1 National Science Foundation Office of Polar Programs Arlington, Virginia

Home , Backdoor Bay, McMurdo Ice Shelf, Williams Field

National Science Foundation Office of Polar Programs Arlington, Virginia

ENVIRONMENTAL DOCUMENT CONCURRENCE

Activity: Relocating Williams Field and Cleaning up the Current Location at McMurdo Station, Antarctica MCWF1801.IEE

I have read the attached document and concur with the findings and recommendation. I concur that the proposed activity can commence.

1 National Science Foundation Office of Polar Programs Arlington, Virginia

ENVIRONMENTAL DOCUMENT AND FINDING OF NOT MORE THAN MINOR OR TRANSITORY ENVIRONMENTAL IMPACT

Relocating Williams Field and Cleaning up the Current Location at McMurdo Station, Antarctica MCWF1801.IEE

FINDING

The U.S. Antarctic Program (USAP) proposes to relocate Williams Field. The airfield would be moved approximately 3.35 km from its existing location and therefore would be 14.6 km from McMurdo Station. The relocation would include cleaning up and closing the existing airfield.

The proposed action would include constructing two skiways and an apron and setting up the town site at the new location. In addition, the existing site would be cleaned up; structures, debris, and any residual spill material would be removed. Operations and maintenance of Williams Field were assessed in prior IEEs and no changes have been made to those proposed actions. Therefore, they are not part of this IEE.

Based on the analyses in the environmental document, the National Science Foundation (NSF) Office of Polar Programs (OPP) has determined that implementing the actions listed would not create more than a minor or transitory effect on the Antarctic environment, within the meaning of NSF's implementing requirements for the Protocol on Environmental Protection to the Antarctic Treaty. Therefore, a comprehensive environmental evaluation will not be prepared.

I recommend the activity proceed based on implementation of the proposed action. The proposed action provides for constructing and setting up the new Williams Field and closing the existing Williams Field. This proposed action is consistent with NSF's efforts to promote scientific investigation and provide for the safety of its participants, while protecting the Antarctic environment.

01/10/2018 ______1/11/2018 Recommending Official Date Recommending Official Date Polly Penhale Margaret Knuth Environmental Officer Manager, Operations Polar Environment, Safety and Health Antarctic Infrastructure and Logistics

National Science Foundation Office of Polar Programs Arlington, Virginia

ENVIRONMENTAL DOCUMENT AND FINDING OF NOT MORE THAN MINOR OR TRANSITORY ENVIRONMENTAL IMPACT

Relocating Williams Field and Cleaning up the Current Location at McMurdo Station, Antarctica MCWF1801.IEE

1.0! INTRODUCTION

The National Science Foundation (NSF) Office of Polar Programs (OPP) operates Phoenix Airfield and Williams Field, which are both located in the McMurdo Station area. United States Antarctic Program (USAP) aircraft provide essential logistical support by transporting personnel and cargo from Christchurch, New Zealand to McMurdo and then on to South Pole Station and field sites. Fixed-wing aircraft (including wheeled C-17, A- 319, B-757, and C-130 aircraft) use McMurdo area airfields for intercontinental flights, primarily during the austral summer (October through February). Intracontinental flights out of McMurdo Station (from Williams Field) are made by LC-130, Twin Otter, and Basler aircraft, which are equipped with both skis and wheels.

The existing Williams Field is located approximately 11.25 km from McMurdo Station, directly adjacent to the snow road to Phoenix Airfield, near milepost 5 (Figure 1). NSF/OPP proposes to relocate Williams Field. The new location would be approximately 14.6 km from McMurdo Station, placing it farther from the ice shelf edge and the Long Duration Balloon Facility (LDB). Relocation would require constructing two new skiways and establishing a new apron, aircraft refueling area, town site, and an access road. In addition, the existing Williams Field location would be closed and debris removed.

Since 2009, NSF/OPP has prepared four Initial Environmental Evaluations (IEEs) that describe McMurdo Station airfields (Table 1). These prior IEEs address construction and closure of select airfields and the operation of all airfields, including Williams Field. The proposed actions described in these IEEs are similar to the proposed action for the relocation of Williams Field. Therefore, the impacts described in these earlier IEEs are applicable to this proposed action.

Table 1. List of IEEs that address McMurdo Station airfields (NSF, 2017; 2015; 2014a; 2009) Date Title Document Number 1/26/2017 Establishing Phoenix Airfield Town Site and MCST1601.IEE.AM1 Closing Pegasus Airfield at McMurdo Station, Antarctica 8/21/2015 Alpha Site Runway Construction & Operation MCST1601.IEE

10/7/2014 Operate Airfield Facilities at McMurdo Station, MCST1001.IEE.AM1 Antarctica 11/17/2009 Operate a Single Airfield Facility at McMurdo MCST1001.IEE Station, Antarctica

Figure 1. Proposed location of the new Williams Field in relation to the current location (Figure is best viewed on-screen and enlarged)

2.0! PURPOSE AND NEED

Williams Field is located on the McMurdo Ice Shelf, which moves approximately 30 cm per day toward the ice shelf edge. The part of the shelf that reaches the edge collapses annually. Operations would be seriously affected if Williams Field is allowed to continue to move closer to the ice shelf edge. Therefore, Williams Field must be moved to ensure uninterrupted flight operations.

3.0! PROPOSED ACTION

The proposed action to relocate Williams Field would include constructing a new access road, two skiways, a refueling area, and an aircraft apron; relocating the town site; and cleaning up debris from the current Williams Field site (Figures 2 through 4). Relocation and construction activities would be initiated as early as January 2018 and completed by October 2018. Cleaning up the existing airfield would be completed by April 2019.

The design and dimensions of the new Williams Field (Figure 2) would be similar to the existing Williams Field. Approximately 7.7 km2 of snow surface would be compacted before moving equipment onto the site. Both the main skiway and crosswind skiway would be 3,000 m by 67 m (Figure 2). The apron and town site would be contained within a 275 m by 670 m area (Figures 3 and 4). The aircraft taxiway would be 300m by 50 m, and the access road would be approximately 3.35 km long and 30 m wide. These snow surfaces would be sheepsfooted and compacted using multiple passes and then groomed to a smooth surface.

Williams Field support facilities would include a cargo staging area, a fuel pit, a passenger terminal, an air operations building, a bathroom, storage buildings, and an aerospace ground equipment (AGE) storage building. Power would be supplied by on-site generators with wiring buried along the runway and apron and strung on poles at the town site. The power infrastructure would include approximately 735 m of aerial cable on 19 poles spaced approximately 39 m apart. In addition, approximately 1,860 m of trench would be dug to bury 4,400 m of cable. Aircraft operation systems would also be deployed, including a Microwave Landing System (MLS), a tactical air navigation (TACAN), a simplified short approach lighting on rails (SSALR), a precision approach path indicator lights (PAPI), runway end indicator lights (REILS), automated weather stations, and runway markers for day time operations.

It is anticipated the town site would support flight operations from October through February and would be set up and removed annually. All airfield structures would be mounted on skis or built on wooden supports so they can be moved and stored for winter. Other items, such as cargo containers (milvans), pallets, and waste storage boxes or drums may be placed on ski-mounted platforms or directly on the snow surface. ! The infrastructure at the current Williams Field (Figure 1) would be removed by April 2019. This infrastructure includes TACAN, MLS, and PAPI navigational aids; runway edge and lead-in markers on bamboo poles; and power poles and overhead power wiring.

6 Personnel would conduct a visual survey of the airfield to locate and remove any debris. Any snow discolored from past spills would be removed. All underground wiring (several thousand meters) would be abandoned in place. Overhead and underground wiring would be maintained until flight operations are completed.

All work associated with relocating Williams Field would be completed by existing staff and heavy equipment (dozers, tractors, sheepsfoot, landplane, etc.). Approximately 19,000 L of fuel would be required to prepare the site and move equipment and structures. ! 4.0! ALTERNATIVES TO THE PROPOSED ACTION

Under the proposed action alternative (Alternative A), Williams Field would be relocated to the new site and clean-up would occur at the current site.

4.1! Alternative B (No Action)

Under the No Action alternative (Alternative B), Williams Field would not be relocated to the new site. However, this alternative does not meet the purpose and need of the project and would not allow Williams Airfield to be used in the long-term.

4.2! Alternatives Considered but Not Analyzed

Two other sites were considered besides the proposed action site (Figure 1). Proposed location A was farther from McMurdo Station compared to the selected site and therefore would be less efficient to support, requiring more fuel and time to transport people, equipment, and cargo. Location C was not selected because of proximity to the existing snow road and to Phoenix Airfield, which could potentially disrupt operations at that airfield. !

Figure 2. Overview of proposed relocated Williams Field, including skiway, apron, and town site layout (Figure is best viewed on-screen and enlarged)

Figure 3. Details of the proposed Williams Field apron (Figure is best viewed on-screen and enlarged)

Figure 4. Details of the proposed Williams Field town site (Figure is best viewed on-screen and enlarged)

10 5.0! EXISTING CONDITIONS

5.1! Environmental Setting

The proposed new location of Williams Field is approximately 14.6 km from McMurdo Station, between the Long-Duration Balloon Facility (LDB) and Phoenix Airfield on the McMurdo Ice Shelf (Figure 1). The site is in a transition zone between snow accumulation and ablation (evaporation) regions. The winds in the area are variable, but the prevailing wind is generally from the east. There are no rock exposures in the vicinity. McMurdo Sound lies a few kilometers to the west. It is typically covered by seasonal sea ice that may extend approximately 40-50 km from McMurdo Station and may break up during the austral summer.

The proposed Williams Field site has a permanent and complete snow cover. The snow is underlain by a contiguous mass of glacial ice. Seasonal melting near the surface may occur during December and the first half of January, when relatively high temperatures and intense (24-hour) sunshine predominate.

The ice shelf at the proposed site is approximately 30 m thick. Depending on its temperature, crystallographic structure, and impurities, the ice has a flexural strength of 5 to 10 kg/cm2 (490 to 980 kilopascals), which is capable of supporting heavy wheeled aircraft (NSF, 2009).

5.2! Biota

Wildlife does not inhabit the airfield area, but occasionally transient skuas and other wildlife (e.g., seals or penguins) may be seen in the vicinity. Nearby McMurdo Sound is an important habitat for marine mammals and birds. Weddell seals, Adélie penguins, and emperor penguins are present in the area. Historically, seals and penguins have been affected by anthropogenic activities in the McMurdo vicinity, but current impacts are minimal (NSF, 2017; 2015; 2014a; 2009; 1991).

5.3! Antarctic Protected or Managed Areas

Several Antarctic Specially Protected Areas (ASPAs) are located in the region of McMurdo Station and Williams Field. Arrival Heights (ASPA 122) and Hut Point (ASPA 158) are next to McMurdo Station. The Northwest White Island (ASPA 137) is located approximately 10 km southeast of the proposed Williams Field relocation site. This ASPA contains an unusual breeding population of Weddell seals that has been physically isolated from other populations by the advance of the McMurdo and Ross Ice Shelves. Protective measures described in the ASPA Management Plan include entry and overflight restrictions. Cape Evans (ASPA 155), Cape Royds (ASPA 121), and Backdoor Bay (ASPA 157) are three ASPAs along the coast of Ross Island, over 15 km north of the proposed Williams Field site.

11 6.0! ENVIRONMENTAL ANALYSIS

This section of the IEE amendment identifies the potential environmental effects resulting from relocating Williams Field and cleaning up the existing site. Impacts related to the operation of the Phoenix Airfield were previously assessed (NSF, 2014a), as was the operation of multiple airfields in the McMurdo area (NSF, 2009). Relocating Williams Field would not alter the number or type of aircraft missions flown by the USAP.

Environmental impacts may result from physical disturbances, such as storing, handling, and using materials containing designated pollutants (5, fuel); the release of substances to the environment (air emissions); noise; effects on biota; and visual disturbances. Environmental releases or effects would not exceed what is currently delineated in the USAP Master Permit for an operating airfield.

6.1 Physical Disturbances

Physical disturbance to the environment is a certain outcome of relocating Williams Field and cleaning up the existing site. The disturbances would be from terrain alteration (grading and compacting snow surfaces), placing support structures, storing materials, and using fuel-powered equipment. The area affected would be approximately 7.7 km2.

Disturbances to the snow surface at the new site would be caused by constructing the skiways, apron, and town site, and by developing berms for winter storage of equipment and buildings. Removing structures, poles, and debris from the existing Williams Field would result in minor disturbances to the snow surface. In addition, the existing 9.5 km snow roadway from McMurdo Station to Williams Field would continue to be used and maintained routinely.

The extent of these physical disturbances is considered minor and localized in the context of the environmental setting and vast expanse of the McMurdo Ice Shelf. These physical changes would be surficial and continue to be visually apparent during the time the airfield is in operation. Should the airfield be decommissioned and removed in the future, snow will accumulate and return the area to a relatively undisturbed condition.

Physical disturbances may also result from meltwater generated by heating effects or solar gain due to the presence of the airfield, structures, equipment, and operations needed to maintain the facility. The USAP would implement measures to reduce the release of foreign substances (e.g., soot, dirt) that could accelerate the effect of solar heating during warm weather conditions. However, localized meltwater pools may form occasionally and require redistribution by pumping to prevent them from hindering aircraft operations. Meltwater effects at Williams Field, if any, are expected to be the same as at the current location. Therefore, the environmental effects resulting from managing meltwater at the airfield are expected to be minor.

12 6.2 Handling, Storage, and Use of Materials Containing Designated Pollutants

During the relocation of Williams Field, heavy equipment and other vehicles would be fueled using a day tank. This fuel would be the primary material containing designated pollutant constituents (i.e., hazardous substances) that would be stored and used at the airfield during set-up and closure. During set-up, the fuel would be stored in a day tank (38,000 L) or delivered via tanker truck.

Consistent with current USAP practices for airfield set-up and operation, best management practices (BMPs) would be consistently implemented to prevent the release of fuel and other materials containing designated pollutants to the environment. For example, during fuel transfer operations, personnel would continuously monitor the hose lines for leaks. Spill kits would be available to immediately clean up accidental spills.

Through the consistent use of BMPs, environmental impacts resulting from the use of materials containing designated pollutants are expected to be less than minor or transitory.

6.3 Releases to the Environment

Air Emissions Fuel combustion byproducts would be released to the air at Williams Field from heavy equipment, other vehicles, and the ancillary equipment used during set-up of the town site, TACAN, and MLS. Emissions were evaluated in the IEE “Operate a Single Airfield Facility at McMurdo Station, Antarctica” (MCST1001.IEE) (NSF, 2009). The quantity of emissions would be directly proportional to the volume of fuel consumed. Fuel combustion byproducts and fuel evaporative emissions would be estimated for all USAP facilities in the McMurdo Station area and reported for the Master Permit (NSF, 2014b).

Fuel combustion byproducts and evaporative emissions from equipment and ground vehicles at Williams Field during relocation and closure activities are expected to disperse rapidly in steady winds and dissipate in the atmosphere. The total volume of exhaust emissions from equipment used at the runways would be similar to the volume in past years for similar activities. Overall, the exhaust emissions are not expected to accumulate to levels that would alter the physical and chemical properties of the terrain or adversely affect local air quality. The effects of emissions are expected to be localized, less than minor, or transitory.

Operational Materials Limited materials may be released to the environment as a result of implementing the proposed action. These releases may include items such as wood, anchor pins, marker flags, or cables. Loss of irretrievable items (e.g., cables) is expected to result in minor or transitory impacts.

13 Accidental Releases Accidental releases typically involve unplanned events, such as spills, leaks, or the unintentional loss of equipment or materials, including items containing designated pollutants or wastes. Since accidental releases are not planned, their frequency, magnitude, composition, and resulting environmental effects cannot be projected. Appropriate BMPs would be used routinely to prevent the accidental release of fuel or other materials containing designated pollutants. These measures include the use of secondary containment and/or spill prevention devices during fuel storage and handling and spill detection monitoring during fueling activities. Spill kits and absorbent materials will be available at locations where fuel or other designated pollutants are handled and stored. Williams Field personnel will be trained in response actions and the proper use of spill kits.

If a liquid is accidentally released on the snow-covered ice shelf, the fate and transport of the material will depend on the environmental setting. Spilled liquid is expected to migrate vertically through the snow cover and spread laterally on the glacial ice, or it may accumulate in depressions on the ice (Christensen, 2008). There is no known pathway at the proposed or existing Williams Field for accidently released fuel to reach openings in the ice and migrate into the sea. The environmental effect of a fuel release on the ice shelf may be detectable on a long-term basis, in proximity to the release source, but the overall severity likely would be minimal. If a release occurs, cleanup procedures would be promptly implemented to remove contaminated media (i.e., snow and ice) to the maximum extent practical. Any impact resulting from an accidental spill is expected to be localized and minor. All spills would be documented and reported, consistent with the requirements of 45 CFR §671 and the USAP Master Permit. Therefore, impacts from accidental releases are anticipated to be less than minor or transitory.

6.4 Noise

Noise is a certain outcome of relocating Williams Field and closing the existing field. Sources of noise and vibrations include the mobile equipment (tracked and wheeled) required to perform the work. Construction noise sources would be small and short-term. Therefore, the effects from noise are expected to be less than minor and transitory.

6.5 Biota

With the exception of an occasional transient seal, penguin, or seabird, flora and fauna are not expected to be present at Williams Field. The nearest known sensitive biological communities are the seal colony in the Northwest White Island ASPA (ASPA 137), approximately 10 km away, and the penguin colony at Cape Royds (ASPA 121), over 15 km north of the proposed airfield site. Relocating Williams Field and closing the existing site is not expected to displace or disturb seals or penguins at the ASPAs or adversely affect the normal behavior patterns of any transient wildlife in the area.

Certain animals, particularly seals, are routinely present in the Scott Base land/ice-shelf transition zone and near cracks or openings in the seasonal sea ice. The Antarctic Conservation Act prohibits acts which may disturb or adversely affect these animals.

14 Transportation procedures and the existing McMurdo area roadways have been configured to mitigate adverse effects on the biota. Therefore, the proposed action is not expected to create disturbances that would displace animals or alter their behavior patterns. Therefore, impacts are anticipated to be less than minor or transitory.

6.6 Visual Characteristics

Aesthetic resources in Antarctica are not readily defined but can generally be characterized as the wilderness value, which encompasses an absence of permanent developments and/or visible evidence of human activity. The areas of the Antarctic continent that exist beyond established stations, support facilities, and research sites allow visitors to experience the remoteness of the continent and its unique landscapes, particularly those characterized by the sweeping glaciers and ice-free ridges, valleys, islands, and coastal regions.

Relocating Williams Field would result in the same impacts to the aesthetic wilderness value of this portion of the McMurdo Ice Shelf as currently experienced. Therefore, the effects are expected to be minor and transitory.

6.7 Indirect and Cumulative Effects

The proposed relocation of Williams Field, combined with the continued operation of Williams Field, Phoenix Airfield, and the LDB facility, would require logistical support from McMurdo Station. Relocating Williams Field and closing the existing site would result in a short-term increase in heavy equipment operation and labor hours. The traverse route leading from McMurdo Station to the shear zone would be realigned. Impacts would include:

•! using the roadway system between McMurdo Station and the airfields to transport flight crews, airfield support personnel, equipment, and supplies; •! maintaining the vehicle fleet needed to transport personnel, equipment, and supplies; and •! maintaining the roadway system needed to transport personnel, equipment, and supplies between McMurdo Station and the airfields (grooming, filling, compacting) Effective planning and resource management would be used to mitigate potential conflicts. Therefore, the indirect impacts on McMurdo operations from relocating Williams Field and closing the existing site are expected to be minor and transitory.

In addition to opening and operating the LDB facility, other activities that occur in the general area include preparation and staging activities for overland traverse. Thus, it is unlikely that the proposed action plus operation of Phoenix Airfield would have a significant cumulative effect on the environment. The cumulative effects of the activities, such as physical disturbances, would increase temporarily but would be localized to the runways, support facilities, and roads. Therefore, cumulative impacts are expected to be minor and transitory.

15 6.8 Summary

The potential environmental impacts associated with the proposed action to relocate Williams Field and close the existing site have been identified and evaluated in this IEE. Table 1 summarizes the potential environmental impacts that may result from these activities. Overall, the findings of this assessment indicate that the proposed action would provide an effective resource for ski-equipped aircraft at McMurdo Station while significantly avoiding disruptions associated with meltwater and other operational challenges.

Table 1. Summary of impacts resulting from the construction and set-up of the new Williams Field and closure of the existing Williams Field near McMurdo Station Environmental and Operational Impacts Overall Rating Affected Impact (see Activity Output Environment Duration Extent Intensity Probability note) Short- Localized Snow and Ice Low Certain 2 Physical term (7.7 km2) Disturbance Short- Biota Localized Low Unlikely 1 term Short- Air Emissions Air Localized Low Unlikely 1 term Releases Relocating Williams Long- (operational Snow and Ice Localized Low Unlikely 3 Field and closing the term materials) existing site Short- Noise Biota Localized Low Possible 1 term Alteration of Aesthetic & Wilderness Short- Certain Visual Localized Low 1 Values term (reversible) Characteristics Accidental Long- Snow and Ice Localized Low Possible 3 Releases (spills) term Indirect Effects Airfield Personnel; Short- & Cumulative McMurdo Station Localized Low Possible 2 term Impacts Operations Notes: + = environmental improvement; 0 = no substantial effect; 1 = minor, short-term effect; 2 = minor effect that continues for a limited period of time after the activity is completed; 3 = minor, localized long-term effect; 4 = environmental effects may be substantial or long-term

17 7.0 DOCUMENT PREPARATION SOURCES

Initial Environmental Evaluations Prepared by:

Dr. Ted Doerr, Staff, Environmental Engineering, ASC, [email protected]; ph: (720) 568-2041

Consultation:

Mr. Tim Briggs, Project Manager, Facilities Maintenance, and Constructiton, ASC [email protected]; ph: (720) 568-2425

Mr. Gary Cardullo, Manager, USAP Airfield McMurdo Station Antarctica, ASC, [email protected]; ph: (720) 568-2055

Dr. Kaneen Christensen, Manager, Environmental Engineering, ASC, [email protected]; ph: (720) 568-2235

18 8.0 REFERENCES

Christensen, K.E., 2008. Observations of fuel transport on sea ice from two fuel release events, with relevance to site assessment and closure, Cold Regions Science and Technology, 53:92-101.

NSF. 2017. Establishing Phoenix Airfield Town Site and Closing Pegasus Airfield at McMurdo Station, Antarctica. MCST1601.IEE.AM1. January 26, 2017.

NSF. 2015. Construct Alpha Airfield Facility at McMurdo Station, Antarctica. MCST1601.IEE. August 21, 2015.

NSF. 2014a. Operate Airfield Facilities at McMurdo Station, Antarctica. MCST1001.IEE.AM1. October 7, 2014.

NSF. 2014b. USAP Master Permit (ACA 2015-010). October 31, 2014.

NSF. 2009. Operate a Single Airfield Facility at McMurdo Station, Antarctica. MCST1001.IEE. November 17, 2009.

NSF. 1991. Supplemental Programmatic Environmental Impact Statement for the United States Antarctic Program. 1991.