Marine Mammals; Incidental Take During Specified Activities; North Slope, Alaska

DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

50 CFR Part 18

Docket No. FWS-R7-ES-2021-0037; FXES111607MRG01-212-FF07CAMM00]

RIN 1018-BF13

Marine Mammals; Incidental Take During Specified Activities; North Slope, Alaska

AGENCY:

Fish and Wildlife Service, Interior.

ACTION:

Final rule.

SUMMARY:

We, the U.S. Fish and Wildlife Service, in response to a request from the Alaska Oil and Gas Association, finalize regulations authorizing the nonlethal, incidental, unintentional take by harassment of small numbers of polar bears and Pacific walruses during year-round oil and gas industry activities in the Beaufort Sea (Alaska and the Outer Continental Shelf) and adjacent northern coast of Alaska. Take may result from oil and gas exploration, development, production, and transportation activities occurring for a period of 5 years. These activities are similar to those covered by the previous 5-year Beaufort Sea incidental take regulations effective from August 5, 2016, through August 5, 2021. This rule authorizes take by harassment only. No lethal take is authorized. We will issue Letters of Authorization, upon request, for specific activities in accordance with these regulations.

DATES:

This rule is effective August 5, 2021, and remains effective through August 5, 2026.

ADDRESSES:

You may view this rule, the associated final environmental assessment and U.S. Fish and Wildlife Service finding of no significant impact (FONSI), and other supporting material at

http://www.regulations.gov

under Docket No. FWS-R7-ES-2021-0037, or these documents may be requested as described under

FOR FURTHER INFORMATION CONTACT

.

FOR FURTHER INFORMATION CONTACT:

Marine Mammals Management, U.S. Fish and Wildlife Service, 1011 East Tudor Road, MS-341, Anchorage, AK 99503, Telephone 907-786-3844, or Email:

R7mmmregulatory@fws.gov.

Persons who use a telecommunications device for the deaf (TDD) may call the Federal Relay Service (FRS) at 1-800-877-8339, 24 hours a day, 7 days a week.

SUPPLEMENTARY INFORMATION:

Immediate Promulgation

In accordance with the Administrative Procedure Act (APA; 5 U.S.C. 553(d)(3)), we find that we have good cause to make this rule effective less than 30 days after publication. Immediate promulgation of the rule will ensure that the applicant will implement mitigation measures and monitoring programs in the geographic region that reduce the risk of harassment of polar bears (

Ursus maritimus

) and Pacific walruses (

Odobenus rosmarus divergens

) by their activities.

Executive Summary

In accordance with the Marine Mammal Protection Act (MMPA) of 1972, as amended, and its implementing regulations, we, the U.S. Fish and Wildlife Service (Service or we), finalize incidental take regulations (ITRs) that authorize the nonlethal, incidental, unintentional take of small numbers of Pacific walruses and polar bears during oil and gas industry (hereafter referred to as “Industry”) activities in the Beaufort Sea and adjacent northern coast of Alaska, not including lands within the Arctic National Wildlife Refuge, for a 5-year period. Industry operations include similar types of activities covered by the previous 5-year Beaufort Sea ITRs effective from August 5, 2016, through August 5, 2021 (81 FR 52276).

This rule is based on our findings that the total takings of Pacific walruses (walruses) and polar bears during Industry activities will impact no more than small numbers of animals, will have a negligible impact on these species or stocks, and will not have an unmitigable adverse impact on the availability of these species or stocks for taking for subsistence uses by Alaska Natives. We base our findings on past and proposed future monitoring of the encounters and interactions between these species and Industry; species research; oil spill risk assessments; potential and documented Industry effects on these species; natural history and conservation status information of these species; and data reported from Alaska Native subsistence hunters. We have prepared a National Environmental Policy Act (NEPA) environmental assessment (EA) in conjunction with this rulemaking and determined that this final action will result in a finding of no significant impact (FONSI).

These regulations include permissible methods of nonlethal taking; mitigation measures to ensure that Industry activities will have the least practicable adverse impact on the species or stock, their habitat, and their availability for subsistence uses; and requirements for monitoring and reporting. Compliance with this rule is not expected to result in significant additional costs to Industry, and any costs are minimal in comparison to those related to actual oil and gas exploration, development, and production operations.

Background

Section 101(a)(5)(A) of the Marine Mammal Protection Act (MMPA; 16 U.S.C. 1371(a)(5)(A)) gives the Secretary of the Interior (Secretary) the authority to allow the incidental, but not intentional, taking of small numbers of marine mammals, in response to requests by U.S. citizens (as defined in 50 CFR 18.27(c)) engaged in a specified activity (other than commercial fishing) within a specified geographic region. The Secretary has delegated authority for implementation of the MMPA to the U.S. Fish and Wildlife Service. According to the MMPA, the Service shall allow this incidental taking if we find the total of such taking for a 5-year period or less:

(1) Will affect only small numbers of marine mammals of a species or population stock;

(2) will have no more than a negligible impact on such species or stocks;

(3) will not have an unmitigable adverse impact on the availability of such species or stocks for taking for subsistence use by Alaska Natives; and

(4) we issue regulations that set forth:

(a) Permissible methods of taking;

(b) other means of effecting the least practicable adverse impact on the species or stock and its habitat, and on the availability of such species or stock for subsistence uses; and

(c) requirements for monitoring and reporting of such taking.

If final regulations allowing such incidental taking are issued, we may then subsequently issue Letters of Authorization (LOAs), upon request, to authorize incidental take during the specified activities.

The term “take” as defined by the MMPA, means to harass, hunt, capture, or kill, or attempt to harass, hunt, capture, or kill any marine mammal (16 U.S.C. 1362(13)). Harassment, as defined by the MMPA, for activities other than military readiness activities or scientific research conducted by or on behalf of the Federal Government, means “any act of pursuit, torment, or annoyance which (i) has the potential to injure a marine mammal or marine mammal stock in the wild” (the MMPA defines this as Level A harassment); or “(ii) has the potential to disturb a

marine mammal or marine mammal stock in the wild by causing disruption of behavioral patterns, including, but not limited to, migration, breathing, nursing, breeding, feeding, or sheltering” (the MMPA defines this as Level B harassment) (16 U.S.C. 1362(18)).

The terms “negligible impact” and “unmitigable adverse impact” are defined in title 50 of the CFR at 50 CFR 18.27 (the Service's regulations governing small takes of marine mammals incidental to specified activities). “Negligible impact” is an impact resulting from the specified activity that cannot be reasonably expected to, and is not reasonably likely to, adversely affect the species or stock through effects on annual rates of recruitment or survival. “Unmitigable adverse impact” means an impact resulting from the specified activity (1) that is likely to reduce the availability of the species to a level insufficient for a harvest to meet subsistence needs by (i) causing the marine mammals to abandon or avoid hunting areas, (ii) directly displacing subsistence users, or (iii) placing physical barriers between the marine mammals and the subsistence hunters; and (2) that cannot be sufficiently mitigated by other measures to increase the availability of marine mammals to allow subsistence needs to be met.

The term “small numbers”; is also defined in 50 CFR 18.27. However, we do not rely on that definition here as it conflates “small numbers” with “negligible impacts.” We recognize “small numbers” and “negligible impacts” as two separate and distinct requirements for promulgating incidental take regulations (ITRs) under the MMPA (see

Natural Res. Def. Council, Inc.

v.

Evans,

232 F. Supp. 2d 1003, 1025 (N.D. Cal. 2003)). Instead, for our small numbers determination, we estimate the likely number of takes of marine mammals and evaluate if that take is small relative to the size of the species or stock.

The term “least practicable adverse impact” is not defined in the MMPA or its enacting regulations. For this ITR, we ensure the least practicable adverse impact by requiring mitigation measures that are effective in reducing the impact of Industry activities but are not so restrictive as to make Industry activities unduly burdensome or impossible to undertake and complete.

In this ITR, the term “Industry” includes individuals, companies, and organizations involved in exploration, development, production, extraction, processing, transportation, research, monitoring, and support services of the petroleum industry that were named in the request for this regulation. Industry activities may result in the incidental taking of Pacific walruses and polar bears.

The MMPA does not require Industry to obtain an incidental take authorization; however, any taking that occurs without authorization is a violation of the MMPA. Since 1993, the oil and gas industry operating in the Beaufort Sea and the adjacent northern coast of Alaska has requested and we have issued ITRs for the incidental take of Pacific walruses and polar bears within a specified geographic region during specified activities. For a detailed history of our current and past Beaufort Sea ITRs, refer to the

Federal Register

at 81 FR 52276, August 5, 2016; 76 FR 47010, August 3, 2011; 71 FR 43926, August 2, 2006; and 68 FR 66744, November 28, 2003. The current regulations are codified at 50 CFR part 18, subpart J (§§ 18.121 to 18.129).

Summary of Request

On June 15, 2020, the Service received a request from the Alaska Oil and Gas Association (AOGA) on behalf of its members and other participating companies to promulgate regulations for nonlethal incidental take of small numbers of walruses and polar bears in the Beaufort Sea and adjacent northern coast of Alaska for a period of 5 years (2021-2026) (hereafter referred to as “the Request”). We received an amendment to the Request on March 9, 2021, which was deemed adequate and complete. The amended Request is available at

www.regulations.gov

at Docket No. FWS-R7-ES-2021-0037.

The AOGA Request requested regulations that will be applicable to the oil and gas exploration, development, and production, extraction, processing, transportation, research, monitoring, and support activities of multiple companies specified in the Request. This includes AOGA member and other non-member companies that have applied for these regulations and their subcontractors and subsidiaries that plan to conduct oil and gas operations in the specified geographic region. Members of AOGA represented in the Request are: Alyeska Pipeline Service Company, BlueCrest Energy, Inc., Chevron Corporation, ConocoPhillips Alaska, Inc. (CPAI), Eni U.S. Operating Co. Inc. (Eni Petroleum), ExxonMobil Alaska Production Inc. (ExxonMobil), Furie Operating Alaska, LLC, Glacier Oil and Gas Corporation (Glacier), Hilcorp Alaska, LLC (Hilcorp), Marathon Petroleum, Petro Star Inc., Repsol, and Shell Exploration and Production Company (Shell).

Non-AOGA companies represented in the Request are: Alaska Gasline Development Corporation (AGDC), Arctic Slope Regional Corporation (ASRC) Energy Services, Oil Search (Alaska), LLC, and Qilak LNG, Inc. This rule applies only to AOGA members, the non-members noted above, their subsidiaries and subcontractors, and companies that have been or will be acquired by any of the above. The activities and geographic region specified in AOGA's Request and considered in this rule are described below in the sections titled Description of Specified Activities and Description of Specified Geographic Region.

Summary of Changes From the Proposed ITR

In preparing this final rule for the incidental take of polar bears and Pacific walruses, we reviewed and considered comments and information from the public on our proposed rule published in the

Federal Register

on June 1, 2021 (86 FR 29364). We also reviewed and considered comments and information from the public for our draft environmental assessment (EA). Based on those considerations, we are finalizing these regulations with the following changes from our proposed rule:

• The Service revised language to state: “Aircraft operations within the ITR area should maintain an altitude of 1,500 ft above ground level when safe and operationally possible.” The inclusion of “safe and” is essential to clarify that this altitude recommendation applies only when it is safe to do so (in addition to when it is “operationally possible”).

• The Service added language to state that, where information is insufficient to evaluate the potential effects of activities on walruses, polar bears, and the subsistence use of these species, holders of an LOA may be required to participate in joint monitoring and/or research efforts to address these information needs and ensure the least practicable impact to these resources.

• The Service added language specifying that a group be defined for both walruses and polar bears as being two or more individuals.

• The Service added language that clarifies that the correct geographic region to which the ITRs will apply is 50 miles offshore, not 200 miles offshore.

• The Service has revised Table 1 in the preamble to include details regarding the sound measurement units and included peak SPL for impulsive sound sources. The Service has also

revised references to past ITR Level B harassment and TTS thresholds.

• The Service has added clarifying language to reflect the numbers of leases and land area in the NPR-A to reflect 307 leases covering 2.6 million acres.

• The Service added a recent peer-reviewed article, “Polar bear behavioral response to vessel surveys in northeastern Chukchi Sea, 2008-2014” by Lomac-MacNair et al. (2021), which assisted with the analysis of behavioral responses of polar bears to vessel activity.

• The Service has clarified our discussion regarding the conclusions we drew from the peer-reviewed article “Aquatic behaviour of polar bears (

Ursus maritimus

) in an increasingly ice-free Arctic.” Lone, et al. 2018.

• The Service added language to clarify information requirements from applicants for LOAs and have clarified our discussion regarding monthly human occupancy.

• The Service added clarifying language to § 18.126(b)(4) to limit disturbance around dens, including putative and verified dens.

• The Service has removed the term “other substantially similar” when describing what proposed activities are covered under these ITRs.

Description of the Regulations

This rule does not authorize or “permit” the specified activities to be conducted by the applicant. Rather, it authorizes the nonlethal, incidental, unintentional take of small numbers of Pacific walruses and polar bears that may result from Industry activities based on standards set forth in the MMPA. The Bureau of Ocean Energy Management (BOEM), the Bureau of Safety and Environmental Enforcement, the U.S. Army Corps of Engineers, and the Bureau of Land Management (BLM) are responsible for permitting activities associated with Industry activities in Federal waters and on Federal lands. The State of Alaska is responsible for permitting Industry activities on State lands and in State waters. The regulations include:

• Permissible methods of nonlethal taking;

• Measures designed to ensure the least practicable adverse impact on Pacific walruses and polar bears and their habitat, and on the availability of these species or stocks for subsistence uses; and

• Requirements for monitoring and reporting.

Description of Letters of Authorization (LOAs)

An LOA is required to conduct activities pursuant to an ITR. Under this ITR, entities intending to conduct the specific activities described in these regulations may request an LOA for the authorized nonlethal, incidental Level B harassment of walruses and polar bears. Per AOGA's Request, such entities would be limited to the companies, groups, individuals specified in AOGA's Request, their subsidiaries or subcontractors, and their successors-in-interest. Requests for LOAs must be consistent with the activity descriptions and mitigation and monitoring requirements of the ITR and be received in writing at least 90 days before the activity is to begin. Requests must include (1) an operational plan for the activity; (2) a digital geospatial file of the project footprint, (3) estimates of monthly human occupancy (

i.e.,

a percentage that represents the amount of the month that at least one human is occupying a given location) of project area; (4) a walrus and/or polar bear interaction plan, (5) a site-specific marine mammal monitoring and mitigation plan that specifies the procedures to monitor and mitigate the effects of the activities on walruses and/or polar bears, including frequency and dates of aerial infrared (AIR) surveys if such surveys are required, and (6) Plans of Cooperation (described below). Once this information has been received, we will evaluate each request and issue the LOA if we find that the level of taking will be consistent with the findings made for the total taking allowable under the ITR and all other requirements of these regulations are met. We must receive an after-action report on the monitoring and mitigation activities within 90 days after the LOA expires. For more information on requesting and receiving an LOA, refer to 50 CFR 18.27.

Description of Plans of Cooperation (POCs)

A POC is a documented plan describing measures to mitigate potential conflicts between Industry activities and Alaska Native subsistence hunting. The circumstances under which a POC must be developed and submitted with a request for an LOA are described below.

To help ensure that Industry activities do not have an unmitigable adverse impact on the availability of the species for subsistence hunting opportunities, all applicants requesting an LOA under this ITR must provide the Service documentation of communication and coordination with Alaska Native communities potentially affected by the Industry activity and, as appropriate, with representative subsistence hunting and co-management organizations, such as the North Slope Borough, the Alaska Nannut Co-Management Council (ANCC), and Eskimo Walrus Commission (EWC), among others. If Alaska Native communities or representative subsistence hunting organizations express concerns about the potential impacts of project activities on subsistence activities, and such concerns are not resolved during this initial communication and coordination process, then a POC must be developed and submitted with the applicant's request for an LOA. In developing the POC, Industry representatives will further engage with Alaska Native communities and/or representative subsistence hunting organizations to provide information and respond to questions and concerns. The POC must provide adequate measures to ensure that Industry activities will not have an unmitigable adverse impact on the availability of walruses and polar bears for Alaska Native subsistence uses.

Description of Specified Geographic Region

The specified geographic region covered by the requested ITR (Beaufort Sea ITR region (Figure 1)) encompasses all Beaufort Sea waters (including State waters and Outer Continental Shelf waters as defined by BOEM) east of a north-south line extending from Point Barrow (N71.39139, W156.475, BGN 1944) to the Canadian border, except for marine waters located within the Arctic National Wildlife Refuge (ANWR). The offshore boundary extends 80.5 km (50 mi) offshore. The onshore boundary includes land on the North Slope of Alaska from Point Barrow to the western boundary of ANWR. The onshore boundary is 40 km (25 mi) inland. No lands or waters within the exterior boundaries of ANWR are included in the Beaufort Sea ITR region. The geographical extent of the Beaufort Sea ITR region (approximately 7.9 million hectares (ha) (~19.8 million acres (ac))) is smaller than the region covered in previous regulations (approximately 29.8 million ha (~73.6 million ac) were included in the ITR set forth via the final rule that published at 81 FR 52276, August 5, 2016).

BILLING CODE 4333-15-P

ER05AU21.000

BILLING CODE 4333-15-C

Description of Specified Activities

This section first summarizes the type and scale of Industry activities anticipated to occur in the Beaufort Sea ITR region from 2021 to 2026 and then provides more detailed specific information on these activities. Year-round onshore and offshore Industry activities are anticipated. During the 5 years that the ITR will be in place, Industry activities are expected to be generally similar in type, timing, and effect to activities evaluated under the prior ITRs. Due to the large number of variables affecting Industry activities, prediction of exact dates and locations of activities is not possible in a request for a 5-year ITR. However, operators must provide specific dates and locations of activities in their requests for LOAs. Requests for LOAs for activities and impacts that exceed the scope of analysis and determinations for this ITR will not be issued. Additional information is available in the AOGA Request for an ITR at:

www.regulations.gov

in Docket No. FWS-R7-ES-2021-0037.

Exploration Activities

AOGA's exploration activities specified in the Request are for the purpose of exploring subsurface geology, water depths, and seafloor conditions to help inform development and production projects that may occur in those areas. Exploration survey activities include geotechnical site investigations, reflection seismic exploration, vibroseis, vertical seismic profiles, seafloor imagery collection, and offshore bathymetry collection. Exploratory drilling and development activities include onshore ice pad and road development, onshore gravel pad and road development, offshore ice road development, and artificial island development.

The location of new exploration activities within the specified geographic region of this rule will be influenced by the location of current leases as well as any new leases acquired via potential future Federal and State of Alaska oil and gas lease sales.

BOEM Outer Continental Shelf Lease Sales

BOEM manages oil and gas leases in the Alaska Outer Continental Shelf (OCS) region, which encompasses 242 million ha (600 million ac). Of that acreage, approximately 26 million ha (~65 million ac) are within the Beaufort Sea Planning Area. Ten lease sales have been held in this area since 1979, resulting in 147 active leases, where 32 exploratory wells were drilled. Production has occurred on one joint

Federal/State unit, with Federal oil production accounting for more than 28.7 million barrels (bbl) (1 bbl = 42 U.S. gallons or 159 liters) of oil since 2001 (BOEM 2016). Details regarding availability of future leases, locations, and acreages are not yet available, but exploration of the OCS may continue during the 2021-2026 timeframe of the ITR. Lease Sale 242, previously planned in the Beaufort Sea during 2017 (BOEM 2012), was cancelled in 2015. BOEM issued a notice of intent to prepare an environmental impact statement (EIS) for the 2019 Beaufort Sea lease sale in 2018 (83 FR 57749, November 16, 2018). The 2019-2024 Draft Proposed Program included three OCS lease sales, with one each in 2019, 2021, and 2023, but has not been approved. Information on the Alaska OCS Leasing Program can be found at:

https://www.boem.gov/about-boem/alaska-leasing-office.

National Petroleum Reserve—Alaska

The BLM manages the 9.2 million-ha (22.8 million-ac) Natural Petroleum Reserve—Alaska (NPR-A), of which 1.3 million ha (3.2 million ac) occur within the Beaufort Sea ITR region. Lease sales have occurred regularly in the NPR-A; 15 oil and gas lease sales have been held in the NPR-A since 1999. There are currently 307 leases covering more than 1,052,182 ha (2.6 million ac) in the NPR-A. Current operator/ownership information is available on the BLM NPR-A website at

https://www.blm.gov/programs/energy-and-minerals/oil-and-gas/leasing/regional-lease-sales/alaska.

State of Alaska Lease Sales

The State of Alaska Department of Natural Resources (ADNR), Oil and Gas Division, holds annual lease sales of State lands available for oil and gas development. Lease sales are organized by planning area. Under areawide leasing, the State offers all available State acreage not currently under lease within each area annually. AOGA's Request includes activities in the State's North Slope and Beaufort Sea planning areas. Lease sale data are available on the ADNR website at:

https://dog.dnr.alaska.gov/Services/BIFAndLeaseSale.

Projected activities may include exploration, facility maintenance and construction, and operation activities.

The North Slope planning area has 1,225 tracts that lie between the NPR-A and the ANWR. The southern boundary of the North Slope sale area is the Umiat baseline. Several lease sales have been held to date in this leasing area. As of May 2020, there are 1,505 active leases on the North Slope, encompassing 1.13 ha (2.8 million ac), and 220 active leases in the State waters of the Beaufort Sea, encompassing 244,760 ha (604,816 ac). The Beaufort Sea Planning Area encompasses a gross area of approximately 687,966 ha (1.7 million ac) divided into 572 tracts ranging in size from 210 to 2,330 ha (520 to 5,760 ac).

Development Activities

Industry operations during oil and gas development may include construction of roads, pipelines, waterlines, gravel pads, work camps (personnel, dining, lodging, and maintenance facilities), water production and wastewater treatment facilities, runways, and other support infrastructure. Activities associated with the development phase include transportation activities (automobile, airplane, and helicopter); installation of electronic equipment; well drilling; drill rig transport; personnel support; and demobilization, restoration, and remediation work. Industry development activities are often planned or coordinated by unit. A unit is composed of a group of leases covering all or part of an accumulation of oil and/or gas. Alaska's North Slope oil and gas field primary units include: Duck Island Unit (Endicott), Kuparuk River Unit, Milne Point Unit, Nikaitchuq Unit, Northstar Unit, Point Thomson Unit, Prudhoe Bay Unit, Badami Unit, Oooguruk Unit, Bear Tooth Unit, Pikka Unit, and the Colville River and Greater Mooses Tooth Units, which for the purposes of this ITR are combined into the Western North Slope.

Production Activities

North Slope production facilities occur between the oilfields of the Alpine Unit in the west to Badami and Point Thomson in the east. Production activities include building operations, oil production, oil transport, facilities, maintenance and upgrades, restoration, and remediation. Production activities are long-term and year-round activities whereas exploration and development activities are usually temporary and seasonal. Alpine and Badami are not connected to the road system and must be accessed by airstrips, barges, and seasonal ice roads. Transportation on the North Slope is by automobile, airplanes, helicopters, boats, vehicles with large, low-pressure tires called Rolligons, tracked vehicles, and snowmobiles. Aircraft, both fixed wing and helicopters, are used for movement of personnel, mail, rush-cargo, and perishable items. Most equipment and materials are transported to the North Slope by truck or barge. Much of the barge traffic during the open-water season unloads from West Dock.

Oil pipelines extend from each developed oilfield to the Trans-Alaska Pipeline System (TAPS). The 122-cm (48-in)-diameter TAPS pipeline extends 1,287 km (800 mi) from the Prudhoe Bay oilfield to the Valdez Marine Terminal. Alyeska Pipeline Service Company conducts pipeline operations and maintenance. Access to the pipeline is primarily from established roads, such as the Spine Road and the Dalton Highway, or along the pipeline right-of-way.

Oil and Gas Support Activities

In addition to oil and gas production and development activities, support activities are often performed on an occasional, seasonal, or daily basis. Support activities streamline and provide direct assistance to other activities and are necessary for Industry working across the North Slope and related areas. Several support activities are defined in AOGA's Request and include: Placement and maintenance of gravel pads, roads, and pipelines; supply operations that use trucks or buses, aircraft (fixed-wing or rotor-wing), hovercrafts, and barges/tugs to transport people, personal incidentals (food, mail, cargo, perishables, and personal items) between Units and facilities; pipeline inspections, maintenance dredging and screeding operations; and training for emergency response and oil spill response. Some of these activities are seasonal and performed in the winter using tundra-appropriate vehicles, such as road, pad, and pipeline development and inspections. Field and camp-specific support activities include: Construction of snow fences; corrosion and subsidence control and management; field maintenance campaigns; drilling; well work/work-overs; plugging and abandonment of existing wells; waste handling (oil field wastes or camp wastes); camp operations (housekeeping, billeting, dining, medical services); support infrastructure (warehousing and supplies, shipping and receiving, road and pad maintenance, surveying, inspection, mechanical shops, aircraft support and maintenance); emergency response services and trainings; construction within existing fields to support oil field infrastructure and crude oil extraction; and transportation services by a variety of vehicles. Additional details on each of these support activities can be found in AOGA's Request.

Specific Ongoing and Planned Activities at Existing Oil and Gas Facilities for 2021-2026

During the regulatory period, exploration and development activities are anticipated to occur in the offshore and continue in the current oil field units, including those projects identified by Industry, below.

Badami Unit

The Badami oilfield resides between the Point Thomson Unit and the Prudhoe Bay Unit, approximately 56 km (35 mi) east of Prudhoe Bay. No permanent road connections exist from Badami to other Units, such as Prudhoe Bay or the Dalton Highway. The Badami Unit consists of approximately 34 ha (85 ac) of tundra, including approximately 9.7 km (6 mi) of established industrial duty roads connecting all infrastructure, 56 km (35 mi) of pipeline, one gravel mine site, and two gravel pads with a total of 10 wells. The oilfield consists of the following infrastructure and facilities: A central processing facility (CPF) pad, a storage pad, the Badami airstrip pad, the Badami barge landing, and a 40.2-km (25-mi) pipeline that connects to Endicott.

During the summer, equipment and supplies are transported to Badami by contract aircraft from Merrill Field in Anchorage or by barge from the West Dock in Prudhoe Bay. During winter drilling activities, a tundra ice road is constructed near the Badami/Endicott Pipeline to tie-in to the Badami CPF pad. This winter tundra ice road is the only land connection to the Dalton Highway and the Badami Unit. Light passenger trucks, dump trucks, vacuum trucks, tractor trailers, fuel trucks, and heavy equipment (

e.g.,

large drill rigs, well simulation equipment) travel on this road during the winter season. This road also opens as an ADNR-permitted trail during off-years where Tuckers (a brand of tracked vehicle) or tracked Steigers (a brand of tractor) use it with sleds and snow machines. Activities related to this opening would be limited to necessary resupply and routine valve station maintenance along the oil sales pipeline corridor.

Flights from Anchorage land at Badami Airfield (N70.13747, W147.0304) for a total of 32 flight legs monthly. Additionally, Badami transports personnel and equipment from Deadhorse to Badami Airfield. Approximately 24 cargo flights land at Badami Airfield annually depending on Unit activities and urgency. Badami also conducts aerial pipeline inspections. These flights are typically flown by smaller, charter aircrafts at a minimum altitude of 305 m (1,000 ft) at ground level.

Tundra travel at Badami takes place during both the summer and winter season. Rolligons and Tuckers (off-road vehicles) are used during the summer for cargo and resupply activities but may also be used to access any pipelines and valve pads that are not located adjacent to the gravel roads. During periods of 24-hour sunlight, these vehicles may operate at any hour. Similar off-road vehicles are used during the winter season for maintenance and inspections. Temporary ice roads and ice pads may be built for the movement of heavy equipment to areas that are otherwise inaccessible for crucial maintenance and drilling. Ice road construction typically occurs in December or January; however, aside from the previously mentioned road connecting Badami to the Dalton Highway, ice roads are not routinely built for Badami. Roads are only built on an as-needed basis based on specific projects. Other activities performed during the winter season include pipeline inspections, culvert work, pigging, ground surveillance, geotechnical investigations, vertical support member (VSM) leveling, reconnaissance routes (along snow machine trails), and potentially spill response exercises. Road vehicles used include pickup trucks, vacuum trucks, loaders, box vans, excavators, and hot water trucks. Standard off-road vehicles include, but are not limited to, Tuckers, Rolligons, and snow machines.

On occasion, crew boats, landing craft, and barges may transport personnel and equipment from West Dock to Badami from July through September, pending the open-water window. Tugs and barges may also be used depending on operational needs. These trips typically go from Badami to other coastal Units, including Endicott and Point Thomson.

Badami performs emergency response and oil spill trainings during both open-water and ice-covered seasons. Smaller vessels (

i.e.,

zodiacs, aluminum work boats, air boats, and bay-class boats) typically participate in these exercises. Future classes may utilize other additional equipment or vessels as needed.

Currently, 10 wells have been drilled across the lifespan of the Badami Unit. Repair and maintenance activities on pipelines, culverts, ice roads, and pads are routine within the Badami Unit and occur year-round. Badami's current operator has received a permit from the U.S. Army Corps of Engineers to permit a new gravel pad (4.04 ha [10 ac]) located east of the Badami Barge Landing and a new gravel pit. This new pad would allow the drilling of seven more deployment wells at Badami. All new wells would be tied back to the CPF.

Duck Island Unit (Endicott)

Historically called the Endicott Oilfield, the Duck Island Unit is located approximately 16 km (10 mi) northeast of Prudhoe Bay. Currently, Hilcorp Alaska, LLC operates the oilfield. Endicott is the first offshore oilfield to continuously produce oil in the Arctic area of the United States and includes a variety of facilities, infrastructure, and islands. Endicott consists of 210 ha (522 ac) of land, 24 km (15 mi) of roads, 43 km (24 mi) of pipelines, two pads, and no gravel mine sites. The operations center and the processing center are situated on the 24-ha (58-ac) Main Production Island (MPI). To date, 113 wells have been drilled in efforts to develop the field, of which 73 still operate. Additionally, two satellite fields (Eider and Sag Delta North) are drilled from the Endicott MPI. Regular activities at Endicott consist of production and routine repair on the Endicott Sales Oil Pipeline, culverts, bridges, and bench bags. A significant repair on a bridge called the “Big Skookum” is expected to occur during the duration of this ITR.

Endicott's facilities are connected by gravel roads and are accessible through the Dalton Highway year-round via a variety of vehicles (pickup trucks, vacuum trucks, loaders, box vans, excavators, hot water trucks). Required equipment and supplies are brought in first from Anchorage and Fairbanks, through Deadhorse, and then into Endicott. Traffic is substantial, with heavy traffic on routes between processing facilities and camps. Conversely, drill site access routes experience much less traffic with standard visits occurring twice daily (within a 24-hour period). Traffic at drill sites increases during active drilling, maintenance, or other related projects and tends to subside during normal operations. Hilcorp uses a variety of vehicles on these roads, including light passenger trucks, heavy tractor-trailer trucks, heavy equipment, and very large drill rigs. Ice roads are only built on an as-needed basis for specific projects.

Air travel via helicopter from an established pad on Endicott to Deadhorse Airport is necessary only if the access bridges are washed out (typically mid to late May to the start of June). During such instances, approximately 20-30 crew flights would occur along with cargo flights about once a week. Hilcorp also performs

maternal polar bear den surveys via aircraft.

Hilcorp performs tundra travel work during the winter season (December-May; based on the tundra opening dates). Activities involving summer tundra travel are not routine, and pipeline inspections can be performed using established roads. During the winter season, off-road vehicles (

e.g.,

Tuckers, snow machines, or tracked utility vehicles called Argo centaurs) perform maintenance, pipeline inspections, culvert work, pigging, ground surveillance, VSM leveling, reconnaissance routes (snow machine trails), spill response exercises, and geotechnical investigations across Endicott.

Tugs and barges are used to transport fuel and cargo between Endicott, West Dock, Milne, and Northstar during the July to September period (pending the open-water period). Trips have been as many as over 80 or as few as 3 annually depending on the needs in the Unit, and since 2012, the number of trips between these fields has ranged from 6 to 30. However, a tug and barge have been historically used once a year to transport workover rigs between West Dock, Endicott, and Northstar. Endicott performs emergency response and oil spill trainings during both the open-water and ice-covered seasons. Smaller vessels (

i.e.,

zodiacs, Kiwi Noreens, bay-class boats) participate in these exercises; however, future classes may utilize other additional equipment or vessels (

e.g.,

the ARKTOS amphibious emergency escape vehicle) as needed. ARKTOS training will not be conducted during the summer.

Kuparuk River Unit

ConocoPhillips Alaska, Inc., operates facilities in the Kuparuk River Unit. This Unit is composed of several additional satellite oilfields (Tarn, Palm, Tabasco, West Sak, and Meltwater) containing 49 producing drill sites. Collectively, the Greater Kuparuk Area consists of approximately 1,013 ha (2,504 ac) made up of 209 km (130 mi) of gravel roads, 206 km (128 mi) of pipelines, 4 gravel mine sites, and over 73 gravel pads. A maximum of 1,200 personnel can be accommodated at the Kuparuk Operations Center and the Kuparuk Construction Camp. The camps at the Kuparuk Industrial Center are used to accommodate overflow personnel.

Kuparuk's facilities are all connected by gravel road and are accessible from the Dalton Highway year-round. ConocoPhillips utilizes a variety of vehicles on these roads, including light passenger trucks, heavy tractor-trailer trucks, heavy equipment, and very large drill rigs. Required equipment and supplies are flown in through Deadhorse and then transported via vehicle into the Kuparuk River Unit. Traffic has been noted to be substantial, with specific arterial routes between processing facilities and camps experiencing the heaviest use. Conversely, drill site access routes experience much less traffic with standard visits to drill sites occurring at least twice daily (within a 24-hour period). Traffic at drill sites increases during drilling activities, maintenance, or other related projects and tends to subside during normal operations.

The Kuparuk River Unit uses its own private runway (Kuparuk Airstrip; N70.330708, W149.597688). Crew and personnel are transported to Kuparuk on an average of two flights per day. Flights arrive into Kuparuk only on the weekdays (Monday through Friday). Year round, approximately 34 flights per week transport crew and personnel between Kuparuk and Alpine Airport. ConocoPhillips plans to replace the passenger flights from Alpine to Kuparuk in 2021 with direct flights to both Alpine and Kuparuk from Anchorage. These flights are expected to occur five times weekly and will replace the weekly flights from Alpine to Kuparuk. Cargo is also flown into Kuparuk on personnel flights. The single exception would be for special and specific flights when the Spine road is blocked. Occasionally, a helicopter will be used to transport personnel and equipment within the Kuparuk River Unit. These flights generally occur between mid-May and mid-September and account for an estimated 50 landings annually in Kuparuk. The location and duration of these flights are variable, and helicopters could land at the Kuparuk Airstrip or remote locations on the tundra. However, only 4 of the estimated 50 landings are within 3.2 km (5 mi) of the coast.

ConocoPhillips flies surveys of remote sections of the Kuparuk crude pipeline one to two times weekly during summer months as well as during winter months when there is reduced visibility from snow cover. During winter months, maternal den surveys are also performed using aircraft with mounted AIR cameras. Off-road vehicles (such as Rolligons and Tuckers) are used for maintenance and inspection of pipelines and power poles that are not located adjacent to the gravel roads. These vehicles operate near the road (152 m [500 ft]) and may operate for 24 hours a day during summer months. During winter months, temporary ice roads and pads are built to move heavy equipment to areas that may be inaccessible. Winter tundra travel distances average approximately 1,931 km (1,200 mi) with ice roads averaging approximately 17.7 km (11 mi) and may occur at any hour of the day. Dredging and screeding occur annually to the extent necessary for safety, continuation of seawater flow, and dock stability at the Kuparuk saltwater treatment plant intake and at Oliktok dock. Dredging occurs within a 1.5-ha (3.7-ac) area, and screeding occurs within a 1-ha (2.5-ac) area. Operations are conducted during the open-water season (May to October annually). Removed material from screeding and dredging is deposited in upland areas above the high tide, such as along the Oliktok causeway and saltwater treatment plant (STP) pad. ConocoPhillips removes approximately 0.6 to 1.1 m (2 to 3.5 ft) of sediment per year. Dredging activities typically last for 21 days, and screeding activities typically last 12 days annually. Boats are also used to perform routine maintenance as needed on the STP outfalls and inlets. ConocoPhillips infrequently has marine vessel traffic at the Oliktok Dock.

ConocoPhillips performs emergency response and oil spill trainings during both open-water and ice-covered seasons. Smaller vessels (

i.e.,

zodiacs, aluminum work boats, air boats, and bay-class boats) typically participate in these exercises. Future classes may utilize other additional equipment or vessels as needed.

The Willow Development Project, which is described in full in

Planned Activities at New Oil and Gas Facilities for 2021-2026,

would lead to increased activity through the Kuparuk River Unit. Prefabricated modules would be transported through the Unit. Module transportation involves an increase in road, aircraft, and vessel traffic resulting in the need for gravel road and gravel pad modifications, ice road and ice pad construction, and sea floor screeding. During the 2023 summer season, gravel hauling and placement to modify existing roads and pads used in support of the Willow Development would take place. An existing 12-acre gravel pad located 13.2 km (2 mi) south of the Oliktok Dock would require the addition of 33,411 cubic m (43,700 cubic yd) of gravel, increasing pad thickness to support the weight of the modules during staging. However, this addition of gravel would not impact the current footprint of the pad. Additionally, ConocoPhillips plans to widen six road curves and add four 0.2-ha (0.5-ac) pullouts between the Oliktok Dock and Drill Site 2P as well as increase the thickness of the 3.2-km (2-

mi) gravel road from the Oliktok Dock to the staging pad—requiring approximately 30,811 cubic m (40,300 yd) of gravel and resulting in an increase in footprint of the gravel road by <0.4 ha (<0.1 ac). Twelve culverts are estimated to be extended within this part of the gravel road to accommodate the additional thickness (approximately five culverts per mile). This would yield a new gravel footprint with an additional 2 ha (5.0 ac) and 90,752 cubic m (118,700 cubic yd). In 2025, a 6.1-ha (15-ac) ice pad, for camp placement, and an ice road for module transportation, would be constructed in association with the Willow Project. The planned location is near Drill Site 2P, over 32.2 km (20 mi) away from the coastline.

An increase in road traffic to Kuparuk is expected to begin in 2023 and continue into the summer of 2026. Activities would mostly consist of the transportation of freight, equipment, and support crews between Oliktok Point, the Kuparuk Airport, and the NPR-A. The number of weekly flights will also increase with an average of 6 additional weekly flights in 2023, 4 additional flights per week in 2024, 14 additional flights per week in 2025, and 4 additional flights per week in 2026. Eight barges would deliver the prefabricated modules and bulk material to Oliktok Dock using existing and regularly used marine transportation routes in the summer of 2024 and 2026.

Due to the current depths of water at the Oliktok Dock (2.4 m [8 ft]), lightering barges (barges that transfer cargo between vessels to reduce a vessel's draft) would be used to support the delivery of large modules to the Dock. The location of the lightering transfer would be approximately 3.7 km (2.3 mi) north of Oliktok Dock in 3.05 m (10 ft) of water. Screeding operations would occur during the summer open-water season 2022-2024 and 2026 starting mid-July and take approximately one week to complete. The activities would impact an area of 3.9 ha (9.6 ac) and an additional hectare (2.5 ac) in front of the Oliktok Dock to facilitate the unloading of the lightering barges. Bathymetry measurements would be taken after to confirm the appropriate conditions of the screeded seafloor surface.

Milne Point Unit

The Milne Point Unit is located 56 km (35 mi) northwest of Prudhoe Bay, producing from three main pools, including Kuparuk, Schrader Bluff, and Sag River. The total development area of Milne Point is 182 ha (450 ac), including 80 ha (198 ac) of 14 gravel pads, 54 km (33 mi) of gravel roads and mines, 161 km (100 mi) of pipelines, and over 330 wells.

Milne Point's facilities are connected by gravel roads and are accessible by the Dalton Highway year-round via a variety of vehicles (pickup trucks, vacuum trucks, loaders, box vans, excavators, hot water trucks). Required equipment and supplies are brought in first from Anchorage and Fairbanks, through Deadhorse, and then into the Milne Point Unit. Arterial roads between processing facilities and camps experience heavy traffic use. Conversely, drill site access routes experience much less traffic, with standard visits to drill sites occurring twice daily (within a 24-hour period). Traffic at drill sites increases during drilling activities, maintenance, or other related projects and tends to subside during normal operations. Industry uses a variety of vehicles on these roads, including light passenger trucks, heavy tractor-trailer trucks, heavy equipment, and very large drill rigs.

Air travel via helicopter from an established pad (N70.453268, W149.447530) to Deadhorse Airport is necessary only if the access bridges are washed out (typically mid to late May to the start of June). During such instances, approximately 20-30 crew flights would occur, along with cargo flights, about once a week. Hilcorp also performs maternal polar bear den surveys via aircraft.

Hilcorp uses off-road vehicles (Rolligons and Tuckers) for tundra travel during summer months to access any pipelines and power poles not found adjacent to the gravel roads. During the winter seasons, temporary ice roads and ice pads are built as needed across the Unit to move heavy equipment to areas otherwise inaccessible. Hilcorp also uses their off-road vehicles (Tuckers, snow machines, and Argo centaurs) during the winter to perform maintenance and inspections. Additionally, road vehicles (pickup trucks, vacuum trucks, loaders, box vans, excavators, and hot water trucks) are used to perform pipeline inspections, culvert work, pigging, ground surveillance, VSM leveling, reconnaissance routes (snow machine trails), potential spill response exercises, and geotechnical investigations.

There are 14 pads and 2 gravel mine sites within the Milne Point Unit. Twenty-eight new wells are expected to be drilled over the next 7 years. Repair activities are routine at Milne Point and occur on pipelines, culverts, ice roads, and pads. Hilcorp also has plans to continue development on Milne Point and will be running two to three more drilling rigs over the next 5 years—requiring several pad expansions to support them. Hilcorp plans to expand six pads, including: S Pad (4.5 ha [11 ac]), I Pad (0.81 ha [2 ac]), L Pad (0.81 ha [2 ac]), Moose Pad (0.81 ha [2 ac]), B Pad (2.1 ha [5.3 ac]), and E Pad (0.4 ha [1 ac]). Additionally, Hillcorp's proposed Raven Pad is projected to be built in 2021 between the L and F Pads. This pad will be 12.1 ha (30 ac) and contain various facilities, pipelines, tie-ins, a new pipeline/VSM along existing routes connecting F Pad to CFP and 45 wells.

Hilcorp is also planning to drill at least 28 new wells with a potential for more over the period of the ITR. New facilities will be installed for polymer injections, flowlines for new wells, pipelines, camps, tanks, and main facility improvements. This will require the development of new gravel pits for mining. Some of the new facilities planned to be built include: Upgrades to Moose pad; F Pad Polymer facility installation and startup; 2020 shutdown for A-Train process vessel inspections and upgrades; LM2500 turbine overhaul completion; Raven Pad design and civil work; S Pad facility future expansion; S Pad polymer engineering and procurement; diesel to slop oil tank conversion; and I Pad redevelopment. Repair activities will be routinely performed on pipelines, culverts, ice roads, and pads. Power generation and infrastructure at L Pad and polymer injection facilities are also planned on Moose Pad, F Pad, J Pad, and L Pad.

Hilcorp plans to expand the size of the Milne mine site up to 9 ha (22.37 ac). Approximately 6.3 ha (15.15 ac) will be mined for gravel. Overburden store will require about 1 ha (2.5 ac) and will be surrounded by a 1.3-ha (3.4-ac) buffer. Around 0.5 ha (1.32 ac) will be used to expand the Dalton Highway. The Ugnu Mine Site E, located approximately 8 km (5 mi) southeast of Oliktok Point and 3.2 km (2 mi) south of Simpson Lagoon, will also be expanded during the 2021-2026 ITR. Hilcorp's planned expansion for the new cell is approximately 259 m long by 274 m wide (850 ft long by 900 ft wide) or 7.1 ha (17.56 ac). This would produce an estimated 434,267 cubic m (568,000 cubic yd) of overburden including a 20 percent swell factor, and approximately 764,554 cubic m (1,000,000 cubic yd) of gravel. The footprint of the Phase I Material Site is expected to be 6.5 ha (16 ac). Overburden storage, a thermal barrier, and access road would require approximately 4.2 ha (10.3 ac). The final site layout will be dependent on gravel needs.

Marine vessels (specifically crew boats) are used to transport workers from West Dock to Milne Point if bridges are washed out. Additionally, vessels (tugs/barges) are used to transport fuel and cargo between Endicott, West Dock, Milne Point, and Northstar from July to September. While the frequency of these trips is dependent on operational needs in a given year, they are typically sparse. Hilcorp performs several emergency response and oil spill trainings throughout the year during both the open-water and ice-covered season. Smaller vessels (

i.e.,

zodiacs, Kiwi Noreens, bay-class boats) typically participate in these exercises; however, future classes may utilize other additional equipment or vessels (

e.g.,

the ARKTOS amphibious emergency escape vehicle) as needed. ARKTOS training will not be conducted during the summer, though Hilcorp notes that some variation in activities and equipment can be expected.

Nikaitchuq Unit

Eni U.S. Operating Co., Inc., is the 100 percent working interest owner and operator of the Nikaitchuq Unit. The Nikaitchuq Unit includes the following infrastructure: Oliktok Production Pad (OPP), Spy Island Drill site (SID), Nikaitchuq Operations Center (NOC), a subsea pipeline bundle, an onshore crude oil transmission pipeline (COTP), and an onshore pad that ties into the Kuparuk Pipeline (known as KPP). Currently, the SID includes 19 production wells, one exploration well on a Federal offshore lease, 14 injection wells, one Class-1 disposal well, and two shallow water wells. The OPP includes 12 production wells, 8 injection wells, 3 source water wells, 1 Class-1 disposal well, and 2 shallow water wells.

Road access in the Nikaichuq Unit for the OPP, NOC, and KPP are through connected gravel roads from the Dalton Highway year-round and maintained by Kuparuk. Equipment and cargo are brought in from Anchorage and Fairbanks after a stopover in Deadhorse. Traffic levels vary depending on ongoing activities but do not change significantly with time of year.

Crew and cargo are primarily transported using commercial flights to Deadhorse and then by vehicle. A helicopter may be used for transportation of personnel, the delivery and movement of supplies and equipment from Deadhorse when the Kuparuk Bridge is unavailable, or in the event of a medical emergency; however, these flights are infrequent. Eni utilizes off-road vehicles (Rolligons and other track vehicles) for both the summer and winter seasons for tundra travel; however, tundra travel is infrequent. Primarily, these activities would occur when access to the COTP between OPP and KPP is being inspected or under maintenance. Eni utilizes off-road vehicles during winter to conduct maintenance and inspections on COTP and to transport personnel, equipment, and supplies between the OPP and SID during periods where a sea ice road between the two locations is being constructed. Until the sea ice road is completed, vehicles travel by a single snow trail (approximately 6.8 km [4.25 mi]).

Two to three ice roads are constructed within the Nikaichuq Unit annually. These ice roads are typically around 6.8 km (4.25 mi) long and 18.3 m (60 ft) wide. Traffic occurs at all hours, consisting of a variety of light vehicles, such as pickup trucks and sport-utility vehicles (SUVs), high-capacity personnel transport vehicles (busses), ice road construction equipment (road graders, water tankers, snow blowers, front end loaders, and dump trucks), vacuum trucks, and tractor trailers. To build the sea ice road, Eni harvests ice chips from Lake K-304 after constructing a 0.3-km (0.2-mi) long, 9.1-m (30-ft) wide tundra ice road. In the past, a short tundra ice road was also constructed and used to access a lake to obtain water for maintenance of a sea ice road, and such an ice road may be used in the future.

Maintenance activities, such as gravel and gravel bag placement along the subsea pipeline, may occur as needed. Routine screeding is generally performed near barge landings at OPP and SID. Dredging is also possible in this area, although not likely. Hovercrafts are used to transport both cargo and personnel year round but generally occur daily between Oliktok Point and SID during October through January and May through July. Crew boats with passengers, tugs, and barges are used to transport cargo from Oliktok Point to the SID daily during open-water months (July through September) as needed. Eni also performs emergency response and oil spill trainings during both open-water and ice seasons.

Northstar Unit

The Northstar Unit is made up of a 15,360-ha (38,400-ac) reservoir, and Hilcorp Alaska, Inc., currently operates it. Northstar is an artificial island located approximately 6 km (4 mi) northwest of Point McIntyer and 10 km (6 mi) from Prudhoe Bay. The water depth surrounding the island is approximately 11.9 m (39 ft) deep. Thirty wells have been drilled to develop Northstar, of which 23 are still operable. A buried subsea pipeline (58 km [36 mi] long) connects the facilities from Northstar to the Prudhoe Bay oilfield. Access to the island is through helicopter, hovercraft, boat, Tucker, and vehicle (only during the winter ice road season). Routine activities include maintenance and bench/block repairs on culvert, road, and pipelines.

There are no established roads on Northstar Island. Loaders, cranes, and a telescopic material handler are used to move cargo and equipment. Hilcorp exclusively uses helicopters for all aircraft operations around the Northstar Unit, with an estimated 800 landings per year. Crew and cargo flights travel daily from May to January to Northstar Island from Deadhorse Airport. Sling-loading equipment and supplies may also occur from May through December. Pipeline inspections via aircraft are performed once weekly—generally with no landings. However, once per quarter, the helicopter lands to inspect the end of the pipeline where it enters the water (N70.404220, W148.692130).

Only winter tundra travel occurs at Northstar. Hilcorp typically builds several unimproved ice trails to Northstar, including a trail along the pipeline corridor from the valve pad near the Dew Line site to Northstar (9.5 km [5.93 mi]); a trail from West Dock to the pipeline shore crossing, grounded ice along the coastline (7.8 km [4.82 mi]); two unimproved ice road paths from the hovercraft tent at the dockhead; one trail under the West Dock Causeway (WDC) bridge to well pad DH3 (1.4 km [0.86 mi]); and a trail around West Dock to intersect the main ice road north of the STP (4.6 km [2.85 mi]). Hilcorp may also construct any number of shorter trails into undisturbed areas to avoid unstable/unsafe areas throughout the ice season. These detours may be constructed after March 1st due to safety considerations and may deviate approximately 23-46 m (75-150 ft) from the original road or trail.

Hilcorp typically constructs an approximately 11.7-km (7.3-mi) long ice road each year between Northstar and Prudhoe Bay (specifically West Dock) to allow for the transportation of personnel, equipment, materials, and supplies. This ice road generally allows standard vehicles (SUVs, pickup trucks, buses, other trucks) to transport crew and equipment to and from the island; however, Hilcorp may elect to construct an ice trail that supports only light-weight vehicles depending on operational needs and weather conditions.

During December or January before ice roads are built, Tucker tracked vehicles transport cargo and crew daily. During ice road construction, work will occur for 24 hours a day, 7 days a week, and is stopped only when unsafe conditions are presented (

e.g.,

high winds, extremely low temperatures). Ice road construction typically begins around January 1st when the ice is considered thick enough (minimum of 61 cm [24 in]) and is typically completed within 45 days of the start date.

Once the ice road is built, tractor-trailer trucks transport freight, chemicals for resupplies (occurs every 2 weeks using 10 truckloads), diesel, and other equipment. Additional personnel and smaller freight travel multiple times a day in light passenger traffic buses and pickup trucks. A grader and snow blower maintain the ice road daily, and in the event of cracks in the ice road, a loader may be used. Tucker tracked vehicles and hovercraft are used beginning mid-May as ice becomes unstable, then, as weather warms, boats and helicopters are used. Hilcorp uses hovercraft daily between West Dock and Northstar Island to transport crew and cargo (October through January and May through July) when broken-ice conditions are present. Crew boats have also been used to carry crew and cargo daily from West Dock to Northstar Island during open-water months (July to September) when hovercraft are not in use. Tugs and barges transport fuel and cargo from West Dock and Endicott to Northstar Island during the open-water season (July through September) and may be used once a year to transport workover rigs. There are typically 6-30 trips per year.

Northstar performs emergency response and oil spill trainings during both open-water and ice-covered seasons. Smaller vessels (

i.e.,

zodiacs, aluminum work boats, air boats, and bay-class boats) typically participate in these exercises. Future classes may utilize other additional equipment or vessels (

e.g.,

the ARKTOS amphibious emergency escape vehicle) as needed. However, the ARKTOS training will not be conducted during the summer.

Oooguruk Unit

The Oooguruk Unit was originally developed in 2008 and is operated by Eni, consisting of several developments and facilities including the Oooguruk Drill site (ODS), a 13-km (8.1-mi) long pipeline bundle, and the Oooguruk Tie-in Pad (OTP). The OTP is an onshore production facility that consists of tanks, flowlines, support infrastructure, and power generation facilities. The pipeline bundle consists of two oil pipelines, a 30.5-cm (12-in) inner diameter production flowline, and a 5.1-cm (2-in) inner diameter diesel/base oil flowline. The bundle sits about 61 m (200 ft) from the shoreline when onshore and runs about 3.8 km (2.4 mi) on vertical supports to the OTP. A 30.5-cm (12-in) product sales line enters a metering skid on the southeast side of the OTP. This metering skid represents the point where the custody of the oil is transferred to ConocoPhillips Alaska, Inc. Diesel fuels and base oil are stored at the OTP to resupply the ODS as needed.

The ODS is a manmade island located approximately 9.2 km (5.7 mi) offshore and measuring approximately 5.7 ha (14 ac) and is found approximately 12.9 km (8 mi) northwest of the OTP. The site includes living quarters with 150 beds, a helicopter landing site, various production and injection wells, and a grind and inject facility. A Nabors rig is also located on the pad and the rig is currently not in use. The ocean surrounding the island is about 3.05 m (10 ft) in depth and considered relatively shallow.

Oooguruk relies on interconnected gravel roads maintained by Kuparuk to gain access to the Dalton Highway throughout the year. Equipment and supplies travel from Anchorage and Fairbanks to the OTP through Deadhorse. The ODS is connected to the road system only when an ice road is developed and available from February to May.

Eni uses helicopters from May to January for cargo transport, which is limited to flights between the OTP and the ODS. Work personnel depart from the Nikaitchuq Unit's NOC pad; Eni estimates about 700 flights occur during the helicopter season for both crew and field personnel.

Eni occasionally utilizes off-road vehicles (

e.g.,

Rolligons and track vehicles) during the summer tundra months with activities limited to cleanup on ice roads or required maintenance of the pipeline bundle. During winter months, track vehicles transport personnel, equipment, and supplies between the OTP and ODS during the ice road construction period. The ice road is approximately 9.8-m (32-ft) wide, and traffic and activity are constant—most notably from light vehicles (pickup trucks, SUVs), high-capacity personnel transport (buses), ice road construction equipment (road graders, water tankers, snow blowers, front-end loaders, dump trucks), and well maintenance equipment (coil tubing units, wire-line units, hot oil trucks). Eni estimates over 3,500 roundtrips occur annually.

Eni will add 2,294 cubic m (3,000 cubic yd) of gravel to facilitate a hovercraft landing zone on island east and will also conduct additional gravel maintenance at the “shoreline crossing” of the pipeline or the area where the pipeline transitions from the above-ground section to the subsea pipeline. Maintenance in these areas is necessary to replace gravel lost to erosion from ocean wave action. Additionally, Eni performs gravel placement on the subsea pipeline to offset strudel scour—pending the results of annual surveys. Island “armor” (

i.e.,

gravel bags) requires maintenance throughout the year as well.

Eni utilizes some in-water vessel traffic to transport crew and cargo from Oliktok Point to the ODS during the open-water season (typically July to September). These trips occur daily (or less if hovercraft are used). Additionally, Eni uses tugs and barges to transport cargo from Oliktok Point to the ODS from July to September. These vessels make varying amounts of trips, from a few trips annually up to 50 trips depending on operational needs at the time.

Like the trainings performed at the Nikaitchuq Unit, Eni would also conduct emergency and oil spill response trainings throughout the ITR period at various times. Trainings will be conducted during both open-water and ice-covered seasons with training exercises occurring on both the land and the water depending on current ice conditions. Further information on these trainings can be found on the submitted AOGA Request for 2021-2026.

Point Thomson Unit

The Point Thomson Unit (PTU) is located approximately 32 km (20 mi) east of the Badami field and 96 km (60 mi) east of Deadhorse and is operated by ExxonMobil. The Unit includes the Point Thomson initial production system (IPS), Sourdough Wells, and legacy exploration sites (

i.e.,

PTU 1-4, Alaska C-1, West Staines State 2 and 18-9-23). The total Point Thomson IPS area is approximately 91 ha (225 ac), including 12.4 km (7.7 mi) of gravel roads, 35 km (22 mi) of pipelines, one gravel mine site, and three gravel pads (Central, West, and C-1).

The Point Thomson IPS facilities are interconnected by gravel roads but are not connected to other oilfields or developments. Equipment and supplies are brought in via air, barge, ice road, or tundra travel primarily from Deadhorse. Traffic on gravel roads within the PTU

occurs daily with roads from Central Pad to the airstrip experiencing the heaviest use. This consistent heavy use is not influenced by time of year. Vehicle types include light passenger trucks/vans, heavy tractor-trailer trucks, and heavy equipment usage on pads, particularly for snow removal and dust control.

Personnel and most cargo are transported to Point Thomson using aircraft departing from Deadhorse. During normal operations, an average of two to four passenger flights per week land at the Point Thomson Airport. Typically, there are 12 cargo flights per year (or one per month) that may land at Point Thomson, but frequency is reduced January to April when tundra is open. Aerial pipeline inspection surveys are conducted weekly, and environmental surveys and operations typically occur for one to two weeks each summer. The environmental surveys are generally performed at remediation sites such as West Staines State 2 and 18-9-23, areas of pipeline maintenance, and tundra travel routes.

Off-road vehicles (

e.g.,

Rolligons and track vehicles) are only used during the summer tundra months for emergency purposes such as accessing the pipeline. During winter months, off-road vehicles provide access to spill response conexes, deliver cargo supplies from Deadhorse, and maintain and inspect the PTU. Tundra travel includes a route south of the pipeline from Deadhorse to Point Thomson, a route along the pipeline right-of-way (ROW), spur roads as needed between the southern route and the pipeline ROW, and a route to spill conexes totaling approximately 146.5 km (91 mi). Travel along these routes can occur at any time of day.

Temporary ice roads and pads near the Point Thomson Facility are built to move heavy equipment to areas otherwise inaccessible for maintenance and construction activities. Ice road and ice pad construction typically begins in December or January. An ice road to Point Thomson is typically needed in the event that a drilling rig needs to be mobilized and extends east from the Endicott Road, connects to the Badami facilities, and continues east along the coast to Point Thomson.

Barging usually occurs from mid-July through September. In the event additional barging operations are needed, dredging and screeding activities may occur to allow barges to dock at Point Thomson. If dredging and screeding activities are necessary, the work would take place during the open-water season and would last less than a week. ExxonMobil also performs emergency response and oil spill trainings during the summer season. On occasion, spill response boats are used to transport operations and maintenance personnel to Badami for pipeline maintenance.

Expansion activities are expected to occur over 4 years and would consist of new facilities and new wells on the Central Pad to increase gas and condensate production. The Central Pad would require a minor expansion of only 2.8 ha (7 ac) to the southwest. Minor size increases on infield pipelines will also occur, but the facility footprint would not otherwise increase. To support this project, an annual ice road would be constructed, and summer barging activities would occur to transport a drilling rig, additional construction camps, field personnel, fuel, equipment, and other supplies or materials. Gravel would be sourced from an existing stockpile, supplemented by additional gravel volume that would be sourced offsite as necessary. Drilling of wells is expected to occur during the later years of construction, and new modular production facilities would be fabricated offsite and then delivered via sealift.

A small number of barge trips (<10 annually) are expected to deliver equipment, fuel, and supplies during the open-water season (mid-July through September) from Deadhorse and may occur at any time of day. Additional development activities are planned within PTU and are described in the section

Alaska Liquefied Natural Gas Project (Alaska LNG).

Prudhoe Bay Unit

The Prudhoe Bay Unit (PBU) is the largest producing oilfield in North America and is operated by Hilcorp. The PBU includes satellite oilfields Aurora, Borealis, Midnight Sun, Polaris, and Orion. The total development area is approximately 1,778 ha (4,392 ac), including 450 km (280 mi) of gravel roads, 2,543 km (1,580 mi) of pipelines, 4 gravel mines, and over 113 gravel pads. Camp facilities such as the Prudhoe Bay Operations Center, Main Construction Camp, Base Operations Center, and Tarmac camp are also within the PBU.

PBU facilities are connected by gravel roads and can be accessed from the Dalton Highway year-round. Equipment and supplies are flown or transported over land from Anchorage and Fairbanks to Deadhorse before they are taken to the PBU over land. Traffic is constant across the PBU with arterial routes between processing facilities and camps experiencing the heaviest use while drill site access roads are traveled far less except during active drilling, maintenance, or other projects. Traffic is not influenced by the time of year. Vehicle types include light passenger trucks, heavy tractor-trailer trucks, heavy equipment, and very large drill rigs.

Personnel and cargo are transported to the PBU on regularly scheduled, commercial passenger flights through Deadhorse and then transported to camp assignments via bus. Pipeline surveys are flown every 7 days departing from CPAI's Alpine airstrip beginning the flight route at Pump Station 1 and covering a variety of routes in and around the Gathering Center 2, Flow Station 2, Central Compressor Pad, West Gas Injection, and East Sag facilities. Pipelines are also surveyed once per day from the road system using a truck-mounted forward-looking infrared camera system. Various environmental studies are also conducted using aircraft. Surveys include polar bear den detection and tundra rehabilitation and revegetation studies. Tundra environmental studies occur annually each summer in July and August with field personnel being transported to sites over an average of 4 days. Flights take off and return to Deadhorse airport, and field landings include seven tundra sites an average of 25.7 km (16 mi) from Deadhorse airport. Only four of the seven tundra landing sites are within 8 km (5 mi) of the Beaufort coast. Unmanned aerial systems (UAS) are used for subsidence, flare, stack, and facility inspections from June to September as well as annual flood surveillance in the spring. UAS depart and arrive at the same location and only fly over roads, pipeline ROWs, and/or within 1.6 km (1 mi) or line of sight of the pad.

Off-road vehicles (such as Rolligons and Tuckers) are used for maintenance and inspection activities during the summer to access pipelines and/or power poles that are not located adjacent to the gravel roads. These vehicles typically operate near the road (152 m [500 ft]) and may operate for 24 hours a day during summer months. During winter months, temporary ice roads and pads are built to move heavy equipment to areas that may be inaccessible. Winter tundra travel distances and cumulative ice road lengths average about 120.7 and 12.1 km (75 and 7.5 mi), respectively, and may occur at any hour of the day. An additional 0.8 ha (2 ac) of ice pads are constructed each winter.

West Dock is the primary marine gateway to the greater Prudhoe Bay area with users including Industry vessels, cargo ships, oil spill responders, subsistence users, and to a lesser degree,

public and commercial vessels. Routine annual maintenance dredging of the seafloor around the WDC occurs to maintain navigational access to DH2 and DH3 and to insure continued intake of seawater to the existing STP. Approximately 15,291 cubic m (20,000 cubic yd) of material is anticipated to be dredged over 56.6 ha (140 ac); however, up to 172,024 cubic m (225,000 cubic yd) of material is authorized to be removed in a single year. All dredged material is placed as fill on the WDC for beach replenishment and erosion protection. Some sediments are moved but remain on the seafloor as part of the screeding process. Much of the dredging work takes place during the open-water season between May and October and will be completed in less than 30 working days. Annual installation and floats, moorings, and buoys are installed at the beginning of the open-water season and are removed at the end of the open-water season. Up to three buoys may be installed to each side of the breach (up to six buoys total).

During the 2021-2022 winter tundra travel period, an additional 8-km (5-mi) ice road, 0.8-ha (2-ac) ice pad, up to 8-km (5-mi) pipeline, and pad space are expected to be constructed to support I-Pad expansion totaling 12.1 ha (30 ac) for the ice road and ice pad and 8.5 ha (21 ac) for the pad space, pipeline, and VSM footprints. Other pad expansions include approximately 0.8 ha (2 ac) per year 2021-2026 at DS3-DS0 and P-Pad.

Additionally, the construction of up to a 56.7-ha (140-ac) mine site is expected. Construction will occur on a need-based, phased approach over 40 years with no more than 24.3 ha (60 ac) of gravel developed by 2026. A 4.3-km (2.7-mi) long and 24.4-m (80-ft) wide gravel access road will also be built for a total impacted area of 10.5 ha (26 ac) over 1 year.

Trans-Alaska Pipeline System (TAPS)

TAPS is a 122-cm (48-in) diameter crude oil transportation pipeline system that extends 1,287 km (800 mi) from Pump Station 1 in Prudhoe Bay Oilfield to the Valdez Marine Terminal. The lands occupied by TAPS are State-owned, and the ROWs are leased through April 2034. Alyeska Pipeline Service Company operates the pipeline ROW. Approximately 37 km (23 mi) of pipeline are located within 40 km (25 mi) of the Beaufort Sea coastline. A 238-km (148-mi) natural gas line that extends from Pump Station 1 provides support for pipeline operations and facilities. The TAPS mainline pipe ROW includes a gravel work pad and drive lane that crosses the Dalton Highway approximately 29 km (18 mi) south of Pump Station 1.

Travel primarily occurs along established rounds, four pipeline access roads, or along the pipeline ROW work pad. Ground-based surveillance on the TAPS ROW occurs once per week throughout the year. Equipment and supplies are transported via commercial carriers on the Dalton Highway. In the summer, travel is primarily restricted to the gravel work pad and access roads. There are occasional crossings of unvegetated gravel bars to repair remote flood control structures on the Sagavanirktok River. Transport of small-volume gravel material from the active river floodplain to the TAPS work pad may occur. Vehicles used during the summer include typical highway vehicles, maintenance equipment, and off-road trucks for gravel material transport. In the winter, travel occurs in similar areas compared to summer in addition to maintenance activities, such as subsurface pipeline excavations. Short (<0.4 km, <0.25 mi) temporary ice roads and ice pads are built to move heavy equipment when necessary. Vehicles used during the winter include off-road tracked vehicles so that snow plowing on the ROW is not required. The amount of traffic is generally not influenced by the time of year.

The Deadhorse Airport is the primary hub used for personnel transport and airfreight to TAPS facilities in the northern pipeline area. Commercial and charter flights are used for personnel transport, and crew change-outs generally occur every 2 weeks. Other aviation activities include pipeline surveillance, oil spill exercise/training/response, and seasonal hydrology observations. Aerial surveillance of the pipeline occurs once each week during daylight hours throughout the year. Approximately 50 hours per year are flown within 40 km (25 mi) of the Beaufort Sea coastline.

No TAPS-related in-water activities occur in the Beaufort Sea. Instead, these activities will be limited to the Sagavanirktok River and its tributaries. In-water construction and dredging may take place occasionally, and they are generally associated with flood control structures and repairs to culverts, low water crossings, and eroded work pads. Gravel mining may also occur on dry unvegetated bars of the active floodplain or in established gravel pits. On river bars, up to a 0.9-m (3-ft) deep layer of alluvial gravel is removed when the river is low, and this layer is allowed to naturally replenish. Additional construction of flood structures may be needed to address changes in the hydrology of the Sagavanirktok River and its tributaries during the 2021-2026 period.

Western North Slope—Colville River and Greater Mooses Tooth Units

The Western North Slope (WNS) consists of the CPAI's Alpine and Alpine satellite operations in the Colville River Unit (CRU) and the Greater Mooses Tooth Unit (GMTU). The Alpine reservoir covers 50,264 ha (124,204 ac), but the total developed area is approximately 153 ha (378 ac), which contains 45 km (28 mi) of gravel roads, 51.5 km (32 mi) of pipelines, and 14 gravel pads. The CRU has a combined production pad/drill site and four additional drill sites. The GMTU contains one producing drill site and a second drill site undergoing construction. Roads and pads are generally constructed during winter.

There are no permanent roads connecting WNS to industrial hubs or other oilfields. Gravel roads connect four of the five CRU drill sites. An ice road is constructed each winter to connect to the fifth CRU drill site. Gravel roads also connect the GMTU drill sites to the CRU, and gravel roads connect the two GMTU drill sites to each other. Each drill site with gravel road access is visited at least twice during a 24-hour period, depending on the weather. Drill site traffic levels increase during active drilling, maintenance, or other projects. Vehicles that use the gravel roads include light passenger trucks, heavy tractor-trailer trucks, heavy equipment, and very large drill rigs. The amount of traffic is generally not influenced by the time of year, but there may be increased amounts of traffic during the exploration season.

In the winter, off-road vehicles are used to access equipment for maintenance and inspections. Temporary ice roads and ice pads are built to move heavy equipment for maintenance and construction activities. An ice road is constructed to connect WNS to the Kuparuk oilfield (KRU) to move supplies for the rest of the year. More than 1,500 truckloads of modules, pipeline, and equipment are moved to WNS over this ice road, which is approximately 105 km (65 mi) in length. As mentioned previously, an ice road is constructed each winter to connect one of the CRU drill sites to the other CRU facilities in order to facilitate maintenance, drilling, and operations at this drill site. WNS ice roads typically operate from mid-January until late-April.

The Alpine Airstrip is a private runway that is used to transport personnel and cargo. An average of 60

to 80 personnel flights to/from the Alpine Airstrip occur each week. Within the CRU, the Alpine Airport transports personnel and supplies to and from the CRU drill site that is only connected by an ice road during the winter. There are approximately 700 cargo flights into Alpine each year. Cargo flight activity varies throughout the year with October through December being the busiest months. Aerial visual surveillance of the Alpine crude pipeline is conducted weekly for sections of the pipeline that are not accessible either by road or during winter months. These aerial surveillance inspections generally occur one to two times each week, and they average between two and four total flight hours each week. CPAI also uses aircraft to conduct environmental studies, including polar den detection surveys in the winter and caribou and bird surveys in the summer. These environmental surveys cover approximately 1,287 linear km (800 linear mi) over the CRU each year. In the summer from mid-May to mid-September, CPAI uses helicopters to transport personnel and equipment within the CRU (approximately 2,000 flights) and GMTU (approximately 650 flights).

There are no offshore or coastal facilities in the CRU. However, there are multiple bridges in the CRU and GMTU that required pilings which were driven into stream/riverbeds during construction. In-water activities may occur during emergency and oil spill response training exercises. During the ice-covered periods, training exercises may involve using equipment to detect, contain, and recover oil on and under ice. During the open-water season, air boats, shallow-draft jet boats and possibly other vessels may be used in the Nigliq Channel, the Colville River Main Channel, and other channels and tributaries connected to the Colville River. Vessels may occasionally enter the nearshore Beaufort Sea to transit between channels and/or tributaries of the Colville River Delta.

In the 2021-2026 period, two 4-ha (10-ac) multiseason ice pads would be located in the WNS in order to support the Willow Development construction in the NPR-A. Possible expansion activities for this period may include small pad expansions or new pads (<6.1 ha (15 ac)) to accommodate additional drilling and development of small pads and gravel roads to accommodate additional facilities and operational needs. Two gravel mine sources in the Tiŋmiaqsiuġvik area have been permitted to supply gravel for the Willow Development. The new gravel source would be accessed seasonally by an ice road. Increases in the amount of traffic within WNS are expected from 2023 to 2026. The increase in traffic is due to the transport of freight, equipment, and support crew between the Willow Development, the Oliktok Dock, and the Kuparuk Airport. The planned Willow Development is projected to add several flights to/from the Alpine Airstrip from 2021 to 2026. It is estimated that the number of annual flights may increase by a range of 49 to 122 flights. There are plans to replace passenger flights connecting Alpine and Kuparuk oilfields in 2021 with direct flights to these oilfields. This change would reduce the number of connector flights between these oilfields from 18 flights to 5 flights each week.

Planned Activities at New Oil and Gas Facilities for 2021-2026

AOGA's Request includes several new oil and gas facilities being planned for leases obtained by Industry (see the section about

Lease Sales

) in which development and exploration activities would occur. The information discussed below was provided by AOGA and is the best available information at the time AOGA's Request was finalized.

Bear Tooth Unit (Willow)

Located 45.1 km (28 mi) from Alpine, the Willow Development is currently owned and operated by ConocoPhillips Alaska, Inc. Willow is found in the Bear Tooth Unit (BTU) located within the northeastern area of the NPR-A. Discovered in 2016 after the drilling of the Tiŋmiaq 2 and 6 wells, Willow is estimated to contain 400-750 million barrels of oil and has the potential to produce over 100,000 barrels of oil per day. The Willow Project would require the development of several different types of infrastructure, including gravel roads, airstrips, ice roads, and ice pads, that would benefit seismic surveys, drilling, operations, production, pile-driving, dredging, and construction.

ConocoPhillips plans to develop the hydrocarbon resources within the BTU during the 2021-2026 timeline under this ITR. The proposed development at Willow would consist of five drill sites along with associated infrastructure, including flowlines, a CPF, a personnel camp, an airstrip, a sales oil pipeline, and various roads across the area. Additionally, Willow would require the development of a new gravel mine site and would use sea lifts for large modules at Oliktok Dock requiring transportation over gravel and ice roads in the winter.

Access to the Willow Development project area to Alpine, Kuparuk, or Deadhorse would be available by ground transportation along ice roads. Additionally, access to the Alpine Unit would occur by gravel road. The Development Plan requires 61.5 km (38.2 mi) of gravel road and seven bridges to connect the five drill sites to the Greater Mooses Tooth 2 (GMT2). The Willow Development would also require approximately 59.7 km (37.1 mi) or 104 ha (257.2 ac) of gravel roads to the Willow Central Processing Facility (WCF), the WCF to the Greater Mooses Tooth 2 (GMT2), to water sources, and to airstrip access roads. The gravel needed for any gravel-based development would be mined from a newly developed gravel mine site and then placed for the appropriate infrastructure during winter for the first 3 to 4 years of the construction.

Gravel mining and placement would occur almost exclusively in the winter season. Prepacked snow and ice road construction will be developed to access the gravel mine site, the gravel road, and pad locations in December and January yearly from 2021 to 2024, and again in 2026. Ice roads would be available for use by February 1 annually. The Willow plan would require gravel for several facilities, including Bear Tooth 1 (BT1), Bear Tooth 2 (BT2), Bear Tooth 3 (BT3), Bear Tooth 4 (BT4), roads, WCF, Willow Operations Center (WOC), and the airstrip. Additionally, an all-season gravel road would be present from the GMT2 development and extend southwest towards the Willow Development area. This access road would end at BT3, located west from the WCF, WOC, and the airstrip. More gravel roads are planned to extend to the north, connecting BT1, BT2, and BT4. An infield road at BT3 would provide a water-source access road that would extend to the east to a freshwater reservoir access pad and water intake system developed by ConocoPhillips. Further east from the planned airstrip, an infield road is planned to extend north to BT1, continue north to BT2, and end at BT4. This road would intersect Judy (Iqalliqpik) Creek and Fish (Uvlutuuq) Creek at several points. Culvert locations would be identified and installed during the first construction season prior to breakup. Gravel pads would be developed before on-pad facilities are constructed. Gravel conditions and re-compaction would occur later in the year.

The Willow area is expected to have year-round aircraft operations and access from the Alpine Unit, Kuparuk Unit, Deadhorse, Anchorage, Fairbanks, and several other locations. Aircraft would primarily be used for support activities and transporting workers,

materials, equipment, and waste from the Willow Development to Fairbanks, Anchorage, Kuparuk, and Deadhorse. To support these operations, a 1,890-m (6,200-ft)-long gravel airstrip would be developed and is expected to be located near the WOC. Aircraft flight paths would be directed to the north of Nuiqsut. The construction for the airstrip is expected to begin during the 2021 winter season and completed by the summer of 2022. Before its completion, ConocoPhillips would utilize the airstrip at the Colville Delta 1 at the Alpine CPF. After completion of the airstrip, helicopters would be used to support various projects within the Willow Development starting in 2023. An estimated 82 helicopter flights would occur annually during 2023-2026 between April and August. After the development of planned gravel roads and during activities such as drilling and related operations, helicopters would be limited to support environmental monitoring and spill response support. ConocoPhillips estimates that 50 helicopter trips to and from Alpine would occur in 2021, and 25 helicopter trips would occur from Alpine in 2022.

ConocoPhillips plans to develop and utilize ice roads to support gravel infrastructure and pipeline construction to access lakes and gravel sources and use separate ice roads for construction and general traffic due to safety considerations regarding traffic frequency and equipment size. The ice road used to travel to the Willow Development is estimated to be shorter in length than previously built ice roads at Kuparuk and Alpine, and ConocoPhillips expects the ice road use season at Willow to be approximately 90 days, from January 25 to April 25. In the winter ice road season (February through April), material resupply and waste would be transported to Kuparuk and to the rest of the North Slope gravel road system via the annual Alpine Resupply Ice Road. Additionally, during drilling and operations, there would be seasonal ground access from Willow to Deadhorse and Kuparuk from the annually constructed Alpine Resupply Ice Road and then to the Alpine and GMT gravel roads.

Seasonal ice roads would be developed and used during construction at Willow's gravel mine, bridge crossings, horizontal directional drilling crossing, and other locations as needed. A 4-ha (10-ac) multiseason ice pad would be developed and used throughout construction. This ice pad would be constructed near the WOC from 2021 to 2022 and rotated on an annual basis.

Pipelines for the Willow Development would be installed during the winter season from ice roads. Following VSMs and horizontal support members (HSMs) assembly and installation; pipelines would be placed, welded, tested, and installed on pipe saddles on top of the HSMs. ConocoPhillips expects that the Colville River horizontal directional drilling pipeline crossing would be completed during the 2022 winter season. Pipeline installation would take approximately 1 to 3 years per pipeline, depending on several parameters such as pipeline length and location.

In 2024 at BT1, a drill rig would be mobilized, and drilling would begin prior to the WCF and drill site facilities being completed. ConocoPhillips estimates about 18 to 24 months of “pre-drilling” activities to occur, allowing the WCF to be commissioned immediately after its construction. Wells would be drilled consecutively from BT1, BT3, and BT2; however, the timing and order is based upon drill rig availability and economic decisionmaking. A second drilling rig may be utilized during the drilling phase of the Willow Development as well. ConocoPhillips estimates that drilling would occur year-round through 2030, with approximately 20 to 30 days of drilling per well.

Post-drilling phase and WCF startup, standard production and operation activities would take place. ConocoPhillips estimates that production would begin in the fourth quarter of 2025 with well maintenance operations occurring intermittently throughout the oilfield's lifespan.

ConocoPhillips plans to develop several bridges, installed via in-water pile-driving at Judy Creek, Fish Creek, Judy Creek Kayyaaq, Willow Creek 2, and Willow Creek 4. Pilings would be located above the ordinary high-water level and consist of sheet pile abutments done in sets of four, positioned approximately 12.2 to 21.3 m (40 to 70 ft) apart. Crossings over Willow Creek 4a and Willow Creek 8 would be constructed as single-span bridges, approximately 15.2 to 18.3 m (50 to 60 ft) apart using sheet pile abutments. Additionally, bridges would be constructed during the winter season from ice roads and pads. Screeding activities and marine traffic for the Willow project may also take place at the Oliktok Dock in the KRU.

Liberty Drilling and Production Island

The Liberty reservoir is located in Federal waters in Foggy Island Bay about 13 km (8 mi) east of the Endicott Satellite Drilling Island (SDI). Hilcorp plans to build a gravel island situated over the reservoir with a full on-island processing facility (similar to Northstar). The Liberty pipeline includes an offshore segment that would be buried in the seafloor for approximately 9.7 km (6 mi), and an onshore, VSM-mounted segment extending from the shoreline approximately 3.2 km (2 mi) to the Badami tie-in. Onshore infrastructure would include a gravel mine site, a 0.29-ha (0.71-ac) gravel pad at the Badami pipeline tie-in and a 6.1-ha (0.15-ac) gravel pad to allow for winter season ice road crossing. Environmental, archeological, and geotechnical work activities would take place to support the development and help inform decisionmaking. Development of the Liberty Island would include impact driving for conductor pipes/foundation pipes, vibratory drilling for conductor pipes, and vibratory and impact driving for sheet pile.

Road vehicles would use the Alaska Highway System to transport material and equipment from supply points in Fairbanks, Anchorage, or outside of Alaska to the supply hub of Deadhorse. Additionally, North Slope gravel roads would be used for transport from Deadhorse to the Endicott SDI. Existing gravel roads within the Endicott field between the MPI and the SDI would also be used to support the project.

During the winter seasons, workers would access the Liberty Island area from existing facilities via gravel roads and the ice road system. Construction vehicles would be staged at the construction sites, including the gravel mine. Access to the Liberty Drilling and Production Island (LDPI) by surface transportation is limited by periods when ice roads can be constructed and used. Additionally, surface transportation to the onshore pipeline can take place in winter on ice roads and can also occur in summer by approved tundra travel vehicles (

e.g.,

Rolligons). The highest volume of traffic would occur during gravel hauls to create the LDPI. Gravel hauling to the island would require approximately 14 trucks working for 76 days (BOEM 2018). An estimated 21,400 surface vehicle trips would occur per season during island construction.

In general, ice roads would be used in the winter seasons, marine vessels would be used in the summer seasons, helicopters would be used across both seasons, and hovercraft (if necessary) would be used during the shoulder season when ice roads and open water are not available. By spring breakup, all materials needed to support the ongoing construction would have been transported over the ice road system.

Additionally, personnel would access the island by helicopter (likely a Bell 212) or if necessary, via hovercraft. During the open-water season, continued use of helicopter and hovercraft would be utilized to transport personnel—however, crew boats may also be used.

Construction materials and supplies would be mobilized to the site by barge from West Dock or Endicott. Larger barges and tugs can over-winter in the Prudhoe Bay area and travel to the LDPI in the open-water season, generally being chartered on a seasonal basis or long-term contract. Vessels would include coastal and ocean-going barges and tugs to move large modules and equipment and smaller vessels to move personnel, supplies, tools, and smaller equipment. Barge traffic consisting of large ocean-going barges originating from Dutch Harbor is likely to consist of one-to-two vessels, approximately two-to-five times per year during construction, and only one trip every 5 years during operations. During the first 2 years following LDPI construction, hovercraft may make up to three trips per day from Endicott SDI to LDPI. After those 2 years, hovercraft may make up to two trips per day from Endicott SDI to LDPI (approximately 11.3 km [7 mi]).

Air operations are often limited by weather conditions and visibility. In general, air access would be used for movement of personnel and foodstuffs and for movement of supplies or equipment when necessary. Fixed-wing aircraft may be used on an as-needed basis for purposes of spill response (spill delineation) and aerial reconnaissance of anomalous conditions or unless otherwise required by regulatory authority. Helicopter use is planned for re-supply during the broken-ice seasons and access for maintenance and inspection of the onshore pipeline system. In the period between completion of hydro-testing and facilities startup, an estimated one-to-two helicopter flights per week are also expected for several weeks for personnel access and to transport equipment to the tie-in area. Typically, air traffic routing is as direct as possible from departure locations such as the SDI, West Dock, or Deadhorse to the LDPI, with routes and altitude adjusted to accommodate weather, other air traffic, and subsistence activities. Hilcorp would minimize potential disturbance to mammals from helicopter flights to support LDPI construction by limiting the flights to an established corridor from the LPDI to the mainland and except during landing and takeoff, and these flights would maintain a minimum altitude of 457 m (1,500 ft) above ground level (AGL) unless inclement weather requires deviation. Equipment located at the pipeline tie-in location and the pipeline shore landing would be accessed by helicopter or approved tundra travel vehicles to minimize impacts to the tundra.

Additionally, Hilcorp may use unmanned aerial surveys (UASs) during pile driving, pipe driving, and slope shaping and armament activities during the open-water season in Year 2 of construction and subsequently during decommissioning to monitor for whales or seals that may occur in incidental Level B harassment zones as described in the 2019 LOA issued by the National Marine Fisheries Service (NMFS 2020). Recent developments in the technical capacity and civilian use of UASs (defined as vehicles flying without a human pilot on board) have led to some investigations into potential use of these systems for monitoring and conducting aerial surveys of marine mammals (Koski et al. 2009; Hodgson et al. 2013). UASs, operating under autopilot and mounted with Global Positioning System (GPS) and imaging systems, have been used and evaluated in the Arctic (Koski et al. 2009) and have potential to replace traditional manned aerial surveys and provide an improved method for monitoring marine mammal populations. Hilcorp plans to seek a waiver, if necessary, from the Federal Aviation Administration (FAA) to operate the UAS above 122 m (400 ft) and beyond the line of sight of the pilot. Ground control for the UAS would be located at Liberty Island, Endicott, or another shore-based facility close to Liberty (NMFS 2020).

After construction, aircraft, land vehicle, and marine traffic may be at similar levels as those described for Northstar Island, although specific details beyond those presented here are not presently known.

Ice roads would be used for onshore and offshore access, installing the pipeline, hauling gravel used to construct the island, moving equipment on/off the island, and personnel and supply transit. Ice road construction can typically be initiated in mid- to late-December and can be maintained until mid-May, weather depending. Ice road #1 would 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 would be approximately 37 m wide (120 ft) with a driving lane of approximately 12 m (40 ft) and cover approximately 64.8 ha (160 ac) of sea ice. Ice road #2 (approximately 11.3 km [7 mi]) would connect the LDPI to the proposed Kadleroshilik River gravel mine site and then would continue to the juncture with the Badami ice road (which is ice road #4). It would be approximately 15 m (50 ft) wide. Ice road #3 (approximately 9.6 km [6 mi], termed the “Midpoint Access Road”) would intersect the SDI to LDPI ice road and the ice road between the LDPI and the mine site. It would be approximately 12 m (40 ft) wide. Ice road #4 (approximately 19.3 km [12 mi]), located completely onshore, would parallel the Badami pipeline and connect the mine site with the Endicott road.

All four ice roads would be constructed for the first 3 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. In addition to the ice roads, three ice pads are proposed to support construction activities (Year 2 and Year 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 107 by 213 m (350 by 700 ft) 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 may include spill training exercises, pipeline surveys, snow clearing, and work conducted by other snow vehicles such as a Pisten Bully, snow machine, or Rolligon. Prior to March 1, these activities would occur outside of the delineated ice road/trail and shoulder areas.

The LDPI would include a self-contained offshore drilling and production facility located on an artificial gravel island with a subsea pipeline to shore. The LDPI would be located approximately 8 km (5 mi) offshore in Foggy Island Bay and 11.7 km (7.3 mi) southeast of the existing SDI on the Endicott causeway. The LDPI would be constructed of reinforced gravel in 5.8 m (19 ft) of water and have a working surface of approximately 3.8 ha (9.3 ac). A steel sheet pile wall would surround the island to stabilize the placed gravel, and the island would include a slope protection bench, dock and ice road access, and a seawater intake area.

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 would 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) would 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 an 18.3-m (60-ft)-wide bench covered with a linked concrete mat that extends from a sheet pile wall surrounding the island to slightly above medium lower low water. 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 would 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 would 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 26.4 m (86.5 ft) into the water, terminating at a depth of 5.8 m (19 ft). In total, from the sheet pile wall, the bench and concrete mat would extend 44.7 m (146.5 ft). Island slope protection is required to ensure 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 would 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 would consist of a visual inspection of the dock and sheet pile enclosure that would document the condition of the island bench and ramps. The below-water slopes would be inspected by divers or, if water clarity allows, remotely by underwater cameras contracted separately by Hilcorp. The results of the below-water inspection would be recorded for repair if needed. No vessels would be required. Multi-beam bathymetry and side-scan sonar imagery of the below-water slopes and adjacent sea bottom would be acquired using a bathymetry vessel. The sidescan sonar would operate at a frequency between 200 and 400 kHz. The single-beam echosounder would operate at a frequency of about 210 kHz.

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. Sheet pile driving is anticipated to be conducted between March and August, during approximately 4 months of the ice-covered season and, if necessary, approximately 15 days during the open-water season. Sheet pile driving methods and techniques are expected to be similar to the installation of sheet piles at Northstar during which all pile driving was completed during the ice-covered season. Therefore, Hilcorp anticipates most or all sheet pile would be installed during ice-covered conditions. Hilcorp anticipates driving up to 20 piles per day to a depth of 7.62 m (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 (100 strikes) of impact driving to obtain the final desired depth for each sheet pile. To finish installing up to 20 piles per day, the impact hammer would be used a maximum of 40 minutes per day with an anticipated duration of 20 minutes per day.

For vibratory driving, pile penetration speed can vary depending on ground conditions, but a minimum sheet pile penetration speed is 0.5 m (20 in) 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 1 m (40 in) 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 would be higher on the west side than on the east side. At the top of the sheet-pile wall, overhanging steel “parapet” would 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 49 m (160 ft) 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, based on the 20 percent impact hammer usage factor (USDOT 2006.), it is expected that two cumulative hours of impact pipe driving (4,400 to 3,600 strikes) would occur over a 10.5 non-consecutive hour day. Conductor pipe driving is anticipated to be conducted between March and August and take 16 days total, installing one pipe per day. 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.

The LDPI layout includes areas for staging, drilling, production, utilities, a camp, a relief well, a helicopter landing pad, and two docks to accommodate barges, a hovercraft, and small crew boats. It would also have ramps for ice road and amphibious vehicle access. An STP would also be located at the facility to treat seawater and then commingle it with produced water to be injected into the Liberty Reservoir to maintain reservoir pressure. Treated seawater would be used to create potable water and utility water for the facility. A membrane bioreactor would treat sanitary wastewater, and remaining sewage solids would be incinerated on the island or stored in enclosed tanks prior to shipment to Deadhorse for treatment.

All modules, buildings, and material for onsite construction would be trucked to the North Slope via the Dalton Highway and staged at West Dock, Endicott SDI, or in Deadhorse. Another option is to use ocean-going barges from Dutch Harbor to transport materials or modules to the island during the open-water season.

Depending on the season, equipment and material would be transported via coastal barges in open water, or ice roads from SDI in the winter. The first modules would be delivered in the third quarter of Year 2 to support the installation of living, drilling, and production facilities. Remaining process modules would be delivered to

correspond with first oil and the ramp-up in drilling capacity.

Onsite facility installation would commence in August of Year 2 and be completed by the end of Year 4 (May) to accommodate the overall construction and production ramp-up schedule. Some facilities that are required early would be barged in the third quarter of Year 2 and would be installed and operational by the end of the fourth quarter of Year 2. Other modules would be delivered as soon as the ice road from SDI is in place. The drilling unit and associated equipment would be transferred by barge through Dutch Harbor or from West Dock to the LDPI during the open-water season in Year 2 using a seagoing barge and ocean class tug. The seagoing barge is ~30.5 m (100 ft) wide and ~122 m (400 ft) long, and the tug is ~30.5 m (100 ft) long. Although the exact vessels to be used are unknown, Crowley lists Ocean class tugs at <1,600 gross registered tonnage. The weight of the seagoing barge is not known at this time.

Hilcorp would install a pipe-in-pipe subsea pipeline consisting of a 30.5-cm (12-in)-diameter inner pipe and a 40.6-cm (16-in)-diameter outer pipe to transport oil from the LDPI to the existing Badami 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 EIS available at

https://www.boem.gov/Hilcorp-Liberty/.

The pipeline would extend from the LDPI, across Foggy Island Bay, and terminate onshore at the existing Badami Pipeline tie-in location. For the marine segment, construction would progress from shallower water to deeper water with multiple construction spreads.

To install the pipeline, a trench would be excavated using ice-road-based long-reach excavators with pontoon tracks. The pipeline bundle would be lowered into the trench using side booms to control its vertical and horizontal position, and the trench would be backfilled by excavators using excavated trench spoils and select backfill. Hilcorp intends to place all material back in the trench slot. All work would be done from ice roads using conventional excavation and dirt-moving construction equipment. The target trench depth is 2.7 to 3.4 m (9 to 11 ft) with a proposed maximum depth of cover of approximately 2.1 m (7 ft). The pipeline would be approximately 9 km (5.6 mi) long.

At the pipeline landfall (where the pipeline transitions from onshore to offshore), Hilcorp would construct an approximately 0.6-ha (1.4-ac) trench to protect against coastal erosion and ice ride-up associated with onshore sea ice movement and to accommodate the installation of thermosiphons (heat pipes that circulate fluid based on natural convection to maintain or cool ambient ground temperature) along the pipeline. The onshore pipeline would cross the tundra for almost 2.4 km (1.5 mi) until it intersects the existing Badami pipeline system. The single wall 30.5-cm (12-in) pipeline would rest on 150 to 170 VSMs, spaced approximately 15 m (50 ft) apart to provide the pipeline a minimum 2.1-m (7-ft) clearance above the tundra. Hydro-testing (pressure testing using sea water) of the entire pipeline would be required to complete pipeline commissioning.

The final drill rig has yet to be chosen but has been narrowed to 2 options and would 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 not only to 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. While Hilcorp is proposing a 16-well design, only 10 wells would be drilled. The six additional well slots would be available as backups or for potential in-fill drilling if needed during the project life.

Drilling would be done using a conventional rotary drilling rig, initially powered by diesel, and eventually converted to fuel gas produced from the third well. Gas from the third well would also replace diesel fuel for the grind-and-inject facility and production facilities. A location on the LDPI is designated for drilling a relief well, if needed.

Process facilities on the island would separate crude oil from produced water and gas. Gas and water would be injected into the reservoir to provide pressure support and increase recovery from the field. A single-phase subsea pipe-in-pipe pipeline would transport sales-quality crude from the LDPI to shore, where an aboveground pipeline would transport crude to the existing Badami pipeline. From there, crude would be transported to the Endicott Sales Oil Pipeline, which ties into Pump Station 1 of the TAPS for eventual delivery to a refinery.

North Slope Gas Development

The AOGA Request discusses two projects currently submitted for approval and permitting that would transport natural gas from the North Slope via pipeline. Only a small fraction of this project would fall within the 40-km (25-mi) inland jurisdiction area of this ITR. The two projects are the Alaska Liquified Natural Gas Project (Alaska LNG) and the Alaska Stand Alone Pipeline (ASAP). Both of these projects are discussed below and their effects analyzed in this ITR, but only one project could be constructed during the 2021-2026 period.

Alaska Liquefied Natural Gas Project (Alaska LNG)

The Alaska LNG project has been proposed by the Alaska Gasline Development Corporation (AGDC) to serve as a single integrated project with several facilities designed to liquefy natural gas. The fields of interest are the Point Thomson Unit (PTU) and PBU production fields. The Alaska LNG project would consist of a Gas Treatment Plant (GTP); a Point Thomson Transmission Line (PTTL) to connect the GTP to the PTU gas production facility; a Prudhoe Bay Transmission Line (PBTL) to connect the GTP to the PBU gas production facility; a liquefaction facility in southcentral Alaska; and a 1,297-km (807-mi)-long, 107-cm (42-in)-diameter pipeline (called the Mainline) that would connect the GTP to the liquefaction facility. Only the GTP, PTTL, PBTL, a portion of the Mainline, and related ancillary facilities would be located within the geographic scope of AOGA's Request. Related components would require the construction of ice roads, ice pads, gravel roads, gravel pads, camps, laydown areas, and infrastructure to support barge and module offloading.

Barges would be used to transport GTP modules at West Dock at Prudhoe Bay several times annually, with GTP modules being offloaded and transported by land to the proposed GTP facility in the PBU. However, deliveries would require deep draft tug and barges to a newly constructed berthing site at the northeast end of West Dock. Additionally, some barges would continue to deliver small modules and supplies to Point Thomson. Related activities include screeding, shallow draft tug use, sea ice cutting, gravel placement, sea ice road and sea ice pad development, vibratory and impact pile driving, and the use of an offshore barge staging area.

A temporary bridge (developed from ballasted barges) would be developed to assist in module transportation. Barges would be ballasted when the area is ice-free and then removed and overwintered at West Dock before the sea freezes over. A staging area would then be used to prepare modules for transportation, maintenance, and gravel road development. Installation of ramps and fortification would utilize vibratory and impact pile driving. Seabed preparations and level surface preparations (

i.e.,

ice cutting, ice road development, gravel placement, screeding) would take place as needed. Breasting/mooring dolphins would be installed at the breach point via pile driving to anchor and stabilize the ballasted barges.

A gravel pad would be developed to assist construction of the GTP, adjacent camps, and other relevant facilities where work crews utilize heavy equipment and machinery to assemble, install, and connect the GTP modules. To assist, gravel mining would use digging and blasting, and gravel would be placed to create pads and develop or improve ice and gravel roads.

Several types of development and construction would be required at different stages of the project. The construction of the Mainline would require the use of ice pads, ice roads, gravel roads, chain trenchers, crane booms, backhoes, and other heavy equipment. The installation of the PTTL and PBTL would require ice roads, ice pads, gravel roads, crane booms, mobile drills or augers, lifts, and other heavy equipment. After installation, crews would work on land and streambank restoration, revegetation, hydrostatic testing, pipeline security, and monitoring efforts. The development of the ancillary facility would require the construction of ice roads, ice pads, as well as minimal transportation and gravel placement.

Alaska Stand Alone Pipeline (ASAP)

The ASAP is the alternative project option that AGDC could utilize, allowing North Slope natural gas to be supplied to Alaskan communities. ASAP would require several components, including a Gas Conditioning Facility (GCF) at Prudhoe Bay; a 1,180-km (733-mi)-long, 0.9-m (36-in)-diameter pipeline that would connect the GCF to a tie-in found in southcentral Alaska (called the Mainline); and a 48-km (30-m), 0.3-m (12-in)-diameter lateral pipeline connecting the Mainline pipeline to Fairbanks (referred to as the Fairbanks Lateral). Similar to the Alaska LNG pipeline, only parts of this project would fall within the geographic scope of this ITR. These relevant project components are the GCF, a portion of the ASAP Mainline, and related ancillary facilities. Construction would include the installation of supporting facilities and infrastructure, ice road and pad development, gravel road and pad development, camp establishment, laydown area establishment, and additional infrastructure to support barge and module offloading.

Barges would be used to transport the GCF modules to West Dock in Prudhoe Bay and would be offloaded and transported by ground to the proposed facility site within the PBU. Module and supply deliveries would utilize deep draft tugs and barges to access an existing berthing location on the northeast side of West Dock called DH3. Maintenance on DH3 would be required to accommodate the delivery of larger loads and would consist of infrastructure reinforcement and elevation increases on one of the berths. In the winter, a navigational channel and turn basin would be dredged to a depth of 2.7 m (9 ft). Dredged material would be disposed of on ground-fast ice found in 0.6-1.2 m (2-4 ft) deep water in Prudhoe Bay. An offshore staging area would be developed approximately 4.8-8 km (3-5 mi) from West Dock to allow deep draft tugs and barges to stage before further transportation to DH3 and subsequent offload by shallow draft tugs. Other activities include seabed screeding, gravel placement, development of a sea ice road and pads, and pile driving (vibratory and impact) to install infrastructure at West Dock.

A temporary bridge (composed of ballasted barges and associated infrastructure) paralleling an existing weight-limited bridge would be developed to assist in transporting large modules off West Dock. Barges would be ballasted when the area is ice-free and then removed and overwintered at West Dock before the sea freezes over. A staging area would be used to prepare modules for transportation, maintenance, and gravel road development. The bridge construction would require ramp installation, fortification through impact, and vibratory pile driving. Support activities (development of ice roads and pads, gravel roads and pads, ice cutting, seabed screeding) would also take place. Breasting/mooring dolphins would be installed at the breach point via pile driving to anchor and stabilize the ballasted barges.

A gravel facility pad would be formed to assist in the construction of the GCF. Access roads would then be developed to allow crews and heavy equipment to install and connect various GCF modules. Gravel would be obtained through digging, blasting, transportation, gravel pad placement, and improvements to other ice and gravel roads.

The construction of the Mainline pipeline would require the construction of ice pads, ice roads, and gravel roads along with the use of chain trenchers, crane booms, backhoes, and other heavy equipment. Block valves would be installed above ground along the length of the Mainline. After installation, crews would work on land and streambank restoration, revegetation, hydrostatic testing, pipeline security, and monitoring efforts.

Pikka Unit

The Pikka Development (formally known as the Nanshuk Project) is located approximately 83.7 km (52 mi) west of Deadhorse and 11.3 km (7 mi) northeast of Nuiqsut. Oil Search Alaska operates leases held jointly between the State of Alaska and ASRC located southeast of the East Channel of the Colville River. Pikka is located further southwest from the existing Oooguruk Development Project, west of the existing KRU, and east of Alpine and Alpine's Satellite Development Projects. Most of the infrastructure is located over 8 km (5 mi) from the coast within the Pikka Unit; however, Oil Search Alaska expects some smaller projects and activities to occur outside the unit to the south, east, and at Oliktok Point.

The Pikka Project would include a total of 3 drill-sites for approximately 150 (production, injectors, underground injection) wells, as well as the Nanshuk Processing Facility (NPF), the Nanushuk Operations Pad, a tie-in pad (TIP), various camps, warehouses, facilities on pads, infield pipelines, pipelines for import and export activities, various roads (ice, infield, access), a boat ramp, and a portable water system. Additionally, there are plans to expand the Oliktok Dock and to install an STP adjacent to the already existing infrastructure. A make-up water pipeline would also be installed from the STP to the TIP. Oil Search Alaska also plans to perform minor upgrades and maintenance, as necessary, to the existing road systems to facilitate transportation of sealift modules from Oliktok Point to the Pikka Unit.

Oil Search Alaska plans to develop a pad to station the NPF and all relevant equipment and operations (

i.e.,

phase separation, heating and cooling, pumping, gas treatment and compression for gas injections, water treatment for injection). All oil procured, processed, and designated for

sale would travel from the NPF to the TIP near Kuparuk's CPF 2 via the Pikka Project pipeline that would tie in to the Kuparuk Sales Pipeline and would then be transported to TAPS. Construction of the pad would allow for additional space that could be repurposed for drilling or for operational use during the development of the Pikka Project. This pad would contain other facilities required for project operation and development, including: Metering and pigging facilities; power generation facilities; a truck fill station; construction material staging areas; equipment staging areas; a tank farm (contains diesel, refined fuel, crude oil, injection water, production chemicals, glycol, and methanol storage tanks); and a central control room. All major components required for the development of the NPF would be constructed off-site and brought in via truck or barge during the summer season. Barges would deliver and offload necessary modules at Oliktok Dock, which would travel to the NPF site during summer months. Seabed screeding would occur at Oliktok Point to maintain water depth for necessary barges.

Pikka would use gravel roads to the Unit, which would allow year-round access from the Dalton Highway. All gravel needed for project activities (approximately 112 ha [276 ac]) would be sourced from several existing gravel mine sites. A majority of gravel acquisition and laying would occur during the winter season and then be compacted in the summer. All equipment and supplies necessary would be brought in on existing roads from Anchorage or Fairbanks to Deadhorse. Supplies and equipment would then be forwarded to the Pikka Unit; no aerial transportation for supplies is expected. Regular traffic is expected once construction of the roads is completed; Oil Search Alaska expects arterial routes between the processing facilities and camps to experience the heaviest use of traffic. Drill-site access roads are expected to experience the least amount of traffic; however, drill-site traffic is expected to increase temporarily during periods of active drilling, maintenance, or other relevant aspects of the project. Standard vehicles would include light passenger trucks, heavy tractor-trailer trucks, heavy equipment, and oil rigs.

Several types of aircraft operations are expected at the Pikka Unit throughout the 2021-2026 period. Personnel would be transported to Pikka via commercial flights from Deadhorse Airport and by ground-based vehicle transport. Currently, there is no plan to develop an airstrip at Pikka. Personnel flights are expected to be infrequent to and from the Pikka Unit; however, Oil Search Alaska expects that some transport directly to the Unit may be required. Several environmental studies performed via aircraft are expected during the ITR period. Some of these include AIR surveys, cultural resources, stick-picking, and hydrology studies. AIR surveys in support of the Pikka Unit would occur annually to locate polar bear dens.

Summer travel would utilize vehicles such as Rolligons and Tuckers to assess pipelines not found adjacent to the gravel roads. During 24-hour sunlight periods, these vehicles would operate across all hours. Stick-picking and thermistor retrieval would also occur in the summer. In the winter, ice roads would be constructed across the Unit. These ice roads would be developed to haul gravel from existing mine sites to haul gravel for road and pad construction. Ice roads would also be constructed to support the installation of VSM and pipelines. Off-road winter vehicles would be used when the tundra is frozen and covered with snow to provide maintenance and access for inspection. Temporary ice roads and ice pads would be built to allow for the movement and staging of heavy equipment, maintenance, and construction. Oil Search Alaska would perform regular winter travel to support operations across the Pikka Unit.

Oil Search Alaska plans to install a bridge over the Kachemach River (more than 8 km [5 mi] from the coast) and install the STP at Oliktok Point. Both projects would require in-water pile driving, which is expected to take place during the winter seasons. In-water pile driving (in the winter), placement of gravel fill (open-water period), and installation of the STP barge outfall structure (open-water period) would take place at Oliktok Point. Dredging and screeding activities would prepare the site for STP and module delivery via barge. Annual maintenance screeding and dredging (expected twice during the Request period) may be needed to maintain the site. Dredging spoils would be transported away, and all work would occur during the open-water season between May and October. Screeding activities are expected to take place annually over the course of a 2-week period, depending on stability and safety needs.

Gas Hydrate Exploration and Research

The U.S. Geological Survey (USGS) estimates that the North Slope contains over 54 trillion cubic feet of recoverable gas assets (Collette

et al.

2019). Over the last 5 years, Industry has demonstrated a growing interest in the potential to explore and extract these reserves. Federal funds from the Department of Energy have been provided in the past to support programs on domestic gas hydrate exploration, research, and development. Furthermore, the State of Alaska provides support for gas hydrate research and development through the development of the Eileen hydrate trend deferred area near Milne Point, with specific leases being offered for gas hydrate research and exploration.

As of 2021, a few gas hydrate exploration and test wells have been drilled within the Beaufort Sea region. Due to the support the gas hydrate industry has received, AOGA expects continued interest to grow over the years. As such, AOGA expects that a relatively low but increasing amount of gas hydrate exploration and research is expected throughout the 2021-2026 period.

Environmental Studies

Per AOGA's Request, Industry would continue to engage in various environmental studies throughout the life of the ITR. Such activities include: Geological and geotechnical surveys (

i.e.,

seismic surveys); surveys on geomorphology (soils, ice content, permafrost), archeology and cultural resources; vegetation mapping; analysis of fish, avian, and mammal species and their habitats; acoustic monitoring; hydrology studies; and various other freshwater, marine, and terrestrial studies of the coastal and offshore regions within the Arctic. These studies typically include various stakeholders, including consultants and consulting companies; other industries; government; academia (university-level); nonprofits and nongovernmental organizations; and local community parties. However, AOGA's 2021-2026 ITR Request seeks coverage only for environmental studies directly related to Industry activities (

e.g.,

monitoring studies in response to regulatory requirements). No third-party studies will be covered except by those mentioned in this ITR and the AOGA Request.

During the 2021-2026 lifespan of the ITR, Industry would continue studies that are conducted for general monitoring purposes for regulatory and/or permit requirements and for expected or planned exploration and development activities within the Beaufort Sea region. Environmental studies are anticipated to occur during the summer season as to avoid overlap with any denning polar bears. Activities

may utilize vessels, fixed-wing aircrafts, or helicopters to access research sites.

Mitigation Measures

AOGA has included in their Request a number of measures to mitigate the effects of the proposed activities on Pacific walruses and polar bears. Many of these measures have been historically used by oil and gas entities throughout the North Slope of Alaska and have been developed as a part of past coordination with the Service. Measures include: Development and adherence to polar bear and Pacific walrus interaction plans; design of facilities to reduce the possibility of polar bears reaching attractants; avoidance of operating equipment near potential den locations; flying aircraft at a minimum altitude and distance from polar bears and hauled out Pacific walruses; employing trained protected species observers; and reporting all polar bear or Pacific walrus encounters to the Service. Additional descriptions of these measures can be found in the AOGA Request for an ITR at:

www.regulations.gov

in Docket No. FWS-R7-ES-2021-0037.

Maternal Polar Bear Den Survey Flights

Per AOGA's Request, Industry will also conduct aerial infrared (AIR) surveys to locate maternal polar bear dens in order to mitigate potential impacts to mothers and cubs during the lifetime of this ITR. AIR surveys are used to detect body heat emitted by polar bears, which, in turn, is used to determine potential denning polar bears. AIR surveys are performed in winter months (December or January) before winter activities commence. AIR imagery is analyzed in real-time during the flight and then reviewed post-flight with the Service to identify any suspected maternal den locations, ensure appropriate coverage, and check the quality of the images and recordings. Some sites may need to be resurveyed if a suspected hotspot (heat signature detectable in a snowdrift) is observed. These followup surveys of hotspots are conducted in varying weather conditions or using an electro-optical camera during daylight hours. On-the-ground reconnaissance or the use of scent-training dogs may also be used to recheck the suspected den.

Surveys utilize AIR cameras on fixed-wing aircrafts with flights typically flown between 245-457 meters (800-1,500 feet) above ground level at a speed of <185 km/h (<115 mph). Surveys typically occur twice a day (weather permitting) during periods of darkness (civil twilight) across the North Slope for less than 4.5 hours per survey. Surveys are highly dependent on the weather as it can affect the image quality of the AIR video and the safety of the participants. These surveys do not follow a typical transect configuration; instead they are concentrated on areas that would be suitable for polar bear denning activity such as drainages, banks, bluffs, or other areas of topographic relief around sites where Industry has winter activities, tundra travel, or ice road construction planned or anticipated. As part of AOGA's Request and as described in the mitigation measures included in this ITR, all denning habitat within 1 mile of the ice-season industrial footprint will be surveyed twice each year. In years where seismic surveys are proposed, all denning habitat within the boundaries of the seismic surveys will be surveyed three times, and a third survey will be conducted on denning habitat along the pipeline between Badami and the road to Endicott Island. Greater detail on the timing of these surveys can be found in

Methods for Modeling the Effects of Den Disturbance.

A suspected heat signature observed in a potential den found via AIR is classified into three categories: A hotspot, a revisit, or a putative den. The following designations are discussed below.

A “hotspot” is a warm spot found on the AIR camera indicative of a polar bear den through the examination of the size and shape near the middle of the snow drift. Signs of wildlife presence (

e.g.,

digging, tracks) may be present and visible. Suspected dens that are open (

i.e.,

not drifted closed by the snow) are considered hotspots because polar bears may dig multiple test evacuation sites when searching for an appropriate place to den and unused dens will cool down and be excluded from consideration. Hotspots are reexamined and either eliminated or upgraded to a “putative den” designation. Industry representatives, in coordination and compliance with the Service, may utilize other methods outside of AIR to gather additional information on a suspected hotspot.

A “revisit” is a designation for a warm spot in a snowdrift but lacking signs of a polar bear den (

e.g.,

tailings pile, signs of animal activity, appropriate shape or size). These categorizations are often revisited during a subsequent survey, upgraded to a “hotspot” designation, or eliminated from further consideration pending the evidence presented.

A “putative den” is a hotspot that has maintained a distinct heat signature longer than a day and is found within the appropriate habitat. The area may show evidence of an animal's presence that may not definitively be attributed to a non-polar bear species or cause (

e.g.,

a fox or other animal digging). The final determination is often unknown as these sites are not investigated further, monitored, or revisited in the spring.

When and if a putative den is found near planned or existing infrastructure or activities, the Industry representatives will immediately cease operations within 1 mile of the location and coordinate with the Service to mitigate any potential disturbances while further information is obtained.

Evaluation of the Nature and Level of Activities

The annual level of activity at existing production facilities in the Request will be similar to that which occurred under the previous regulations. The increase in the area of the industrial footprint with the addition of new facilities, such as drill pads, pipelines, and support facilities, is at a rate consistent with prior 5-year regulatory periods. Additional onshore and offshore facilities are projected within the timeframe of these regulations and will add to the total permanent activities in the area. This rate of expansion is similar to prior production schedules.

Description of Marine Mammals in the Specified Geographic Region

Polar Bear

Polar bears are distributed throughout the ice-covered seas and adjacent coasts of the Arctic region. The current total polar bear population is estimated at approximately 26,000 individuals (95 percent Confidence Interval (CI) = 22,000-31,000, Wiig

et al.

2015; Regehr

et al.

2016) and comprises 19 stocks ranging across 5 countries and 4 ecoregions that reflect the polar bear dependency on sea-ice dynamics and seasonality (Amstrup et al. 2008). Two stocks occur in the United States (Alaska) with ranges that extend to adjacent countries: Canada (the Southern Beaufort Sea (SBS) stock) and the Russia Federation (the Chukchi/Bering Seas stock). The discussion below is focused on the Southern Beaufort Sea stock of polar bears, as the proposed activities in this ITR would overlap only their distribution.

Polar bears typically occur at low, uneven densities throughout their circumpolar range (DeMaster and Stirling 1981, Amstrup

et al.

2011, Hamilton and Derocher 2019) in areas where the sea is ice-covered for all or part of the year. They are typically most abundant on sea-ice, near polynyas (

i.e.,

areas of persistent open water) and

fractures in the ice, and over relatively shallow continental shelf waters with high marine productivity (Durner et al. 2004). This sea-ice habitat favors foraging for their primary prey, ringed seals

(Pusa hispida),

and other species such as bearded seals

(Erignathus barbatus)

(Thiemann

et al.

2008, Cherry

et al.

2011, Stirling and Derocher 2012). Although over most of their range polar bears prefer to remain on the sea-ice year-round, an increasing proportion of stocks are spending prolonged periods of time onshore (Rode et al. 2015, Atwood et al. 2016b). While time spent on land occurs primarily in late summer and autumn (Rode et al. 2015, Atwood et al. 2016b), they may be found throughout the year in the onshore and nearshore environments. Polar bear distribution in coastal habitats is often influenced by the movement of seasonal sea ice (Atwood et al. 2016b, Wilson et al. 2017) and its direct and indirect effects on foraging success and, in the case of pregnant females, also dependent on availability of suitable denning habitat (Durner et al. 2006, Rode et al. 2015, Atwood et al. 2016b).

In Alaska during the late summer/fall period (July through November), polar bears from the Southern Beaufort Sea stock often occur along the coast and barrier islands, which serve as travel corridors, resting areas, and to some degree, foraging areas. Based on Industry observations and coastal survey data acquired by the Service (Wilson

et al.

2017), encounter rates between humans and polar bears are higher during the fall (July to November) than in any other season, and an average of 140 polar bears may occur on shore during any week during the period July through November between Utqiagvik and the Alaska—Canada border (Wilson

et al.

2017). The length of time bears spend in these coastal habitats has been linked to sea ice dynamics (Rode

et al.

2015, Atwood et al. 2016b). The remains of subsistence-harvested bowhead whales at Cross and Barter islands provide a readily available food attractant in these areas (Schliebe

et al.

2006). However, the contribution of bowhead carcasses to the diet of SBS polar bears varies annually (

e.g.,

estimated as 11-26 percent and 0-14 percent in 2003 and 2004, respectively) and by sex, likely depending on carcass and seal availability as well as ice conditions (Bentzen et al. 2007).

Polar bears have no natural predators (though cannibalism is known to occur; Stirling et al. 1993, Amstrup et al. 2006b). However, their life-history (

e.g.,

late maturity, small litter size, prolonged breeding interval) is conducive to low intrinsic population growth (

i.e.,

growth in the absence of human-caused mortality), which was estimated at 6 percent to 7.5 percent for the SBS stock during 2004-2006 (Regehr et al. 2010; Hunter et al. 2010). The lifespan of wild polar bears is approximately 25 years (Rode et al. 2020). Females reach sexual maturity at 3-6 years old giving birth 1 year later (Ramsay and Stirling 1988). In the SBS region, females typically give birth at 5 years old (Lentfer & Hensel 1980). On average, females in the SBS produce litter sizes of 1.9 cubs (SD=0.5; Smith et al. 2007, 2010, 2013; Robinson 2014) at intervals that vary from 1 to 3 or more years depending on cub survival (Ramsay and Stirling 1988) and foraging conditions. For example, when foraging conditions are unfavorable, polar bears may delay reproduction in favor of survival (Derocher and Stirling 1992; Eberhardt 2002). The determining factor for growth of polar bear stocks is adult female survival (Eberhardt 1990). In general, rates above 90 percent are essential to sustain polar bear stocks (Amstrup and Durner 1995) given low cub litter survival, which was estimated at 50 percent (90 percent CI: 33-67 percent) for the SBS stock during 2001-2006 (Regehr et al. 2010). In the SBS, the probability that adult females will survive and produce cubs-of-the-year is negatively correlated with ice-free periods over the continental shelf (Regehr et al. 2007a). In general, survival of cubs-of-the-year is positively related to the weight of the mother and their own weight (Derocher and Stirling 1996; Stirling et al. 1999).

Females without dependent cubs typically breed in the spring (Amstrup 2003, Stirling et al. 2016). Pregnant females enter maternity dens between October and December (Durner et al. 2001; Amstrup 2003), and young are usually born between early December and early January (Van de Velde et al. 2003). Only pregnant females den for an extended period during the winter (Rode et al. 2018). Other polar bears may excavate temporary dens to escape harsh winter conditions; however, shelter denning is rare for Alaskan polar bear stocks (Olson et al. 2017).

Typically, SBS females denning on land emerge from the den with their cubs around mid-March (median emergence: March 11, Rode

et al.

2018, USGS 2018), and commonly begin weaning when cubs are approximately 2.3-2.5 years old (Ramsay and Stirling 1986, Arnould and Ramsay 1994, Amstrup 2003, Rode 2020). Cubs are born blind, with limited fat reserves, and are able to walk only after 60-70 days (Blix and Lentfer 1979; Kenny and Bickel 2005). If a female leaves a den during early denning, cub mortality is likely to occur due to a variety of factors including susceptibility to cold temperatures (Blix and Lentfer 1979, Hansson and Thomassen 1983, Van de Velde 2003), predation (Derocher and Wiig 1999, Amstrup

et al.

2006b), and mobility limitations (Lentfer 1975). Therefore, it is thought that successful denning, birthing, and rearing activities require a relatively undisturbed environment. A more detailed description of the potential consequences of disturbance to denning females can be found below in

Potential Effects of Oil and Gas Industry Activities on Pacific Walrus, Polar Bear, and Prey Species:

Polar Bear: Effects to Denning Bears.

Radio and satellite telemetry studies indicate that denning can occur in multiyear pack ice and on land (Durner et al. 2020). The proportion of dens on land has been increasing along the Alaska region (34.4 percent in 1985-1995 to 55.2 percent in 2007-2013; Olson et al. 2017) likely in response to reductions in stable old ice, which is defined as sea ice that has survived at least one summer's melt (Bowditch 2002), increases in unconsolidated ice, and lengthening of the melt season (Fischbach et al. 2007, Olson et al. 2017). If sea-ice extent in the Arctic continues to decrease and the amount of unstable ice increases, a greater proportion of polar bears may seek to den on land (Durner et al. 2006, Fischbach et al. 2007, Olson et al. 2017).

In Alaska, maternal polar bear dens occur on barrier islands (linear features of low-elevation land adjacent to the main coastline that are separated from the mainland by bodies of water), river bank drainages, and deltas (

e.g.,

those associated with the Colville and Canning Rivers), much of the North Slope coastal plain (in particular within the 1002 Area,

i.e.,

the land designated in section 1002 of the Alaska National Interest Lands Conservation Act—part of ANWR in northeastern Alaska; Amstrup 1993, Durner

et al.

2006), and coastal bluffs that occur at the interface of mainland and marine habitat (Durner et al. 2006, 2013, 2020; Blank 2013; Wilson and Durner 2020). These types of terrestrial habitat are also designated as critical habitat for the polar bear under the Endangered Species Act (75 FR 76086, December 7, 2010). Management and conservation concerns for the SBS and Chukchi/Bering Seas (CS) polar bear stocks include sea-ice loss due to climate change, human-bear conflict, oil and gas industry activity, oil spills and contaminants, marine shipping, disease, and the potential for

overharvest (Regehr et al. 2017; U.S. Fish and Wildlife Service 2016). Notably, reductions in physical condition, growth, and survival of polar bears have been associated with declines in sea-ice (Rode et al. 2014, Bromaghin et al. 2015, Regehr et al. 2007, Lunn et al. 2016). The attrition of summer Arctic sea-ice is expected to remain a primary threat to polar bear populations (Amstrup et al. 2008, Stirling and Derocher 2012), since projections indicate continued climate warming at least through the end of this century (Atwood et al. 2016a, IPCC 2014) (see section on Climate Change for further details).

In 2008, the Service listed polar bears as threatened under the Endangered Species Act of 1973, as amended (16 U.S.C. 1531

et seq.;

ESA) due to the loss of sea-ice habitat caused by climate change (73 FR 28212, May 15, 2008). The Service later published a final rule under section 4(d) of the ESA for the polar bear, which was vacated and then reinstated when procedural requirements were satisfied (78 FR 11766, February 20, 2013). This section 4(d) rule provides for measures that are necessary and advisable for the conservation of polar bears. Specifically, the 4(d) rule: (a) Adopts the conservation regulatory requirements of the MMPA and the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) for the polar bear as the appropriate regulatory provisions, in most instances; (b) provides that incidental, nonlethal take of polar bears resulting from activities outside the bear's current range is not prohibited under the ESA; (c) clarifies that the 4(d) rule does not alter the section 7 consultation requirements of the ESA; and (d) applies the standard ESA protections for threatened species when an activity is not covered by an MMPA or CITES authorization or exemption.

The Service designated critical habitat for polar bear populations in the United States effective January 6, 2011 (75 FR 76086, December 7, 2010). The designation of critical habitat identifies geographic areas that contain features that are essential for the conservation of a threatened or endangered species and that may require special management or protection. Under section 7 of the ESA, if there is a Federal action, the Service will analyze the potential impacts of the action upon polar bears and any designated critical habitat. Polar bear critical habitat units include barrier island habitat, sea-ice habitat (both described in geographic terms), and terrestrial denning habitat (a functional determination). Barrier island habitat includes coastal barrier islands and spits along Alaska's coast; it is used for denning, refuge from human disturbance, access to maternal dens and feeding habitat, and travel along the coast. Sea-ice habitat is located over the continental shelf and includes water 300 m (~984 ft) or less in depth. Terrestrial denning habitat includes lands within 32 km (~20 mi) of the northern coast of Alaska between the Canadian border and the Kavik River and within 8 km (~5 mi) between the Kavik River and Utqiaġvik. The total area designated under the ESA as critical habitat covers approximately 484,734 km

2

(~187,157 mi

2

) and is entirely within the lands and waters of the United States. Polar bear critical habitat is described in detail in the final rule that designated polar bear critical habitat (75 FR 76086, December 7, 2010). A digital copy of the final critical habitat rule is available at:

http://www.fws.gov/r7/fisheries/mmm/polarbear/pdf/federal_register_notice.pdf.

Stock Size and Range

In Alaska, polar bears have historically been observed as far south in the Bering Sea as St. Matthew Island and the Pribilof Islands (Ray 1971). A detailed description of the SBS polar bear stock can be found in the Service's revised Polar Bear

(Ursus maritimus)

Stock Assessment Report (86 FR 33337, June 24, 2021). Digital copies of these Stock Assessment Report is are available at:

https://www.fws.gov/alaska/sites/default/files/2021-06/Southern%20Beaufort%20Sea%20SAR%20Final_May%2019rev.pdf.

and

https://www.fws.gov/alaska/sites/default/files/2021-06/Chukchi_Bering%20Sea%20SAR%20Final%20May%2019%20rev.pdf

.

Southern Beaufort Sea Stock

The SBS polar bear stock is shared between Canada and Alaska. Radio-telemetry data, combined with ear tag returns from harvested bears, suggest that the SBS stock occupies a region with a western boundary near Icy Cape, Alaska (Scharf

et al.

2019), and an eastern boundary near Tuktoyaktuk, Northwest Territories, Canada (Durner

et al.

2018).

The most recent population estimates for the Alaska SBS stock were produced by the U.S. Geological Survey (USGS) in 2020 (Atwood

et al.

2020) and are based on mark-recapture and collared bear data collected from the SBS stock from 2001 to 2016. The SBS stock declined from 2003 to 2006 (this was also reported by Bromaghin

et al.

2015) but stabilized from 2006 through 2015. The stock may have increased in size from 2009 to 2012; however, low survival in 2013 appears to have offset those gains. Atwood et al. (2020) provide estimates for the portion of the SBS stock only within the State of Alaska; however, their updated abundance estimate from 2015 is consistent with the estimate from Bromaghin et al. (2015) for 2010. Thus, the number of bears in the SBS stock is thought to have remained constant since the Bromaghin et al. (2015) estimate of 907 bears. This number is also supported by survival rate estimates provided by Atwood et al. (2020) that were relatively high in 2001-2003, decreased during 2004-2008, then improved in 2009, and remained high until 2015, except for much lower rates in 2012.

Pacific Walrus

Pacific walruses constitute a single panmictic population (Beatty et al. 2020) primarily inhabiting the shallow continental shelf waters of the Bering and Chukchi Seas where their distribution is largely influenced by the extent of the seasonal pack ice and prey densities (Lingqvist et al. 2009; Berta and Churchill 2012; USFWS 2017). From April to June, most of the population migrates from the Bering Sea through the Bering Strait and into the Chukchi Sea along lead systems that develop in the sea-ice and that are closely associated with the edge of the seasonal pack ice during the open-water season (Truhkin and Simokon 2018). By July, tens of thousands of animals can be found along the edge of the pack ice from Russian waters to areas west of Point Barrow, Alaska (Fay 1982; Gilbert et al. 1992; Belikov et al. 1996; USFWS 2017). The pack ice has historically advanced rapidly southward in late fall, and most walruses return to the Bering Sea by mid- to late-November. During the winter breeding season, walruses are found in three concentration areas in the Bering Sea where open leads, polynyas, or thin ice occur (Fay 1982; Fay et al. 1984, Garlich-Miller et al. 2011a; Duffy-Anderson et al. 2019). While the specific location of these groups varies annually and seasonally depending upon the extent of the sea-ice, generally one group occurs near the Gulf of Anadyr, another south of St. Lawrence Island, and a third in the southeastern Bering Sea south of Nunivak Island into northwestern Bristol Bay (Fay 1982; Mymrin et al. 1990; Garlich-Miller et al. 2011 USFWS 2017).

Although most walruses remain either in the Chukchi (for adult females and dependent young) or Bering (for adult males) Seas throughout the summer

months, a few occasionally range into the Beaufort Sea in late summer (Mymrin et al. 1990; Garlich-Miller and Jay 2000; USFWS 2017). Industry monitoring reports have observed no more than 38 walruses in the Beaufort Sea ITR geographic region between 1995 and 2015, with only a few instances of disturbance to those walruses (AES Alaska 2015, Kalxdorff and Bridges 2003, USFWS unpubl. data). The USGS and the Alaska Department of Fish and Game (ADF&G) have fitted between 30-60 walruses with satellite transmitters each year during spring and summer since 2008 and 2013 respectively. In 2014, a female tagged by ADF&G spent about 3 weeks in Harrison Bay, Beaufort Sea (ADF&G 2014). The USGS tracking data indicates that at least one tagged walrus ventured into the Beaufort Sea for brief periods in all years except 2011. Most of these movements extend northeast of Utqiagvik to the continental shelf edge north of Smith Bay (USGS 2015). All available information indicates that few walruses currently enter the Beaufort Sea and those that do, spend little time there. The Service and USGS are conducting multiyear studies on the walrus population to investigate movements and habitat use patterns, as it is possible that as sea-ice diminishes in the Chukchi Sea beyond the 5-year period of this rule, walrus distribution and habitat use may change.

Walruses are generally found in waters of 100 m (328 ft) or less where they utilize sea-ice for passive transportation and rest over feeding areas, avoid predators, and birth and nurse their young (Fay 1982; Ray et al. 2006; Rosen 2020). The diet of walruses consists primarily of benthic invertebrates, most notably mollusks (Class Bivalvia) and marine worms (Class Polychaeta) (Fay 1982; Fay 1985; Bowen and Siniff 1999; Born et al. 2003; Dehn et al. 2007; Sheffield and Grebmeier 2009; Maniscalco et al. 2020). When foraging, walruses are capable of diving to great depths with most dives lasting betw

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