019, and made available during
the public comment period, explain that the recorder arrangement will
be configured each year based on the anticipated activities for that
season and the modelled sound propagation estimates for the relevant
sources. This approach will provide for the most effective and relevant
monitoring each year, and makes a set location unnecessary. The
recorders will be onsite during each season and placed to provide data
on ambient noise conditions and characterize or verify the long-range
propagation of sounds emanating from the LDPI during construction
activities at an offshore location. As such, AWL's concern, as well as
the peer-review panel's recommendation, are satisfied because the
recorders will provide long-term data sets in both the near and far
fields.
Comment 23: AWL notes that the proposed rule requires
implementation of BMPs to avoid and minimize ice seal and habitat
disturbance during ice road construction, maintenance, and use. AWL
claims, however, that the ice road BMPs fail to reflect the best
available science and information and thus may not minimize the impacts
of these activities on seals.
Response: The ice road BMPs, developed in consultation with Hilcorp
and NMFS' leading ice seal biologist, are specifically designed to
minimize impacts to ringed seals. NMFS Office of Protected Resources
(OPR) and Alaska Region (AKR) closely coordinated with the leading ice
seal experts in our Alaska Fisheries Science Center (AFSC) to better
understand the new, best available science regarding how ice seals use
ice roads (e.g., how ice road construction can lead to fissures
conducive to constructing lairs on the outer edges, general distances
from the shoulder where lairs have been found) and detection methods.
During development of the BMPs, we investigated detection methods such
as the previous requirement to use specially trained dogs and infrared
(IR) imagery. AFSC found that IR failed to detect seals in lairs. AFSC
also previously investigated the success of using ground penetrating
radar over known lairs in order to see whether there was a reliable
thermal signal. Ground penetrating radar was not found to be a useful
tool in this regard either. The use of trained dogs was also
questionable as there was concern over the cost/benefit ratio of
effectiveness versus the trace of dog scent potentially attracting
polar bears to actively used ice seal structures, but more relevant is
the fact that there are currently no trained dogs available. NMFS
considered this and other new information obtained during ice road
investigations from Northstar to develop a suite of practicable
mitigation measures to implement during ice road construction for the
Liberty project. Those BMPs reflect the best available science and
minimize the impact of the work on ringed seals. Harassment that cannot
be avoided through this comprehensive suite of mitigation measures may
be authorized in LOAs pursuant to this final rule.
Comment 24: AWL states that the BMPs assume that seals will avoid
the area on their own because of the construction activity, and NMFS
should support this assumption with reference to monitoring and
reporting information related to the extensive previous ice road
construction and use in seal habitat on the North Slope.
Response: Although AWL did not provide the language in the ice road
BMPs to which they are referring, we assume it is the statement,
``Prior to establishing lairs, ringed seals are mobile and are expected
to generally avoid the ice roads/trails and construction activities.''
In our proposed rule (84 FR 24939; May 29, 2019), we discuss how ice
seals utilize and may be attracted to ice roads as the construction of
such roads tends to create cracks in the ice along the edges. Cracks
and thinned ice, occurring either naturally or adjacent to ice roads,
are easily exploitable habitat for ringed seals. We supplement that
discussion with data from Williams et al. (2006), which compiles
monitoring efforts during construction and operation of the Northstar
drilling island and the two recent ice seal encounters on ice roads
recently reported (voluntarily) by Hilcorp and another industry
company. While NMFS has determined that the mitigation and monitoring
measures contained in the BMP document support our least practicable
adverse impact determination and has included them in these final
regulations, the BMP document itself was drafted by Hilcorp, and NMFS'
does not necessarily support every statement contained therein.
Comment 25: AWL notes that if a seal is observed within 150 feet of
an ice road or trail, BMP 6 requires the observer to alert Hilcorp's
Environmental Specialist, who will then monitor the seal until it is no
longer within 150 feet of the road. The AWL believes disruptive
activities may simply continue while the seal is within the monitoring
buffer, and that the final rule should ensure a sufficient buffer area
to avoid disturbance to seals during the pre-March 1 construction
season.
Response: The 150 ft distance referenced by AWL refers to a
monitoring area. As described in response to comment #10, corrections
and clarifications were made to the original BMPs and proposed rule to
clearly state that ice road construction and maintenance activities
will avoid a seal structure by 150 m and a seal by 50 m on ice roads
regardless of time of year. Therefore, AWL's assumption that activities
could simply continue without action prior to March 1 is erroneous. The
final rule and final ice road BMPs clarify this requirement
Comment 26: AWL is concerned that after March 1, the BMPs call for
daytime observation of seals and lairs every other day when activity
occurs on ice roads or trails and, unlike other observers noted in
Hilcorp's Marine Mammal Monitoring and Mitigation plan (4M plan), these
observers need not be certified Protected Species Observers (PSOs). AWL
believe it is unclear why PSO certification is not required and why the
observations only occur every other operation day instead of all days
of operation. AWL asserts the final rule and BMPs should require
observers to be PSO certified and present on all days of operation, or
explain why this would not constitute a best practice.
Response: Prior to the initiation of sea ice road- and ice trail-
related activities, project personnel associated with ice road
construction, maintenance, use or decommissioning (i.e., ice road
construction workers, surveyors, security personnel, and the
environmental team) will receive annual training on mitigation and
monitoring measures. In addition to mitigation and monitoring measures,
annual training includes: Ringed Seal Identification and Brief Life
History; Physical Environment (habitat characteristics and how to
potentially identify habitat); Ringed Seal Use in the Ice Road Region
(timing, location, habitat use, birthing lairs, breathing holes,
basking, etc.); Potential Effects of Disturbance; Importance of Lairs,
Breathing Holes and Basking to Ringed Seals; and a Summary of
Regulatory Requirements (i.e., MMPA and the Endangered Species Act
(ESA)).
[[Page 70288]]
Monitoring for ringed seals along the ice road is a considerably
simpler task than observing for several species of seal in open water
and this training will be sufficient to ensure that any seals within
the monitoring zone are recorded. In 2018, Hilcorp reported zero seal
observations along the Northstar ice roads. To ensure safe travel, it
is important to limit the number of vehicles traveling ice roads.
Therefore, for safety reasons and due to the low likelihood of
observing seals within the monitoring zone, conducting monitoring every
other day will be sufficient to record seals that may occur. In
addition, as described in response to the next comment, the dedicated
observer is not the single source of reporting. Any seals observed by
drivers or workers, both day and night, are also required to report the
sighting to Hilcorp's environmental coordinator.
Comment 27: AWL asserts that seal lairs are difficult to detect,
and NMFS should require more vigorous efforts to detect them, for
example, that the BMPs should require operators to employ trained dogs
or thermal imaging techniques along the ice road routes to better
support a conclusion that there are no lairs present. AWL states the
Open Water Review Panel specifically recommended that NMFS investigate
the viability of these and other potential detection methods. AWL
asserts employing observers working only in daylight hours, only after
March 1, only every other day of operation, and only equipped with
their eyesight does not appear to constitute a best practice.
Response: See response to Comment 23 regarding the use of trained
dogs and thermal imaging as detection methods. As for the use of
observers every other day during daylight hours, NMFS believes this is
an appropriate amount of coverage because the dedicated observer is not
the single source of reporting. Any seals observed by drivers or
workers, both day and night, are also required to report the sighting
to Hilcorp's environmental coordinator. In addition, we provide
subsequent justification of adequate monitoring in response to comment
#26 above. Observers would be equipped with binoculars so AWL is
incorrect in their assertion that only the naked eye would be used.
Comment 28: AWL believes BOEM's FEIS is inadequate in numerous
respects, does not fully cover the scope of NMFS's proposed rule, and
does not consider alternatives to the proposed rule, and therefore,
NMFS cannot satisfy its obligations under NEPA by adopting BOEM's FEIS.
They assert that the EIS fails to (1) provide meaningful disclosure and
analysis of Liberty's contribution to greenhouse gas pollution and
climate change; (2) accurately and thoroughly assess the likelihood and
potential impacts of a significant oil spill; (3) take a hard look at
Liberty's impacts on marine mammals and other species; (4) adequately
consider the project's effects on subsistence and its disproportionate
effect on environmental justice communities; (5) consider the
cumulative effects of the project in combination with all past,
present, and reasonably foreseeable actions; and (6) disclose and
consider Hilcorp's track record of spills, accidents, and regulatory
violations.
Response: Section 2.2.11 of BOEM's Liberty Drilling and Production
Plan EIS clearly explains NMFS' permitting role in the Liberty project.
The EIS states that given the widespread presence of several species of
marine mammals in the Beaufort Sea and the nature of oil and gas
production facility construction and, potentially, operational
activities, there is the potential that some activities associated with
Hilcorp's LDPI may result in the take of marine mammals incidental to
the introduction of noise into the marine environment and ice road
construction activities. Because of the potential for these activities
to take marine mammals, Hilcorp has submitted an Incidental Take
Authorization (ITA) application to NMFS. NMFS provided extensive
comments to BOEM on the draft and final EIS to strengthen their
analysis of marine mammal impacts in consideration of Hilcorp's request
for the authorization to take marine mammals incidental to construction
and operation of the LDPI. The EIS describes NMFS' action and no action
alternatives, which include issuing the requested incidental take
authorization and denying the requested incidental take authorization,
respectively. As for the six topical areas AWL raises, the FEIS
addresses all of these. The bulk of the EIS is dedicated to discussing
the impacts on the human environment from small and very large oil
spills (Chapter 4), and Chapter 5 is dedicated solely to a cumulative
effects assessment. Greenhouse gases emission from the LDPI are
quantified in Chapter 4 (e.g., Table 4-6 in BOEM's EIS) and climate
change impacts on marine mammals are addressed in Chapter 4 (e.g.,
Section 3.2.4.6.6) and Chapter 5 (e.g., section 5.1.3). The impacts of
the LDPI on marine mammals is also thoroughly discussed in Chapter 4
which includes both construction and operation analysis. Subsistence
uses and potential impacts are described throughout the document
relative to each resources and are summarized in Table ES-1. The EIS
does not discuss Hilcorp's previous environmental compliance record;
however, as described in response to Comment #38, this is beyond the
scope of NMFS' action and inclusion in the EIS is not required for us
to adopt the EIS for purposes of issuing the regulations.
Comment 29: AWL notes that NMFS considered new information provided
by Hilcorp that was not covered in the EIS. Specifically, on February
4, 2019, Hilcorp provided ``details on a previously undescribed
component of the project (installation of foundation piles in the
interior of the LDPI), and revised marine mammal density and estimated
take numbers.'' AWL believes this additional information could affect
the agency's analysis of the effects of the project on marine mammals.
Response: Foundation piles are described in BOEM's EIS on pages 2-
12 and, as described in the proposed rule, the installation of
foundation piles was found to result in very low noise levels,
equivalent to driving conductor pipe piles. Given these piles are
driven on the interior of the island, there is no potential for Level A
harassment and the Level B harassment isopleth extends only 315 m from
the island. Therefore, the potential for take is very limited. The EIS
does not contain take estimates, and therefore, despite specific
details and the very small amount of additional take for foundation
pile installation being absent from the EIS, the information would not
alter the analysis in the EIS. Requirements under NEPA are separate
from those required to issue an MMPA incidental take authorization, and
NMFS has satisfied the requirements for both statutes in issuing this
final rule.
Comment 30: AWL asserts that BOEM's FEIS does not consider
alternatives to NMFS's proposed rule. AWL believes NMFS must consider a
no action alternative, under which NMFS would deny Hilcorp's request
for incidental take authorization, as well as alternatives that would
further reduce harm to marine mammals, such as prohibiting construction
activity during the open-water season, requiring Hilcorp to cease pile
driving if an ice seal is seen in the area, requiring the use of long-
term acoustic monitors, or requiring all vessels associated with the
Liberty project to travel at no more than 10 knots.
Response: As described above, BOEM's FEIS included NMFS' action and
no action alternatives, which are, respectively, to issue the requested
incidental take authorization, with
[[Page 70289]]
required mitigation measures, or to deny the requested incidental take
authorization. Both the EIS and/or NMFS' regulations include a suite of
mitigation measures to reduce adverse impacts to marine mammals,
including no pile driving just before and during the bowhead whale
hunt, long-term acoustic monitoring, and vessel speed restrictions
where appropriate. These measures were included in both the FEIS and
the final rule. Hilcorp will also minimize disturbance to ice seals
through the incorporation of mitigation measures such as ramp-up. We
have authorized Level A harassment and Level B harassment for ice
seals, however; therefore, Hilcorp is not required to cease pile
driving should a seal be observed in the area, as suggested by the AWL.
Comment 31: The NSB requested the regulations require Hilcorp to
participate in the annual in-person peer review sponsored by NMFS for
companies operating in areas subject to marine mammal subsistence
harvest and to annually meet with Borough representatives to discuss
the results and findings from Hilcorp's Marine Mammal Mitigation and
Monitoring Plan. The AEWC similarly recommended findings from the
mitigation and monitoring plan be reviewed annually by NMFS.
Response: Hilcorp is required to submit annual monitoring reports
to NMFS in a timely manner. NMFS conducts peer-review panels when
activities are proposed in Arctic waters, and whether the meetings are
in-person or virtual depends on the level of expected activity
necessitating MMPA authorization and the availability of travel
resources for NMFS staff. For the LDPI, NMFS will provide the NSB and
the public all of Hilcorp's annual monitoring reports as well as any
interim reports (e.g., initial acoustic monitoring reports) for their
review. Throughout the life of the regulations, NMFS will engage with
Hilcorp as well as the NSB to address any deficiencies or issues with
those reports. In addition, Hilcorp has committed to participating in
the annual peer-review panel, of which NSB is an invitee, to discuss
data collected during marine mammal and acoustic monitoring as a means
to carry out this coordination.
Comment 33: The NSB recommends the regulations prohibit any pile
driving during, and two weeks prior to, the whale hunting season in
Nuiqsut, unless Hilcorp can conclusively demonstrate that such
vibratory pile driving does not alter the migratory paths of bowheads.
Response: Per the BOEM permit conditions, Hilcorp shall cease all
pipe- and pile- driving by August 1, annually, and not resume until the
end of the official hunt season or if subsistence users have met the
whale quota. This mitigation measure is included in the final rule.
Comment 34: The AEWC commended Hilcorp for keeping the AEWC
informed throughout their planning process for Liberty, their
commitment to continuing their participation in the Open Water Season
Conflict Avoidance Agreement (CAA) and the Annual CAA Process, and
expressed their appreciation for Hilcorp's work with the AEWC, the
community of Nuiqsut, and the North Slope Borough.
Response: NMFS will work with Hilcorp throughout the life of the
regulations to support communication and coordination with the AEWC,
the community of Nuiqst, and the NSB continues.
Comment 35: Several members of the public opposed drilling due to
the potential for an oil spill.
Response: NMFS' authority and these final regulations allow for
issuance of a Letter of Authorization to authorize takes of marine
mammals incidental to island construction and operation. NMFS has no
authority over whether this project, or any other drilling, is
permitted. BOEM is the entity responsible for deciding whether to
permit the project.
Comment 36: One commenter was concerned about polar bear impacts
and discussed incidental take permit requirements for this species.
Response: Polar bears, and any permit related to the taking of
polar bears under the MMPA or ESA, fall within the jurisdiction of the
U.S. Fish and Wildlife Service. Therefore, this comment is outside
NMFS' authority and the scope of the rulemaking.
Comment 37: One commenter urged review of the drilling plan for oil
spill protection and earthquake contingencies and indicated that if a
Deepwater Horizon event occurred in the Beaufort Sea, it would take
decades to recover.
Response: NMFS remains interested in reviewing Hilcorp's oil spill
response plan and, as indicated on page 24946 of the proposed rule, we
have proactively engaged with BSEE (the Federal agency charged with
reviewing and approving Hilcorp's oil spill response plan) and
recommended measures to be included in the oil spill response plan.
BSEE has indicated that NMFS will have an opportunity to review the oil
spill response plan once they receive all the information necessary to
move forward with their process.
Comment 38: One commenter had concerns about Hilcorp's ability to
build and manage the project. Their concerns stem from an incident
earlier this year when Hilcorp's underwater gas pipeline in Alaska's
Cook Inlet leaked for nearly four months because the company said the
presence of sea ice prevented its repair.
Response: NMFS' authority and these final regulations allow for
issuance of a Letter of Authorization to authorize takes of marine
mammals incidental to island construction and operation. BOEM and BSEE
have authority over the permitting of the project and Hilcorp's oil
spill response plan, respectively; therefore, this comment is beyond
the scope of NMFS's authority under this rulemaking.
NMFS notes, however, that Cook Inlet presents different ice
conditions than the Arctic where the Liberty project is to be located.
Ice roads are not constructed in Cook Inlet which limited response
capabilities. However, in the Arctic, ice roads and thick sea ice allow
for other means of spill response. As analyzed by BOEM, the
effectiveness of cleanup operations is highly dependent on volume,
location, and time of year in Alaska. A small spill occurring during
winter on solid ice and snow can be readily cleaned up using
conventional land-based equipment such as shovels, snow blowers, and
bulldozers, resulting in a near 100% recovery rate. In the event of a
winter blowout, response methods would be similar to those employed on
shore. Instead of using boats and skimmers to mount a response,
responders would utilize front-end loaders, bulldozers, vacuum trucks,
dump trucks, and front-end mounted ice trimmers to collect and remove
the oil contaminated snow and ice. To facilitate response, ice roads
would have to be constructed to adequately support the equipment and
maintain safe operating conditions. In addition to heavy equipment,
response operations would also include the use of snow blowers,
shovels, and snow machines/ATVs with sleds to collect and remove the
oil. In situ burning would also be utilized to remove oil from the ice
surface. A release in solid ice conditions is easier to respond to
because ice contains oil, limiting its dispersal into the marine
environment.
Comment 39: One commenter recommended the LDPI project should not
be implemented until further technology can promise this project will
not impact the ocean negatively.
Response: Under the MMPA, NMFS must evaluate each request for an
incidental take authorization on the merits of the application and the
specified activity. Here, NMFS is not authorizing the take of marine
mammals
[[Page 70290]]
from activities other than island construction and operation for 5
years. NMFS found, through a robust analysis of the potential effects
of these activities on marine mammals and their habitat, that: The
specified activities would have a negligible impact on the affected
species and stocks and would not have an unmitigable adverse impact on
subsistence uses, and; that the prescribed mitigation measures would
effect the least practicable adverse impact on such species and stocks.
NMFS has no authority to delay issuance of an ITA if the findings
described above are made.
Comment 40: One commenter recommended the project should not be
allowed to proceed unless it does not harm or kill marine life.
Response: NMFS does not issue permits to construct and operate the
LDPI (i.e., allow or not allow the underlying activity). NMFS issues
authorization to take marine mammals incidental to the specified
activity. The MMPA prohibits, with certain exceptions, the take of
marine mammals. However, the MMPA allows, upon request, the incidental,
but not intentional, taking of small numbers of marine mammals by U.S.
citizens who engage in a specified activity within a specified
geographic region. Hilcorp applied for an incidental take authorization
in accordance with the MMPA and its implementing regulations and NMFS
followed the required process in promulgating incidental take
regulations. Accordingly, NMFS is issuing regulations and will issue an
LOA authorizing the take of marine mammals incidental to the
construction and operation of the LDPI in accordance with the MMPA.
Comment 41: One commenter was concerned that allowing Hilcorp to
harass and harm belugas, possibly resulting in their deaths, would
decrease the beluga population in that area, and that this population
would also not be able to recover losses. The commenter referred to the
Cook Inlet beluga whale population status and lack of recovery after
subsistence hunting was restricted as justification for the comment.
Response: The commenter believes the specified activities would
result in beluga whale mortality and inappropriately compares a very
small, isolated and critically endangered stock of beluga whales in
Cook Inlet to a robust, far-ranging, non-ESA listed, stock in the
Arctic. The final rule does not authorize any mortality or serious
injury of beluga whales incidental to the construction and operations
of the LDPI and NMFS does not believe any would potentially occur. The
population of the Beaufort Sea stock of beluga whales is estimated at
39,258 individuals (compared to the Cook Inlet beluga whale stock of
327 whales) and has a much greater habitat range than Cook Inlet
belugas. Any harassment to belugas in Foggy Island Bay incidental to
pile driving or operations (e.g., drilling) would be very limited, as
pile driving would primarily occur during the ice-covered months when
beluga whales are not present and, if any belugas are present during
any pile driving or drilling activity, that activity would only impact
a very small number of whales, as Foggy Island Bay is not heavily used
by cetaceans, including beluga whales.
Comment 42: One commenter believed Hilcorp's activity may also
affect the salmon populations upon which endangered whales depend and
that allowing Hilcorp to take even a small number of protected animals
will result in a psychological acceptance of harming these creatures
and thus lead to even more animals being harmed.
Response: The potential impacts to marine mammal prey from the LDPI
are evaluated in a number of assessments including the proposed rule,
ESA section 7 consultation completed for issuance of the rule (see NMFS
Biological Opinion issued August 30, 2019), and BOEM's EIS. Those
assessments determined the LDPI would have a minimal impact on marine
mammal prey, given, among other things, the LDPI's location outside
critical foraging habitats and implementation of measures designed to
reduce impacts to marine mammals and their habitat, including prey. The
regulations, issued pursuant to the MMPA, allow the taking of marine
mammals incidental to the specified activity. NMFS evaluates and, if
appropriate, issues an ITA based on the information contained within an
ITA application and the best available science. The take authorized is
limited to the 5-year period the regulations are effective.
Description of Marine Mammals in the Area of the Specified Activity
Sections 3 and 4 of the application summarize available information
regarding status and trends, distribution and habitat preferences, and
behavior and life history of the potentially affected species.
Additional information regarding population trends and threats may be
found in NMFS' Stock Assessment Reports (SARs; https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-
stock-assessments), and more general information about these species
(e.g., physical and behavioral descriptions) may be found on NMFS'
website (www.nmfs.noaa.gov/pr/species/mammals/). Additional information
may be found in BOEM's Final EIS for the project which is available
online at https://www.boem.gov/Hilcorp-Liberty/.
Table 2 lists all species with expected potential for occurrence in
Foggy Island Bay and the surrounding Beaufort Sea and summarizes
information related to the population or stock, including regulatory
status under the MMPA and ESA and potential biological removal (PBR),
where known. For taxonomy, we follow Committee on Taxonomy (2016). PBR
is defined by the MMPA as the maximum number of animals, not including
natural mortalities, that may be removed from a marine mammal stock
while allowing that stock to reach or maintain its optimum sustainable
population (as described in NMFS' SARs). PBR and annual serious injury
and mortality from anthropogenic sources are included here as gross
indicators of the status of the species and other threats.
Marine mammal abundance estimates presented in this document
represent the total number of individuals that make up a given stock or
the total number estimated within a particular study or survey area.
NMFS' stock abundance estimates for most species represent the total
estimate of individuals within the geographic area, if known, that
comprises that stock. For some species, this geographic area may extend
beyond U.S. waters. All managed stocks in this region are assessed in
NMFS' U.S. 2017 SAR for Alaska (Muto et al., 2018). All values
presented in Table 2 are the most recent available at the time of
publication and are available in the 2017 SARs (Muto et al., 2018).
[[Page 70291]]
Table 2--Marine Mammals With Expected Potential Occurrence in Beaufort Sea, Alaska
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ESA/ MMPA status; Stock abundance (CV,
Common name Scientific name Stock strategic (Y/N) Nmin, most recent PBR Annual M/
\1\ abundance survey) \2\ SI \3\
--------------------------------------------------------------------------------------------------------------------------------------------------------
Order Cetartiodactyla--Cetacea--Superfamily Mysticeti (baleen whales)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Family Eschrichtiidae:
Gray whale...................... Eschrichtius robustus.. Eastern North Pacific.. -;N 20,990 (0.05, 20,125, 624 132
2011).
Family Balaenidae:
Bowhead whale................... Balaena mysticetus..... Western Arctic......... E/D; Y 16,820 (0.052, 16,100, 161 46
2011).
Humpback whale.................. Megaptera novaeangliae) Central North Pacific E/D; Y 10,103 (0.3, 7,891, 83 26
Stock. 2006).
Minke whale..................... ....................... Alaska................. -;N unk................... undet. 0
Fin whale....................... ....................... Northeast Pacific...... E/D; Y 3,168 (0.26, 2,554, 5.1 0.6
2013)\6\.
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Superfamily Odontoceti (toothed whales, dolphins, and porpoises)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Family Delphinidae:
Beluga whale.................... Delphinapterus leucas.. Beaufort Sea........... -; N 39,258 (0.229, N/A, Und. 139
1992).
Eastern Chukchi........ -; N 20,752 (0.70, 12,194, 244 67
2012).
Killer whale.................... Orcinus orcas.......... Eastern North Pacific -;N 587 (n/a, 587, 2012).. 5.9 0
Gulf of Alaska,
Aleutian Islands, and
Bering Sea Transient.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Order Carnivora--Superfamily Pinnipedia
--------------------------------------------------------------------------------------------------------------------------------------------------------
Family Otariidae (eared seals and
sea lions):
Steller sea lion................ Eumatopias jubatus..... Eastern U.S............ -; N 41,638 (-, 41,638, 2,498 108
2015).
Western U.S............ E/D;Y 53,303 (-, 53,303, 320 241
2016).
Family Phocidae (earless seals):
Ringed Seal..................... Pusa hispida........... Alaska................. T, D; Y 170,000 (-, 170,000, Und. 1,054
2012) \4\.
Bearded seal.................... Erignathus barbatus.... Alaska................. T, D; Y 299,174 (-, 273,676) Und. 391
\5\.
Spotted seal.................... Phoca largha........... Alaska................. .................. 423,625 (-, 423,237, 12,697 329
2013).
Ribbon seal..................... Histriophoca fasciata.. Alaska................. .................. 184,000 (-, 163,086, 9,785 3.9
2013).
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Endangered Species Act (ESA) status: Endangered (E), Threatened (T)/MMPA status: Depleted (D). A dash (-) indicates that the species is not listed
under the ESA or designated as depleted under the MMPA. Under the MMPA, a strategic stock is one for which the level of direct human-caused mortality
exceeds PBR or which is determined to be declining and likely to be listed under the ESA within the foreseeable future. Any species or stock listed
under the ESA is automatically designated under the MMPA as depleted and as a strategic stock.
\2\ NMFS marine mammal stock assessment reports online at: www.nmfs.noaa.gov/pr/sars/. CV is the coefficient of variation; Nmin is the minimum estimate
of stock abundance.
\3\ These values, found in NMFS' SARs, represent annual levels of human-caused mortality plus serious injury from all sources combined (e.g.,
subsistence use, commercial fisheries, ship strike). Annual M/SI often cannot be determined precisely and is in some cases presented as a minimum
value or range. A CV associated with estimated mortality due to commercial fisheries is presented in some cases.
\4\ The population provided here was derived using a very limited sub-sample of the data collected from the U.S. portion of the Bering Sea in 2012 (Conn
et al., 2014). Thus, the actual number of ringed seals in the U.S. sector of the Bering Sea is likely much higher, perhaps by a factor of two or more
(Muto et al., 2018). Reliable estimates of abundance are not available for the Chukchi and Beaufort seas (Muto et al., 2018).
\5\ In the spring of 2012 and 2013, surveys were conducted in the Bering Sea and the Sea of Okhotsk; these data do not include seals in the Chukchi and
Beaufort Seas at the time of the survey.
\6\ NBEST, NMIN, and PBR have been calculated for this stock; however, important caveats exist. See Stock Assessment Report text for details.
Note Italicized species are not authorized to be taken.
All species that could potentially occur in the Beaufort Sea are
included in Table 2. However, the temporal and/or spatial occurrence of
minke, fin, humpback whales, killer whales, narwhals, harbor porpoises,
and ribbon seals are such that a take is not expected to occur, and
they are not discussed further beyond the explanation provided here.
These species regularly occur in the Chukchi Sea, but not as commonly
in the Beaufort Sea. Narwhals, Steller sea lions, and hooded seals are
considered extralimital to the proposed action area. These species
could occur in the Beaufort Sea, but are either uncommon or
extralimital east of Barrow (located in the Foggy Island Bay area and
surveys within the Bay have revealed zero sightings).
In addition, the polar bear may be found in Foggy Island Bay.
However, this species is managed by the U.S. Fish and Wildlife Service
and is not considered further in this document.
On October 11, 2016, NOAA released the Final Environmental Impact
Statement (FEIS) for the Effects of Oil and Gas Activities in the
Arctic Ocean (81 FR 72780, October 21, 2016) regarding geological and
geophysical (i.e., seismic) activities, ancillary activities, and
exploratory drilling. The Final EIS may be found at https://www.fisheries.noaa.gov/national/marine-mammal-protection/environmental-
impact-statement-eis-effects-oil-and-gas-activities. Although no
seismic activities are proposed by Hilcorp, the EIS contains detailed
information on marine mammal species proposed to be potentially taken
by Hilcorp's specified activities. More recently, BOEM released a final
EIS on the Liberty Project. We incorporate by reference the information
on the species authorized to be taken by Hilcorp's specified activities
from these documents and provide a summary and any relevant updates on
species status here.
Bowhead Whale
The only bowhead whale stock found within U.S. waters is the
Western Arctic stock, also known as the Bering-Chukchi-Beaufort stock
(Rugh et al., 2003) or Bering Sea stock (Burns et al., 1993). The
majority of the Western Arctic stock migrates annually from wintering
areas (December to March) in the northern Bering Sea, through the
Chukchi Sea in the spring (April through May), to the eastern Beaufort
Sea where they spend much of the summer (June through early to mid-
October), before returning again to the Bering Sea in the fall
(September through December) to overwinter
[[Page 70292]]
(Braham et al., 1980, Moore and Reeves 1993, Quakenbush et al., 2010a,
Citta et al., 2015). Some bowhead whales are found in the western
Beaufort, Chukchi, and Bering seas in summer, and these are thought to
be a part of the expanding Western Arctic stock (Rugh et al., 2003;
Clarke et al., 2013, 2014, 2015; Citta et al., 2015). The most recent
population parameters (e.g., abundance, PBR) of western Arctic bowhead
whales are provided in Table 2.
Bowhead whale distribution in the Beaufort Sea during summer-fall
has been studied by aerial surveys through the Bowhead Whale Aerial
Survey Project (BWASP). This project was funded or contracted by the
Minerals Management Service (MMS)/Bureau of Ocean Energy Management
(BOEM) and Bureau of Land Management (BLM) annually from 1979 to 2010.
The focus of the BWASP aerial surveys was the autumn migration of
bowhead whales through the Alaskan Beaufort Sea, although data were
collected on all marine mammals sighted. The NMFS National Marine
Mammal Laboratory (NMML) began coordinating BWASP in 2007, with funding
from MMS. In 2011, an Interagency Agreement between the BOEM and NMML
combined BWASP with COMIDA under the auspices of a single survey called
Aerial Surveys of Arctic Marine Mammals (ASAMM) (Clarke et al., 2012);
both studies are funded by BOEM. In September to mid-October, bowheads
begin their western migration out of the Canadian Beaufort Sea to the
Chukchi Sea (Figure 3.2-10). Most westward travel across the Beaufort
Sea by tagged whales was over the shelf, within 100 km (62 mi) of
shore, although a few whales traveled farther offshore (Quakenbush et
al., 2012).
During winter and spring, bowhead whales are closely associated
with sea ice (Moore and Reeves 1993, Quakenbush et al., 2010a, Citta et
al., 2015). The bowhead whale spring migration follows fractures in the
sea ice around the coast of Alaska, generally in the shear zone between
the shorefast ice and the mobile pack ice. During summer, most of the
population is in relatively ice-free waters in the southeastern
Beaufort Sea (Citta et al., 2015), an area often exposed to industrial
activity related to petroleum exploration (e.g., Richardson et al.,
1987, Davies, 1997). Summer aerial surveys conducted in the western
Beaufort Sea during July and August of 2012-2014 have had relatively
high sighting rates of bowhead whales, including cows with calves and
feeding animals (Clarke et al., 2013, 2014, 2015). During the autumn
migration through the Beaufort Sea, bowhead whales generally select
shelf waters (Citta et al., 2015). In winter in the Bering Sea, bowhead
whales often use areas with ~100 percent sea-ice cover, even when
polynyas are available (Quakenbush et al., 2010a, Citta et al., 2015).
From 2006 through 2014, median distance of bowhead whales from
shore was 23.6 km (14.7 mi) in the East Region and 24.2 km (15.0 mi) in
the West Region during previous low-ice years, with annual median
distances ranging from as close as 6.3 km (3.9 mi) in 2009 to 37.6 km
(23.4 mi) in 2013 (Clarke et al., 2015b). Median depth of sightings
during previous low-ice years was 39 m (128 ft) in the East Region and
21 m (69 ft) in the West Region; in 2014, median depth of on-transect
sightings was 20 m (66 ft) and 19 m (62 ft), respectively (Clarke et
al., 2015b). In September and October 2014, bowhead whales in the East
Region of the study area were sighted in shallower water and closer to
shore than in previous years of light sea ice cover; in the West
Region, bowhead sightings in fall 2014 were in shallower water than in
previous light ice years, but the distance from shore did not differ
(Clarke et al., 2015b). Behaviors included milling, swimming, and
feeding, to a lesser degree. The highest numbers of sightings were in
the central Beaufort Sea and east of Point Barrow. Overall, the most
shoreward edge of the bowhead migratory corridor for bowhead extends
approximately 40 km (25 mi) north from the barrier islands, which are
located approximately 7 km (4 mi) north of Liberty Project. The closest
approach of a tagged whale occurred in August 2016, when it came within
16 km of the proposed LDPI (Quakenbush, 2018).
Historically, there have been few spring, summer, or autumn
observations of bowheads in larger bays such as Camden, Prudhoe, and
Harrison Bays, although some groups or individuals have occasionally
been observed feeding around the periphery of or, less commonly, inside
the bays as migration demands and feeding opportunities permit.
Observations indicate that juvenile, sub-adult, and cow-calf pairs of
bowheads are the individuals most frequently observed in bays and
nearshore areas of the Beaufort, while more competitive whales are
found in the Canadian Beaufort and Barrow Canyon, as well as deeper
offshore waters (Clarke et al., 2011b, 2011c, 2011d, 2012, 2013, 2014,
2015b; Koski and Miller, 2009; Quakenbush et al., 2010).
Clarke et al. (2015) evaluated biologically important areas (BIAs)
for bowheads in the U.S. Arctic region and identified nine BIAs. The
spring (April-May) migratory corridor BIA for bowheads is far offshore
of the LDPI but within the transit portion of the action area, while
the fall (September-October) migratory corridor BIA (western Beaufort
on and north of the shelf) for bowheads is further inshore and closer
to the LDPI. Clarke et al. (2015) also identified four BIAs for
bowheads that are important for reproduction and encompassed areas
where the majority of bowhead whales identified as calves were observed
each season; none of these reproductive BIAs overlap with the LDPI, but
they may be encompassed in indirect areas such as vessel transit
routes. Finally, three bowhead feeding BIAs were identified. Again,
there is no spatial overlap of the activity area with these BIAs.
From July 8, 2008, through August 25, 2008, BPXA conducted a 3D
seismic survey in the Liberty Prospect, Beaufort Sea. During the August
survey, a mixed-species group of whales was observed in one sighting
near the barrier islands that included bowhead and gray whales (Aerts
et al., 2008). This is the only known survey sighting of bowhead whales
within Foggy Island Bay despite industry surveys occurring during the
open water season in 2010, 2014, and 2015, and NMFS aerial surveys
flown inside Foggy Island Bay in 2016 and 2017.
Alaska Natives have been taking bowhead whales for subsistence
purposes for at least 2,000 years (Marquette and Bockstoce, 1980,
Stoker and Krupnik, 1993). Subsistence takes have been regulated by a
quota system under the authority of the IWC since 1977. Alaska Native
subsistence hunters, primarily from 11 Alaska communities, take
approximately 0.1-0.5 percent of the population per annum (Philo et
al., 1993, Suydam et al., 2011). The average annual subsistence take
(by Natives of Alaska, Russia, and Canada) during the 5-year period
from 2011 through 2015 is 43 landed bowhead whales (Muto et al., 2018).
Gray Whale
The eastern North Pacific population of gray whales migrates along
the coasts of eastern Siberia, North America, and Mexico (Allen and
Angliss 2010; Weller et al., 2002), and its population size has been
steadily increasing, potentially reaching carrying capacity (Allen and
Angliss, 2010, 2012). Abundance estimates will likely rise and fall in
the future as the population finds a balance with the carrying-capacity
of the environment (Rugh et al., 2005). The steadily increasing
population abundance warranted delisting the
[[Page 70293]]
eastern North Pacific gray whale stock in 1994, as it was no longer
considered endangered or threatened under the ESA (Rugh et al., 1999).
A five-year status review determined that the stock was neither in
danger of extinction nor likely to become endangered in the foreseeable
future, thus, retaining the non-threatened classification (Rugh et al.,
1999). Table 2 provides population parameters for this stock.
The gray whale migration may be the longest of any mammalian
species. They migrate over 8,000 to 10,000 km (5,000 to 6,200 mi)
between breeding lagoons in Mexico and Arctic feeding areas each spring
and fall (Rugh et al., 1999). The southward migration out of the
Chukchi Sea generally begins during October and November, passing
through Unimak Pass in November and December, then continues along a
coastal route to Baja California (Rice et al., 1984). The northward
migration usually begins in mid-February and continues through May
(Rice et al. 1984).
Gray whales are the most coastal of all the large whales and
inhabit primarily inshore or shallow, offshore continental shelf waters
(Jones and Swartz, 2009); however, they are more common in the Chukchi
than in the Beaufort Sea. Throughout the summers of 2010 and 2011, gray
whales regularly occurred in small groups north of Point Barrow and
west of Barrow (George et al., 2011; Shelden et al., 2012). In 2011,
there were no sightings of gray whales east of Point Barrow during
ASAMM aerial surveys (Clarke et al., 2012); however, they were observed
east of Point Barrow, primarily in the vicinity of Barrow Canyon, from
August to October 2012 (Clarke et al., 2013). Gray whales were again
observed east of Point Barrow in 2013, with all sightings in August
except for one sighting in late October (Clarke et al., 2014). In 2014,
sightings in the Beaufort Sea included a few whales east of Point
Barrow and one north of Cross Island near Prudhoe Bay (Clarke et al.,
2015b). Gray whales prefer shoal areas (<60 m (197 ft) deep) with low
(<7 percent) ice cover (Moore and DeMaster, 1997). These areas provide
habitat rich in gray whale prey (amphipods, decapods, and other
invertebrates).
From July 8, 2008 through August 25, 2008, BPXA conducted a 3D
seismic survey in the Liberty Prospect, Beaufort Sea. During the August
survey, a mixed-species group of whales was observed in one sighting
near the barrier islands that included bowhead and gray whales (Aerts
et al., 2008). This is the only known survey sighting of gray whales
within Foggy Island Bay despite industry surveys occurring during the
open water season in 2010, 2014, and 2015, and NMFS aerial surveys
flown inside Foggy Island Bay in 2016 and 2017.
Beluga Whale
Five beluga whale stocks are present in Alaska, including the Cook
Inlet, Bristol Bay, eastern Bering Sea, eastern Chukchi Sea, and
Beaufort Sea stocks (O'Corry-Crowe et al., 1997, Allen and Angliss,
2015). The eastern Chukchi and Beaufort Sea stocks are thought to
overlap in the Beaufort Sea. Both stocks are closely associated with
open leads and polynyas in ice-covered regions throughout Arctic and
sub-Arctic waters of the Northern Hemisphere. Distribution varies
seasonally. Whales from both the Beaufort Sea and eastern Chukchi Sea
stocks overwinter in the Bering Sea. Belugas of the eastern Chukchi may
winter in offshore, although relatively shallow, waters of the western
Bering Sea (Richard et al., 2001), and the Beaufort Sea stock may
winter in more nearshore waters of the northern Bering Sea (R. Suydam,
pers. comm. 2012c). In the spring, belugas migrate to coastal
estuaries, bays, and rivers. Annual migrations may cover thousands of
kilometers (Allen and Angliss, 2010, 2012a).
Satellite telemetry data from 23 whales tagged in Kaseguluk Lagoon
in 1998 through 2002 provided information on movements and migrations
of eastern Chukchi Sea belugas. Animals initially traveled north and
east into the northern Chukchi and western Beaufort seas after capture
(Suydam et al., 2001, 2005). Movement patterns between July and
September vary by age and/or sex classes. Adult males frequent deeper
waters of the Beaufort Sea and Arctic Ocean (79-80[deg] N), where they
remain throughout the summer. Immature males moved farther north than
immature females but not as far north as adult males. All of the
belugas frequented water deeper than 200m (656 ft) along and beyond the
continental shelf break. Use of the inshore waters within the Beaufort
Sea Outer Continental Shelf lease sale area was rare (Suydam et al.,
2005).
Most information on the distribution and movements of belugas of
the Beaufort Sea stock was similarly derived using satellite tags. A
total of 30 belugas were tagged in the Mackenzie River Delta, Northwest
Territories, Canada, during summer and autumn in 1993, 1995, and 1997
(Richard et al., 2001). Approximately half of the tagged whales
traveled far offshore of the Alaskan coastal shelf, while the remainder
traveled on the shelf or near the continental slope (Richard et al.,
2001). Migration through Alaskan waters lasted an average of 15 days.
In 1997, all of the tagged belugas reached the western Chukchi Sea
(westward of 170[deg] W) between September 15 and October 9. Overall,
the main fall migration corridor for beluga whales is believed to be
approximately 62 mi (100 km) north of the Project Area (Richard et al.,
1997, 2001). Both the spring (April-May) and fall (September-October)
migratory corridor BIAs for belugas are far north of the proposed
action area because sightings of belugas from aerial surveys in the
western Beaufort Sea are primarily on the continental slope, with
relatively few sightings on the shelf (Clarke et al., 2015). No
reproductive and feeding BIAs exist for belugas in the action area
(Clarke et al., 2015).
O'Corry et al. (2018) studied genetic marker sets in 1,647 beluga
whales. The data set was from over 20 years and encompassed all of the
whales' major coastal summering regions in the Pacific Ocean. The
genetic marker analysis of the migrating whales revealed that while
both the wintering and summering areas of the eastern Chukchi Sea and
eastern Beaufort Sea subpopulations may overlap, the timing of spring
migration differs such that the whales hunted at coastal sites in
Chukotka, the Bering Strait (i.e., Diomede), and northwest Alaska
(i.e., Point Hope) in the spring and off of Alaska's Beaufort Sea coast
in summer were predominantly from the eastern Beaufort Sea population.
Earlier genetic investigations and recent telemetry studies show that
the spring migration of eastern Beaufort whales occurs earlier and
through denser sea ice than eastern Chukchi Sea belugas. The discovery
that a few individual whales found at some of these spring locations
had a higher likelihood of having eastern Chukchi Sea ancestry or being
of mixed-ancestry, indicates that the Bering Strait region is also an
area where the stock mix in spring. Citta et al. (2016) also observed
that tagged eastern Beaufort Sea whales migrated north in the spring
through the Bering Strait earlier than the eastern Chukchi belugas, so
they had to pass through the latter's primary wintering area.
Therefore, the eastern Chukchi stock should not be present in the
action area at any time in general, but especially during summer-late
fall, when the beluga exposures would be anticipated for this project.
Therefore, we assume all belugas impacted by the proposed project are
from the Beaufort Sea stock.
Beluga whales were regularly sighted during the September-October
BWASP and the more recent ASAMM aerial surveys of the Alaska Beaufort
Sea
[[Page 70294]]
coast. Burns and Seaman (1985) suggest that beluga whales are strongly
associated with the ice fringe and that the route of the autumn
migration may be mainly determined by the location of the drift ice
margin. Relatively few beluga whales have been observed in the
nearshore areas (on the continental shelf outside of the barrier
islands) of Prudhoe Bay. However, groups of belugas have been detected
nearshore in September (Clarke et al., 2011a) and opportunistic
sightings have been recorded from Northstar Island and Endicott. These
sightings are part of the fall migration which generally occurs farther
offshore, although a few sightings of a few individuals do occur closer
to the shore and occasionally inside the barrier islands of Foggy
Island Bay. During the 2008 seismic survey in Foggy Island Bay, three
sightings of eight individuals were observed at a location about 3 mi
(4.8 km) east of the Endicott Satellite Drilling Island (Aerts et al.,
2008). In 2014, during a BPXA 2D HR shallow geohazard survey in July
and August, PSOs recorded eight groups of approximately 19 individual
beluga whales, five of which were juveniles (Smultea et al., 2014).
During the open water season between July 9 and July 19, 2015, five
sightings of belugas occurred (Cate et al., 2015). Also in 2015,
acoustic monitoring was conducted in Foggy Island Bay between July 6
and September 22, 2015, to characterize ambient sound conditions and to
determine the acoustic occurrence of marine mammals near Hilcorp's
Liberty prospect in Foggy Island Bay (Frouin-Jouy et al., 2015). Two
recorders collected underwater sound data before, during, and after
Hilcorp's 2015 geohazard survey (July 6-Sept. 22). Detected marine
mammal vocalizations included those from beluga whales and pinnipeds.
Belugas were detected on five days by passive-recorders inside the bay
during the three-month survey period (Frouin-Jouy et al., 2015). During
the 2016 and 2017 ASAMM surveys flown inside Foggy Island Bay, no
belugas were observed. Beluga whales are the cetacean most likely to be
encountered during the open-water season in Foggy Island Bay, albeit
few in abundance.
Ringed Seal
One of five Arctic ringed seal stocks, the Alaska stock, occurs in
U.S. waters. The Arctic subspecies of ringed seals was listed as
threatened under the ESA on December 28, 2012, primarily due to
expected impacts on the population from declines in sea and snow cover
stemming from climate change within the foreseeable future (77 FR
76706). However, on March 11, 2016, the U.S. District Court for the
District of Alaska issued a decision in a lawsuit challenging the
listing of ringed seals under the ESA (Alaska Oil and Gas Association
et al. v. National Marine Fisheries Service, Case No. 4:14-cv-00029-
RRB). The decision vacated NMFS' listing of Arctic ringed seals as a
threatened species. However, On February 12, 2018, in Alaska Oil & Gas
Association v. Ross, Case No. 16-35380, the U.S. Court of Appeals for
the Ninth Circuit reversed the district court's 2016 decision. As such,
Arctic ringed seals remain listed as threatened under the ESA.
During winter and spring in the United States, ringed seals are
found throughout the Beaufort and Chukchi Seas; they occur in the
Bering Sea as far south as Bristol Bay in years of extensive ice
coverage. Most ringed seals that winter in the Bering and Chukchi Seas
are thought to migrate northward in spring with the receding ice edge
and spend summer in the pack ice of the northern Chukchi and Beaufort
Seas.
Ringed seals are resident in the Beaufort Sea year-round, and based
on results of previous surveys in Foggy Island Bay (Aerts et al., 2008,
Funk et al., 2008, Savarese et al., 2010, Smultea et al., 2014), and
monitoring from Northstar Island (Aerts and Richardson, 2009, 2010),
they are expected to be the most commonly occurring pinniped in the
action area year-round.
Ringed seals are present in the nearshore and sea ice year-round,
maintaining breathing holes and excavating subnivean lairs in the
landfast ice during the ice-covered season. Ringed seals overwinter in
the landfast ice in and around the LDPI action area. There is some
evidence indicating that ringed seal densities are low in water depths
of less than 3 m, where landfast ice extending from the shoreline
generally freezes to the sea bottom in very shallow waters during the
course of the winter (Moulton et al., 2002a, Moulton et al., 2002b,
Richardson and Williams, 2003). Ringed seals that breed on shorefast
ice may either forage within 100 km (62.1 mi) of their breeding habitat
or undertake extensive foraging trips to more productive areas at
distances of between 100-1,000 kilometers (Kelly et al., 2010b). Adult
Arctic ringed seals show site fidelity, returning to the same subnivean
site after the foraging period ends. Movements are limited during the
ice-bound months, including the breeding season, which limits their
foraging activities and may minimize gene flow within the species
(Kelly et al. 2010b). During April to early June (the reproductive
period), radio-tagged ringed seals inhabiting shorefast ice near
Prudhoe Bay had home range sizes generally less than 1,336 ac (500 ha)
in area (Kelly et al., 2005). Sub-adults, however, were not constrained
by the need to defend territories or maintain birthing lairs and
followed the advancing ice southward to winter along the Bering Sea ice
edge where there may be enhanced feeding opportunities and less
exposure to predation (Crawford et al., 2012). Sub-adult ringed seals
tagged in the Canadian Beaufort Sea similarly undertook lengthy
migrations across the continental shelf of the Alaskan Beaufort Sea
into the Chukchi Sea, passing Point Barrow prior to freeze-up in the
central Chukchi Sea (Harwood et al., 2012). Factors most influencing
seal densities during May through June in the central Beaufort Sea
between Oliktok Point and Kaktovik were water depth, distance to the
fast ice edge, and ice deformation. The highest densities of seals were
at depths of 5 to 35 m (16 to 144 ft) and on relatively flat ice near
the fast ice edge (Frost et al., 2004).
Sexual maturity in ringed seals varies with population status. It
can be as early as 3 years for both sexes and as late as 7 years for
males and 9 years for females. Ringed seals breed annually, with timing
varying regionally. Mating takes place while mature females are still
nursing their pups on the ice and is thought to occur under the ice
near birth lairs. In all subspecies except the Okhotsk, females give
birth to a single pup hidden from view within a snow-covered birth
lair. Ringed seals are unique in their use of these birth lairs. Pups
learn how to dive shortly after birth. Pups nurse for 5 to 9 weeks and,
when weaned, are four times their birth weights. Ringed seal pups are
more aquatic than other ice seal pups and spend roughly half their time
in the water during the nursing period (Lydersen and Hammill, 1993).
Pups are normally weaned before the break-up of spring ice.
Ringed seals are an important resource for Alaska Native
subsistence hunters. Approximately 64 Alaska Native communities in
western and northern Alaska, from Bristol Bay to the Beaufort Sea,
regularly harvest ice seals (Ice Seal Committee, 2016). Based on the
harvest data from 12 Alaska Native communities, a minimum estimate of
the average annual harvest of ringed seals in 2009-2013 is 1,050 seals
(Muto et al., 2016).
Other sources of mortality include commercial fisheries and
predation by
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marine and terrestrial predators including polar bears, arctic foxes,
walrus, and killer whales. During 2010-2014, incidental mortality and
serious injury of ringed seals was reported in 4 of the 22 federally-
regulated commercial fisheries in Alaska monitored for incidental
mortality and serious injury by fisheries observers: The Bering Sea/
Aleutian Islands flatfish trawl, Bering Sea/Aleutian Islands pollock
trawl, Bering Sea/Aleutian Islands Pacific cod trawl, and Bering Sea/
Aleutian Islands Pacific cod longline fisheries (Muto et al., 2016).
From May 1, 2011 to December 31, 2016, 657 seals, which included 233
dead stranded seals, 179 subsistence hunted seals, and 245 live seals,
were stranded or sampled during permitted health assessments studies.
The species involved were primarily ice seals including ringed,
bearded, ribbon, and spotted seals in northern and western Alaska. The
investigation identified that clinical signs were likely due to an
abnormality of the molt, but a definitive cause for the abnormal molt
was not determined.
Bearded Seal
Two subspecies of bearded seal have been described: E. b. barbatus
from the Laptev Sea, Barents Sea, North Atlantic Ocean, and Hudson Bay
(Rice 1998); and E. b. nauticus from the remaining portions of the
Arctic Ocean and the Bering and Okhotsk seas (Ognev, 1935, Scheffer,
1958, Manning, 1974, Heptner et al., 1976). On December 28, 2012, NMFS
listed two distinct population segments (DPSs) of the E. b. nauticus
subspecies of bearded seals--the Beringia DPS and Okhotsk DPS--as
threatened under the ESA (77 FR 76740). Similar to ringed seals, the
primary concern for these DPSs is the ongoing and projected loss of
sea-ice cover stemming from climate change, which is expected to pose a
significant threat to the persistence of these seals in the foreseeable
future (based on projections through the end of the 21st century;
Cameron et al., 2010). Similar to ringed seals, the ESA listing of the
Beringia and Okhotsk DPSs of bearded seal was challenged in the U.S.
District Court for the District of Alaska, and on July 25, 2014, the
court vacated NMFS' listing of those DPSs of bearded seals as
threatened under the ESA (Alaska Oil and Gas Association et al. v.
Pritzker, Case No. 4:13-cv-00018-RRB). However, the U.S. Court of
Appeals for the Ninth Circuit reversed the district court's 2016
decision on October 24, 2016 (Alaska Oil & Gas Association v. Pritzer,
Case No. 14-35806). As such, the Beringia and Okhotsk DPSs of bearded
seal remain listed as threatened under the ESA.
For the purposes of MMPA stock assessments, the Beringia DPS is
considered the Alaska stock of the bearded seal (Muto et al., 2016).
The Beringia DPS of the bearded seal includes all bearded seals from
breeding populations in the Arctic Ocean and adjacent seas in the
Pacific Ocean between 145[deg] E longitude (Novosibirskiye) in the East
Siberian Sea and 130[deg] W longitude in the Canadian Beaufort Sea,
except west of 157[deg] W longitude in the Bering Sea and west of the
Kamchatka Peninsula (where the Okhotsk DPS is found). They generally
prefer moving ice that produces natural openings and areas of open-
water (Heptner et al., 1976, Fedoseev, 1984, Nelson et al., 1984). They
usually avoid areas of continuous, thick, shorefast ice and are rarely
seen in the vicinity of unbroken, heavy, drifting ice or large areas of
multi-year ice (Fedoseev, 1965, Burns and Harbo, 1972, Burns and Frost,
1979, Burns, 1981, Smith, 1981, Fedoseev, 1984, Nelson et al., 1984).
Spring surveys conducted in 1999-2000 along the Alaska coast
indicate that bearded seals are typically more abundant 20-100 nautical
miles (nmi) from shore than within 20 nmi from shore, except for high
concentrations nearshore to the south of Kivalina (Bengtson et al.,
2005; Simpkins et al., 2003).
Although bearded seal vocalizations (produced by adult males) have
been recorded nearly year-round in the Beaufort Sea (MacIntyre et al.,
2013, MacIntyre et al., 2015), most bearded seals overwinter in the
Bering Sea. In addition, during late winter and early spring, Foggy
Island Bay is covered with shorefast ice and the nearest lead systems
are at least several kilometers away, making the area unsuitable
habitat for bearded seals. Therefore, bearded seals are not expected to
be encountered in or near the LDPI portion of the action area during
this time (from late winter through early spring).
During the open-water period, the Beaufort Sea likely supports
fewer bearded seals than the Chukchi Sea because of the more extensive
foraging habitat available to bearded seals in the Chukchi Sea. In
addition, as a result of shallow waters, the sea floor in Foggy Island
Bay south of the barrier islands is often scoured by ice, which limits
the presence of bearded seal prey species. Nevertheless, aerial and
vessel-based surveys associated with seismic programs, barging, and
government surveys in this area between 2005 and 2010 reported several
bearded seal sightings (Green and Negri. 2005, Green and Negri, 2006,
Green et al., 2007, Funk et al., 2008, Hauser et al., 2008, Savarese et
al., 2010, Clarke et al., 2011, Reiser et al., 2011). In addition,
eight bearded seal sightings were documented during shallow geohazard
seismic and seabed mapping surveys conducted in July and August 2014
(Smultea et al., 2014). Frouin-Mouy et al. (2016) conducted acoustic
monitoring in Foggy Island Bay from early July to late September 2014,
and detected pinniped vocalizations on 10 days via the nearshore
recorder and on 66 days via the recorder farther offshore. Although the
majority of these detections were unidentified pinnipeds, bearded seal
vocalizations were positively identified on two days (Frouin-Mouy et
al., 2016).
Bearded seals are an important resource for Alaska Native
subsistence hunters. Approximately 64 Alaska Native communities in
western and northern Alaska, from Bristol Bay to the Beaufort Sea,
regularly harvest ice seals (Ice Seal Committee, 2016). However, during
2009-2013, only 12 of 64 coastal communities were surveyed for bearded
seals; and, of those communities, only 6 were surveyed for two or more
consecutive years (Ice Seal Committee, 2016). Based on the harvest data
from these 12 communities (Table 2), a minimum estimate of the average
annual harvest of bearded seals in 2009-2013 is 390 seals. Harvest
surveys are designed to estimate harvest within the surveyed community,
but because of differences in seal availability, cultural hunting
practices, and environmental conditions, extrapolating harvest numbers
beyond that community is not appropriate (Muto et al., 2016).
Of the 22 federally-regulated U.S. commercial fisheries in Alaska
monitored for incidental mortality and serious injury by fisheries
observers, 12 fisheries could potentially interact with bearded seals.
During 2010-2014, incidental mortality and serious injury of bearded
seals occurred in three fisheries: The Bering Sea/Aleutian Islands
pollock trawl, Bering Sea/Aleutian Islands flatfish trawl, and Bering
Sea/Aleutian Islands Pacific cod trawl fisheries (Muto et al., 2016).
This species was also part of the aforementioned 2011-2016 UME.
Spotted Seal
Spotted seals are distributed along the continental shelf of the
Bering, Chukchi, and Beaufort seas, and the Sea of Okhotsk south to the
western Sea of Japan and northern Yellow Sea. Eight main areas of
spotted seal breeding have been reported (Shaughnessy and Fay, 1977)
and Boveng et al. (2009) grouped those breeding areas into three DPSs:
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The Bering DPS, which includes breeding areas in the Bering Sea and
portions of the East Siberian, Chukchi, and Beaufort seas that may be
occupied outside the breeding period; the Okhotsk DPS; and the Southern
DPS, which includes spotted seals breeding in the Yellow Sea and Peter
the Great Bay in the Sea of Japan. For the purposes of MMPA stock
assessments, NMFS defines the Alaska stock of spotted seals to be that
portion of the Bering DPS in U.S. waters.
The distribution of spotted seals is seasonally related to specific
life-history events that can be broadly divided into two periods: Late-
fall through spring, when whelping, nursing, breeding, and molting
occur in association with the presence of sea ice on which the seals
haul out, and summer through fall when seasonal sea ice has melted and
most spotted seals use land for hauling out (Boveng et al., 2009).
Spotted seals are most numerous in the Bering and Chukchi seas
(Quakenbush, 1988), although small numbers do range into the Beaufort
Sea during summer (Rugh et al., 1997; Lowry et al., 1998).
At Northstar, few spotted seals have been observed. A total of 12
spotted seals were positively identified near the source-vessel during
open-water seismic programs in the central Alaskan Beaufort Sea,
generally occurring near Northstar from 1996 to 2001 (Moulton and
Lawson, 2002). The number of spotted seals observed per year ranged
from zero (in 1998 and 2000) to four (in 1999).
During a seismic survey in Foggy Island Bay, PSOs recorded 18
pinniped sightings, of which one was confirmed as a spotted seal (Aerts
et al., 2008). Spotted seals were the second most abundant seal species
observed by PSOs during Hilcorp's geohazard surveys in July-August 2014
(Smultea et al., 2014) and in July 2015 (Cate et al., 2015). Given
their seasonal distribution and low numbers in the nearshore waters of
the central Alaskan Beaufort Sea, no spotted seals are expected in the
action area during late winter and spring, but they could be present in
low numbers during the summer or fall.
Similar to other ice seal species, spotted seals are an important
resource for Alaska Native subsistence hunters. Of the 12 communities
(out of 64) surveyed during 2010-2014, the minimum annual spotted seal
harvest estimates totaled across 12 out of 64 user communities surveyed
ranged from 83 (in 2 communities) to 518 spotted seals (in 10
communities). Based on the harvest data from these 12 communities, a
minimum estimate of the average annual harvest of spotted seals in
2010-2014 is 328 seals.
From 2011-2015, incidental mortality and serious injury of spotted
seals occurred in 2 of the 22 federally-regulated U.S. commercial
fisheries in Alaska monitored for incidental mortality and serious
injury by fisheries observers: The Bering Sea/Aleutian Islands flatfish
trawl and Bering Sea/Aleutian Islands Pacific cod longline fisheries.
In 2014, there was one report of a mortality incidental to research on
the Alaska stock of spotted seals, resulting in a mean annual mortality
and serious injury rate of 0.2 spotted seals from this stock in 2011-
2015. This species was also part of the aforementioned 2011-2016 UME.
Marine Mammal Hearing
Hearing is the most important sensory modality for marine mammals
underwater, and exposure to anthropogenic sound can have deleterious
effects. To appropriately assess the potential effects of exposure to
sound, it is necessary to understand the frequency ranges marine
mammals are able to hear. Current data indicate that not all marine
mammal species have equal hearing capabilities (e.g., Richardson et
al., 1995; Wartzok and Ketten, 1999; Au and Hastings, 2008). To reflect
this, Southall et al. (2007 and 2019) recommended that marine mammals
be divided into functional hearing groups based on directly measured or
estimated hearing ranges on the basis of available behavioral response
data, audiograms derived using auditory evoked potential techniques,
anatomical modeling, and other data. Note that no direct measurements
of hearing ability have been successfully completed for mysticetes
(i.e., low-frequency cetaceans). Subsequently, NMFS (2016) described
generalized hearing ranges for these marine mammal hearing groups.
Generalized hearing ranges were chosen based on the approximately 65 dB
threshold from the normalized composite audiograms, with an exception
for lower limits for low-frequency cetaceans where the result was
deemed to be biologically implausible and the lower bound from Southall
et al. (2007) retained. The functional groups and the associated
frequencies are indicated below (note that these frequency ranges
correspond to the range for the composite group, with the entire range
not necessarily reflecting the capabilities of every species within
that group):
Low-frequency cetaceans (mysticetes): Generalized hearing
is estimated to occur between approximately 7 (hertz) Hz and 35 kHz;
Mid-frequency cetaceans (larger toothed whales, beaked
whales, and most delphinids): Generalized hearing is estimated to occur
between approximately 150 Hz and 160 kHz;
High-frequency cetaceans (porpoises, river dolphins, and
members of the genera Kogia and Cephalorhynchus; including two members
of the genus Lagenorhynchus, on the basis of recent echolocation data
and genetic data): Generalized hearing is estimated to occur between
approximately 275 Hz and 160 kHz;
Pinnipeds in water; Phocidae (true seals): functional
hearing is estimated to occur between approximately 50 Hz to 86 kHz;
and
Pinnipeds in water; Otariidae (eared seals): functional
hearing is estimated to occur between approximately 60 Hz and 39 kHz.
For more detail concerning these groups and associated frequency
ranges, please see NMFS (2018) for a review of available information.
Six marine mammal species (three cetacean and three phocid pinniped)
have the potential to co-occur with Hilcorp's LDPI project. Of the
three cetacean species that may be present, two are classified as low-
frequency cetaceans (i.e., all mysticete species) and one is classified
as a mid-frequency cetacean (beluga whale).
Potential Effects of the Specified Activity on Marine Mammals and Their
Habitat
This section includes a summary and discussion of the ways that
components of the specified activity may impact marine mammals and
their habitat. The Estimated Take by Incidental Harassment section
later in this document includes a quantitative analysis of the number
of individuals that are expected to be taken by this activity. The
Negligible Impact Analysis and Determination section considers the
content of this section, the Estimated Take by Incidental Harassment
section, and the Mitigation section, to draw conclusions regarding the
likely impacts of these activities on the reproductive success or
survivorship of individuals and how those impacts on individuals are
likely to impact marine mammal species or stocks.
The potential impacts of the LDPI on marine mammals involve both
non-acoustic and acoustic effects. Potential non-acoustic effects could
result from the physical presence of personnel, structures and
equipment, construction or maintenance activities, and the occurrence
of oil spills. The LDPI
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project also has the potential to result in mortality and serious
injury of ringed seals via direct physical interaction on ice roads and
harass (by Level A harassment and Level B harassment) cetaceans and
seals via acoustic disturbance. We first discuss the effects of ice
road and ice trail construction and maintenance on ringed seals with
respect to direct human interaction followed by an in-depth discussion
on sound and potential effects on marine mammals from acoustic
disturbance. The potential for and potential impacts from both small
and large oil spills are discussed in more detail later in this
section; however, please note Hilcorp did not request, nor is NMFS
proposing to authorize, takes from oil spills.
Mortality, Serious Injury and Non-Acoustic Harassment--Ice Seals
This section discusses the potential impacts of ice road
construction, use, and maintenance on ringed seals, the only species
likely to be encountered during this activity. Acoustic impacts from
this and other activities (e.g., pile driving) are provided later in
the document. To assess the potential impacts from ice roads, one must
understand sea ice dynamics, the influence of ice roads on sea ice, and
ice seal ecology.
Sea ice is constantly moving and flexing due to winds, currents,
and snow load. Sea ice grows (thickens) to its maximum in March, then
begins to degrade once solar heating increases above the necessary
threshold. Sea ice will thin and crack due to atmospheric pressure and
temperature changes. In the absence of ice roads, sea ice is constantly
cracking, deforming (creating pressure ridges and hummocks), and
thickening or thinning. Ice road construction interrupts this dynamic
by permanently thickening and stabilizing the sea ice for the season;
however, it thins and weakens sea ice adjacent to ice roads due to the
weight of the ice road and use as the speed and load of vehicles using
the road creates pressure waves in the ice, cracking natural ice
adjacent to the road (pers. comm., M. Williams, August 17, 2018). These
cracks and thinned ice, occurring either naturally or adjacent to ice
roads, are easily exploitable habitat for ringed seals.
As discussed in the Description of Marine Mammals section, ringed
seals build lairs which are typically concentrated along pressure
ridges, cracks, leads, or other surface deformations (Smith and
Stirling 1975, Hammill and Smith, 1989, Furgal et al., 1996). To build
a lair, a pregnant female will first excavate a breathing hole, most
easily in cracked or thin ice. The lair will then be excavated (snow
must be present for lair construction). Later in the season, basking
holes may be created from collapsed lairs or new basking holes will be
excavated; both of which must have breathing holes and surface access
(pers. comm., M. Williams, August 17, 2018).
Williams et al. (2006) provides the most in-depth discussion of
ringed seal use around Northstar Island, the first offshore oil and gas
production facility seaward of the barrier islands in the Alaskan
Beaufort Sea. Northstar is located 9.5 km from the mainland on a
manmade gravel island in 12 m of water. In late 2000 and early 2001,
sea ice in areas near Northstar Island where summer water depth was
greater than 1.5 m were searched for ringed seal structures. At
Northstar, ringed seals were documented creating and using sea ice
structures (basking holes, breathing holes, or birthing lairs) within
11 to 3,500 m (36 to 11,482 ft) of Northstar infrastructure which
includes ice roads, pipeline, and the island itself (Williams et al.,
2006). Birth lairs closest to Northstar infrastructure were 882 m and
144 m (2,894 and 374 ft) from the island and ice road, respectively
(Williams et al., 2006). Two basking holes were found within 11 and 15
m (36 and 49 ft) from the nominal centerline of a Northstar ice road
and were still in use by the end of the study (Williams et al., 2006).
Although located in deeper water outside of the barrier islands, we
anticipate ringed seals would use ice around the LDPI and associated
ice roads in a similar manner.
Since 1998, there have been three documented incidents of ringed
seal interactions on North Slope ice roads, with one recorded
mortality. On April 17, 1998, during a vibroseis on-ice seismic
operation outside of the barrier islands east of Bullen Point in the
eastern Beaufort Sea, a ringed seal pup was killed when its lair was
destroyed by a Caterpillar tractor clearing an ice road. The lair was
located on ice over water 9 m (29 ft) deep with an ice thickness of 1.3
m (4.3 ft). It was reported that an adult may have been present in the
lair when it was destroyed. Crew found blood on the ice near an open
hole approximately 1.3 km (0.8 mi) from the destroyed lair; this could
have been from a wounded adult (MacLean, 1998). On April 24, 2018, a
Tucker (a tracked vehicle used in snow conditions) traveling on a
Northstar sea ice trail broke through a brine pocket. After moving the
Tucker, a seal pup climbed out of the hole in the ice, but no adult was
seen in the area. The seal pup remained in the area for the next day
and a half. This seal was seen in an area with an estimated water depth
of 6 to 7 m (20 to 24 ft) (Hilcorp, 2018b). The third reported incident
occurred on April 28, 2018, when a contractor performing routine
maintenance activities to relocate metal plates beneath the surface of
the ice road from Oliktok Point to Spy Island Drill site spotted a
ringed seal pup next to what may have been a lair site. No adult was
observed in the area. The pup appeared to be acting normally and was
seen going in and out of the opening several times (Eni, 2018).
Overall, NMFS does not anticipate the potential for mortality or
serious injury of ringed seals to be high given there has been only one
documented mortality over 25 years of ice road construction in the
Arctic. However, the potential does exist; therefore, we are including
a small amount of mortality or serious injury (n = 2) in this rule over
the five-year life of the regulations. To mitigate this risk, NMFS and
Hilcorp have developed a number of BMPs aimed at reducing the potential
of disturbing (e.g., crushing) ice seal structures on ice roads (see
Mitigation and Monitoring sections).
Potential Acoustic Impacts--Level A Harassment and Level B Harassment
In the following discussion, we provide general background
information on sound before considering potential effects to marine
mammals from sound produced by construction and operation of the LDPI.
Description of Sound Sources
This section contains a brief technical background on sound, on the
characteristics of certain sound types, and on metrics used in this
proposal inasmuch as the information is relevant to the specified
activity and to a discussion of the potential effects of the specified
activity on marine mammals found later in this document. For general
information on sound and its interaction with the marine environment,
please see, e.g., Au and Hastings (2008); Richardson et al. (1995);
Urick (1983).
Sound travels in waves, the basic components of which are
frequency, wavelength, velocity, and amplitude. Frequency is the number
of pressure waves that pass by a reference point per unit of time and
is measured in Hz or cycles per second. Wavelength is the distance
between two peaks or corresponding points of a sound wave (length of
one cycle). Higher frequency sounds have shorter wavelengths than lower
frequency sounds, and typically attenuate (decrease) more rapidly,
except in certain cases in shallower
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water. Amplitude is the height of the sound pressure wave or the
``loudness'' of a sound and is typically described using the relative
unit of the decibel (dB). A sound pressure level (SPL) in dB is
described as the ratio between a measured pressure and a reference
pressure (for underwater sound, this is 1 microPascal ([mu]Pa)), and is
a logarithmic unit that accounts for large variations in amplitude;
therefore, a relatively small change in dB corresponds to large changes
in sound pressure. The source level (SL) represents the SPL referenced
at a distance of 1 m from the source (referenced to 1 [mu]Pa), while
the received level is the SPL at the listener's position (referenced to
1 [mu]Pa).
Root mean square (rms) is the quadratic mean sound pressure over
the duration of an impulse. Root mean square is calculated by squaring
all of the sound amplitudes, averaging the squares, and then taking the
square root of the average (Urick, 1983). Root mean square accounts for
both positive and negative values; squaring the pressures makes all
values positive so that they may be accounted for in the summation of
pressure levels (Hastings and Popper, 2005). This measurement is often
used in the context of discussing behavioral effects, in part because
behavioral effects, which often result from auditory cues, may be
better expressed through averaged units than by peak pressures.
Sound exposure level (SEL; represented as dB re 1 [mu]Pa\2\-s)
represents the total energy in a stated frequency band over a stated
time interval or event, and considers both intensity and duration of
exposure. The per-pulse SEL is calculated over the time window
containing the entire pulse (i.e., 100 percent of the acoustic energy).
SEL is a cumulative metric; it can be accumulated over a single pulse
or calculated over periods containing multiple pulses. Cumulative SEL
represents the total energy accumulated by a receiver over a defined
time window or during an event. Peak sound pressure (also referred to
as zero-to-peak sound pressure or 0-pk) 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.
When underwater objects vibrate or activity occurs, sound-pressure
waves are created. These waves alternately compress and decompress the
water as the sound wave travels. Underwater sound waves radiate in a
manner similar to ripples on the surface of a pond and may be either
directed in a beam or beams or may radiate in all directions
(omnidirectional sources), as is the case for sound produced by the
pile driving activity considered here. The compressions and
decompressions associated with sound waves are detected as changes in
pressure by aquatic life and man-made sound receptors such as
hydrophones.
Even in the absence of sound from the specified activity, the
underwater environment is typically loud due to ambient sound, which is
defined as environmental background sound levels lacking a single
source or point (Richardson et al., 1995). The sound level of a region
is defined by the total acoustical energy being generated by known and
unknown sources. These sources may include physical (e.g., wind and
waves, earthquakes, ice, atmospheric sound), biological (e.g., sounds
produced by marine mammals, fish, and invertebrates), and anthropogenic
(e.g., vessels, dredging, construction) sound. A number of sources
contribute to ambient sound, including wind and waves, which are a main
source of naturally occurring ambient sound for frequencies between 200
Hz and 50 kHz (Mitson, 1995). In general, ambient sound levels tend to
increase with increasing wind speed and wave height. Precipitation can
become an important component of total sound at frequencies above 500
Hz, and possibly down to 100 Hz during quiet times. Marine mammals can
contribute significantly to ambient sound levels, as can some fish and
snapping shrimp. The frequency band for biological contributions is
from approximately 12 Hz to over 100 kHz. Sources of ambient sound
related to human activity include transportation (surface vessels),
dredging and construction, oil and gas drilling and production,
geophysical surveys, sonar, and explosions. Vessel noise typically
dominates the total ambient sound for frequencies between 20 and 300
Hz. In general, the frequencies of anthropogenic sounds are below 1 kHz
and, if higher frequency sound levels are created, they attenuate
rapidly.
The sum of the various natural and anthropogenic sound sources that
comprise ambient sound at any given location and time depends not only
on the source levels (as determined by current weather conditions and
levels of biological and human activity) but also on the ability of
sound to propagate through the environment. In turn, sound propagation
is dependent on the spatially and temporally varying properties of the
water column and sea floor, and is frequency-dependent. As a result of
the dependence on a large number of varying factors, ambient sound
levels can be expected to vary widely over both coarse and fine spatial
and temporal scales. Sound levels at a given frequency and location can
vary by 10-20 decibels (dB) from day to day (Richardson et al., 1995).
The result is that, depending on the source type and its intensity,
sound from the specified activity may be a negligible addition to the
local environment or could form a distinctive signal that may affect
marine mammals.
Sounds are often considered to fall into one of two general types:
Pulsed and non-pulsed (defined in the following). The distinction
between these two sound types is important because they have differing
potential to cause physical effects, particularly with regard to
hearing (e.g., Ward, 1997 in Southall et al., 2007). See Southall et
al. (2007) for an in-depth discussion of these concepts. The
distinction between these two sound types is not always obvious, as
certain signals share properties of both pulsed and non-pulsed sounds.
A signal near a source could be categorized as a pulse, but due to
propagation effects as it moves farther from the source, the signal
duration becomes longer (e.g., Greene and Richardson, 1988).
Pulsed sound sources (e.g., airguns, explosions, gunshots, sonic
booms, impact pile driving) produce signals that are brief (typically
considered to be less than one second), broadband, atonal transients
(ANSI, 1986, 2005; Harris, 1998; NIOSH, 1998; ISO, 2003) and occur
either as isolated events or repeated in some succession. Pulsed sounds
are all characterized by a relatively rapid rise from ambient pressure
to a maximal pressure value followed by a rapid decay period that may
include a period of diminishing, oscillating maximal and minimal
pressures, and generally have an increased capacity to induce physical
injury as compared with sounds that lack these features.
Non-pulsed sounds can be tonal, narrowband, or broadband, brief or
prolonged, and may be either continuous or intermittent (ANSI, 1995;
NIOSH, 1998). Some of these non-pulsed sounds can be transient signals
of short duration but without the essential properties of pulses (e.g.,
rapid rise time). Examples of non-pulsed sounds include those produced
by vessels, aircraft, machinery operations such as drilling or
dredging, vibratory pile driving, and active sonar systems. The
duration of such sounds, as received at a distance, can be greatly
extended in a highly reverberant environment.
[[Page 70299]]
The impulsive sound generated by impact hammers is characterized by
rapid rise times and high peak levels. Vibratory hammers produce non-
impulsive, continuous noise at levels significantly lower than those
produced by impact hammers. Rise time is slower, reducing the
probability and severity of injury, and sound energy is distributed
over a greater amount of time (e.g., Nedwell and Edwards, 2002; Carlson
et al., 2005).
Acoustic Effects
We previously provided general background information on marine
mammal hearing (see ``Description of Marine Mammals in the Area of the
Specified Activity''). Here, we discuss the potential effects of sound
on marine mammals.
Potential Effects of Underwater Sound--Note that, in the following
discussion, we refer in many cases to a review article concerning
studies of noise-induced hearing loss conducted from 1996-2015 (i.e.,
Finneran, 2015). For study-specific citations, please see that work.
Anthropogenic sounds cover a broad range of frequencies and sound
levels and can have a range of highly variable impacts on marine life,
from none or minor to potentially severe responses, depending on
received levels, duration of exposure, behavioral context, and various
other factors. The potential effects of underwater sound from active
acoustic sources can potentially result in one or more of the
following: temporary or permanent hearing impairment, non-auditory
physical or physiological effects, behavioral disturbance, stress, and
masking (Richardson et al., 1995; Gordon et al., 2004; Nowacek et al.,
2007; Southall et al., 2007; G[ouml]tz et al., 2009). The degree of
effect is intrinsically related to the signal characteristics, received
level, distance from the source, and duration of the sound exposure. In
general, sudden, high level sounds can cause hearing loss, as can
longer exposures to lower level sounds. Temporary or permanent loss of
hearing will occur almost exclusively for noise within an animal's
hearing range. We first describe specific manifestations of acoustic
effects before providing discussion specific to pile driving.
Richardson et al. (1995) described zones of increasing intensity of
effect that might be expected to occur, in relation to distance from a
source and assuming that the signal is within an animal's hearing
range. First is the area within which the acoustic signal would be
audible (potentially perceived) to the animal but not strong enough to
elicit any overt behavioral or physiological response. The next zone
corresponds with the area where the signal is audible to the animal and
of sufficient intensity to elicit behavioral or physiological
responsiveness. Third is a zone within which, for signals of high
intensity, the received level is sufficient to potentially cause
discomfort or tissue damage to auditory or other systems. Overlaying
these zones to a certain extent is the area within which masking (i.e.,
when a sound interferes with or masks the ability of an animal to
detect a signal of interest that is above the absolute hearing
threshold) may occur; the masking zone may be highly variable in size.
Potential effects from impulsive sound sources can range in
severity from effects such as behavioral disturbance or tactile
perception to physical discomfort, slight injury of the internal organs
and the auditory system, or mortality (Yelverton et al., 1973). Non-
auditory physiological effects or injuries that theoretically might
occur in marine mammals exposed to high level underwater sound or as a
secondary effect of extreme behavioral reactions (e.g., change in dive
profile as a result of an avoidance reaction) caused by exposure to
sound include neurological effects, bubble formation, resonance
effects, and other types of organ or tissue damage (Cox et al., 2006;
Southall et al., 2007; Zimmer and Tyack, 2007; Tal et al., 2015). The
construction and operational activities associated with the LDPI do not
involve the use of devices such as explosives or mid-frequency tactical
sonar that are associated with these types of effects.
Auditory Threshold Shifts
NMFS defines threshold shift (TS) as a change, usually an increase,
in the threshold of audibility at a specified frequency or portion of
an individual's hearing range above a previously established reference
level (NMFS, 2018). The amount of threshold shift is customarily
expressed in decibels (ANSI, 1995). Threshold shift can be permanent
(PTS) or temporary (TTS). As described in NMFS (2018), there are
numerous factors to consider when examining the consequence of TS,
including, but not limited to, the signal temporal pattern (e.g.,
impulsive or non-impulsive), likelihood an individual would be exposed
for a long enough duration or to a high enough level to induce a TS,
the magnitude of the TS, time to recovery (seconds to minutes or hours
to days), the frequency range of the exposure (i.e., spectral content),
the hearing and vocalization frequency range of the exposed species
relative to the signal's frequency spectrum (i.e., how animal uses
sound within the frequency band of the signal; e.g., Kastelein et al.,
2014b), and their overlap (e.g., spatial, temporal, and spectral).
Marine mammals exposed to high-intensity sound, or to lower-
intensity sound for prolonged periods, can experience hearing threshold
shift (TS), which is the loss of hearing sensitivity at certain
frequency ranges (Finneran, 2015). TS can be permanent (PTS), in which
case the loss of hearing sensitivity is not fully recoverable, or
temporary (TTS), in which case the animal's hearing threshold would
recover over time (Southall et al., 2007). Repeated sound exposure that
leads to TTS could cause PTS. In severe cases of PTS, there can be
total or partial deafness, while in most cases the animal has an
impaired ability to hear sounds in specific frequency ranges (Kryter,
1985).
When PTS occurs, there is physical damage to the sound receptors in
the ear (i.e., tissue damage), whereas TTS represents primarily tissue
fatigue and is reversible (Southall et al., 2007). In addition, other
investigators have suggested that TTS is within the normal bounds of
physiological variability and tolerance and does not represent physical
injury (e.g., Ward, 1997). Therefore, NMFS does not consider TTS to
constitute auditory injury.
Relationships between TTS and PTS thresholds have not been studied
in marine mammals, and there is no PTS data for cetaceans, but such
relationships are assumed to be similar to those in humans and other
terrestrial mammals. PTS typically occurs at exposure levels at least
several decibels above (a 40-dB threshold shift approximates PTS onset;
e.g., Kryter et al., 1966; Miller, 1974) that inducing mild TTS (a 6-dB
threshold shift approximates TTS onset; e.g., Southall et al. 2007).
Based on data from terrestrial mammals, a precautionary assumption is
that the PTS thresholds for impulse sounds (such as impact pile driving
pulses as received close to the source) are at least 6 dB higher than
the TTS threshold on a peak-pressure basis and PTS cumulative sound
exposure level thresholds are 15 to 20 dB higher than TTS cumulative
sound exposure level thresholds (Southall et al., 2007). Given the
higher level of sound or longer exposure duration necessary to cause
PTS as compared with TTS, it is considerably less likely that PTS could
occur.
TTS is the mildest form of hearing impairment that can occur during
exposure to sound (Kryter, 1985). While
[[Page 70300]]
experiencing TTS, the hearing threshold rises, and a sound must be at a
higher level in order to be heard. In terrestrial and marine mammals,
TTS can last from minutes or hours to days (in cases of strong TTS). In
many cases, hearing sensitivity recovers rapidly after exposure to the
sound ends. Few data on sound levels and durations necessary to elicit
mild TTS have been obtained for marine mammals.
Marine mammal hearing plays a critical role in communication with
conspecifics, and interpretation of environmental cues for purposes
such as predator avoidance and prey capture. Depending on the degree
(elevation of threshold in dB), duration (i.e., recovery time), and
frequency range of TTS, and the context in which it is experienced, TTS
can have effects on marine mammals ranging from discountable to
serious. For example, a marine mammal may be able to readily compensate
for a brief, relatively small amount of TTS in a non-critical frequency
range that occurs during a time where ambient noise is lower and there
are not as many competing sounds present. Alternatively, a larger
amount and longer duration of TTS sustained during times when
communication is critical for successful mother/calf interactions could
have more serious impacts.
Currently, TTS data only exist for four species of cetaceans
(bottlenose dolphin (Tursiops truncatus), beluga whale (Delphinapterus
leucas), harbor porpoise, and Yangtze finless porpoise (Neophocoena
asiaeorientalis)) and three species of pinnipeds (northern elephant
seal, harbor seal, and California sea lion) exposed to a limited number
of sound sources (i.e., mostly tones and octave-band noise) in
laboratory settings (Finneran, 2015). TTS was not observed in trained
spotted (Phoca largha) and ringed (Pusa hispida) seals exposed to
impulsive noise at levels matching previous predictions of TTS onset
(Reichmuth et al., 2016). In general, harbor seals and harbor porpoises
have a lower TTS onset than other measured pinniped or cetacean species
(Finneran, 2015). Additionally, the existing marine mammal TTS data
come from a limited number of individuals within these species. There
are no data available on noise-induced hearing loss for mysticetes. For
summaries of data on TTS in marine mammals or for further discussion of
TTS onset thresholds, please see Southall et al. (2007), Finneran and
Jenkins (2012), Finneran (2015), and NMFS (2018).
NMFS defines TTS as ``a temporary, reversible increase in the
threshold of audibility at a specified frequency or portion of an
individual's hearing range above a previously established reference
level'' (NMFS, 2016). A TTS of 6 dB is considered the minimum threshold
shift clearly larger than any day-to-day or session-to-session
variation in a subject's normal hearing ability (Schlundt et al., 2000;
Finneran et al., 2000; Finneran et al., 2002, as reviewed in Southall
et al., 2007 for a review). TTS can last from minutes or hours to days
(i.e., there is recovery), occur in specific frequency ranges (i.e., an
animal might only have a temporary loss of hearing sensitivity between
the frequencies of 1 and 10 kHz)), and can be of varying amounts (for
example, an animal's hearing sensitivity might be temporarily reduced
by only 6 dB or reduced by 30 dB). Currently, TTS measurements exist
for only four species of cetaceans (bottlenose dolphins, belugas,
harbor porpoises, and Yangtze finless porpoise) and three species of
pinnipeds (Northern elephant seal, harbor seal, and California sea
lion). These TTS measurements are from a limited number of individuals
within these species.
Depending on the degree (elevation of threshold in dB), duration
(i.e., recovery time), and frequency range of TTS, and the context in
which it is experienced, TTS can have effects on marine mammals ranging
from discountable to serious (similar to those discussed in auditory
masking, below). For example, a marine mammal may be able to readily
compensate for a brief, relatively small amount of TTS in a non-
critical frequency range that takes place during a time when the animal
is traveling through the open ocean, where ambient noise is lower and
there are not as many competing sounds present. Alternatively, a larger
amount and longer duration of TTS sustained during time when
communication is critical for successful mother/calf interactions could
have more serious impacts. We note that reduced hearing sensitivity as
a simple function of aging has been observed in marine mammals, as well
as humans and other taxa (Southall et al., 2007), so we can infer that
strategies exist for coping with this condition to some degree, though
likely not without cost.
Behavioral Effects--Behavioral disturbance from elevated noise
exposure may include a variety of effects, including subtle changes in
behavior (e.g., minor or brief avoidance of an area or changes in
vocalizations), more conspicuous changes in similar behavioral
activities, and more sustained and/or potentially severe reactions,
such as displacement from or abandonment of high-quality habitat.
Behavioral responses to sound are highly variable and context-specific
and any reactions depend on numerous intrinsic and extrinsic factors
(e.g., species, state of maturity, experience, current activity,
reproductive state, auditory sensitivity, time of day), as well as the
interplay between factors (e.g., Richardson et al., 1995; Wartzok et
al., 2003; Southall et al., 2007; Weilgart, 2007). Behavioral reactions
can vary not only among individuals but also within an individual,
depending on previous experience with a sound source, context, and
numerous other factors (Ellison et al., 2012), and can vary depending
on characteristics associated with the sound source (e.g., whether it
is moving or stationary, number of sources, distance from the source).
Please see Appendices B-C of Southall et al. (2007) for a review of
studies involving marine mammal behavioral responses to sound.
Habituation can occur when an animal's response to a stimulus wanes
with repeated exposure, usually in the absence of unpleasant associated
events (Wartzok et al., 2003). Animals are most likely to habituate to
sounds that are predictable and unvarying. It is important to note that
habituation is appropriately considered as a ``progressive reduction in
response to stimuli that are perceived as neither aversive nor
beneficial,'' rather than as, more generally, moderation in response to
human disturbance (Bejder et al., 2009). The opposite process is
sensitization, when an unpleasant experience leads to subsequent
responses, often in the form of avoidance, at a lower level of
exposure. As noted, behavioral state may affect the type of response.
For example, animals that are resting may show greater behavioral
change in response to disturbing sound levels than animals that are
highly motivated to remain in an area for feeding (Richardson et al.,
1995; NRC, 2003; Wartzok et al., 2003). Controlled experiments with
captive marine mammals have showed pronounced behavioral reactions,
including avoidance of loud sound sources (Ridgway et al., 1997;
Finneran et al., 2003). Observed responses of wild marine mammals to
loud pulsed sound sources (typically airguns or acoustic harassment
devices) have been varied but often consist of avoidance behavior or
other behavioral changes suggesting discomfort (Morton and Symonds,
2002; see also Richardson et al., 1995; Nowacek et al., 2007). However,
many delphinids approach low-frequency airgun source vessels with no
apparent discomfort or obvious behavioral change
[[Page 70301]]
(e.g., Barkaszi et al., 2012), indicating the importance of frequency
output in relation to the species' hearing sensitivity.
Available studies show wide variation in response to underwater
sound; therefore, it is difficult to predict specifically how any given
sound in a particular instance might affect marine mammals perceiving
the signal. If a marine mammal does react briefly to an underwater
sound by changing its behavior or moving a small distance, the impacts
of the change are unlikely to be significant to the individual, let
alone the stock or population. However, if a sound source displaces
marine mammals from an important feeding or breeding area for a
prolonged period, impacts on individuals and populations could be
significant (e.g., Lusseau and Bejder, 2007; Weilgart, 2007; NRC,
2005). However, there are broad categories of potential response, which
we describe in greater detail here, that include alteration of dive
behavior, alteration of foraging behavior, effects to breathing,
interference with or alteration of vocalization, avoidance, and flight.
Changes in dive behavior can vary widely and may consist of
increased or decreased dive times and surface intervals as well as
changes in the rates of ascent and descent during a dive (e.g., Frankel
and Clark, 2000; Costa et al., 2003; Ng and Leung, 2003; Nowacek et
al.; 2004; Goldbogen et al., 2013a, 2013b). Variations in dive behavior
may reflect interruptions in biologically significant activities (e.g.,
foraging) or they may be of little biological significance. The impact
of an alteration to dive behavior resulting from an acoustic exposure
depends on what the animal is doing at the time of the exposure and the
type and magnitude of the response.
Disruption of feeding behavior can be difficult to correlate with
anthropogenic sound exposure, so it is usually inferred by observed
displacement from known foraging areas, the appearance of secondary
indicators (e.g., bubble nets or sediment plumes), or changes in dive
behavior. As for other types of behavioral response, the frequency,
duration, and temporal pattern of signal presentation, as well as
differences in species sensitivity, are likely contributing factors to
differences in response in any given circumstance (e.g., Croll et al.,
2001; Nowacek et al.; 2004; Madsen et al., 2006; Yazvenko et al.,
2007). A determination of whether foraging disruptions incur fitness
consequences would require information on or estimates of the energetic
requirements of the affected individuals and the relationship between
prey availability, foraging effort and success, and the life history
stage of the animal.
Variations in respiration naturally vary with different behaviors
and alterations to breathing rate as a function of acoustic exposure
can be expected to co-occur with other behavioral reactions, such as a
flight response or an alteration in diving. However, respiration rates
in and of themselves may be representative of annoyance or an acute
stress response. Various studies have shown that respiration rates may
either be unaffected or could increase, depending on the species and
signal characteristics, again highlighting the importance of
understanding species differences in the tolerance of underwater noise
when determining the potential for impacts resulting from anthropogenic
sound exposure (e.g., Kastelein et al., 2001, 2005, 2006; Gailey et
al., 2007; Gailey et al., 2016).
Marine mammals vocalize for different purposes and across multiple
modes, such as whistling, echolocation click production, calling, and
singing. Changes in vocalization behavior in response to anthropogenic
noise can occur for any of these modes and may result from a need to
compete with an increase in background noise or may reflect increased
vigilance or a startle response. For example, in the presence of
potentially masking signals, humpback whales and killer whales have
been observed to increase the length of their songs (Miller et al.,
2000; Foote et al., 2004), while right whales have been observed to
shift the frequency content of their calls upward while reducing the
rate of calling in areas of increased anthropogenic noise (Parks et
al., 2007). In some cases, animals may cease sound production during
production of aversive signals (Bowles et al., 1994).
Avoidance is the displacement of an individual from an area or
migration path as a result of the presence of a sound or other
stressors, and is one of the most obvious manifestations of disturbance
in marine mammals (Richardson et al., 1995). For example, gray whales
are known to change direction--deflecting from customary migratory
paths--in order to avoid noise from airgun surveys (Malme et al.,
1984). Avoidance may be short-term, with animals returning to the area
once the noise has ceased (e.g., Bowles et al., 1994; Goold, 1996;
Stone et al., 2000; Morton and Symonds, 2002; Gailey et al., 2007).
Longer-term displacement is possible, however, which may lead to
changes in abundance or distribution patterns of the affected species
in the affected region if habituation to the presence of the sound does
not occur (e.g., Blackwell et al., 2004; Bejder et al., 2006; Teilmann
et al., 2006).
A flight response is a dramatic change in normal movement to a
directed and rapid movement away from the perceived location of a sound
source. The flight response differs from other avoidance responses in
the intensity of the response (e.g., directed movement, rate of
travel). Relatively little information on flight responses of marine
mammals to anthropogenic signals exist, although observations of flight
responses to the presence of predators have occurred (Connor and
Heithaus, 1996). The result of a flight response could range from
brief, temporary exertion and displacement from the area where the
signal provokes flight to, in extreme cases, marine mammal strandings
(Evans and England, 2001). However, it should be noted that response to
a perceived predator does not necessarily invoke flight (Ford and
Reeves, 2008), and whether individuals are solitary or in groups may
influence the response.
Behavioral disturbance can also impact marine mammals in more
subtle ways. Increased vigilance may result in costs related to
diversion of focus and attention (i.e., when a response consists of
increased vigilance, it may come at the cost of decreased attention to
other critical behaviors such as foraging or resting). These effects
have generally not been demonstrated for marine mammals, but studies
involving fish and terrestrial animals have shown that increased
vigilance may substantially reduce feeding rates (e.g., Beauchamp and
Livoreil, 1997; Fritz et al., 2002; Purser and Radford, 2011). In
addition, chronic disturbance can cause population declines through
reduction of fitness (e.g., decline in body condition) and subsequent
reduction in reproductive success, survival, or both (e.g., Harrington
and Veitch, 1992; Daan et al., 1996; Bradshaw et al., 1998). However,
Ridgway et al. (2006) reported that increased vigilance in bottlenose
dolphins exposed to sound over a five-day period did not cause any
sleep deprivation or stress effects.
Many animals perform vital functions, such as feeding, resting,
traveling, and socializing, on a diel cycle (24-hour cycle). Disruption
of such functions resulting from reactions to stressors such as sound
exposure are more likely to be significant if they last more than one
diel cycle or recur on subsequent days (Southall et al., 2007).
Consequently, a behavioral response lasting less than one day and not
recurring on subsequent days is not
[[Page 70302]]
considered particularly severe unless it could directly affect
reproduction or survival (Southall et al., 2007). Note that there is a
difference between multi-day substantive behavioral reactions and
multi-day anthropogenic activities. For example, just because an
activity lasts for multiple days does not necessarily mean that
individual animals are either exposed to activity-related stressors for
multiple days or, further, exposed in a manner resulting in sustained
multi-day substantive behavioral responses.
Stress Responses--An animal's perception of a threat may be
sufficient to trigger stress responses consisting of some combination
of behavioral responses, autonomic nervous system responses,
neuroendocrine responses, or immune responses (e.g., Seyle, 1950;
Moberg, 2000). In many cases, an animal's first and sometimes most
economical (in terms of energetic costs) response is behavioral
avoidance of the potential stressor. Autonomic nervous system responses
to stress typically involve changes in heart rate, blood pressure, and
gastrointestinal activity. These responses have a relatively short
duration and may or may not have a significant long-term effect on an
animal's fitness.
Neuroendocrine stress responses often involve the hypothalamus-
pituitary-adrenal system. Virtually all neuroendocrine functions that
are affected by stress--including immune competence, reproduction,
metabolism, and behavior--are regulated by pituitary hormones. Stress-
induced changes in the secretion of pituitary hormones have been
implicated in failed reproduction, altered metabolism, reduced immune
competence, and behavioral disturbance (e.g., Moberg, 1987; Blecha,
2000). Increases in the circulation of glucocorticoids are also equated
with stress (Romano et al., 2004).
The primary distinction between stress (which is adaptive and does
not normally place an animal at risk) and ``distress'' is the cost of
the response. During a stress response, an animal uses glycogen stores
that can be quickly replenished once the stress is alleviated. In such
circumstances, the cost of the stress response would not pose serious
fitness consequences. However, when an animal does not have sufficient
energy reserves to satisfy the energetic costs of a stress response,
energy resources must be diverted from other functions. This state of
distress will last until the animal replenishes its energetic reserves
sufficient to restore normal function.
Relationships between these physiological mechanisms, animal
behavior, and the costs of stress responses are well-studied through
controlled experiments and for both laboratory and free-ranging animals
(e.g., Holberton et al., 1996; Hood et al., 1998; Jessop et al., 2003;
Krausman et al., 2004; Lankford et al., 2005). Stress responses due to
exposure to anthropogenic sounds or other stressors and their effects
on marine mammals have also been reviewed (Fair and Becker, 2000;
Romano et al., 2002b) and, more rarely, studied in wild populations
(e.g., Romano et al., 2002a). For example, Rolland et al. (2012) found
that noise reduction from reduced ship traffic in the Bay of Fundy was
associated with decreased stress in North Atlantic right whales. These
and other studies lead to a reasonable expectation that some marine
mammals will experience physiological stress responses upon exposure to
acoustic stressors and that it is possible that some of these would be
classified as ``distress.'' In addition, any animal experiencing TTS
would likely also experience stress responses (NRC, 2003).
Auditory Masking--Sound can disrupt behavior through masking, or
interfering with, an animal's ability to detect, recognize, or
discriminate between acoustic signals of interest (e.g., those used for
intraspecific communication and social interactions, prey detection,
predator avoidance, navigation) (Richardson et al., 1995; Erbe et al.,
2016). Masking occurs when the receipt of a sound is interfered with by
another coincident sound at similar frequencies and at similar or
higher intensity, and may occur whether the sound is natural (e.g.,
snapping shrimp, wind, waves, precipitation) or anthropogenic (e.g.,
shipping, sonar, seismic exploration) in origin. The ability of a noise
source to mask biologically important sounds depends on the
characteristics of both the noise source and the signal of interest
(e.g., signal-to-noise ratio, temporal variability, direction), in
relation to each other and to an animal's hearing abilities (e.g.,
sensitivity, frequency range, critical ratios, frequency
discrimination, directional discrimination, age or TTS hearing loss),
and existing ambient noise and propagation conditions.
Under certain circumstances, marine mammals experiencing
significant masking could also be impaired from maximizing their
performance fitness in survival and reproduction. Therefore, when the
coincident (masking) sound is man-made, it may be considered harassment
when disrupting or altering critical behaviors. It is important to
distinguish TTS and PTS, which persist after the sound exposure, from
masking, which occurs during the sound exposure. Because masking
(without resulting in TS) is not associated with abnormal physiological
function, it is not considered a physiological effect, but rather a
potential behavioral effect.
The frequency range of the potentially masking sound is important
in determining any potential behavioral impacts. For example, low-
frequency signals may have less effect on high-frequency echolocation
sounds produced by odontocetes but are more likely to affect detection
of mysticete communication calls and other potentially important
natural sounds such as those produced by surf and some prey species.
The masking of communication signals by anthropogenic noise may be
considered as a reduction in the communication space of animals (e.g.,
Clark et al., 2009) and may result in energetic or other costs as
animals change their vocalization behavior (e.g., Miller et al., 2000;
Foote et al., 2004; Parks et al., 2007; Di Iorio and Clark, 2009; Holt
et al., 2009). Masking can be reduced in situations where the signal
and noise come from different directions (Richardson et al., 1995),
through amplitude modulation of the signal, or through other
compensatory behaviors (Houser and Moore, 2014). Masking can be tested
directly in captive species (e.g., Erbe, 2008), but in wild populations
it must be either modeled or inferred from evidence of masking
compensation. There are few studies addressing real-world masking
sounds likely to be experienced by marine mammals in the wild (e.g.,
Branstetter et al., 2013).
Masking affects both senders and receivers of acoustic signals and
can potentially have long-term chronic effects on marine mammals at the
population level as well as at the individual level. Low-frequency
ambient sound levels have increased by as much as 20 dB (more than
three times in terms of SPL) in the world's ocean from pre-industrial
periods, with most of the increase from distant commercial shipping
(Hildebrand, 2009). All anthropogenic sound sources, but especially
chronic and lower-frequency signals (e.g., from vessel traffic),
contribute to elevated ambient sound levels, thus intensifying masking.
Potential Effects of Hilcorp's Activity--As described previously
(see ``Description of the Specified Activity''), Hilcorp proposes to
build ice roads, install a pipeline, construct and operate a gravel
island using impact and vibratory pile driving, and drill for oil in
Foggy Island Bay. These activities
[[Page 70303]]
would occur under ice and open water conditions (with the exception of
ice roads). These activities have the potential to harass marine
mammals from acoustic disturbance (all species) and via human
disturbance/presence on ice (ice seals). There is also potential for
ice seals, specifically ringed seals, to be killed in the event a lair
is crushed during ice road construction and maintenance in undisturbed
areas after March 1, annually.
NMFS analyzed the potential effects of oil and gas activities,
including construction of a gravel island and associated
infrastructure, in its 2016 EIS on the Effects of Oil and Gas
Activities in the Arctic Ocean (NMFS, 2016; available at https://www.fisheries.noaa.gov/resource/document/effects-oil-and-gas-
activities-arctic-ocean-final-environmental-impact). Although that
document focuses on seismic exploration, there is a wealth of
information in that document on marine mammal impacts from
anthropogenic noise. More specific to the proposed project, BOEM
provides a more detailed analysis on the potential impacts of the
Liberty LDPI in its EIS on the Liberty Development and Production Plan,
Beaufort Sea, Alaska, on which NMFS was a cooperating agency (BOEM,
2018; available at https://www.boem.gov/Hilcorp-Liberty/). We refer to
those documents, specifically Chapter 4 of each of those documents, as
a comprehensive impact assessment but provide a summary and
complementary analysis here.
The effects of pile driving on marine mammals are dependent on
several factors, including the size, type, and depth of the animal; the
depth, intensity, and duration of the pile driving sound; the depth of
the water column; the substrate of the habitat; the standoff distance
between the pile and the animal; and the sound propagation properties
of the environment. With both types of pile driving, it is likely that
the onset of pile driving could result in temporary, short term changes
in an animal's typical behavioral patterns and/or avoidance of the
affected area. These behavioral changes may include (as summarized in
Richardson et al., 1995): changing durations of surfacing and dives,
number of blows per surfacing, or moving direction and/or speed;
reduced/increased vocal activities; changing/cessation of certain
behavioral activities (such as socializing or feeding); visible startle
response or aggressive behavior (such as tail/fluke slapping or jaw
clapping); avoidance of areas where sound sources are located; and/or
flight responses.
For all noise-related activities, bowhead and gray whales are not
anticipated to be exposed to noise above NMFS harassment threshold
often. As previously described, Hilcorp aims to conduct all pile
driving during the ice-covered season, as was done at Northstar;
however, they are allowing for unforeseen scheduling delays. Bowheads
are not present near LDPI during the winter and are not normally found
in the development area during mid-summer (July through mid-August)
when the whales are further east in the Canadian Beaufort. Therefore,
there are no impacts on foraging habitat for bowhead whales during mid-
summer. Starting in late August and continuing until late October,
bowheads may be exposed to sounds from the proposed activities at LDPI
or may encounter vessel traffic to and from the island. It is unlikely
that any whales would be displaced from sounds generated by activities
at the LDPI due to their distance from the offshore migrating whales,
and the effects of buffering from the barrier islands. Any displacement
would be subtle and involve no more than a small proportion of the
passing bowheads, likely less than that found at Northstar (Richardson,
2003, 2004; Mcdonald et al., 2012). This is due to the baffling-effect
of the barrier island between the construction activity and the main
migratory pathway of bowhead whales. Moreover, mitigation such as
avoiding pile driving during the fall bowhead whale hunt further
reduces potential for harassment as whales are migrating offshore.
Ongoing activities such as drilling could harass marine mammals;
however, drilling sounds from artificial islands are relatively low. As
summarized in Richardson et al. (1995), beluga whales (the cetacean
most likely to occur in Foggy Island Bay) are often observed near
drillsites within 100 to 150 m (328.1 to 492.1 ft) from artificial
islands. Drilling operations at Northstar facility during the open-
water season resulted in brief, minor localized effects on ringed seals
with no consequences to ringed seal populations (Richardson and
Williams, 2004). Adult ringed seals seem to tolerate drilling
activities. Brewer et al. (1993) noted ringed seals were the most
common marine mammal sighted and did not seem to be disturbed by
drilling operations at the Kuvlum 1 project in the Beaufort Sea.
Southall et al. (2007) reviewed literature describing responses of
pinnipeds to continuous sound and reported that the limited data
suggest exposures between ~90 and 140 dB re 1 [mu]Pa generally do not
appear to induce strong behavioral responses in pinnipeds exposed to
continuous sounds in water. Hilcorp will conduct acoustic monitoring
during drilling to determine if future incidental take authorizations
are warranted from LDPI operation.
The biological significance of many of these behavioral
disturbances is difficult to predict, especially if the detected
disturbances appear minor. However, the consequences of behavioral
modification could be expected to be biologically significant if the
change affects growth, survival, or reproduction. Significant
behavioral modifications that could lead to effects on growth,
survival, or reproduction, such as drastic changes in diving/surfacing
patterns or significant habitat abandonment are extremely unlikely in
this area (i.e., shallow waters in modified industrial areas).
The onset of behavioral disturbance from anthropogenic sound
depends on both external factors (characteristics of sound sources and
their paths) and the specific characteristics of the receiving animals
(hearing, motivation, experience, demography) and is difficult to
predict (Southall et al., 2007).
Whether impact or vibratory driving, sound sources would be active
for relatively short durations, with relation to the durations animals
use sound (either emitting or receiving) on a daily basis, and over a
small spatial scale relative to marine mammal ranges. Therefore, the
potential impacts from masking are limited in both time and space.
Further, the frequencies output of pile driving are low relative to the
range of frequencies used by most species for vital life functions such
as communication or foraging. In summary, we expect some masking to
occur; however, the biological impacts of any potential masking are
anticipated to be negligible. Finally, any masking that might rise to
Level B harassment under the MMPA would occur concurrently within the
zones of behavioral harassment already estimated for vibratory and
impact pile driving, and which have already been taken into account in
the exposure analysis.
Oil Spills
During the life of the regulations, Hilcorp would be actively
drilling for crude oil in Foggy Island Bay and transporting that oil
via a single-phase subsea pipe-in-pipe pipeline from the LDPI to shore,
where an above-ground pipeline will transport crude to the existing
Badami pipeline. From there, crude will be transported to the Endicott
Sales Oil Pipeline, which ties into Pump Station 1 of the TransAlaska
Pipeline
[[Page 70304]]
System (TAPS) for eventual delivery to a refinery. Whenever oil is
being extracted or transported, there is potential for a spill.
Accidental oil spills have a varying potential to occur and with
varying impacts on marine mammals. For example, if a spill or pipeline
leak occurs during the winter, oil would be trapped by the ice.
However, response may be more difficult due in part to the presence of
ice. If a spill or leak occurs during the open-water season, oil may
disperse more widely; however, response time may be more prompt. Spills
may also be large or small. Small spills are defined as spills of less
than 1,000 barrels (bbls), and a large spill is greater than 1,000
bbls. For reference, 1 bbl equates to 42 gallons.
Based on BOEM's oil spill analyses in its EIS, the only sized
spills that are reasonably likely to occur in association with the
proposed action are small spills (<1,000 bbls) (BOEM, 2017a). Small
spills, although accidental, occur during oil and gas activities with
generally routine frequency and are considered likely to occur during
development, production, and/or decommissioning activities associated
with the proposed action. BOEM estimates about 70 small spills, most of
which would be less than 10 bbls, would occur over the life of the
Liberty Project. Small crude oil spills would not likely occur before
drilling operations begin. Small refined oil spills may occur during
development, production, and decommissioning. The majority of small
spills are likely to occur during the approximate 22-year production
period, which is an average of about 3 spills per year.
The majority of small spills would be contained on the proposed
LDPI or landfast ice (during winter). BOEM anticipates that small
refined spills that reach the open water would be contained by booms or
absorbent pads; these small spills would also evaporate and disperse
within hours to a few days. A 3 bbl refined oil spill during summer is
anticipated to evaporate and disperse within 24 hours, and a 200 bbl
refined oil spill during summer is anticipated to evaporate and
disperse within 3 days (BOEM, 2017a).
A large spill is a statistically unlikely event. The average number
of large spills for the proposed action was calculated by multiplying
the spill rate (Bercha International Inc., 2016; BOEM, 2017a), by the
estimated barrels produced (0.11779 bbl or 117.79 Million Barrels). By
adding the mean number of large spills from the proposed LDPI and wells
(~0.0043) and from pipelines (~0.0024), a mean total of 0.0067 large
spills were calculated for the proposed action. Based on the mean spill
number, a Poisson distribution indicates there is a 99.33 percent
chance that no large spill occurs over the development and production
phases of the project, and a 0.67 percent chance of one or more large
spills occurring over the same period. The statistical distribution of
large spills and gas releases shows that it is much more likely that no
large spills or releases occur than that one or more occur over the
life of the project. However, a large spill has the potential to
seriously harm ESA-listed species and their environment. Assuming one
large spill occurs instead of zero allows BOEM to more fully estimate
and describe potential environmental effects (BOEM, 2017a).
Hilcorp is currently developing its oil spill response plan in
coordination with the Bureau of Safety and Environmental Enforcement
(BSEE) who must approve the plan. BSEE oversees oil spill planning and
preparedness for oil and gas exploration, development, and production
facilities in both state and Federal offshore waters of the U.S. NMFS
provided BSEE with its recommended marine mammal oil spill response
protocols available at https://www.fisheries.noaa.gov/resource/
document/pinniped-and-cetacean-oil-spill-response-guidelines. NMFS has
provided BSEE with recommended marine mammal protocols should a spill
occur. BSEE has indicated that NMFS will have an opportunity to provide
comments on Hilcorp's plan during a Federal agency public comment
period. As noted above, Hilcorp did not request, and NMFS is not
proposing to authorize, takes of marine mammals incidental to oil
spills. NMFS does not authorize incidental takes from oil spills under
section 101(a)(5)(A) of the MMPA in general, and oil spills are not
part of the specified activity in this case.
Cetaceans
While direct mortality of cetaceans is unlikely, exposure to
spilled oil could lead to skin irritation, baleen fouling (which might
reduce feeding efficiency), respiratory distress from inhalation of
hydrocarbon vapors, consumption of some contaminated prey items, and
temporary displacement from contaminated feeding areas. Geraci and St.
Aubin (1990) summarize the effects of oil on marine mammals, and
Bratton et al. (1993) provides a synthesis of knowledge of oil effects
on bowhead whales. The number of whales that might be contacted by a
spill would depend on the size, timing, and duration of the spill.
Whales may not avoid oil spills, and some have been observed feeding
within oil slicks (Goodale et al., 1981).
The potential effects on cetaceans are expected to be less than
those on seals (described later in this section of the document).
Cetaceans tend to occur well offshore where cleanup activities (in the
open-water season) are unlikely to be as concentrated. Also, cetaceans
are transient and, during the majority of the year, absent from the
area. Further, drilling would be postponed during the bowhead whale
hunt every fall; therefore, the risk to cetaceans during this time,
when marine mammal presence and subsistence use is high, has been fully
mitigated.
Pinnipeds
Ringed, bearded, and spotted seals are present in open-water areas
during summer and early autumn, and ringed seals remain in the area
through the ice-covered season. Therefore, an oil spill from LDPI or
its pipeline could affect seals. Any oil spilled under the ice also has
the potential to directly contact seals. The most relevant data of
pinnipeds exposed to oil is from the Exxon Valdez oil spill (EVOS).
The largest documented impact of a spill, prior to the EVOS, was on
young seals in January in the Gulf of St. Lawrence (St. Aubin, 1990).
Intensive and long-term studies were conducted after the EVOS in
Alaska. There may have been a long-term decline of 36 percent in
numbers of molting harbor seals at oiled haul-out sites in Prince
William Sound following EVOS (Frost et al., 1994a). However, in a
reanalysis of those data and additional years of surveys, along with an
examination of assumptions and biases associated with the original
data, Hoover-Miller et al. (2001) concluded that the EVOS effect had
been overestimated. Harbor seal pup mortality at oiled beaches was 23%
to 26%, which may have been higher than natural mortality, although no
baseline data for pup mortality existed prior to EVOS (Frost et al.,
1994a).
Adult seals rely on a layer of blubber for insulation, and oiling
of the external surface does not appear to have adverse
thermoregulatory effects (Kooyman et al., 1976, 1977; St. Aubin, 1990).
However, newborn seal pups rely on their fur for insulation. Newborn
ringed seal pups in lairs on the ice could be contaminated through
contact with oiled mothers. There is the potential that newborn ringed
seal pups that were contaminated with oil could die from hypothermia.
Further, contact with oil on the external surfaces can potentially
cause increased stress and irritation of the eyes of ringed seals
(Geraci and Smith, 1976; St. Aubin, 1990). These
[[Page 70305]]
effects seemed to be temporary and reversible, but continued exposure
of eyes to oil could cause permanent damage (St. Aubin, 1990). Corneal
ulcers and abrasions, conjunctivitis, and swollen nictitating membranes
were observed in captive ringed seals placed in crude oil-covered water
(Geraci and Smith, 1976), and in seals in the Antarctic after an oil
spill (Lillie, 1954).
Marine mammals can ingest oil if their food is contaminated. Oil
can also be absorbed through the respiratory tract (Geraci and Smith,
1976; Engelhardt et al., 1977). Some of the ingested oil is voided in
vomit or feces but some is absorbed and could cause toxic effects
(Engelhardt, 1981). When returned to clean water, contaminated animals
can depurate this internal oil (Engelhardt, 1978, 1982, 1985). In
addition, seals exposed to an oil spill are unlikely to ingest enough
oil to cause serious internal damage (Geraci and St. Aubin, 1980,
1982).
Since ringed seals are found year-round in the U.S. Beaufort Sea
and more specifically in the project area, an oil spill at any time of
year could potentially have effects on ringed seals. However, they are
more widely dispersed during the open-water season. Spotted seals are
unlikely to be found in the project area during late winter and spring.
Therefore, they are more likely to be affected by a spill in the summer
or fall seasons. Bearded seals typically overwinter south of the
Beaufort Sea. However, some have been reported around Northstar during
early spring (Moulton et al., 2003b).
Oil Spill Cleanup Activities
Oil spill cleanup activities could increase disturbance effects on
either whales or seals, causing temporary disruption and possible
displacement (BOEM, 2018). General issues related to oil spill cleanup
activities are discussed earlier in this section for cetaceans. In the
event of a large spill contacting and extensively oiling coastal
habitats, the presence of response staff, equipment, and the many
aircraft involved in the cleanup could (depending on the time of the
spill and the cleanup) potentially displace seals. If extensive cleanup
operations occur in the spring, they could cause increased stress and
reduced pup survival of ringed seals. Oil spill cleanup activity could
exacerbate and increase disturbance effects on subsistence species,
cause localized displacement of subsistence species, and alter or
reduce access to those species by hunters. On the other hand, the
displacement of marine mammals away from oil-contaminated areas by
cleanup activities would reduce the likelihood of direct contact with
oil. Impacts to subsistence uses of marine mammals are discussed later
in this document (see the ``Impact on Availability of Affected Species
or Stock for Taking for Subsistence Uses'' section).
Potential Take From Oil Spills
Hilcorp did not request, and NMFS is not proposing to authorize,
takes of marine mammals incidental to oil spills. Should an oil spill
occur and marine mammals are killed, injured, or harassed by the spill,
the ``taking'' would be unauthorized. However, NMFS is including
mitigation and reporting measures within these regulations to minimize
risk to marine mammals. Should an oil spill occur at the drill site and
that oil enter the marine environment such that marine mammals are at
risk of exposure, NMFS has included a mitigation measure that Hilcorp
notify NMFS immediately and cease drilling until NMFS can assess the
severity of the spill and potential impacts to marine mammals. Should
the pipeline leak, crude oil transport via the pipeline would also
cease immediately until the pipeline is repaired. In the case of any
spill, Hilcorp would immediately initiate communication and response
protocol per its Oil Spill Response Plan. Finally, Hilcorp must
maintain the frequency of oil spill response training at no less than
one two-hour session per week.
Anticipated Effects on Marine Mammal Habitat
We described the potential impacts to marine mammal habitat,
pathways by which the project could affect marine mammal prey and the
corresponding potential impact on marine mammals in the proposed rule.
No new data has been released or was described in public comments to
warrant any additional analysis. Therefore, our analysis remains the
same and therefore we do not repeat it here.
Estimated Take
This section provides an estimate of the number of incidental takes
anticipated to result from the specified activity and analyzed in this
final rule, and which may be authorized in the associated LOA, which
will inform both NMFS' consideration of ``small numbers'' and the
negligible impact determination. As noted in the Changes from Proposed
to Final Rule section above, we made minor adjustments to this section
based on public comment. None of these changes were substantial as many
were related to clarity or only slightly increased takes to account for
group size; hence, none of these modifications affected our required
findings.
Except with respect to certain activities not pertinent here,
section 3(18) of the MMPA defines ``harassment'' as: Any act of
pursuit, torment, or annoyance which (i) has the potential to injure a
marine mammal or marine mammal stock in the wild (Level A harassment);
or (ii) has the potential to disturb a marine mammal or marine mammal
stock in the wild by causing disruption of behavioral patterns,
including, but not limited to, migration, breathing, nursing, breeding,
feeding, or sheltering (Level B harassment).
Authorized takes would primarily be by Level B harassment, as use
of pile hammers, drill rigs, and ice-based equipment (e.g., augers,
trucks) have the potential to result in disruption of behavioral
patterns for individual marine mammals. There is also some potential
for auditory injury (Level A harassment) to result during pile driving.
The mitigation and monitoring measures are expected to minimize the
severity of such takes to the extent practicable.
No mortality or serious injury is anticipated as a result of
exposure to acoustic sources; however, mortality and serious injury of
ringed seals may occur from ice road construction, use, and maintenance
conducted after March 1, annually. Below we describe how we estimated
mortality and serious injury from ice road work followed by a detailed
acoustic harassment estimation method.
Mortality/Serious Injury (Ice Seals)
The only species with the potential to incur serious injury or
mortality during the proposed project are ringed seals during ice road
construction, use, and maintenance. Other ice seal species are not
known to use ice roads within the action area. As described in the
Description of Marine Mammals section, pregnant ringed seals establish
lairs in shorefast sea ice beginning in early March where pups are born
and nursed throughout spring (March through May).
As described in the Potential Effects of the Specified Activity on
Marine Mammals and Their Habitat section above, there have been only
three documented interactions with ringed seals despite over 20 years
of ice road construction on the North Slope; one mortality in 1998 and
two non-lethal interactions in 2018. All three animals involved were
seal pups in or near their lairs. The two recent interactions in 2018
led NMFS to work with the companies involved in the interactions,
including Hilcorp, to better understand
[[Page 70306]]
the circumstances behind the interactions and to develop a list of BMPs
designed to avoid and minimize potential harassment. Hilcorp has
adopted these BMPs (see Mitigation and Monitoring section); however,
the potential for mortality remains, albeit low. Because lairs can
include both a pup and its mother, though interactions with ringed
seals are relatively uncommon, NMFS authorizes the taking, by mortality
or serious injury, of two ringed seals over the course of five years of
ice road construction.
Acoustic Harassment
Generally speaking, we estimate takes by considering: (1) Acoustic
thresholds above which NMFS believes the best available science
indicates marine mammals will be behaviorally harassed or incur some
degree of permanent hearing impairment; (2) the area or volume of water
that will be ensonified above these levels in a day; (3) the density or
occurrence of marine mammals within these ensonified areas; and, (4)
the number of days of activities. We note that while these basic
factors can contribute to a basic calculation to provide an initial
prediction of takes, additional information that can qualitatively
inform take estimates is also sometimes available (e.g., previous
monitoring results or average group size). Below, we describe the
factors considered here in more detail and present the take estimate.
Acoustic Thresholds
Using the best available science, NMFS has developed acoustic
thresholds that identify the received level of underwater sound above
which exposed marine mammals would be reasonably expected to be
behaviorally harassed (equated to Level B harassment) or to incur PTS
of some degree (equated to Level A harassment).
Level B Harassment for non-explosive sources--Though significantly
driven by received level, the onset of behavioral disturbance from
anthropogenic noise exposure is also informed to varying degrees by
other factors related to the source (e.g., frequency, predictability,
duty cycle), the environment (e.g., bathymetry), and the receiving
animals (e.g., hearing, motivation, experience, demography, behavioral
context) and can be difficult to predict (Southall et al., 2007,
Ellison et al., 2012). Based on what the available science indicates
and the practical need to use a threshold based on a factor that is
both predictable and measurable for most activities, NMFS uses a
generalized acoustic threshold based on received level to estimate the
onset of Level B harassment. NMFS predicts that marine mammals are
likely to be harassed in a manner we consider Level B harassment when
exposed to underwater anthropogenic noise above received levels of 120
dB re 1 [mu]Pa (rms) for continuous (e.g., vibratory pile-driving,
drilling) and above 160 dB re 1 [mu]Pa (rms) for non-explosive
impulsive (e.g., seismic airguns) or intermittent (e.g., scientific
sonar) sources.
Hilcorp's Liberty Project includes the use of continuous, non-
impulsive (vibratory pile driving, drilling, auguring) and
intermittent, impulsive (impact pile driving) sources, and therefore
the 120 and 160 dB re 1 [mu]Pa (rms) thresholds are applicable.
Level A harassment for non-explosive sources--NMFS' Technical
Guidance for Assessing the Effects of Anthropogenic Sound on Marine
Mammal Hearing (Version 2.0) (Technical Guidance, 2018) identifies dual
criteria to assess auditory injury (Level A harassment) to five
different marine mammal groups (based on hearing sensitivity) as a
result of exposure to noise from two different types of sources
(impulsive or non-impulsive). Hilcorp's proposed activity includes the
use of impulsive (e.g., impact pile driving) and non-impulsive (e.g.,
vibratory pile driving, slope shaping, trenching) sources.
These thresholds are provided in Table 3. The references, analysis,
and methodology used in the development of the thresholds are described
in NMFS 2018 Technical Guidance, which may be accessed at https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-
acoustic-technical-guidance.
Table 3--Thresholds Identifying the Onset of Permanent Threshold Shift
----------------------------------------------------------------------------------------------------------------
PTS onset acoustic thresholds * (received level)
Hearing group ------------------------------------------------------------------------
Impulsive Non-impulsive
----------------------------------------------------------------------------------------------------------------
Low-Frequency (LF) Cetaceans........... Cell 1: Lpk,flat: 219 dB; Cell 2: LE,LF,24h: 199 dB.
LE,LF,24h: 183 dB.
Mid-Frequency (MF) Cetaceans........... Cell 3: Lpk,flat: 230 dB; Cell 4: LE,MF,24h: 198 dB.
LE,MF,24h: 185 dB.
High-Frequency (HF) Cetaceans.......... Cell 5: Lpk,flat: 202 dB; Cell 6: LE,HF,24h: 173 dB.
LE,HF,24h: 155 dB.
Phocid Pinnipeds (PW) (Underwater)..... Cell 7: Lpk,flat: 218 dB; Cell 8: LE,PW,24h: 201 dB.
LE,PW,24h: 185 dB.
Otariid Pinnipeds (OW) (Underwater).... Cell 9: Lpk,flat: 232 dB; Cell 10: LE,OW,24h: 219 dB.
LE,OW,24h: 203 dB.
----------------------------------------------------------------------------------------------------------------
* Dual metric acoustic thresholds for impulsive sounds: Use whichever results in the largest isopleth for
calculating PTS onset. If a non-impulsive sound has the potential to exceed the peak sound pressure level
thresholds associated with impulsive sounds, these thresholds should also be considered.
Note: Peak sound pressure (Lpk) has a reference value of 1 [micro]Pa, and cumulative sound exposure level (LE)
has a reference value of 1[micro]Pa\2\s. In this Table, thresholds are abbreviated to reflect American
National Standards Institute standards (ANSI 2013). However, peak sound pressure is defined by ANSI as
incorporating frequency weighting, which is not the intent for this Technical Guidance. Hence, the subscript
``flat'' is being included to indicate peak sound pressure should be flat weighted or unweighted within the
generalized hearing range. The subscript associated with cumulative sound exposure level thresholds indicates
the designated marine mammal auditory weighting function (LF, MF, and HF cetaceans, and PW and OW pinnipeds)
and that the recommended accumulation period is 24 hours. The cumulative sound exposure level thresholds could
be exceeded in a multitude of ways (i.e., varying exposure levels and durations, duty cycle). When possible,
it is valuable for action proponents to indicate the conditions under which these acoustic thresholds will be
exceeded.
Ensonified Area
Here, we describe operational and environmental parameters of the
activity that will feed into identifying the area ensonified above the
acoustic thresholds, which include source levels and transmission loss
coefficient.
In shallow water noise propagation is highly dependent on the
properties of the bottom and the surface, among other things.
Parameters such as depth and the bottom properties can vary with
distance from the source. There is a low-frequency cut-off related to
the water depth, below which energy is transferred directly into the
sea floor. Overall, the transmission loss in shallow water is a
combination of cylindrical spreading effects, bottom interaction
effects at lower frequencies and scattering losses at high frequencies.
To estimate ensonified area, Hilcorp used the parabolic
[[Page 70307]]
equation (PE) modelling algorithm RAMGeo (Collins, 1993) to calculate
the transmission loss between the source and the receiver (SLR, 2017).
The full modeling report, including details on modeling methodology and
procedure and ensonification area figures, can be found in the
Underwater and Airborne Noise Modelling Report attached as Appendix A
in Hilcorp's application. We provide a summary here.
RAMGeo is an efficient and reliable PE algorithm for solving range-
dependent acoustic problems with fluid seabed geo-acoustic properties.
The noise sources were assumed to be omnidirectional and modelled as
point sources. In practice many sources are directional, this
assumption is conservative. To estimate Level A harassment and Level B
harassment threshold distances, Hilcorp first obtained one-third octave
source spectral levels via reference spectral curves with their
subsequent corrections based on their corresponding overall source
levels. Table 4 contains estimated source levels and Appendix B in
Hilcorp's acoustic modeling report contains source spectrum shape used
in the model (SLR, 2018).
Table 4--Estimated Source Levels and Duration
--------------------------------------------------------------------------------------------------------------------------------------------------------
Underwater source levels (db
re: 1 [micro]Pa)
Activity -------------------------------- Airborne (db re: 20 [micro]Pa) Number of Maximum duration per day
Ice-covered Open-water piles per day
season season
--------------------------------------------------------------------------------------------------------------------------------------------------------
Pipeline installation (trucks on ice, 169.6-179.1 N/A 74.8-78 @100 m.................... N/A 12 hrs.
backhoe, ditchwitch).
Sheet pile--vibratory.................. 221 185 81 @100 m......................... 20 2.5 hrs.\1\
Sheet pile--impact..................... 235.7 210 93 @160 m......................... ............... 40 min.\2\
Conductor pipe-vibratory............... .............. .............. .................................. 16 2.5 hrs (proxy from sheet
piles).
Conductor pipes/foundation piles-- 171.7 196 .................................. 2 hrs.\3\
impact.
Slope shaping/armoring................. n/a 167 64.7 @100 m....................... n/a 9.6 hrs.
Drilling and production................ 170.5 151 80 @200 m......................... n/a 24 hrs.
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Estimated based on 20 piles per day, 7.5 min per pile.
\2\ Average duration estimate is 20 min per day.
\3\ Hilcorp estimates 440-6300 strikes per day.
Hilcorp relied on operational data from Northstar construction
activities to estimate LDPI construction activity methods and
durations. Greene et al. (2008) indicates impact pile driving at
Northstar was required only to finish off each pile after vibratory
driving it into the frozen material of old Seal Island. Since Liberty
will be a newly constructed gravel island, driving sheet piles should
be easier than was the case at Northstar. Impact sheet pile driving
therefore may not be required at Liberty and is included in the
application as a precaution. Hilcorp assumed approximately 2 minutes
and 100 strikes per pile with a maximum of 20 piles installed per day.
Blackwell et al. (2004a) observed impact pipe driving at Northstar. On
most days, one conductor pipe was driven in a day over a period of 5 to
8.5 hours. The longest day of observation was 10.5 hours in which time
two pipes were driven. The observation period each day included all
pipe driving time, but driving was never continuous during the entire
observation period. Hilcorp applied a correction factor to the
Northstar duration, assuming pipe driving at the LDPI would actually
occur for 20 percent of the total installation time logged at
Northstar.
The scenarios with theoretical potential for PTS onset are slope
shaping, vibratory driving, and impact pile driving and pipe driving
during the open-water season. Hilcorp did not model distances to PTS
thresholds during ice-covered conditions because no cetaceans are
present in the region during this time and noise levels are expected to
attenuate very rapidly under ice conditions. Hilcorp did not request,
nor does NMFS anticipate, takes by Level A harassment (PTS) during
island construction conducted under ice conditions. The following
discussion on PTS potential is limited to the open-water season.
Table 5 summarizes Hilcorp's modeled distances to NMFS PTS
thresholds using the maximum durations identified above (see also
Tables 16 through 18 in Appendix A of Hilcorp's application for shorter
durations). We note that marine mammals would have to be extremely
close to the island during slope shaping and pile driving for an
extended period of time to potentially incur PTS. We find these
durations at distance are highly unlikely and have concluded the
potential for PTS from slope shaping and vibratory pile driving for any
marine mammal hearing group does not exist. Table 6 summarizes
distances and ensonified areas to NMFS Level B harassment thresholds
during ice-covered and open water conditions.
Table 5--Radial Distances to NMFS Level A Harassment Thresholds and Ensonified Area During the Open-Water Season
----------------------------------------------------------------------------------------------------------------
Activity (duration) and distance to threshold (ensonified area)
Marine mammal hearing group -------------------------------------------------------------------------------
(species) Slope shaping (9.6 Vibratory sheet Impact sheet Impact pipe
hrs) piling (2.5 hrs) piling (40 min) driving (2 hrs)
----------------------------------------------------------------------------------------------------------------
Low frequency cetaceans <10 m (0 km\2\)... 50 m (164 ft)..... 1,940 (11.8 km\2\) 87 m (2.38 km\2\).
(bowhead, gray whales).
Mid frequency cetaceans n/a............... <10 m (0 km\2\)... 60 m (0.01 km\2\). 27 m (0.002
(belugas). km\2\).
[[Page 70308]]
Phocid Pinnipeds (bearded, <10 m (0 km\2\)... 20 m (66 ft)...... 526 m (0.87 km\2\) 240 m (0.18
ringed, spotted seals). km\2\).
----------------------------------------------------------------------------------------------------------------
Table 6--Radial Distances to NMFS Level B Harassment Thresholds and Ensonified Areas
----------------------------------------------------------------------------------------------------------------
Activity Ice-covered season Open-water season \1\ Airborne
----------------------------------------------------------------------------------------------------------------
Ice road construction and maintenance 170 m (0.09 km\2\)..... n/a.................... <15 m (<0.001 km\2\).
Pipeline construction................ 210 m (0.14km\2\)...... n/a....................
Sheet pile driving--vibratory........ 390 m (0.48 km\2\)..... 14,800 m (63.9 km\2\)
\2\.
Sheet pile driving--impact........... 90 m (0.03 km\2\)...... 2050 m (13.20 km\2\)... 100 m (0.031 km\2\).
Conductor pipe/foundation pile 11 m ( <0.01 km\2\).... 315 m (0.31 km\2\).....
driving--impact.
Slope shaping/armoring............... n/a.................... 1160 m (4.23 km\2\).... <15 m (<0.001 km\2\).
Helicopter (take-off/landing)........ n/a.................... n/a.................... 67 m (0.041 km\2\).
Drilling and Production.............. 230 m (0.17 km\2\)..... 55 m (<0.01 km\2\)..... 30 m (0.003 km\2\).
----------------------------------------------------------------------------------------------------------------
\1\ Open water modeling results in the proposed rule were presented as minimum, median and maximum distances to
the appropriate noise threshold across all depths calculated in the direction of maximum noise propagation
from the source, away from shore. For this final rule, NMFS determined the median distance was appropriate to
implement as the Level B harassment area. As in the proposed rule, these median distances were used to
estimate take.
\2\ The ensonified area considers the noise absorption effect of the McClure Islands.
Marine Mammal Occurrence
Each fall and summer, NMFS and BOEM conduct an aerial survey in the
Arctic, the Aerial Survey of Arctic Marine Mammals (ASAMM) surveys. The
goal of these surveys is to document the distribution and relative
abundance of bowhead, gray, right, fin and beluga whales and other
marine mammals in areas of potential oil and natural gas exploration,
development, and production activities in the Alaskan Beaufort and
northeastern Chukchi Seas. Traditionally, only fall surveys were
conducted but then, in 2011, the first dedicated summer survey effort
began in the ASAMM Beaufort Sea study area. Hilcorp used these ASAMM
surveys as the data source to estimate seasonal densities of cetaceans
(bowhead, gray and beluga whales) in the project area. The ASAMM
surveys are conducted within blocks that overlay the Beaufort and
Chukchi Seas oil and gas lease sale areas offshore of Alaska (Figure 6-
1 in Hilcorp's application), and provide sighting data for bowhead,
gray, and beluga whales during summer and fall months. During the
summer and fall, NMFS observed for marine mammals on effort for 10,993
km and 11,047 km, respectively, from 2011 through 2017 (Table 7). Data
from those surveys are used for this analysis. We note the location of
the proposed LDPI project is in ASAMM survey block 1; the inshore
boundary of this block terminates at the McClure Island group. It was
not until 2016 that on-effort surveys began inside the McClure Island
group (i.e., Foggy Island Bay) since bowhead whales, the focus of the
surveys, are not likely to enter the bay. No marine mammals have been
observed during ASAMM surveys in Foggy Island Bay. Therefore, the
density estimates provided here are an overestimate because they rely
on offshore surveys where marine mammals are concentrated.
Bowhead Whale
Summer and fall bowhead whale densities were calculated using the
results from ASAMM surveys from 2011 through 2017. The surveys provided
sightings and effort data by month and season (summer and fall), as
well as each survey block (Clarke et al., 2012, 2013a, 2014, 2015,
2017). Bowhead whale densities were calculated in a two-step approach;
they first calculated a sighting rate of whales per km, then they
multiplied the transect length by the effective strip width using the
modeled species-specific effective strip width for an aero commander
aircraft calculated by Ferguson and Clarke (2013). Where the effective
strip width is the half-strip width, it must be multiplied by 2 in
order to encompass both sides of the transect line. Thus whale density
was calculated as follows: Whales per km\2\ = whales per kilometer/(2 x
the effective strip width). The effective strip width for bowhead
whales was calculated to be 1.15 km (CV = 0.08). Table 7 contains
pooled data from 2011 through 2017 Block 1 ASAMM surveys and resulting
densities.
The resulting densities are expected to be overestimates for the
LDPI analysis because data is based on sighting effort outside the
barrier islands, and bowhead and gray whales rarely occur within the
barrier islands, while belugas also are found in higher abundance
outside of Foggy Island Bay.
Table 7--Bowhead Whale Sighting Data From 2011 Through 2017 and Resulting Densities
--------------------------------------------------------------------------------------------------------------------------------------------------------
Transect Number whale
Year Season Month effort (km) sighted whale/km whale/km\2\
--------------------------------------------------------------------------------------------------------------------------------------------------------
2011................................. Summer.................. Jul-Aug................ 346 1 0.003 0.001
Fall.................... Sept-Oct............... 1,476 24 0.016 0.007
2012................................. Summer.................. Jul-Aug................ 1,493 5 0.003 0.001
Fall.................... Sept-Oct............... 1,086 14 0.013 0.006
[[Page 70309]]
2013................................. Summer.................. Jul-Aug................ 1,582 21 0.013 0.006
Fall.................... Sept-Oct............... 1,121 21 0.019 0.008
2014................................. Summer.................. Jul -Aug............... 1,393 17 0.012 0.005
Fall.................... Sept-Oct............... 1,538 79 0.051 0.022
2015................................. Summer.................. Jul-Aug................ 1,262 15 0.012 0.005
Fall.................... Sept-Oct............... 1,663 17 0.010 0.004
2016................................. Summer.................. Jul-Aug................ 1,914 74 0.039 0.017
Fall.................... Sept-Oct............... 2,360 19 0.008 0.004
2017................................. Summer.................. Jul-Aug................ 3,003 8 0.003 0.001
Fall.................... Sept-Oct............... 1,803 85 0.047 0.020
------------------------------------------------------------------------------------------------------------------
Total............................ Summer 10,993 141 \1\ 0.012 \1\ 0.005
Fall 11,047 259 \1\ 0.023 \1\ 0.0010
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Value represents average, not total, across all years per relevant season.
Gray Whales
Gray whales are rare in the project area and ASAMM aerial survey
block 1. From 2011 through 2017 only two gray whales have been observed
during ASAMM block 1 surveys despite over 21,000 miles of trackline
effort, for a resulting density of zero (Table 8). However, a group of
baleen whales comprised of both bowhead and gray whales was observed
during industry marine mammal surveys in Foggy Island Bay in 2008.
Therefore, Hilcorp has requested, and NMFS proposes to authorize, the
take, by Level B harassment, of two gray whales annually during the
effective period of the regulations on the chance gray whales enter the
ensonified zone during LDPI activities.
Table 8--Gray Whale Sighting Data From 2011 Through 2017 and Resulting Densities
--------------------------------------------------------------------------------------------------------------------------------------------------------
Transect Number whale
Year Season Month effort (km) sighted whale/km whale/km\2\
--------------------------------------------------------------------------------------------------------------------------------------------------------
2011................................. Summer.................. Jul-Aug................ 346 0 0.000 0.000
Fall.................... Sept-Oct............... 1,476 0 0.000 0.000
2012................................. Summer.................. Jul-Aug................ 1,493 0 0.000 0.000
Fall.................... Sept-Oct............... 1,086 0 0.000 0.000
2013................................. Summer.................. Jul-Aug................ 1,582 0 0.000 0.000
Fall.................... Sept-Oct............... 1,121 0 0.000 0.000
2014................................. Summer.................. Jul-Aug................ 1,393 0 0.000 0.000
Fall.................... Sept-Oct............... 1,538 1 0.001 0.000
2015................................. Summer.................. Jul-Aug................ 1,262 0 0.000 0.000
Fall.................... Sept-Oct............... 1,663 0 0.000 0.000
2016................................. Summer.................. Jul-Aug................ 1,914 1 0.001 0.000
Fall.................... Sept-Oct............... 2,360 0 0.000 0.000
2017................................. Summer.................. Jul-Aug................ 3,003 0 0.001 0.000
Fall.................... Sept-Oct............... 1,803 0 0.000 0.000
------------------------------------------------------------------------------------------------------------------
Total............................ Summer 10,993 1 0 0.000
Fall 11,047 1 0 0.000
--------------------------------------------------------------------------------------------------------------------------------------------------------
Beluga Whales
As with the large whales, beluga whale presence is anticipated to
be higher outside the barrier islands. Sighting data collected during
industry marine mammal surveys in Foggy Island Bay (as described in the
Description of Marine Mammals section) are used to estimate likelihood
of presence when deriving final take numbers; however, these data were
not collected in a manner that allows for a derivation of density
inside the bay or integration into the ASAMM survey data. The ASAMM
surveys were recently extended into Foggy Island Bay; however, no
beluga whales or any other cetaceans were observed while within the
Bay. Table 9 presents block 1 ASAMM survey data and resulting densities
for beluga whales. We note the 2012 and 2013 ASAMM reports stratified
beluga whale sightings by depth rather than by survey block. Because
the final beluga whale take numbers presented in this rule are adjusted
based on expected presence in the entire bay based on marine mammal
monitoring by industry in Foggy Island Bay, NMFS did not pursue
investigating the raw data further and believe the values here are a
reasonable and conservative representation of density in survey block 1
based on comparison to other ASAMM survey year sighting rates where
sightings by blocks are available.
[[Page 70310]]
Table 9--Beluga Whale Sighting Data From 2011 Through 2017 and Resulting Densities
--------------------------------------------------------------------------------------------------------------------------------------------------------
Transect Number whale
Year Season Month effort (km) sighted whale/km whale/km\2\
--------------------------------------------------------------------------------------------------------------------------------------------------------
2011................................. Summer.................. Jul-Aug................ 346 0 0.000 0.000
Fall.................... Sept-Oct............... 1,476 0 0.000 0.000
2012................................. Summer.................. Jul-Aug................ 5,001 47 0.009 0.008
Fall.................... Sept-Oct............... 4,868 5 0.001 0.001
2013................................. Summer.................. Jul-Aug................ 4,270 75 0.018 0.014
Fall.................... Sept-Oct............... 3,372 2 0.001 0.001
2014................................. Summer.................. Jul-Aug................ 1,393 13 0.009 0.008
Fall.................... Sept-Oct............... 1,538 9 0.006 0.005
2015................................. Summer.................. Jul-Aug................ 1,262 37 0.029 0.024
Fall.................... Sept-Oct............... 1,663 3 0.002 0.001
2016................................. Summer.................. Jul-Aug................ 1,914 \1\ 0 \1\ 0.00 \1\ 0.000
Fall.................... Sept-Oct............... 2,360 \1\ 1 \1\ 0.000 \1\ 0.000
2017................................. Summer.................. Jul-Aug................ 3,003 4 0.001 0.001
Fall.................... Sept-Oct............... 1,803 0 0.000 0.000
rrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrr
Total............................ Summer 17,189 521 0 \1\ 0.008
Fall 17,080 34 0 \1\ 0.001
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ The proposed rule contained an error in reporting the 2016 sighting data. Fewer whales were observed than reported, overestimating density. However,
the amount of beluga whale take authorized has not changed from the proposed rule because take numbers were increased from the calculated density
estimates.
Ringed Seals
Limited data are available on ringed seal densities in the southern
Beaufort Sea during the winter months; however, ringed seals winter
ecology studies conducted in the 1980s (Kelly et al., 1986, Frost and
Burns, 1989) and surveys associated with the Northstar development
(Williams et al., 2001) provide information on both seal ice-structure
use (where ice structures include both breathing holes and subnivean
lairs), and on the density of ice structures.
Kelly et al. (1986) found that in the southern Beaufort Sea and
Kotzebue Sound, radio-tagged seals used between 1 and at least 4
subnivean lairs. The distances between lairs was up to 4 km (10 mi),
with numerous breathing holes in-between (Kelly et al., 1986). While
Kelly et al. (1986) calculated the average number of lairs used per
seal to be 2.85, they also suggested that this was likely to be an
underestimate. To estimate winter ringed seal density within the
project area, sea-ice structure density surveyed in 1982 (3.6
structures/km\2\; Frost and Burns, 1982), 1983 (0.81 structures/km\2\;
Kelly et al., 1983), 1999 (0.71 structures/km\2\, Williams et al.,
2001), and 2000 (1.2 structures/km\2\, Williams et al., 2001) were
averaged to produce an average ice structure density of 1.58/km\2\.
That was divided by the average number of ice structures used by an
individual seal of 2.85 (SD = 2.51; Kelly et al., 1986), resulting in
an estimated density of 0.55 ringed seals/km\2\ during the winter
months. This density is likely to be overestimated due to Kelly et al.
(1986)'s suggestion that their estimate of the average number of lairs
used by a seal was an underestimate (the denominator used).
For spring ringed seal densities, aerial surveys flown in 1997
through 2002 over Foggy Island Bay and west of Prudhoe Bay during late
May and early June (Frost et al., 2002, Moulton et al., 2002b,
Richardson and Williams, 2003), when the greatest percentage of seals
have abandoned their lairs and are hauled out on the ice (Kelly et al.,
2010), provides the best available information on ringed seal
densities.
Because densities were consistently very low where water depth was
less than 3 m (and these areas are generally frozen solid during the
ice-covered season), densities have been calculated where water depth
was greater than 3 m deep (Moulton et al., 2002a, Moulton et al.,
2002b, Richardson and Williams, 2003). Based on the average density of
surveys flown between 1997 and 2002, the uncorrected average density of
ringed seals during the spring is expected to be 0.548 ringed seals/
km\2\. Because the number of seals is expected to be much lower during
the open-water season, we estimated summer (open-water) ringed seal
density to be 50 percent of the spring densities, resulting in an
estimated density of 0.27 ringed seals/km\2\. Ringed seals remain in
the water through the fall and in to the winter, however, due to the
lack of available data on fall densities within the LDPI action area we
have assumed the same density of ringed seals as in the summer; 0.27
ringed seals/km\2\ (see Hilcorp's application and NMFS (2018) for more
data details).
Bearded Seals
Industry monitoring surveys for the Northstar development during
the spring seasons in 1999 (Moulton et al., 2000), 2000 (Moulton et
al., 2001), 2001 (Moulton et al., 2002a), and 2002 (Moulton et al.,
2003) counted 47 bearded seals (annual mean of 11.75 seals during an
annual mean of 3,997.5 km\2\ of effort); these data were insufficient
to calculate a reliable density estimate in each year, no other data on
bearded seal presence were available. Annual reports (Richardson, 2008)
for years 2000 through 2002 include similar figures. A winter and
spring density using the four years of Northstar development data
equates to 0.003 bearded seals per km\2\.
For the open-water season (summer and fall), bearded seal density
was calculated as a proportion of the ringed seal summer density based
on the percentage of pinniped sightings during monitoring surveys in
1996 (Harris et al., 2001), 2008 (Aerts et al., 2008, Hauser et al.,
2008), and 2012 (HDR, 2012). During these surveys, 63 percent were
ringed seals, 17 percent were bearded seals, and 20 percent were
spotted seals. Thus, the density of bearded seals during the open-water
season (summer and fall) was calculated as 17 percent of the ringed
seal density of 0.27 seals/km\2\. This results in an estimated summer
density for bearded seals of 0.05 seals/km\2\.
Spotted Seals
Given their seasonal distribution and low numbers in the nearshore
waters of the central Alaskan Beaufort Sea, no spotted seals are
expected in the action
[[Page 70311]]
area during late winter and spring, but a few individuals could be
expected during the summer or fall. Using the same monitoring data
described in the bearded seal section above, spotted seal density
during the open-water season (summer and fall) was calculated as 20
percent of the ringed seal summer density estimate (0.27 seals/km\2\)
in the LDPI Project Area. This results in an estimated density of 0.05
seals/km\2\.
A summary of marine mammal densities used to estimate exposures is
provided, by season and species, in Table 10.
Table 10--Summary of Marine Mammal Densities
----------------------------------------------------------------------------------------------------------------
Winter (Nov- Spring (Apr- Summer (Jul- Fall (Sept-
Species Stock Mar) Jun) Aug) Oct)
----------------------------------------------------------------------------------------------------------------
Bowhead whale................. Western Arctic.. 0 0 0.005 0.01
Gray whale.................... Eastern N 0 0 0 0
Pacific.
Beluga whale.................. Beaufort Sea.... 0 0 0.008 0.001
Ringed seal................... Alaska.......... 0.548 0.548 0.27 0.27
Bearded seal.................. Alaska.......... 0.003 0.003 0.05 0.05
Spotted seal.................. Alaska.......... 0 0 0.05 0
----------------------------------------------------------------------------------------------------------------
Exposure Estimates
To quantitatively assess exposure of marine mammals to noise from
the various activities associated with the Liberty Project, Hilcorp
used the median range to which Level A harassment and Level B
harassment thresholds were reached for ice road construction and
maintenance, island construction, vibratory and impact sheet pile
driving, impact conductor pipe driving, slope shaping, drilling, and
production. Hilcorp considered the potential for takes on any given day
based on the largest Level B harassment zone for that day.
For each species, exposure estimates were calculated in a multi-
step process. On any given day of the year, the expected take for that
day per species was calculated as: density x ensonified area (of the
largest Level B harassment zone for that day). Results were then summed
for the year to provide total exposure estimates per species.
In some cases, however, the calculated densities alone do not
reflect the full potential of exposure. For example, beluga whale
densities are quite low; however, previous marine mammal surveys in
Foggy Island Bay have identified the potential for them to be there in
greater numbers than reflected based on NMFS survey data alone. In
other cases, the potential for exposure is almost discountable (e.g.,
calculated gray whale takes are zero) but given they could appear in
Foggy Island Bay, Hilcorp has requested take authorization. Hilcorp
also requested take authorization for bowhead whales despite the lack
of project-related noise above NMFS harassment thresholds extending
much beyond the McClure Islands (e.g., see Figure 02 in Appendix D of
Hilcorp's application), where bowheads are more likely to be found. As
described in the Marine Mammal Occurrence section, we used density
based on surveys conducted outside of the McClure Islands; therefore,
Hilcorp has likely overestimated potential takes. However, given the
sensitivities surrounding species in the Arctic, we believe a
precautionary approach is appropriate here to conservatively assess the
potential effects on the stock and subsistence use.
Bowhead, gray, and beluga whales have the potential to be present
and exposed to noise during the open-water season. Work during ice
conditions (e.g., pipeline installation, ice road construction) does
not have the potential to harass cetaceans because they are not present
in the action area. Hilcorp anticipates conducting a maximum of 15 days
of open-water pile driving and could conduct slope shaping throughout
the summer. The method described above was used to estimate take, by
Level B harassment, in year 1 when the LDPI would be constructed.
There is a very low potential for large whale Level A harassment
(PTS) from the specified activities given the rarity of bowhead and
gray whales entering Foggy Island Bay. However, in an abundance of
caution, Hilcorp has requested, and NMFS authorizes, limited Level A
harassment takes per year of each species potentially exposed to impact
pile driving noise (Table 11). Group size was considered in Level B
harassment take requests in cases where sighting data and group size
indicate potential for a greater amount of takes than calculated based
on density (e.g., beluga whale take request is higher than calculated
take estimate). A small amount of the Level B harassment exposures were
allocated to Level A harassment for the first year of work (i.e., pile
driving during open water).
For seals, a straight density estimate was used following the
method described above. In assessing the calculated results; there was
no need to adjust take numbers for Level B harassment.
The amount and manner of takes Hilcorp requested, and NMFS
authorizes, for each species is summarized in Table 11 below. There was
a slight adjustment to the number of Level B harassment takes for
bowhead whales and gray whales from the proposed to final rule to
account for an average group size of 2 and 5 animals, respectively,
should these species come within Foggy Island Bay. NMFS also slightly
adjusted ringed seal takes in years 2-5 as the calculations previously
presented by Hilcorp mistakenly omitted 15 days of work and used
drilling as the dominant noise source in the take equations in lieu of
ice road construction in December and January in years 4 and 5. These
changes resulted in an insignificant increase in the number of animals
potentially taken from the proposed rule (no more than 5 additional
takes in years 2-5). Given the very low density of bearded and spotted
seals in the area, no changes to the take estimate were necessary for
these species given this slight modification to the take calculations.
Therefore, all other takes remains the same as in the proposed rule. In
addition to the takes listed below, Hilcorp requests, and NMFS
authorizes, a total of two ringed seal mortalities over the life of the
regulations incidental to ice road construction, use, and maintenance.
[[Page 70312]]
Table 11--Annual and Total Amount of Takes, by Level A harassment and Level B harassment, Authorized Incidental to Hilcorp's LDPI Project
--------------------------------------------------------------------------------------------------------------------------------------------------------
Species (stock)
-------------------------------------------------------------------------------------
Year Bowhead (W Beluga Ringed seal Bearded seal Spotted seal
Arctic) Gray (ENP) (Beaufort) (AK) (AK) (AK)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Level A harassment
--------------------------------------------------------------------------------------------------------------------------------------------------------
1................................................................. 2 2 10 5 2 2
2................................................................. 0 0 0 0 0 0
3................................................................. 0 0 0 0 0 0
4................................................................. 0 0 0 0 0 0
5................................................................. 0 0 0 0 0 0
-------------------------------------------------------------------------------------
Total Level A harassment...................................... 2 2 10 5 2 2
--------------------------------------------------------------------------------------------------------------------------------------------------------
Level B harassment
--------------------------------------------------------------------------------------------------------------------------------------------------------
1................................................................. 6 2 40 336 58 58
2................................................................. 5 2 20 9 1 1
3................................................................. 5 2 20 23 1 1
4................................................................. 5 2 20 23 1 1
5................................................................. 5 2 20 20 1 1
-------------------------------------------------------------------------------------
Total Level B harassment...................................... 26 10 120 411 62 62
--------------------------------------------------------------------------------------------------------------------------------------------------------
Mitigation
In order to issue an ITA under Section 101(a)(5)(A) and (D) of the
MMPA, NMFS must set forth the permissible methods of taking pursuant to
such activity, and other means of effecting the least practicable
impact on such species or stock and its habitat, paying particular
attention to rookeries, mating grounds, and areas of similar
significance, and on the availability of such species or stock for
taking for certain subsistence uses.
NMFS regulations require applicants for incidental take
authorizations to include information about the availability and
feasibility (economic and technological) of equipment, methods, and
manner of conducting such activity or other means of effecting the
least practicable adverse impact upon the affected species or stocks
and their habitat (50 CFR 216.104(a)(11)).
In evaluating how mitigation may or may not be appropriate to
ensure the least practicable adverse impact on species or stocks and
their habitat, as well as subsistence uses where applicable, we
carefully consider two primary factors:
(1) The manner in which, and the degree to which, the successful
implementation of the measure(s) is expected to reduce impacts to
marine mammals, marine mammal species or stocks, and their habitat, as
well as subsistence uses. This considers the nature of the potential
adverse impact being mitigated (likelihood, scope, range). It further
considers the likelihood that the measure will be effective if
implemented (probability of accomplishing the mitigating result if
implemented as planned), and the likelihood of effective implementation
(probability implemented as planned), and;
(2) the practicability of the measures for applicant
implementation, which may consider such things as cost, impact on
operations, and, in the case of a military readiness activity,
personnel safety, practicality of implementation, and impact on the
effectiveness of the military readiness activity.
The mitigation measures presented here are a product of Hilcorp's
application, recommendations from the Arctic peer-review panel
(available at https://www.fisheries.noaa.gov/permit/incidental-take-
authorizations-under-marine-mammal-protection-act), NMFS'
recommendations, and public comments on the Federal Register Notice of
Receipt and the proposed rule.
Construction Mitigation Measures
Hilcorp will aim to construct the island, including the completion
of all pile driving, during the ice-covered season (as was done for
Northstar). Should an ice seal be observed on or near the LDPI by any
Hilcorp personnel, the sighting will be reported to Hilcorp's
Environmental Specialist. No construction activity should occur within
10 m of an ice seal and any vehicles used should use precaution and not
approach any ice seal within 10 m.
During the open-water season, the following mitigation measures
apply: Hilcorp will station two protected species observers (PSOs) on
elevated platforms on the island during all pile driving in open-water
conditions (see Monitoring and Reporting for more details). Marine
mammal monitoring shall take place from 30 minutes prior to initiation
of pile driving activity through 30 minutes post-completion of pile
driving activity. Pre-activity monitoring shall be conducted for 30
minutes to ensure that the shutdown zone is clear of marine mammals,
and pile driving may commence when observers have declared the shutdown
zone (which equates to the Level A harassment zone in Table 5) is clear
of marine mammals. In the event of a delay or shutdown of activity
resulting from marine mammals in the shutdown zone, animals shall be
allowed to remain in the shutdown zone (i.e., must leave of their own
volition) and their behavior shall be monitored and documented.
If a marine mammal is approaching a Level A harassment zone and
pile driving has not commenced, pile driving shall be delayed. Pile
driving may not commence or resume until either the animal has
voluntarily left and been visually confirmed beyond the shutdown zone;
15 minutes have passed without subsequent detections of small cetaceans
and pinnipeds; or 30 minutes have passed without subsequent detections
of large cetaceans. NMFS may adjust the shutdown zones pending review
and approval of an acoustic
[[Page 70313]]
monitoring report (see Monitoring and Reporting).
Hilcorp will use soft start techniques when impact pile driving.
Soft start requires contractors to provide an initial set of strikes at
reduced energy, followed by a thirty-second waiting period, then two
subsequent reduced energy strike sets. A soft start must be implemented
at the start of each day's impact pile driving and at any time
following cessation of impact pile driving for a period of thirty
minutes or longer.
In the unlikely event a low frequency cetacean (bowhead or gray
whale) approaches or enters the Level A harassment zone, pile driving
would be shut down. If a mid-frequency cetacean (beluga) or pinniped
(seal) enters the Level A harassment zone during pile driving, Hilcorp
proposes to complete setting the pile (which takes ten to fifteen
minutes from commencement) but will not initiate additional pile
driving of new piles until the marine mammal has left and is on a path
away from the Level A harassment zone. Hilcorp would not commence pile
driving if any species is observed approaching or within the Level A
harassment zone during the pre-construction monitoring period.
If a species for which authorization has not been granted, or a
species for which authorization has been granted but the authorized
takes are met, is observed approaching or within the monitoring zone
(which equates to the Level B harassment zone in Table 6), pile driving
and removal activities must shut down immediately using delay and shut-
down procedures. Activities must not resume until the animal has been
confirmed to have left the area or the observation time period, as
indicated above, has elapsed.
Hilcorp shall install the pipeline during the ice-covered season,
thereby minimizing noise impacts to marine mammals as noise does not
propagate well in ice and cetaceans are not present in the action area
during winter.
Mitigation for Ice Road Construction, Maintenance, and Use
During ice road construction, Hilcorp would follow several BMPs
recently developed through a collaborative effort with NMFS. These BMPs
are informed by the best available information on how ice roads are
constructed and maintained and ice seal lairing knowledge. They are
designed to minimize disturbance and set forth a monitoring and
reporting plan to improve knowledge. The complete BMP document is
available on our website at https://www.fisheries.noaa.gov/permit/
incidental-take-authorizations-under-marine-mammal-protection-act.
The ice road BMPs are applicable to construction and maintenance of
Liberty sea ice roads and sea ice trails in areas where water depth is
greater than 10 feet (ft) (the minimum depth required to establish
ringed seal lairs) as well as any open leads in the sea ice requiring a
temporary bridge during the ice road season. They are organized into
the following categories: (1) Wildlife training; (2) general BMPs
implemented throughout the ice road season; (3) BMPs to be implemented
prior to March 1st; (4) BMPs to be implemented after March 1; and (5)
reporting. We refer the reader to the complete BMP document on our
website but provide a summary of provisions here.
Timing--Hilcorp will construct sea ice roads as early as possible
(typically December 1 through mid-February) so that the entire corridor
is disturbed prior to March 1, the known onset of lairing season.
Blading and snow blowing of ice roads/trails will be limited to the
previously disturbed and delineated areas to the extent safe and
practicable. Snow will be plowed or blown from the ice surface so as to
preserve the safety and integrity of the ice surface for continued use.
After March 1, annually, blading and snow blowing of ice roads will
be limited to the previously disturbed ice road/shoulder areas to the
extent safe and practicable. However, when safety requires a new ice
trail to be constructed after March 1st, construction activities such
as drilling holes in the ice to determine ice quality and thickness,
will be conducted only during daylight hours with good visibility. All
identified ringed seal structures will be avoided by a minimum of 150 m
during ice road construction and maintenance.
Personnel--Hilcorp will employ a NMFS-approved, trained
environmental field specialist who will serve as the primary ice seal
monitor and main point of contact for any ice seal observations made by
other Hilcorp staff, employees, or contractors. This person shall be in
charge of conducting monitoring surveys every other day while the ice
road is being actively used. The specialist will also be responsible
for alerting all crew to ice seal sightings and reporting to the
appropriate officials.
Training--Prior to initiation of annual sea ice road activities,
all project personnel associated with ice road construction or use
(i.e., construction workers, surveyors, vehicle drivers security
personnel, and the environmental team) will receive annual training on
these BMPs. Annual training also includes reviewing the company's
Wildlife Interaction Plan, which has been modified to include reference
to the BMPs and reporting protocol. In addition to the BMPs, other
topics in the training may include ringed seal reproductive ecology
(e.g., temporal and spatial lairing behavior, habitat characteristics,
potential disturbance effect, etc.) and a summary of applicable laws
and regulatory requirements including, but not limited to, MMPA
incidental take authorization requirements.
General BMPs To Be Implemented Throughout Season--Hilcorp would
establish ice road speed limits, delineate the roadways with highly
visible markers (to avoid vehicles from driving off roadway where ice
seals may be more likely to lair), and clearly mark corners of rig
mats, steel plates, and other materials used to bridge sections of
hazardous ice (to allow for easy location of materials when removed,
minimizing disturbance to potentially nearby ice seals). Construction,
maintenance or decommissioning activities associated with ice roads and
trails will not occur within 50 m of any observed ring seal, but may
proceed as soon as the ringed seal, of its own accord, moves farther
than 50 m distance away from the activities or has not been observed
within that area for at least 24 hours. All personnel would be
prohibited from closely approaching any seal and would be required to
report all seals sighted within 50 m of the center of the ice road to
the designated Environmental Specialist.
Once the new ice trail is established, tracked vehicle operation
will be limited to the disturbed area to the extent practicable and
when the safety of personnel is ensured. If an ice road or trail is
being actively used under daylight conditions with good visibility, a
dedicated observer (not the vehicle operator) will conduct a survey
along the sea ice road/trail to observe if any ringed seals are within
150 m of the roadway corridor.
Mitigation for Subsistence Uses of Marine Mammals or Plan of
Cooperation
Regulations at 50 CFR 216.104(a)(12) further require incidental
take authorization (ITA) applicants conducting activities that take
place in Arctic waters to provide a Plan of Cooperation (POC) or
information that identifies what measures have been taken and/or will
be taken to minimize adverse effects on the availability of marine
mammals for subsistence purposes. A plan must include the following:
[[Page 70314]]
A statement that the applicant has notified and provided
the affected subsistence community with a draft plan of cooperation;
A schedule for meeting with the affected subsistence
communities to discuss proposed activities and to resolve potential
conflicts regarding any aspects of either the operation or the plan of
cooperation;
A description of what measures the applicant has taken
and/or will take to ensure that proposed activities will not interfere
with subsistence whaling or sealing; and
What plans the applicant has to continue to meet with the
affected communities, both prior to and while conducting the activity,
to resolve conflicts and to notify the communities of any changes in
the operation.
Hilcorp submitted a POC to NMFS, dated April 18, 2018, which
includes all the required elements included in the aforementioned
regulations (available at https://www.fisheries.noaa.gov/permit/
incidental-take-authorizations-under-marine-mammal-protection-act). The
POC documents Hilcorp's stakeholder engagement activities, which began
in 2014 for this project, with subsistence communities within the North
Slope Region including Nuiqsut, Barrow and Kaktovik, the closest
villages to the Project Area. The POC includes a description of the
project, how access to the Project Area will occur, pipeline and island
construction techniques, and drilling operations. The plan also
describes the ongoing community outreach cooperation and coordination
and measures that will be implemented by Hilcorp to minimize adverse
effects on marine mammal subsistence. The POC is a living document and
will be updated throughout the LDPI review and permitting process. As
such, Hilcorp intends to maintain open communication with all
stakeholders throughout the Liberty permitting and development process.
In addition, Hilcorp, along with several other North Slope Industry
participants, has entered into a Conflict Avoidance Agreement (CAA)
with the AEWC for all North Slope oil and gas activities to minimize
potential interference with bowhead subsistence hunting. By nature of
the measures, the mitigation described above also minimizes impacts to
subsistence users and is not repeated here. Additional mitigation
measures specific to subsistence use were included in the proposed
rule; however, we made minor modifications to better align with BOEM's
permit conditions. The proposed rule included the measure to avoid
impact pile and pipe driving during the Cross Island bowhead whale
hunt, which usually occurs from the last week of August through mid-
September. We have modified this measure to align with BOEM's
permitting measure, which requires Hilcorp to cease all pile- and pipe-
driving (both impact and vibratory) starting August 1, annually. This
restriction is in place until the official end of the hunt or until the
quota has been met, whichever occurs first.
We have also modified the measure included in the proposed rule
that stated Hilcorp must schedule all non-essential boat, hovercraft,
barge, and air traffic to avoid conflicting with the timing of the
Cross Island bowhead hunt. The new measure requires Hilcorp to avoid
operating LDPI-support vessels seaward of the barrier islands starting
August 1, annually, to better align with BOEM's permitting requirement.
This restriction is in place until the official end of the hunt or
until the quota has been met, whichever occurs first.
During the comment period on BOEM's EIS for this project and our
NOR announcing receipt of Hilcorp's application, the AEWC submitted
comments pertaining to potential effects on subsistence use. The AEWC
indicated that Hilcorp's continued participation in the Open Water
Season CAA and the Good Neighbor Policy (GNP), along with its
willingness to work with the Nuiqsut Whaling Captains to mitigate
subsistence harvest concerns, are central to the AEWC's support for the
Liberty Project. Further, the peer-review panel recommended the
existing POC and CAA should be renewed and implemented annually to
ensure that project activities are coordinated with the North Slope
Borough and Alaska Native whaling captains. Therefore, in addition to
the activity specific mitigation measures above, NMFS is requiring
Hilcorp to abide by the POC and remain committed to the GNP throughout
the life of the regulations. In addition, Hilcorp has committed to
following the CAA.
Based on our evaluation of the measures incorporated in this final
rule, NMFS has determined that the mitigation measures provide the
means of effecting the least practicable impact on the affected species
or stocks and their habitat, paying particular attention to rookeries,
mating grounds, and areas of similar significance, and on the
availability of such species or stock for subsistence uses.
Monitoring and Reporting
In order to issue an LOA for an activity, Section 101(a)(5)(A) of
the MMPA states that NMFS must set forth requirements pertaining to the
monitoring and reporting of the authorized taking. NMFS' MMPA
implementing regulations further describe the information that an
applicant should provide when requesting an authorization (50 CFR
216.104(a)(13)), including the means of accomplishing the necessary
monitoring and reporting that will result in increased knowledge of the
species and the level of taking or impacts on populations of marine
mammals.
Monitoring and reporting requirements prescribed by NMFS should
contribute to improved understanding of one or more of the following:
Occurrence of significant interactions with marine mammal
species in action area (e.g., animals that came close to the vessel,
contacted the gear, or are otherwise rare or displaying unusual
behavior);
Nature, scope, or context of likely marine mammal exposure
to potential stressors/impacts (individual or cumulative, acute or
chronic), through better understanding of: (1) Action or environment
(e.g., source characterization, propagation, ambient noise); (2)
affected species (e.g., life history, dive patterns); (3) co-occurrence
of marine mammal species with the action; or (4) biological or
behavioral context of exposure (e.g., age, calving or feeding areas);
Individual marine mammal responses (behavioral or
physiological) to acoustic stressors (acute, chronic, or cumulative),
other stressors, or cumulative impacts from multiple stressors;
How anticipated responses to stressors impact either: (1)
Long-term fitness and survival of individual marine mammals; or (2)
populations, species, or stocks;
Effects on marine mammal habitat (e.g., marine mammal prey
species, acoustic habitat, or important physical components of marine
mammal habitat); and
Mitigation and monitoring effectiveness.
Marine Mammal Monitoring During the Open-Water Season
Hilcorp shall employ NMFS approved PSOs and conduct marine mammal
monitoring per the Marine Mammal Monitoring Plan, dated February 12,
2019. Two PSOs will be placed on either side of the island where pile/
pipe-driving or slope shaping activities are occurring. For example,
one PSO would be placed on the side where construction activities are
taking place and the other placed on the opposite side to provide
complete observer
[[Page 70315]]
coverage around the island. PSO stations will be moved around the
island as needed during construction activities to provide full
coverage. PSOs will be switched out such that they will observe for no
more than 4 hours at a time and no more than 12 hours in a 24-hour
period.
A third island-based PSO will work closely with an aviation
specialist to monitor the Level B harassment zone during all open-water
pile and pipe driving using an unmanned aircraft system (UAS). This
third PSO and the UAS pilot will be located on the island. UAS
monitoring will also be used during slope shaping, which may occur in
open water intermittently until August 31 the first year the
regulations are valid. Should foundation piles be installed the
subsequent year, the requirement for UAS will be dependent upon the
success of the program in the previous year and results of any
preliminary acoustic analysis during year 1 construction (e.g., impact
driving conductor pipes). Should UAS not be deemed effective and
construction is ongoing during the open-water season, a vessel-based
PSO shall observe the monitoring zone during pile and pipe driving.
During the open-water season, marine mammal monitoring will take
place from 30 minutes prior to initiation of pile and pipe driving
activity through 30 minutes post-completion of pile driving activity.
Pile driving may commence when observers have declared the shutdown
zone clear of marine mammals. In the event of a delay or shutdown of
activity resulting from marine mammals in the shutdown zone, animals
must be allowed to remain in the shutdown zone (i.e., must leave of
their own volition) and their behavior must be monitored and
documented.
During the ice-covered season, in addition to ice road monitoring
(see below), Hilcorp personnel will report any ice seal sightings on or
near the LDPI to Hilcorp's Environmental Specialist.
Acoustic Monitoring During the Open-Water Season
Hilcorp will conduct acoustic monitoring of island construction
activities during the open-water season in accordance with its Acoustic
Monitoring Plan available on our website. In summary, Hilcorp proposes
to annually conduct underwater acoustic monitoring during the open-
water season (July through the beginning of October) using Directional
Autonomous Seafloor Acoustic Recorders (DASARs). One or more DASARs
will be deployed at a pre-determined GPS location(s) away from the
LDPI. Each DASAR will be connected by a ground line to an anchor on the
seafloor. At the end of the open water season, the DASAR will be
retrieved by dragging grappling hooks on the seafloor, perpendicular to
and over the location of the ground line, as defined by the GPS
locations of the anchor and DASAR. All activities conducted during the
open-water season will be monitored. Goals of the acoustic monitoring
plan are to characterize LDPI construction and operation noises,
ambient sound levels, and verify (or amend) modeled distances to NMFS
harassment thresholds. Recorder arrangement will be configured each
year based on the anticipated activities for that season and the
modelled sound propagation estimates for the relevant sources.
Hilcorp's acoustic monitoring plan can be found at https://www.fisheries.noaa.gov/permit/incidental-take-authorizations-under-
marine-mammal-protection-act.
Marine Mammal Monitoring During Ice Road Construction, Maintenance and
Use
Hilcorp has prepared a comprehensive ice seal monitoring and
mitigation plan via development of a BMP document which is available at
https://www.fisheries.noaa.gov/permit/incidental-take-authorizations-
under-marine-mammal-protection-act. Hilcorp would be required to
implement these BMPs; we provide a summary here but encourage the
public to review the full BMP document.
Seal surveys will be conducted every other day during daylight
hours. Observers for ice road activities need not be trained PSOs, but
they must have received the species observation training and understand
the applicable sections of Hilcorp's Wildlife Management Plan. In
addition, they must be capable of detecting, observing and monitoring
ringed seal presence and behaviors, and accurately and completely
recording data. Observers will have no other primary duty than to watch
for and report observations related to ringed seals during this survey.
If weather conditions become unsafe, the observer may be removed from
the monitoring activity.
Construction, maintenance or decommissioning activities associated
with ice roads and trails will not occur within 50 m of the observed
ring seal, but may proceed as soon as the ringed seal, of its own
accord, moves farther than 50 m distance away from the activities or
has not been observed within that area for at least 24 hours. Transport
vehicles (i.e., vehicles not associated with construction, maintenance
or decommissioning) may continue their route within the designated
road/trail without stopping.
If a ringed seal structure (i.e., breathing hole or lair) is
observed within 150 m of the ice road/trail, the location of the
structure will be reported to the Environmental Specialist who will
then carry out a notification protocol. A qualified observer will
monitor the structure every six hours on the day of the initial
sighting to determine whether a ringed seal is present. Monitoring for
the seal will occur every other day the ice road is being used unless
it is determined the structure is not actively being used (i.e., a seal
is not sighted at that location during monitoring).
Monitoring Plan Peer Review
The MMPA requires that monitoring plans be independently peer
reviewed where the proposed activity may affect the availability of a
species or stock for taking for subsistence uses (16 U.S.C.
1371(a)(5)(D)(ii)(III)). Regarding this requirement, NMFS' implementing
regulations state, upon receipt of a complete monitoring plan, and at
its discretion, NMFS will either submit the plan to members of a peer-
review panel for review or, within 60 days of receipt of the monitoring
plan, schedule a workshop to review the plan (50 CFR 216.108(d)).
NMFS established an independent peer review panel (PRP) to review
Hilcorp's 4MP for the proposed LDPI project in Foggy Island Bay. NMFS
provided the PRP with Hilcorp's ITA application and monitoring plan and
asked the panel to answer the following questions:
1. Will the applicant's stated objectives effectively further the
understanding of the impacts of their activities on marine mammals and
otherwise accomplish the goals stated above? If not, how should the
objectives be modified to better accomplish the goals above?
2. Can the applicant achieve the stated objectives based on the
methods described in the plan?
3. Are there technical modifications to the proposed monitoring
techniques and methodologies proposed by the applicant that should be
considered to better accomplish their stated objectives?
4. Are there techniques not proposed by the applicant (i.e.,
additional monitoring techniques or methodologies) that should be
considered for inclusion in the applicant's monitoring program to
better accomplish their stated objectives?
[[Page 70316]]
5. What is the best way for an applicant to present their data and
results (formatting, metrics, graphics, etc.) in the required reports
that are to be submitted to NMFS (i.e., 90-day report and comprehensive
report)?
The PRP met in May 2018 and subsequently provided a final report to
NMFS containing recommendations that the panel members felt were
applicable to Hilcorp's monitoring plans. The PRP concluded that the
objectives for both the visual and acoustic monitoring are appropriate,
and agrees that the objective of real-time mitigation of potential
disturbance of marine mammals would be met through visual monitoring.
The PRP's primary recommendations and comments are summarized and
addressed below. The PRP's full report is available on our website at
https://www.fisheries.noaa .gov/permit/incidental-take-authorizations-
under-marine-mammal-protection-act.
The PRP recommended Hilcorp consult with biologists at the NMFS
Marine Mammal Laboratory and other scientists and users familiar with
the use and limitations of UAS technology for studying marine mammals
at sea regarding appropriate protocols and procedures for the proposed
project. Hilcorp will implement a safe, effective UAS monitoring
program, as described in the Marine Mammal Monitoring Plan.
The PRP noted marine mammal monitoring would not be conducted
during the ice-covered season. Since the PRP met, Hilcorp has developed
a marine mammal monitoring plan that would be enacted during ice-
covered months along the ice roads and ice trails. These roads lead up
to the LDPI; therefore, marine mammal monitoring would occur during the
ice-covered season and occur at the LDPI. NMFS has also included a
provision requiring that any ice seals observed on or near the LDPI be
reported to Hilcorp's Environmental Specialist, and that no personnel
shall approach or operate equipment within 10 m of the seal.
The PRP was concerned that no acoustic monitoring would be
conducted during the winter months and recommended Hilcorp deploy
multiple acoustic recorders during ice-covered periods to obtain data
on both the presence of marine mammals and sound levels generated
during pile driving activities. Hilcorp is not deploying long-term
bottom mounted hydrophones, but will collect measurements using hand-
held hydrophones lowered in a hole drilled through the ice.
The PRP also encouraged Hilcorp to consider deployment of
additional acoustic recorders during the open-water season
approximately 15 km northwest of the project area to facilitate a
broader, multi-year approach to analyzing the effect of sound exposure
on marine mammals by various LDPI and non-LDPI sources. The deployment
of multiple recorders would provide a measure of redundancy and avoid
the risk of losing all of the season's data if the recorders are lost
or malfunction. Hilcorp will position multiple recorders simultaneously
to record sound levels at multiple ranges from the project activities.
Data recorded during times with no project activities, if such times
exist, will be analyzed for ambient sound level statistics. The
recorder arrangement will be configured each year based on the
anticipated activities for that season.
The PRP recommended that the existing POC and CAA be renewed and
implemented annually to ensure that project activities are coordinated
with the North Slope Borough and Alaska Native whaling captains.
Hilcorp is required to implement the POC and has agreed to implement a
CAA with the AEWC.
Reporting
General--Hilcorp will submit a draft report to NMFS within 90 days
of the completion of monitoring for each year the regulations are
valid. The report will include marine mammal observations pre-activity,
during-activity, and post-activity during pile driving days, and will
also provide descriptions of any behavioral responses to construction
activities by marine mammals, a complete description of all mitigation
shutdowns and the results of those actions, and an extrapolated total
take estimate based on the number of marine mammals observed during the
course of construction. A final report must be submitted within 30 days
following resolution of comments on the draft report. Hilcorp will also
submit a comprehensive annual summary report covering all activities
conducted under the incidental take regulations no more than 90 days
after the regulations expire.
Ice Road Reporting
On an annual basis, Hilcorp will also submit a draft report to NMFS
AKR and OPR compiling all ringed seal observations within 90 days of
decommissioning the ice road and ice trails. The report will include
information about activities occurring at time of sighting, ringed seal
age class and behavior, and actions taken to mitigate disturbance. In
addition, the report will include an analysis of the effectiveness of
the BMPs recently developed in coordination with NMFS and any proposed
updates to the BMPs or Wildlife Management Plan as a result of the
encounter. A final report shall be prepared and submitted within thirty
days following the resolution of comments on the draft report from
NMFS.
Hilcorp must submit more immediate reports to NMFS should a marine
mammal be unexpectedly killed or seriously injured by the specified
activity or a dead or injured marine mammal is observed by a PSO or
Hilcorp personnel. These are standard measures required by NMFS;
details on reporting timelines and information can be found in the
regulations.
LDPI Construction and Operation Reporting
Each day of marine mammal monitoring, PSOs will complete field
sheets containing information NMFS typically requires for pile driving
and construction activities. The full list of data is provided in
Hilcorp's Marine Mammal Monitoring and Mitigation Plan and in the
regulations below. Data include, but are not limited to, information on
daily activities occurring, marine mammal sighting information (e.g.,
species, group size, and behavior), manner and amount of take, and any
mitigation actions taken. Data in these field sheets will be summarized
and Hilcorp will provide a draft annual report to NMFS no later than 90
days post marine mammal monitoring efforts. Hilcorp would also submit
an annual acoustic monitoring report no later than 90 days after
acoustic recorders are recovered each season. The acoustic monitoring
reports shall contain measured dB rms, SEL, and peak values as well as
ambient noise levels, per the Acoustic Monitoring Plan and as described
below in the regulations.
Hilcorp will also submit to NMFS a draft final report on all marine
mammal monitoring conducted under the regulations no later than ninety
calendar days of the completion of marine mammal and acoustic
monitoring or sixty days prior to the issuance of any subsequent
regulations, if necessary, for this project, whichever comes first. A
final report shall be prepared and submitted within thirty days
following the resolution of comments on the draft report from NMFS.
[[Page 70317]]
Negligible Impact Analysis and Determination
Introduction
NMFS has defined negligible impact as an impact resulting from the
specified activity that cannot be reasonably expected to, and is not
reasonably likely to, adversely affect the species or stock through
effects on annual rates of recruitment or survival (50 CFR 216.103). A
negligible impact finding is based on the lack of likely adverse
effects on annual rates of recruitment or survival (i.e., population-
level effects). An estimate of the number of takes alone is not enough
information on which to base an impact determination. In addition to
considering estimates of the number of marine mammals that might be
``taken'' by mortality, serious injury, and Level A harassment or Level
B harassment, we consider other factors, such as the likely nature of
any behavioral responses (e.g., intensity, duration), the context of
any such responses (e.g., critical reproductive time or location,
migration), as well as effects on habitat, and the likely effectiveness
of mitigation. We also assess the number, intensity, and context of
estimated takes by evaluating this information relative to population
status. Consistent with the 1989 preamble for NMFS' implementing
regulations (54 FR 40338; September 29, 1989), the impacts from other
past and ongoing anthropogenic activities are incorporated into this
analysis via their impacts on the environmental baseline (e.g., as
reflected in the regulatory status of the species, population size and
growth rate where known, ongoing sources of human-caused mortality, and
specific consideration of take by M/SI previously authorized for other
NMFS research activities).
Serious Injury and Mortality
NMFS is proposing to authorize a very small number of serious
injuries or mortalities that could occur incidental to ice road
construction, use, and maintenance. We note here that the takes from
ice road construction, use, and maintenance enumerated below could
result in non-serious injury, but their worst potential outcome
(mortality) is analyzed for the purposes of the negligible impact
determination.
In addition, we discuss here the connection, and differences,
between the legal mechanisms for authorizing incidental take under
section 101(a)(5) for activities such as LDPI construction and
operation, and for authorizing incidental take from commercial
fisheries. In 1988, Congress amended the MMPA's provisions for
addressing incidental take of marine mammals in commercial fishing
operations. Congress directed NMFS to develop and recommend a new long-
term regime to govern such incidental taking (see MMC, 1994). The need
to develop a system suited to the unique circumstances of commercial
fishing operations led NMFS to suggest a new conceptual means and
associated regulatory framework. That concept, PBR, and a system for
developing plans containing regulatory and voluntary measures to reduce
incidental take for fisheries that exceed PBR were incorporated as
sections 117 and 118 in the 1994 amendments to the MMPA. In
Conservation Council for Hawaii v. National Marine Fisheries Service,
97 F. Supp.3d 1210 (D. Haw. 2015), which concerned a challenge to NMFS'
regulations and LOAs to the Navy for activities assessed in the 2013-
2018 Hawaii-Southern California Training and Testing (HSTT) MMPA
rulemaking, the Court ruled that NMFS' failure to consider PBR when
evaluating lethal takes in the negligible impact analysis under section
101(a)(5)(A) violated the requirement to use the best available
science.
PBR is defined in section 3 of the MMPA as the maximum number of
animals, not including natural mortalities, that may be removed from a
marine mammal stock while allowing that stock to reach or maintain its
optimum sustainable population (OSP) and, although not controlling, can
be one measure considered among other factors when evaluating the
effects of M/SI on a marine mammal species or stock during the section
101(a)(5)(A) process. OSP is defined in section 3 of the MMPA as the
number of animals which will result in the maximum productivity of the
population or the species, keeping in mind the carrying capacity of the
habitat and the health of the ecosystem of which they form a
constituent element. Through section 2, an overarching goal of the
statute is to ensure that each species or stock of marine mammal is
maintained at or returned to its OSP.
PBR values are calculated by NMFS as the level of annual removal
from a stock that will allow that stock to equilibrate within OSP at
least 95 percent of the time, and is the product of factors relating to
the minimum population estimate of the stock (Nmin), the
productivity rate of the stock at a small population size, and a
recovery factor. Determination of appropriate values for these three
elements incorporates significant precaution, such that application of
the parameter to the management of marine mammal stocks may be
reasonably certain to achieve the goals of the MMPA. For example,
calculation of the minimum population estimate (Nmin)
incorporates the level of precision and degree of variability
associated with abundance information, while also providing reasonable
assurance that the stock size is equal to or greater than the estimate
(Barlow et al., 1995), typically by using the 20th percentile of a log-
normal distribution of the population estimate. In general, the three
factors are developed on a stock-specific basis in consideration of one
another in order to produce conservative PBR values that appropriately
account for both imprecision that may be estimated, as well as
potential bias stemming from lack of knowledge (Wade, 1998).
Congress called for PBR to be applied within the management
framework for commercial fishing incidental take under section 118 of
the MMPA. As a result, PBR cannot be applied appropriately outside of
the section 118 regulatory framework without consideration of how it
applies within the section 118 framework, as well as how the other
statutory management frameworks in the MMPA differ from the framework
in section 118. PBR was not designed and is not used as an absolute
threshold limiting commercial fisheries. Rather, it serves as a means
to evaluate the relative impacts of those activities on marine mammal
stocks. Even where commercial fishing is causing M/SI at levels that
exceed PBR, the fishery is not suspended. When M/SI exceeds PBR in the
commercial fishing context under section 118, NMFS may develop a take
reduction plan, usually with the assistance of a take reduction team.
The take reduction plan will include measures to reduce and/or minimize
the taking of marine mammals by commercial fisheries to a level below
the stock's PBR. That is, where the total annual human-caused M/SI
exceeds PBR, NMFS is not required to halt fishing activities
contributing to total M/SI but rather utilizes the take reduction
process to further mitigate the effects of fishery activities via
additional bycatch reduction measures. In other words, under section
118 of the MMPA, PBR does not serve as a strict cap on the operation of
commercial fisheries that may incidentally take marine mammals.
Similarly, to the extent PBR may be relevant when considering the
impacts of incidental take from activities other than commercial
fisheries, using it as the sole reason to deny (or issue) incidental
take authorization for those activities would be inconsistent with
Congress's intent under section
[[Page 70318]]
101(a)(5), NMFS' long-standing regulatory definition of ``negligible
impact,'' and the use of PBR under section 118. The standard for
authorizing incidental take for activities other than commercial
fisheries under section 101(a)(5) continues to be, among other things
that are not related to PBR, whether the total taking will have a
negligible impact on the species or stock. Nowhere does section
101(a)(5)(A) reference use of PBR to make the negligible impact finding
or authorize incidental take through multi-year regulations, nor does
its companion provision at 101(a)(5)(D) for authorizing non-lethal
incidental take under the same negligible-impact standard. NMFS' MMPA
implementing regulations state that take has a negligible impact when
it does not ``adversely affect the species or stock through effects on
annual rates of recruitment or survival''--likewise without reference
to PBR. When Congress amended the MMPA in 1994 to add section 118 for
commercial fishing, it did not alter the standards for authorizing non-
commercial fishing incidental take under section 101(a)(5), implicitly
acknowledging that the negligible impact standard under section
101(a)(5) is separate from the PBR metric under section 118. In fact,
in 1994 Congress also amended section 101(a)(5)(E) (a separate
provision governing commercial fishing incidental take for species
listed under the ESA) to add compliance with the new section 118 but
retained the standard of the negligible impact finding under section
101(a)(5)(A) (and section 101(a)(5)(D)), showing that Congress
understood that the determination of negligible impact and application
of PBR may share certain features but are, in fact, different.
Since the introduction of PBR in 1994, NMFS had used the concept
almost entirely within the context of implementing sections 117 and 118
and other commercial fisheries management-related provisions of the
MMPA. Prior to the Court's ruling in Conservation Council for Hawaii v.
National Marine Fisheries Service and consideration of PBR in a series
of section 101(a)(5) rulemakings, there were a few examples where PBR
had informed agency deliberations under other MMPA sections and
programs, such as playing a role in the issuance of a few scientific
research permits and subsistence takings. But as the Court found when
reviewing examples of past PBR consideration in Georgia Aquarium v.
Pritzker, 135 F. Supp. 3d 1280 (N.D. Ga. 2015), where NMFS had
considered PBR outside the commercial fisheries context, ``it has
treated PBR as only one `quantitative tool' and [has not used it] as
the sole basis for its impact analyses.'' Further, the agency's
thoughts regarding the appropriate role of PBR in relation to MMPA
programs outside the commercial fishing context have evolved since the
agency's early application of PBR to section 101(a)(5) decisions.
Specifically, NMFS' denial of a request for incidental take
authorization for the U.S. Coast Guard in 1996 seemingly was based on
the potential for lethal take in relation to PBR and did not appear to
consider other factors that might also have informed the potential for
ship strike in relation to negligible impact (61 FR 54157; October 17,
1996).
The MMPA requires that PBR be estimated in SARs and that it be used
in applications related to the management of take incidental to
commercial fisheries (i.e., the take reduction planning process
described in section 118 of the MMPA and the determination of whether a
stock is ``strategic'' as defined in section 3), but nothing in the
statute requires the application of PBR outside the management of
commercial fisheries interactions with marine mammals. Nonetheless,
NMFS recognizes that as a quantitative metric, PBR may be useful as a
consideration when evaluating the impacts of other human-caused
activities on marine mammal stocks. Outside the commercial fishing
context, and in consideration of all known human-caused mortality, PBR
can help inform the potential effects of M/SI requested to be
authorized under 101(a)(5)(A). As noted by NMFS and the U.S. Fish and
Wildlife Service in our implementation regulations for the 1986
amendments to the MMPA (54 FR 40341, September 29, 1989), the Services
consider many factors, when available, in making a negligible impact
determination, including, but not limited to, the status of the species
or stock relative to OSP (if known); whether the recruitment rate for
the species or stock is increasing, decreasing, stable, or unknown; the
size and distribution of the population; and existing impacts and
environmental conditions. In this multi-factor analysis, PBR can be a
useful indicator for when, and to what extent, the agency should take
an especially close look at the circumstances associated with the
potential mortality, along with any other factors that could influence
annual rates of recruitment or survival.
When considering PBR during evaluation of effects of M/SI under
section 101(a)(5)(A), we first calculate a metric for each species or
stock that incorporates information regarding ongoing anthropogenic M/
SI from all sources into the PBR value (i.e., PBR minus the total
annual anthropogenic mortality/serious injury estimate in the SAR),
which is called ``residual PBR.'' (Wood et al., 2012). We first focus
our analysis on residual PBR because it incorporates anthropogenic
mortality occurring from other sources. If the ongoing human-caused
mortality from other sources does not exceed PBR, then residual PBR is
a positive number, and we consider how the anticipated or potential
incidental M/SI from the activities being evaluated compares to
residual PBR using the framework in the following paragraph. If the
ongoing anthropogenic mortality from other sources already exceeds PBR,
then residual PBR is a negative number and we consider the M/SI from
the activities being evaluated as described further below.
When ongoing total anthropogenic mortality from the applicant's
specified activities does not exceed PBR and residual PBR is a positive
number, as a simplifying analytical tool we first consider whether the
specified activities could cause incidental M/SI that is less than 10
percent of residual PBR (the ``insignificance threshold,'' see below).
If so, we consider M/SI from the specified activities to represent an
insignificant incremental increase in ongoing anthropogenic M/SI for
the marine mammal stock in question that alone (i.e., in the absence of
any other take) will not adversely affect annual rates of recruitment
and survival. As such, this amount of M/SI would not be expected to
affect rates of recruitment or survival in a manner resulting in more
than a negligible impact on the affected stock unless there are other
factors that could affect reproduction or survival, such as Level A
and/or Level B harassment, or other considerations such as information
that illustrates the uncertainty involved in the calculation of PBR for
some stocks. In a few prior incidental take rulemakings, this threshold
was identified as the ``significance threshold,'' but it is more
accurately labeled an insignificance threshold, and so we use that
terminology here, as we did in the Atlantic Fleet Training and Testing
(AFTT) Proposed (83 FR 10954; March 13, 2017) and Final Rules (83 FR
57076; November 14, 2018). Assuming that any additional incidental take
by Level A or Level B harassment from the activities in question would
not combine with the effects of the authorized M/SI to exceed the
negligible impact level, the anticipated M/SI caused by the
[[Page 70319]]
activities being evaluated would have a negligible impact on the
species or stock. However, M/SI above the 10 percent insignificance
threshold does not indicate that the M/SI associated with the specified
activities is approaching a level that would necessarily exceed
negligible impact. Rather, the 10 percent insignificance threshold is
meant only to identify instances where additional analysis of the
anticipated M/SI is not required because the negligible impact standard
clearly will not be exceeded on that basis alone.
Where the anticipated M/SI is near, at, or above residual PBR,
consideration of other factors (positive or negative), including those
outlined above, as well as mitigation is especially important to
assessing whether the M/SI will have a negligible impact on the species
or stock. PBR is a conservative metric and not sufficiently precise to
serve as an absolute predictor of population effects upon which
mortality caps would appropriately be based. For example, in some cases
stock abundance (which is one of three key inputs into the PBR
calculation) is underestimated because marine mammal survey data within
the U.S. Exclusive Economic Zone (EEZ) are used to calculate the
abundance even when the stock range extends well beyond the U.S. EEZ.
An underestimate of abundance could result in an underestimate of PBR.
Alternatively, we sometimes may not have complete M/SI data beyond the
U.S. EEZ to compare to PBR, which could result in an overestimate of
residual PBR. The accuracy and certainty around the data that feed any
PBR calculation, such as the abundance estimates, must be carefully
considered to evaluate whether the calculated PBR accurately reflects
the circumstances of the particular stock. M/SI that exceeds PBR may
still potentially be found to be negligible in light of other factors
that offset concern, especially when robust mitigation and adaptive
management provisions are included.
In Conservation Council for Hawaii v. National Marine Fisheries
Service, which involved the challenge to NMFS' issuance of LOAs to the
Navy in 2013 for activities in the HSTT Study Area, the Court reached a
different conclusion, stating, ``Because any mortality level that
exceeds PBR will not allow the stock to reach or maintain its OSP, such
a mortality level could not be said to have only a `negligible impact'
on the stock.'' As described above, the Court's statement fundamentally
misunderstands the two terms and incorrectly indicates that these
concepts (PBR and ``negligible impact'') are directly connected, when
in fact nowhere in the MMPA is it indicated that these two terms are
equivalent.
Specifically, PBR was designed as a tool for evaluating mortality
and is defined as the number of animals that can be removed while
``allowing that stock to reach or maintain its OSP.'' OSP is defined as
a population that falls within a range from the population level that
is the largest supportable within the ecosystem to the population level
that results in maximum net productivity, and thus is an aspirational
management goal of the overall statute with no specific timeframe by
which it should be met. PBR is designed to ensure minimal deviation
from this overarching goal, with the formula for PBR typically ensuring
that growth towards OSP is not reduced by more than 10 percent (or
equilibrates to OSP 95 percent of the time). As PBR is applied by NMFS,
it provides that growth toward OSP is not reduced by more than 10
percent, which certainly allows a stock to ``reach or maintain its
OSP'' in a conservative and precautionary manner--and we can therefore
clearly conclude that if PBR were not exceeded, there would not be
adverse effects on the affected species or stocks. Nonetheless, it is
equally clear that in some cases the time to reach this aspirational
OSP level could be slowed by more than 10 percent (i.e., total human-
caused mortality in excess of PBR could be allowed) without adversely
affecting a species or stock through effects on its rates of
recruitment or survival. Thus even in situations where the inputs to
calculate PBR are thought to accurately represent factors such as the
species' or stock's abundance or productivity rate, it is still
possible for incidental take to have a negligible impact on the species
or stock even where M/SI exceeds residual PBR or PBR.
As noted above, PBR is helpful in informing the analysis of the
effects of mortality on a species or stock because it is important from
a biological perspective to be able to consider how the total mortality
in a given year may affect the population. However, section
101(a)(5)(A) of the MMPA indicates that NMFS shall authorize the
requested incidental take from a specified activity if we find that the
total of such taking i.e., from the specified activity will have a
negligible impact on such species or stock. In other words, the task
under the statute is to evaluate the applicant's anticipated take in
relation to their take's impact on the species or stock, not other
entities' impacts on the species or stock. Neither the MMPA nor NMFS'
implementing regulations call for consideration of other unrelated
activities and their impacts on the species or stock. In fact, in
response to public comments on the implementing regulations NMFS
explained that such effects are not considered in making negligible
impact findings under section 101(a)(5), although the extent to which a
species or stock is being impacted by other anthropogenic activities is
not ignored. Such effects are reflected in the baseline of existing
impacts as reflected in the species' or stock's abundance,
distribution, reproductive rate, and other biological indicators.
NMFS guidance for commercial fisheries provides insight when
evaluating the effects of an applicant's incidental take as compared to
the incidental take caused by other entities. Parallel to section
101(a)(5)(A), section 101(a)(5)(E) of the MMPA provides that NMFS shall
allow the incidental take of ESA-listed endangered or threatened marine
mammals by commercial fisheries if, among other things, the incidental
M/SI from the commercial fisheries will have a negligible impact on the
species or stock. As discussed earlier, the authorization of incidental
take resulting from commercial fisheries and authorization for
activities other than commercial fisheries are under two separate
regulatory frameworks. However when it amended the statute in 1994 to
provide a separate incidental take authorization process for commercial
fisheries, Congress kept the requirement of a negligible impact
determination for this one category of species, thereby applying the
standard to both programs. Therefore, while the structure and other
standards of the two programs differ such that evaluation of negligible
impact under one program may not be fully applicable to the other
program (e.g., the regulatory definition of ``negligible impact'' at 50
CFR 216.103 applies only to activities other than commercial fishing),
guidance on determining negligible impact for commercial fishing take
authorizations can be informative when considering incidental take
outside the commercial fishing context. In 1999, NMFS published
criteria for making a negligible impact determination pursuant to
section 101(a)(5)(E) of the MMPA in a notice of proposed permits for
certain fisheries (64 FR 28800; May 27, 1999). Criterion 2 stated ``If
total human-related serious injuries and mortalities are greater than
PBR, and fisheries-related mortality is less than 0.1 PBR, individual
fisheries may be permitted if management measures are being taken to
address non-fisheries-related serious injuries and mortalities.
[[Page 70320]]
When fisheries-related serious injury and mortality is less than 10
percent of the total, the appropriate management action is to address
components that account for the major portion of the total.'' This
criterion addresses when total human-caused mortality is exceeding PBR,
but the activity being assessed is responsible for only a small portion
of the mortality. In incidental take authorizations in which NMFS has
recently articulated a fuller description of how we consider PBR under
section 101(a)(5)(A), this situation had not arisen, and NMFS'
description of how we consider PBR in the section 101(a)(5)
authorization process did not, therefore, include consideration of this
scenario. However, the analytical framework we use here appropriately
incorporates elements of the one developed for use under section
101(a)(5)(E) and because the negligible impact determination under
section 101(a)(5)(A) focuses on the activity being evaluated, it is
appropriate to utilize the parallel concept from the framework for
section 101(a)(5)(E).
Accordingly, we are using a similar criterion in our negligible
impact analysis under section 101(a)(5)(A) to evaluate the relative
role of an applicant's incidental take when other sources of take are
causing PBR to be exceeded, but the take of the specified activity is
comparatively small. Where this occurs, we may find that the impacts of
the taking from the specified activity may (alone) be negligible even
when total human-caused mortality from all activities exceeds PBR if
(in the context of a particular species or stock): the authorized
mortality or serious injury would be less than or equal to 10 percent
of PBR and management measures are being taken to address serious
injuries and mortalities from the other activities (i.e., other than
the specified activities covered by the incidental take authorization
under consideration). We must also determine, though, that impacts on
the species or stock from other types of take (i.e., harassment) caused
by the applicant do not combine with the impacts from mortality or
serious injury to result in adverse effects on the species or stock
through effects on annual rates of recruitment or survival.
As discussed above, however, while PBR is useful in informing the
evaluation of the effects of M/SI in section 101(a)(5)(A)
determinations, it is just one consideration to be assessed in
combination with other factors and is not determinative, including
because, as explained above, the accuracy and certainty of the data
used to calculate PBR for the species or stock must be considered. And
we reiterate the considerations discussed above for why it is not
appropriate to consider PBR an absolute cap in the application of this
guidance. Accordingly, we use PBR as a trigger for concern while also
considering other relevant factors to provide a reasonable and
appropriate means of evaluating the effects of potential mortality on
rates of recruitment and survival, while acknowledging that it is
possible to exceed PBR (or exceed 10 percent of PBR in the case where
other human-caused mortality is exceeding PBR but the specified
activity being evaluated is an incremental contributor, as described in
the last paragraph) by some small amount and still make a negligible
impact determination under section 101(a)(5)(A).
Regarding the impacts of the specified activities analyzed here, a
stock-wide PBR for ringed seals is unknown; however, Muto et al. (2018)
estimate that PBR for ringed seals in the Bering Sea alone is 5,100
seals. Total annual mortality and serious injury is 1,054 for an r-PBR
of 4,046, which means that the 10 percent insignificance threshold is
405 seals. No mortality or serious injury of ringed seals is currently
authorized under any other incidental take authorization issued
pursuant to section 101(a)(5)(A) of the MMPA. In the case of the LDPI,
the authorized taking, by mortality, of two ringed seals over the
course of 5 years, which equates to 0.4 mortality takes annually, is
less than 10 percent r-PBR when considering mortality and serious
injury caused by other anthropogenic sources. This takings amount, by
mortality and serious injury, is considered insignificant and therefore
supports our negligible impact finding.
Harassment
Hilcorp requests, and NMFS authorizes takes, by Level A harassment
and Level B harassment, of six species of marine mammals. The amount of
taking analyzed, and which may be authorized pursuant to these
regulations, is low compared to marine mammal abundance. Potential
impacts of LDPI activities include PTS, TTS, and behavioral changes due
to exposure to construction and operation noise. The potential for
Level A harassment occurs during impact pile driving. As discussed in
the Potential Effects of the Specified Activity on Marine Mammals and
Their Habitat section, PTS is a permanent shift in hearing threshold
and the severity of the shift is determined by a myriad of factors.
Here, we expect cetaceans to incur only a slightly elevated shift in
hearing threshold because we do not expect them to be close to the
source (especially large whales who primarily stay outside the McClure
Island group) and impact pile driving (the source with the greatest
potential to cause PTS) would only occur for a maximum of 40 minutes
per day. Therefore, the potential for large threshold shifts is
unlikely. Further, the frequency range of hearing that may be impaired
is limited to the frequency bands of the source. Pile driving exhibits
energy in lower frequencies. While low-frequency baleen whales are most
susceptible to such bands, these are the species that are unlikely to
come very close to the source. Mid-frequency cetaceans and phocids do
not hear best within these lower frequency bands; therefore, the
resulting impact of any threshold shift is less likely to impair vital
hearing. All other noise generated from the project is expected to be
low level from activities such as slope-shaping and drilling and not
result in PTS.
Cetaceans are infrequent visitors to Foggy Island Bay with their
primary habitat lying outside the McClure Islands. Any taking within
Foggy Island Bay is not expected to impact reproductive or survival
activities as the bay is not known to contain such critical areas as
rookeries, mating grounds, or other areas of similar significance. Some
ringed seals do lair in Foggy Island Bay; however, the area impacted by
the project is small compared to available habitat. Further, to offset
impacts to reproductive behaviors by ringed seals (e.g., lairing,
pupping), Hilcorp would follow a number of ice road BMPs developed in
coordination with NMFS ringed seal experts. Hilcorp would also not
impact pile drive during the bowhead whale hunt, thereby minimizing
impacts to whales during peak migration periods (we note the peak
migratory pathway for bowhead whales is well outside the McClure
Islands). Finally, for reasons described above, the taking of two
ringed seals, by mortality, over the course of 5 years is not expected
to have impacts on the species' rates of recruitment and survival.
In summary and as described above, the following factors primarily
support our preliminary determination that the impacts resulting from
this activity are not expected to adversely affect the species or stock
through effects on annual rates of recruitment or survival:
Only two ringed seals are authorized to be taken by
mortality over 5 years;
Any PTS would be of a small degree;
[[Page 70321]]
The amount of takes, by harassment, is low compared to
population sizes;
The area ensonified by Hilcorp's activities does not occur
in any known important areas for marine mammals and is a de minimis
subset of habitat used by and available to marine mammals;
Impacts to critical behaviors such as lairing and pupping
by ringed seals would be avoided and minimized through implementation
of ice road BMPs; and
Hilcorp would avoid noise-generating activities during the
bowhead whale hunt; thereby minimizing impact to critical behavior
(i.e., migration).
Based on the analysis contained herein of the likely effects of the
specified activity on marine mammals and their habitat, and taking into
consideration the implementation of the monitoring and mitigation
measures, NMFS finds that the total marine mammal taking from the
proposed activity will have a negligible impact on all affected marine
mammal species or stocks.
Small Numbers
As noted above, only small numbers of incidental takes may be
authorized under Section 101(a)(5)(A) of the MMPA for specified
activities. The MMPA does not define small numbers and so, in practice,
where estimated numbers are available NMFS compares the number of
individuals taken to the most appropriate estimation of abundance of
the relevant species or stock in our determination of whether an
authorization is limited to small numbers of marine mammals.
Additionally, other qualitative factors may be considered in the
analysis, such as the temporal or spatial scale of the activities.
The amount of total taking (i.e., Level A harassment, Level B
harassment, and, for ringed seals, mortality) of any marine mammal
stock over the course of 5 years, is less than one percent of any
population (Table 12).
Table 12--Amount of Taking, by Species, Authorized Relative to Population Estimates (Nbest)
----------------------------------------------------------------------------------------------------------------
Population Percent of
Species Stock estimate Total taking population
----------------------------------------------------------------------------------------------------------------
Bowhead whale...................... Arctic..................... 16,820 28 <1
Gray whale......................... ENP........................ 20,990 12 <1
Beluga whale....................... Beaufort Sea............... 39,258 130 <1
Ringed seal........................ Alaska..................... 170,000 416 <1
Bearded seal....................... Alaska..................... 299,174 64 <1
Spotted seal....................... Alaska..................... 423,625 64 <1
----------------------------------------------------------------------------------------------------------------
Based on the analysis contained herein of the proposed activity
(including the mitigation and monitoring measures) and the anticipated
taking of marine mammals, NMFS finds that small numbers of marine
mammals will be taken relative to the population sizes of the affected
species or stocks.
Impact on Availability of Affected Species for Taking for Subsistence
Uses
As described in the Marine Mammal section of the document, all
species potentially taken by Hilcorp's specified activities are key
subsistence species, in particular the bowhead whales and ice seals.
Hilcorp has proposed and NMFS has included several mitigation measures
to address potential impacts on the availability of marine mammals for
subsistence use. The AEWC expressed support for Hilcorp's efforts to
reduce impacts to subsistence use and offered no objection to the final
rule. Hilcorp is required to abide by the POC. In addition, mitigation
measures designed to minimize impacts on marine mammals also minimize
impacts to subsistence users (e.g., avoid impact pile driving during
the fall bowhead whale hunt). Hilcorp and NMFS have also developed a
comprehensive set of BMPs to minimize impacts to ice seals during ice-
covered months. Considering the coordination with the AEWC, Hilcorp's
proposed work schedule (i.e., conducting the majority of work in winter
when bowhead whales are not present), and the incorporation of several
mitigation measures, we have determined that the total taking of
affected species or stocks would not have an unmitigable adverse impact
on the availability of such species or stocks for taking for
subsistence purposes.
Adaptive Management
The regulations governing the taking of marine mammals incidental
to Hilcorp's LPDI construction and operational activities would contain
an adaptive management component.
The reporting requirements associated with this rule are designed
to provide NMFS with monitoring data from the previous year to allow
consideration of whether any changes are appropriate. The use of
adaptive management allows NMFS to consider new information from
different sources to determine (with input from Hilcorp regarding
practicability) on an annual or biennial basis if mitigation or
monitoring measures should be modified (including additions or
deletions). Mitigation measures could be modified if new data suggests
that such modifications would have a reasonable likelihood of reducing
adverse effects to marine mammals and if the measures are practicable.
The following are some of the possible sources of applicable data
to be considered through the adaptive management process: (1) Results
from monitoring reports, as required by MMPA authorizations; (2)
results from general marine mammal and sound research; and (3) any
information which reveals that marine mammals may have been taken in a
manner, extent, or number not authorized by these regulations or
subsequent LOAs. In addition, results of the annual peer-review panel,
of which Hilcorp has agreed to participate, may warrant modifications
through the adaptive management process.
National Environmental Policy Act
To comply with the National Environmental Policy Act of 1969 (NEPA;
42 U.S.C. 4321 et seq.) and NOAA Administrative Order (NAO) 216-6A,
NMFS must evaluate our proposed action (i.e., the promulgation of
regulations and subsequent issuance of incidental take authorization)
and alternatives with respect to potential impacts on the human
environment.
On August 23, 2018, the Bureau of Ocean Energy Management (BOEM)
released a Final Environmental Impact Statement (EIS) analyzing the
possible environmental impacts of Hilcorp's proposed Liberty
development and production plan (DPP). BOEM's Draft EIS was made
available for public comment from August 18, 2017 through December 8,
2017. The final EIS may be found at https://www.boem.gov/hilcorp-
[[Page 70322]]
liberty/. NMFS is a cooperating agency on the EIS. NMFS has conducted
an independent evaluation of the EIS, including consideration of public
comments on the proposed rule, and found that the EIS includes adequate
information analyzing the effects on the human environment of issuing
this final rule. Therefore, NMFS has adopted the EIS and signed a
Record of Decision documenting NMFS' finding. All NEPA documents are
available on the project's website at https://www.fisheries.noaa.gov/
permit/incidental-take-authorizations-under-marine-mammal-protection-
act.
Endangered Species Act (ESA)
Section 7(a)(2) of the Endangered Species Act of 1973 (ESA: 16
U.S.C. 1531 et seq.) requires that each Federal agency insure that any
action it authorizes, funds, or carries out is not likely to jeopardize
the continued existence of any endangered or threatened species or
result in the destruction or adverse modification of designated
critical habitat. To ensure ESA compliance for the issuance of ITAs,
NMFS consults internally, in this case with the Alaska Regional Office,
whenever we propose to authorize take for endangered or threatened
species. Specific to the LDPI, the bowhead whale, ringed seal, and
bearded seal (Beringia DPS) are listed under the ESA (see Table 2).
The Permit and Conservation Division requested initiation of
Section 7 consultation with the Alaska Regional Office on the
promulgation of five-year regulations and the subsequent issuance of
LOAs to Hilcorp under section 101(a)(5)(A) of the MMPA. On August 30,
2019, NMFS Alaska Region (AKR) issued a Biological Opinion on the
Liberty Oil and Gas Development and Production Plan Activities,
Beaufort Sea, Alaska to NMFS OPR concluding the promulgation of
regulations and subsequent issuance of the LOA would not jeopardize the
continued existence of any endangered or threatened species or destroy
or adversely modify any designated critical habitat.
Classification
Pursuant to the procedures established to implement Executive Order
12866, the Office of Management and Budget has determined that this
final rule is not significant.
Pursuant to section 605(b) of the Regulatory Flexibility Act (RFA),
the Chief Counsel for Regulation of the Department of Commerce has
certified to the Chief Counsel for Advocacy of the Small Business
Administration that this final rule would not have a significant
economic impact on a substantial number of small entities. Hilcorp is
the sole entity that is subject to the requirements in these
regulations, and Hilcorp is not a small governmental jurisdiction,
small organization, or small business, as defined by the RFA. Because
of this certification, a regulatory flexibility analysis is not
required and none has been prepared.
Notwithstanding any other provision of law, no person is required
to respond to nor shall a person be subject to a penalty for failure to
comply with a collection of information subject to the requirements of
the Paperwork Reduction Act (PRA) unless that collection of information
displays a currently valid OMB control number. This final rule contains
collection-of-information requirements subject to the provisions of the
PRA. These requirements have been approved by OMB under control number
0648-0151 and include applications for regulations, subsequent LOAs,
and reports.
List of Subjects in 50 CFR Part 217
Administrative practice and procedure, Alaska, Endangered and
threatened species, Indians, Marine mammals, Oil and gas exploration,
Reporting and recordkeeping requirements, Wildlife.
Dated: December 11, 2019.
Samuel D. Rauch III,
Deputy Assistant Administrator for Regulatory Programs, National Marine
Fisheries Service.
For reasons set forth in the preamble, 50 CFR part 217 is amended
as follows:
PART 217--REGULATIONS GOVERNING THE TAKE OF MARINE MAMMALS
INCIDENTAL TO SPECIFIED ACTIVITIES
0
1. The authority citation for part 217 continues to read as follows:
Authority: 16 U.S.C. 1361 et seq., unless otherwise noted.
0
2. Add subpart D to part 217 to read as follows:
Subpart D--Taking Marine Mammals Incidental to Construction and
Operation of the Liberty Drilling and Production Island
Sec.
217.30 Specified activity and specified geographical region.
217.31 Effective dates.
217.32 Permissible methods of taking.
217.33 Prohibitions.
217.34 Mitigation requirements.
217.35 Requirements for monitoring and reporting.
217.36 Letters of Authorization.
217.37 Renewals and modifications of Letters of Authorization.
217.38-217.39 [Reserved]
Subpart D--Taking Marine Mammals Incidental to Construction and
Operation of the Liberty Drilling and Production Island
Sec. 217.30 Specified activity and specified geographical region.
(a) Regulations in this subpart apply only to Hilcorp LLC (Hilcorp)
and those persons it authorizes or funds to conduct activities on its
behalf for the taking of marine mammals that occurs in the areas
outlined in paragraph (b) of this section and that occurs incidental to
construction, maintenance, and operation of the Liberty Drilling and
Production Island (LDPI) and associated infrastructure.
(b) The taking of marine mammals by Hilcorp may be authorized in a
Letter of Authorization (LOA) only if it occurs within the Beaufort
Sea, Alaska.
Sec. 217.31 Effective dates.
Regulations in this subpart are effective from December 1, 2021,
through November 30, 2026.
Sec. 217.32 Permissible methods of taking.
Under LOAs issued pursuant to Sec. Sec. 216.106 of this chapter
and 217.36, the Holder of the LOA (hereinafter ``Hilcorp'') may
incidentally, but not intentionally, take marine mammals within the
area described in Sec. 217.30(b) by mortality, serious injury, Level A
harassment, or Level B harassment associated with the LDPI construction
and operation activities, including associated infrastructure, provided
the activities are in compliance with all terms, conditions, and
requirements of the regulations in this subpart and the appropriate
LOA.
Sec. 217.33 Prohibitions.
Notwithstanding takings contemplated in Sec. 217.32 and authorized
by an LOA issued under Sec. Sec. 216.106 of this chapter and 217.36,
no person in connection with the activities described in Sec. 217.30
may:
(a) Violate, or fail to comply with, the terms, conditions, and
requirements of this subpart or an LOA issued under Sec. Sec. 216.106
of this chapter and 217.36;
(b) Take any marine mammal not specified in such LOAs;
(c) Take any marine mammal specified in such LOAs in any manner
other than as specified;
(d) Take a marine mammal specified in such LOAs if the National
Marine Fisheries Service (NMFS) determines such taking results in more
than a negligible impact on the species or stocks of such marine
mammal; or
(e) Take a marine mammal specified in such LOAs if NMFS determines
such
[[Page 70323]]
taking results in an unmitigable adverse impact on the species or stock
of such marine mammal for taking for subsistence uses.
Sec. 217.34 Mitigation requirements.
When conducting the activities identified in Sec. 217.30(a), the
mitigation measures contained in any LOA issued under Sec. 216.106 of
this chapter must be implemented. These mitigation measures shall
include but are not limited to:
(a) General conditions. (1) Hilcorp must renew, on an annual basis,
the Plan of Cooperation (POC), throughout the life of the regulations
in this subpart;
(2) A copy of any issued LOA must be in the possession of Hilcorp,
its designees, and work crew personnel operating under the authority of
the issued LOA;
(3) Hilcorp must conduct briefings for construction and ice road
supervisors and crews, and the marine mammal and acoustic monitoring
teams prior to the start of annual ice road or LDPI construction, and
when new personnel join the work, in order to explain responsibilities,
communication procedures, the marine mammal monitoring protocol, and
operational procedures;
(4) Hilcorp must allow subsistence hunters to use the LDPI for safe
harbor during severe storms, if requested by hunters;
(5) In the unanticipated event of an oil spill during LDPI
operational years, Hilcorp must notify NMFS of the spill within 48
hours, regardless of size, and implement measures contained within the
Liberty Oil Spill Response Plan; and
(6) Hilcorp must strive to complete pile driving and pipeline
installation during the ice-covered season.
(7) Except during takeoff and landing and in emergency situations,
aircraft must maintain an altitude of at least 457 m (1,500 ft). If a
marine mammal is observed, then a horizontal distance of 305 m (100 ft)
of whales or seals will be maintained between the aircraft and the
observed marine mammals.
(b) Ice road construction, maintenance, and operation. (1) Hilcorp
must implement the NMFS-approved Ice Road and Ice Trail Best Management
Practices (BMPs) and the Wildlife Action Plan. These documents may be
updated as needed throughout the life of the regulations in this
subpart, in consultation with NMFS.
(2) Hilcorp must not approach ringed seal structures (i.e., lairs
or breathing holes) within 150 m or ringed seals within 50 m.
(c) Liberty Drilling Production Island construction. (1) For all
pile driving and construction activities involving heavy equipment,
Hilcorp must implement a minimum shutdown zone of 10 meters (m) from
any marine mammal in water or seals on land. If a marine mammal comes
within or is about to enter the shutdown zone, such operations must
cease immediately;
(2) For all pile driving activity, Hilcorp shall implement shutdown
zones with radial distances as identified in any LOA issued under
Sec. Sec. 216.106 of this chapter and 217.36. If a marine mammal comes
within or is about to enter the shutdown zone, such operations must
cease immediately. NMFS may adjust the shutdown zones pending review
and approval of an acoustic monitoring report (see Sec. 217.35);
(3) Hilcorp must employ NMFS-approved protected species observers
(PSOs) and designate monitoring zones with radial distances as
identified in any LOA issued under Sec. Sec. 216.106 of this chapter
and 217.36. NMFS may adjust the monitoring zones pending review and
approval of an acoustic monitoring report (see Sec. 217.35);
(4) If a bowhead whale or other low frequency cetacean enters the
Level A harassment zone, pile or pipe driving must be shut down
immediately. If a beluga whale or pinniped enters the Level A
harassment zone while pile driving is ongoing, work may continue until
the pile is completed (estimated to require approximately 15-20
minutes), but additional pile driving must not be initiated until the
animal has left the Level A harassment zone. During this time, PSOs
must monitor the animal and record behavior;
(5) If a marine mammal is approaching a Level A harassment zone and
pile driving has not commenced, pile driving must be delayed. Pile
driving may not commence or resume until either the animal has
voluntarily left and been visually confirmed beyond the shutdown zone;
15 minutes have passed without subsequent detections of small cetaceans
and pinnipeds; or 30 minutes have passed without subsequent detections
of large cetaceans;
(6) If a species for which authorization has not been granted, or a
species for which authorization has been granted but the authorized
takes are met, is observed approaching or within the monitoring zone
(which equates to the Level B harassment zone), pile driving and
removal activities must shut down immediately using delay and shut-down
procedures. Activities must not resume until the animal has been
confirmed to have left the area or the observation time period, as
indicated in paragraph (c)(5) of this section, has elapsed;
(7) Hilcorp must use soft start techniques when impact pile
driving. Soft start requires contractors to provide an initial set of
strikes at reduced energy, followed by a thirty-second waiting period,
then two subsequent reduced energy strike sets. A soft start must be
implemented at the start of each day's impact pile driving and at any
time following cessation of impact pile driving for a period of thirty
minutes or longer;
(8) All pipe- and pile-driving activities (impact and vibratory)
and LDPI support vessel traffic outside the barrier islands must cease
by August 1, annually, and not resume until the official end of the
hunt or until the quota has been met, whichever occurs first. Hilcorp
must coordinate annually with subsistence users on the dates of these
hunts; and
(9) Should an ice seal be observed on or near the LDPI by any
Hilcorp personnel, during construction or operation, the sighting must
be reported to Hilcorp's Environmental Specialist. No construction
activity should occur within 10 m of an ice seal and any vehicles used
should use precaution and not approach any ice seal within 10 m.
(d) Vessel restrictions. When operating vessels, Hilcorp must:
(1) Reduce vessel speed to 5 knots (kn) if a whale is observed
within 500 m (1641 feet (ft)) of the vessel and is on a potential
collision course with the vessel, or if a vessel is within 275 m (902
ft) of whales, regardless of course relative to the vessel;
(2) Avoid multiple changes in vessel direction;
(3) Not approach within 800 m (2,624 ft) of a North Pacific right
whale or within 5.6 km (3 nautical miles) of Steller sea lion rookeries
or major haulouts; and
(4) Avoid North Pacific right whale critical habitat or, if
critical habitat cannot be avoided, reduce vessel speed during transit.
Sec. 217.35 Requirements for monitoring and reporting.
(a) All marine mammal and acoustic monitoring must be conducted in
accordance to Hilcorp's Marine Mammal Mitigation and Monitoring Plan
(4MP) and Acoustic Monitoring Plan, which includes acoustic monitoring
during both the open-water and ice-covered seasons. These plans may be
modified throughout the life of
[[Page 70324]]
the regulations in this subpart upon NMFS review and approval.
(b) Monitoring must be conducted by NMFS-approved PSOs, who must
have no other assigned tasks during monitoring periods and be equipped
with, at minimum, binoculars and rangefinders. At minimum, two PSOs
must be placed on elevated platforms on the island during the open-
water season when island construction activities are occurring. These
observers will monitor for marine mammals and implement shutdown or
delay procedures when applicable through communication with the
equipment operator.
(c) One PSO will be placed on the side where construction
activities are taking place and the other placed on the opposite side
of the LDPI; both observers will be on elevated platforms.
(d) PSOs will rotate duties such that they will observe for no more
than 4 hours at a time and no more than 12 hours in a 24-hour period.
(e) An additional island-based PSO will work with an aviation
specialist to use an unmanned aircraft system (UAS) to detect marine
mammals in the monitoring zones during pile and pipe driving and slope
shaping. Should UAS monitoring not be feasible or be deemed
ineffective, a boat-based PSO must monitor for marine mammals during
pile and pipe driving.
(f) During the open-water season, marine mammal monitoring must
take place from 30 minutes prior to initiation of pile and pipe driving
activity through 30 minutes post-completion of pile driving activity.
Pile driving may commence when observers have declared the shutdown
zone clear of marine mammals. In the event of a delay or shutdown of
activity resulting from marine mammals in the shutdown zone, animals
must be allowed to remain in the shutdown zone (i.e., must leave of
their own volition) and their behavior must be monitored and
documented.
(g) After island construction is complete but drilling activities
are occurring, a PSO will be stationed on the LDPI for approximately 4
weeks during the month of August to monitor for the presence of marine
mammals around the island in the monitoring zone.
(1) Marine mammal monitoring during pile driving and removal must
be conducted by NMFS-approved PSOs in a manner consistent with the
following:
(i) At least one observer must have prior experience working as an
observer;
(ii) Other observers may substitute education (degree in biological
science or a related field) or training for experience;
(iii) Where a team of three or more observers are required, one
observer must be designated as lead observer or monitoring coordinator.
The lead observer must have prior experience working as an observer;
and
(iv) Hilcorp must submit PSO curricula vitae (CVs) for approval by
NMFS prior to the onset of pile driving.
(2) PSOs must have the following additional qualifications:
(i) Ability to conduct field observations and collect data
according to assigned protocols;
(ii) Experience or training in the field identification of marine
mammals, including the identification of behaviors;
(iii) Sufficient training, orientation, or experience with the
construction operation to provide for personal safety during
observations;
(iv) Writing skills sufficient to prepare a report of observations
including, but not limited to, the number and species of marine mammals
observed; dates and times when in-water construction activities were
conducted; dates, times, and reason for implementation of mitigation
(or why mitigation was not implemented when required); and marine
mammal behavior; and
(v) Ability to communicate orally, by radio or in person, with
project personnel to provide real-time information on marine mammals
observed in the area as necessary.
(h) Hilcorp must deploy autonomous sound recorders on the seabed to
conduct underwater passive acoustic monitoring in the open-water season
the first four years of the project such that island construction
activities, including pile driving, and drilling operations are
recorded. Acoustic monitoring will be conducted for the purposes of
sound source verification to verify distances from noise sources at
which underwater sound levels reach thresholds for potential marine
mammal harassment.
(i) Hilcorp must submit incident and monitoring reports.
(1) Hilcorp must submit a draft annual marine mammal and acoustic
summary report to NMFS not later than 90 days following the end of each
calendar year. Hilcorp must provide a final report within 30 days after
receipt of NMFS' comments on the draft report. The reports must
contain, at a minimum, the following:
(i) Date and time that monitored activity begins or ends;
(ii) Description of construction activities occurring during each
observation period;
(iii) Weather parameters (e.g., wind speed, percent cloud cover,
visibility);
(iv) Water conditions (e.g., sea state, tide state);
(v) Species, numbers, and, if possible, sex and age class of marine
mammals observed;
(vi) Description of any observable marine mammal behavior patterns,
including bearing and direction of travel and distance from
construction activity;
(vii) Distance from construction activities to marine mammals and
distance from the marine mammals to the observation point;
(viii) An extrapolated total take estimate for each species based
on the number of marine mammals observed and the extent of the
harassment zones during the applicable construction activities;
(ix) Histograms of the perpendicular distance at which marine
mammals were sighted by the PSOs;
(x) Description of implementation of mitigation measures (e.g.,
shutdown or delay);
(xi) Locations of all marine mammal observations;
(xii) An estimate of the effective strip width of the island-based
PSOs and the UAS imagery; and
(xiii) Sightings and locations of marine mammals associated with
acoustic detections.
(2) Annually, Hilcorp must submit a report within 90 days of ice
road decommissioning. The report must include the following:
(i) Date, time, location of observation;
(ii) Ringed seal characteristics (i.e., adult or pup, behavior
(avoidance, resting, etc.));
(iii) Activities occurring during observation, including equipment
being used and its purpose, and approximate distance to ringed seal(s);
(iv) Actions taken to mitigate the effects of interaction,
emphasizing: which BMPs were successful; which BMPs may need to be
improved to reduce interactions with ringed seals; the effectiveness
and practicality of implementing BMPs; any issues or concerns regarding
implementation of BMPs; and potential effects of interactions based on
observation data;
(v) Proposed updates (if any) to the NMFS-approved Wildlife
Management Plan(s) or the ice-road BMPs; and
(vi) Reports should be able to be queried for information.
(3) Hilcorp must submit a final 5-year comprehensive summary report
to NMFS not later than 90 days following the expiration of this subpart
and LOA.
(4) Hilcorp must submit acoustic monitoring reports per the
Acoustic Monitoring Plan.
(5) Hilcorp must report on observed injured or dead marine mammals.
[[Page 70325]]
(i) In the unanticipated event that the activity defined in Sec.
217.30 clearly causes the take of a marine mammal in a prohibited
manner, Hilcorp must immediately cease such activity and report the
incident to the Office of Protected Resources (OPR), NMFS, and to the
Alaska Regional Stranding Coordinator, NMFS. Activities must not resume
until NMFS is able to review the circumstances of the prohibited take.
NMFS will work with Hilcorp to determine what measures are necessary to
minimize the likelihood of further prohibited take and ensure Marine
Mammal Protection Act (MMPA) compliance. Hilcorp may not resume their
activities until notified by NMFS. The report must include the
following information:
(A) Time, date, and location (latitude/longitude) of the incident;
(B) Description of the incident;
(C) Environmental conditions (e.g., wind speed and direction,
Beaufort sea state, cloud cover, visibility);
(D) Description of all marine mammal observations in the 24 hours
preceding the incident;
(E) Species identification or description of the animal(s)
involved;
(F) Fate of the animal(s); and
(G) Photographs or video footage of the animal(s). Photographs may
be taken once the animal has been moved from the waterfront area.
(H) In the event that Hilcorp discovers an injured or dead marine
mammal and determines that the cause of the injury or death is unknown
and the death is relatively recent (e.g., in less than a moderate state
of decomposition), Hilcorp must immediately report the incident to OPR
and the Alaska Regional Stranding Coordinator, NMFS. The report must
include the information identified in paragraph (i)(5)(i) of this
section. Activities may continue while NMFS reviews the circumstances
of the incident. NMFS will work with Hilcorp to determine whether
additional mitigation measures or modifications to the activities are
appropriate.
(ii) In the event Hilcorp discovers an injured or dead marine
mammal and determines that the injury or death is not associated with
or related to the activities defined in Sec. 217.30 (e.g., previously
wounded animal, carcass with moderate to advanced decomposition,
scavenger damage), Hilcorp must report the incident to OPR and the
Alaska Regional Stranding Coordinator, NMFS, within 24 hours of the
discovery. Hilcorp must provide photographs or video footage or other
documentation of the stranded animal sighting to NMFS. Photographs may
be taken once the animal has been moved from the waterfront area.
Sec. 217.36 Letters of Authorization.
(a) To incidentally take marine mammals pursuant to this subpart,
Hilcorp must apply for and obtain an LOA.
(b) An LOA, unless suspended or revoked, may be effective for a
period of time not to exceed the expiration date of this subpart.
(c) If an LOA expires prior to the expiration date of this subpart,
Hilcorp may apply for and obtain a renewal of the LOA.
(d) In the event of projected changes to the activity or to
mitigation and monitoring measures required by an LOA, Hilcorp must
apply for and obtain a modification of the LOA as described in Sec.
217.37.
(e) The LOA shall set forth:
(1) Permissible methods of incidental taking;
(2) Means of effecting the least practicable adverse impact (i.e.,
mitigation) on the species, its habitat, and on the availability of the
species for subsistence uses; and
(3) Requirements for monitoring and reporting.
(f) Issuance of the LOA shall be based on a determination that the
level of taking will be consistent with the findings made for the total
taking allowable under this subpart.
(g) Notice of issuance or denial of an LOA shall be published in
the Federal Register within thirty days of a determination.
Sec. 217.37 Renewals and modifications of Letters of Authorization.
(a) An LOA issued under Sec. Sec. 216.106 of this chapter and
217.36 for the activity identified in Sec. 217.30(a) shall be renewed
or modified upon request by the applicant, provided that:
(1) The proposed specified activity and mitigation, monitoring, and
reporting measures, as well as the anticipated impacts, are the same as
those described and analyzed for this subpart (excluding changes made
pursuant to the adaptive management provision in paragraph (c)(1) of
this section); and
(2) NMFS determines that the mitigation, monitoring, and reporting
measures required by the previous LOA under this subpart were
implemented.
(b) For LOA modification or renewal requests by the applicant that
include changes to the activity or the mitigation, monitoring, or
reporting (excluding changes made pursuant to the adaptive management
provision in paragraph (c)(1) of this section) that do not change the
findings made for this subpart or result in no more than a minor change
in the total estimated number of takes (or distribution by species or
years), NMFS may publish a notice of proposed LOA in the Federal
Register, including the associated analysis of the change, and solicit
public comment before issuing the LOA.
(c) An LOA issued under Sec. Sec. 216.106 of this chapter and
217.36 for the activity identified in Sec. 217.30(a) may be modified
by NMFS under the following circumstances:
(1) Adaptive management. NMFS may modify (including augment) the
existing mitigation, monitoring, or reporting measures (after
consulting with Hilcorp regarding the practicability of the
modifications) if doing so creates a reasonable likelihood of more
effectively accomplishing the goals of the mitigation and monitoring
set forth in this subpart.
(i) Possible sources of data that could contribute to the decision
to modify the mitigation, monitoring, or reporting measures in an LOA:
(A) Results from Hilcorp's monitoring from the previous year(s).
(B) Results from other marine mammal and/or sound research or
studies.
(C) Any information that reveals marine mammals may have been taken
in a manner, extent, or number not authorized by this subpart or
subsequent LOAs.
(ii) If, through adaptive management, the modifications to the
mitigation, monitoring, or reporting measures are substantial, NMFS
will publish a notice of proposed LOA in the Federal Register and
solicit public comment.
(2) Emergencies. If NMFS determines that an emergency exists that
poses a significant risk to the well-being of the species or stocks of
marine mammals specified in LOAs issued pursuant to Sec. Sec. 216.106
of this chapter and 217.36, an LOA may be modified without prior notice
or opportunity for public comment. Notice would be published in the
Federal Register within thirty days of the action.
Sec. Sec. 217.38-217.39 [Reserved]
[FR Doc. 2019-27049 Filed 12-19-19; 8:45 am]
BILLING CODE 3510-22-P