Title : IEE, accelerated waste mgt, McM < Type : Antarctic EAM NSF Org: OD / OPP Date : October 17, 1991 File : opp93036 INITIAL ENVIRONMENTAL EVALUATION ACCELERATED IMPLEMENTATION OF WASTE MANAGEMENT ACTIONS AT MCMURDO STATION, ANTARCTICA October 17, 1991 Office of the Environment Division of Polar Programs National Science Foundation Washington, DC TABLE OF CONTENTS Page LIST OF ACRONYMS . . . . . . . . . . . . . . . . . . . . . . . iv 1. INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . 1 1.1 PURPOSE. . . . . . . . . . . . . . . . . . . . . . . 1 1.2 SCOPE. . . . . . . . . . . . . . . . . . . . . . . . 1 1.3 RELATIONSHIP TO OTHER ACTIONS. . . . . . . . . . . . 3 1.4 ASSESSMENT APPROACH. . . . . . . . . . . . . . . . . 4 2. REMEDIATION OF THE FORTRESS ROCKS DUMP . . . . . . . . . . 5 2.1 PURPOSE OF THE PROPOSED ACTION . . . . . . . . . . . 5 2.2 ALTERNATIVE ACTIONS. . . . . . . . . . . . . . . . . 6 2.2.1 Alternative 1þComplete Removal of Ground Surface Wastes. . . . . . . . . . . . . . . . . 6 2.2.2 Alternative 2þNo Action . . . . . . . . . . . 9 2.3 IMPACT ASSESSMENT. . . . . . . . . . . . . . . . . . 9 2.3.1 Alternative 1 . . . . . . . . . . . . . . . . 9 2.3.1.1 Release of contaminants during cleanup. . . . . . . . . . . . . . . . . . 9 2.3.1.2 Long-term release of contaminants. . . 11 2.3.1.3 Air quality and human health . . . . . 11 2.3.1.4 Logistics requirements . . . . . . . . 12 2.3.1.5 Aesthetics . . . . . . . . . . . . . . 13 2.3.2 Alternative 2 . . . . . . . . . . . . . . . . 13 2.3.2.1 Releases of contaminants during cleanup. . . . . . . . . . . . . . . . . . 13 2.3.2.2 Long-term release of contaminants. . . 14 2.3.2.3 Logistics requirements . . . . . . . . 14 2.3.2.4 Aesthetics . . . . . . . . . . . . . . 14 2.4 RECOMMENDED ALTERNATIVE AND RELEVANCE OF IMPACTS . . 15 2.4.1 Recommended alternative . . . . . . . . . . . 15 2.4.2 Relevance of Impacts. . . . . . . . . . . . . 15 3. DISPOSAL OF LIQUID WASTE DRUMS . . . . . . . . . . . . . . 16 3.1 PURPOSE OF THE PROPOSED ACTION . . . . . . . . . . . 16 3.2 ALTERNATIVE ACTIONS. . . . . . . . . . . . . . . . . 17 3.2.1 Alternative 1 (Nonhazardous Waste Disposal at McMurdo Station) . . . . . . . . . . . . . . 17 3.2.2 Alternative 2 (Disposal of All Wastes in the United States) . . . . . . . . . . . . 18 3.2.3 Alternative 3 (No Action) . . . . . . . . . . 19 3.3 IMPACT ASSESSMENT. . . . . . . . . . . . . . . . . . 19 3.3.1 Alternative 1 . . . . . . . . . . . . . . . . 19 3.3.1.1 Wastewater disposal. . . . . . . . . . 20 3.3.1.2 Logistics requirements . . . . . . . . 20 3.3.1.3 Hazardous spills . . . . . . . . . . . 21 3.3.1.4 Aesthetics . . . . . . . . . . . . . . 21 3.3.2 Alternative 2 . . . . . . . . . . . . . . . . 21 3.3.2.1 Wastewater disposal. . . . . . . . . . 21 3.3.2.2 Logistics requirements . . . . . . . . 22 3.3.2.3 Hazardous spills . . . . . . . . . . . 22 3.3.2.4 Aesthetics . . . . . . . . . . . . . . 22 3.3.3 Alternative 3 . . . . . . . . . . . . . . . . 22 3.3.3.1 Wastewater disposal. . . . . . . . . . 23 3.3.3.2 Logistics requirements . . . . . . . . 23 3.3.3.3 Hazardous spills . . . . . . . . . . . 23 3.3.3.4 Aesthetics . . . . . . . . . . . . . . 24 3.4 RECOMMENDED ALTERNATIVE AND RELEVANCE OF IMPACTS . . 24 3.4.1 Recommended Alternative . . . . . . . . . . . 24 3.4.2 Relevance of Impacts. . . . . . . . . . . . . 24 4. COMPLETION OF THE WASTEWATER OUTFALL . . . . . . . . . . . 25 4.1 PURPOSE OF THE PROPOSED ACTION . . . . . . . . . . . 25 4.2 AFFECTED ENVIRONMENT . . . . . . . . . . . . . . . . 26 4.2.1 Benthic Zones . . . . . . . . . . . . . . . . 26 4.2.2 Currents. . . . . . . . . . . . . . . . . . . 28 4.2.3 Ice and Wave Considerations . . . . . . . . . 29 4.3 ALTERNATIVE ACTIONS. . . . . . . . . . . . . . . . . 29 4.3.1 Alternative 1 (Discharge at 15 m) . . . . . . 29 4.3.2 Alternative 2 (Discharge at 5 m). . . . . . . 30 4.3.3 Alternative 3 (No Action: Surface Discharge). . . . . . . . . . . . . . . . . . . 31 4.4 IMPACT ASSESSMENT. . . . . . . . . . . . . . . . . . 31 4.4.1 Alternative 1 . . . . . . . . . . . . . . . . 31 4.4.1.1 Construction impacts . . . . . . . . . 32 4.4.1.2 Water quality impacts. . . . . . . . . 33 4.4.1.3 Safety . . . . . . . . . . . . . . . . 35 4.4.2 Alternative 2 . . . . . . . . . . . . . . . . 35 4.4.2.1 Construction impacts . . . . . . . . . 35 4.4.2.2 Water quality impacts. . . . . . . . . 35 4.4.2.3 Safety . . . . . . . . . . . . . . . . 36 4.4.3 Alternative 3 . . . . . . . . . . . . . . . . 37 4.4.3.1 Construction impacts . . . . . . . . . 37 4.4.3.2 Water quality impacts. . . . . . . . . 37 4.4.3.3 Safety . . . . . . . . . . . . . . . . 38 4.5 RECOMMENDED ALTERNATIVE AND RELEVANCE OF IMPACTS . . 38 4.5.1 Recommended Alternative . . . . . . . . . . . 38 4.5.2 Relevance of Impacts. . . . . . . . . . . . . 40 5. RECOMMENDATIONS. . . . . . . . . . . . . . . . . . . . . . 41 5.1 REMEDIATION OF FORTRESS ROCKS. . . . . . . . . . . . 41 5.2 REMOVAL OF LIQUID WASTE DRUMS. . . . . . . . . . . . 41 5.3 COMPLETION OF THE WASTEWATER OUTFALL . . . . . . . . 41 6. REFERENCES . . . . . . . . . . . . . . . . . . . . . . . . 43 APPENDIX A SAMPLING AND ANALYSIS METHODS FOR DISPOSAL OF LIQUID WASTE DRUMS . . . . . . . . . . . . . . . . 44 LIST OF ACRONYMS ANL Argonne National Laboratory ASA Antarctic Support Associates, Inc. ATCM Antarctic Treaty Consultative Meeting BOD biochemical oxygen demand DO dissolved oxygen DRMS Defense Reutilization and Marketing Service IEE Initial Environmental Evaluation NSF National Science Foundation NSFA Naval Support Force Antarctica RCRA Resource Conservation and Recovery Act SEH Safety, Environment, and Health SEIS Supplemental Environmental Impact Statement USAP United States Antarctic Program USEPA U.S. Environmental Protection Agency 1. INTRODUCTION 1.1 PURPOSE This assessment considers the environmental impacts of three waste management actions proposed for implementation during the 1991þ92 austral summer season at McMurdo Station, Antarctica (Fig. 1). McMurdo Station is the main research and logistics support base of the United States Antarctic Program (USAP), which is managed by the National Science Foundation (NSF). This assessment will be used by USAP decisionmakers in determining whether further environmental review and documentation is needed for any of the proposed actions. The need for the waste management actions assessed in this document was identified during implementation of the USAP Safety, Environment, and Health (SEH) Initiative. This assessment has been prepared to comply with Executive Order 12114 ("Environmental Effects Abroad of Major Federal Actions", January 4, 1979), and with Antarctic Treaty Consultative Meeting (ATCM) Recommendation XIV-2 ("Man's Impact on the Antarctic environment: Environmental impact assessment"). This assessment constitutes an Initial Environmental Evaluation as described in ATCM Recommendation XIV-2. The USAP's materials and waste management efforts are consistent with ATCM Recommendation XV-3 ("Human Impact on the Antarctic Environment: Waste Disposal"). 1.2 SCOPE The scope of this assessment includes waste management actions that are scheduled for accelerated implementation during the 1991þ92 austral summer season. The three actions are: Fig. 1 Cleanup of asbestos-containing wastes and ground surface debris at Fortress Rocks. During the 1990þ91 austral summer season, asbestos was discovered at the Fortress Rocks dump. NSF decided to cease open burning and disposal of waste at the site. The purpose of this action is to minimize the potential release of fibers from asbestos-containing wastes that have been identified at the area while removing ground surface debris. Disposal of Liquid Waste Drums. Approximately 800 steel drums of liquid waste have accumulated at McMurdo Station. Many of the drums have unknown contents. Most are assumed to be petroleum containers that have been reused as human waste receptacles. Although completely frozen, these drums present potential safety, human health and environmental risks. The purpose of the proposed action is to identify the contents of these drums and properly transport them and their contents to the United States for disposal. Currently, new drums or old drums that have been cleaned are properly labeled and used as human waste containers. Completion of the Wastewater Outfall. In the past, McMurdo Station's wastewater was discharged to McMurdo Sound through a surface outfall. A submerged outfall was constructed during the 1989þ90 and 1990þ91 seasons but was destroyed by strong wave action in February 1991. A decision was made to re-evaluate the outfall's design and its environmental impact potential before complete reconstruction. The purpose of the proposed action is to install a practical and environmentally-beneficial wastewater outfall. 1.3 RELATIONSHIP TO OTHER ACTIONS The NSF recently completed a Supplemental Environmental Impact Statement (SEIS) evaluating environmental impacts of programmatic activities of the USAP. A Draft SEIS was published in December 1990, and the Final SEIS is expected to be published in October 1991 (NSF 1991a). The preferred alternative considered in the SEIS is to proceed with the SEH initiative, using applicable U.S. environmental requirements as guidelines. The need for the waste management actions considered in this assessment was identified in the SEIS. This assessment is tiered to the broad treatment of waste management contained in the SEIS and provides additional information and a more detailed assessment to support specific decisions on the three actions under consideration. The environmental impacts of the original wastewater outfall design have also been assessed previously by NSF (NSF 1989). That earlier assessment was conducted without much of the data needed to evaluate impacts of the outfall. This assessment, therefore, supplements and supersedes the 1989 assessment. The cessation of waste disposal at Fortress Rocks was accompanied by the installation of a temporary incinerator during the austral winter of 1991 and by the proposed installation of an interim incineration system during the 1991þ92 austral summer season. Installation of the temporary incinerator and the proposed interim incineration system are related waste management actions that are addressed in separate environmental assessments (NSF 1991b, 1991c, 1991d). 1.4 ASSESSMENT APPROACH The steps that have been used in this IEE to assess the environmental impacts of each proposed waste management action and its reasonable alternatives are as follows: Identification of the purpose of the proposed action. The objective of the action is described so that feasible alternative ways of meeting the objective can be considered. Definition of alternative actions. Reasonable alternative ways of implementing the proposed waste management action are defined. Identification of the potential impacts of each alternative. Impacts are identified, to the extent possible, by describing: þ sources of pollutants; þ pathways followed by pollutants when released from their source; þ receptors (organisms, ecosystems, or other environmental resources) that could be exposed to pollutants released from their sources; þ the effects of pollutants on such receptors; and þ comparison of the potential impacts of the alternatives. (Contrasting evaluation is undertaken with the intent of identifying the most environmentally favorable and feasible alternative). 2. REMEDIATION OF THE FORTRESS ROCKS DUMP 2.1 PURPOSE OF THE PROPOSED ACTION The purpose of this proposed action is to remediate asbestos contamination at the Fortress Rocks site and to minimize the potential release of asbestos fibers. In addition, it is proposed to remove all readily-accessible ground surface wastes. Asbestos-containing wastes were discovered recently among the solid wastes (i.e., scrap metals, wall board, cardboard, residual ash from prior waste burns, and other residues) from past uses of the site for solid waste management. The proposed action is intended to remove all ground surface wastes as well as all of the asbestos-containing and asbestos-contaminated wastes from the site. The Fortress Rocks site was developed as a waste disposal area in the early 1980s to replace the previous practices of dumping solid waste at the edge of the sea ice in the vicinity of Winter Quarters Bay and staging of wastes on the sea ice surface of McMurdo Sound (for eventual disposal in deep water when the sea ice broke apart). Various solid wastes were dumped at designated sites within the Fortress Rocks waste disposal area. Combustible wastes (i.e., food wastes, food-contaminated wastes, domestic wastes, paper, and scrap lumber and cardboard) were burned (combustion was facilitated with unusable, waste fuels) and the resultant ash was compacted. Such noncombustible wastes as scrap metal, wall board, tires, batteries, aerosol cans and high density plastics) were stored prior to retrograding to the United States. Additional information on past operation of Fortress Rocks is available in Reed and Sletten (1989). During the 1990þ91 season, an environmental measurements program conducted for the USAP indicated the presence of friable asbestos in the wastes at the Fortress Rocks site, particularly among the waste scrap metal. Because asbestos could present a health hazard to workers at the site (and possibly to station personnel, in general), the decision was made to terminate use of the Fortress Rocks site as a solid waste management area. Instead, the following interim solid waste management practices have been implemented. Continued and increased minimization and recycling of wastes. Increased interim storage, and retrograding, of noncombustible wastes on the annual supply ship. Incinerating a backlog of food-contaminated wastes, using carefully limited amounts of such materials as clean cardboard and scrap wood to facilitate combustion of wet waste. A temporary incinerator was constructed at McMurdo Station for this purpose during the 1991 winter season. Disposal of the remainder of this backlog of food wastes, if feasible, in a proposed commercial, high-temperature, interim incineration system fitted with emissions controls and monitors. Initiation of this step is planned for the 1991þ92 austral summer season. USAP continues to investigate options for the remediation of the entire Fortress Rocks site. The potential for release of contaminants other than asbestos is being studied, and the need for possible additional remediation of such contaminants is weighed under all of the alternatives considered in this document. 2.2 ALTERNATIVE ACTIONS The objective of this action is to remove asbestos materials and all loose wastes from the surface of the dump. For purposes of this assessment, therefore, only two alternatives are considered: the proposed action and the no-action alternative. Since studies to determine the extent of other potential contaminants at the site are underway, but have not been completed, final remediation and closure dates of the site cannot yet be designated. Additional assessment may be required if the need for additional remedial action at Fortress Rocks is identified. 2.2.1 Alternative 1þComplete Removal of Ground Surface Wastes This alternative would include: removing all accumulated ground surface wastes at the site such that no significant asbestos contamination remains and potential contamination from other pollutants is reduced--allowing future site characterizations and remediation, where necessary; segregation of nonhazardous wastes from those containing asbestos and other contaminants identified, to date; incineration of nonhazardous food wastes as described above in either the temporary incinerator or in the proposed interim incineration system, if feasible; preparation and packaging of all asbestos-contaminated and all noncombustible wastes for immediate transport to the United States for proper disposal or recycling; and installation of a ground surface barrier. Much of the known asbestos is attached to such bulky scrap metal items as pipe and boiler parts. These surface materials would be removed, decontaminated, and retrograded to the United States for disposal. Partially buried scrap that has asbestos attached would be cut off at a depth of approximately 15 cm (6 in.) below the ground surface. Contaminated soil would neither be excavated nor collected, as U.S. Department of Agriculture regulations may not allow antarctic soil to be brought into the United States. A temporary waste staging area in compliance with U.S. hazardous waste regulations would be used to prepare, segregate, label and package all wastes. These activities will take place at a location currently used for materials storage (the graded pad lying on the south side of the McMurdo to Scott Base Road, approximately 1000 feet West of Building 186). Such an area is needed due to the inadequate number of empty containers (i.e., milvans and flatracks) on station--volume reduction is necessary to facilitate removal. This area will function as a processing center for demolition debris consolidation, size reduction and containerization. It will provide working space for the containerization of unconsolidated scrap metal. These properly containerized and labeled wastes will be transferred to the annual supply vessel for retrograde from Antarctica. All other open spaces at McMurdo Station were considered for locating the temporary waste staging area. The proposed location, however, is the only available and flat area of sufficient size that can be used without affecting other operations. The staging area will be delimited by flatracks to fully contain operations. At the conclusion of the removal operation the staging area will be completely cleared of any residuals, and the loaded flatracks will be transported to the annual supply vessel for backloading as retrograde cargo. Since asbestos is considered a hazardous air pollutant rather than a hazardous waste, it would also be handled pursuant to the Clean Air Act's National Emission Standards for Hazardous Air Pollutants. Monitoring and control measures, based on U.S. regulations (i.e., applicable Occupational Safety and Health Act workplace standards), would be conducted throughout the cleanup to protect workers and the environment from exposure to harmful levels of potential pollutants; or from further contamination of the environment. Antarctic Support Associates, Inc. (ASA), the USAP's civilian support contractor, first estimated the volume of waste that would need to be removed under this alternative would be about 7,000 cubic yards; more recent estimates by AECOM, Inc. (the subcontractor that would conduct the waste removal) recognized that there were many voids in the accumulation of wastes and revised the estimate to about 2,000þ3,000 cubic yards of waste. Most of the waste is expected to be nonhazardous. Extensive personnel, equipment, and logistic support are known to be required. USAP contractors estimate the following equipment would be needed to accomplish this task (Table 1). Table 1. Estimated equipment required for removal of ground surface wastes. Equipment Weight kg (lbs) Scrap metal baler Track loader Lift truck Skid steer loader Decontamination trailer Tractor Pickup truck Trailer Utility vehicle Milvans (6) of supplies Total weight: 27,000 (59,000) 19,000 (42,000) 37,000 (81,000) 4,000 (9,000) 5,000 (10,000) 9,000 (20,000) 3,000 (6,000) 7,000 (16,000) 2,000 (5,000) 54,000 (120,000) 167,000 (368,000) Because this equipment is needed at the start of the 1991þ92 season, it must be transported to New Zealand by surface vessel and to McMurdo Station by aircraft. At least three flights by C-5 and 10 flights by C-141 aircraft between New Zealand and McMurdo would be needed for this equipment and the equipment needed for disposal of liquid waste drums (Sect. 3.2). Eight people would work at the landfill on two shifts throughout the season. This phase of the Fortress Rocks remediation would need to be completed during the 1991þ92 season. After completion of waste removal from the Fortress Rocks area, and after an industrial hygiene inspection by ASA personnel, an 80-mil thick, high density polyethylene (HDPE) barrier will be placed over the area. Prior to securing the HDPE barrier, the area will be graded using heavy equipment to prepare the site for coverage. This relatively flat surface will be required to assure that the liner sections can be seamed effectively. The HDPE liner, available in 22.5 foot wide rolls, will be stretched over the area and secured at its perimeter with sandbags loaded with locally obtained earth fill material. Also, sandbags will be placed upon the liner to hold it in place. 2.2.2 Alternative 2þNo Action Under Alternative 2, as under Alternative 1, USAP's investigation of the extent of contamination at the site would continue. The identified need to cleanup such other contaminants could occur under this alternative. 2.3 IMPACT ASSESSMENT Impacts of the proposed cleanup at Fortress Rocks could include the release of contaminants during the cleanup, the continued release of contaminants following cleanup, and impacts of the transportation and logistics required for the cleanup. Environmental benefits to air quality and aesthetics as well as human health could occur. 2.3.1 Alternative 1 This alternative involves removal of asbestos and all ground surface wastes from Fortress Rocks. 2.3.1.1 Release of contaminants during cleanup Cleanup of the site would include removing ground surface wastes, identifying asbestos and other contaminants, removing asbestos attached to wastes, and properly containing all the wastes. Asbestos removal would be done within a special facility designed to contain fibers. Such factors as strong winds, difficulties in extracting materials from the frozen site, and the difficulties of working in cold weather could contribute, however, to the accidental release of asbestos. If released from the site, asbestos fibers could be transported by wind. Winds at McMurdo are frequently from the east (Fig. 2) and could carry the fibers from Fortress Rocks toward the center of the station. The impacts of such releases on health of station residents would depend on the amount of asbestos released and the degree to which it is dispersed in the wind. Any such exposure would be short term, lasting only until the asbestos is controlled or winds change. Fig. 2 Wastes other than asbestos could be released from the site. The cleanup would require use of heavy machinery to extract materials. It is possible that containers of hazardous material (e.g., old drums containing fuel, solvents, or laboratory chemicals) are buried at the site and could be punctured during the cleanup. Because only visible surface materials would be removed from the site, the risk of such accidental releases would be much less than if all of the dump residues were to be removed. Although studies of potential contaminants at the Fortress Rocks site are underway, characterization of the waste present at the site has not been sufficiently completed to predict what other hazardous or toxic contaminants might be released. Natural resources that could be affected by any non-asbestos releases during cleanup include birds (mainly South Polar skuas) that might feed on exposed waste staged temporarily at the site. Should sufficient surface runoff from snowmelt pass through the site after contaminant releases occur (and before cleanup is effected), such contaminants might also be transported to Winter Quarters Bay. Any such releases, however, are expected to be minor compared with existing contamination in the bay (e.g., Lenihan et al. 1990). 2.3.1.2 Long-term release of contaminants Alternative 1 would leave most residues of past waste disposal (i.e., below ground surface wastes) in place at the site. These wastes would remain in place unless additional study or other management considerations resulted in a decision for their removal. This alternative would pose some risk of future releases. Such releases would be most likely in the unusual event that warm weather caused melting of some of the frozen, liquid contaminants as well as high surface water runoff through the site. The potential for long-term releases would be no greater than under existing conditions. Existing levels of such contamination are currently being studied, and the need for additional remedial actions will be addressed as needed in future environmental reviews. 2.3.1.3 Air quality and human health The potential transport of existing asbestos contamination by air (e.g., wind-blown contaminated materials) at Fortress Rocks may pose a health risk to station residents. Measurements taken at the site indicate that workers in the immediate vicinity of the dump should wear protective equipment to avoid potential risks. Alternative 1 would have the positive impact of eliminating such risks in the long term. After the proposed cleanup is completed, any concentrations of airborne asbestos fibers are expected to be at levels where human health risks at the site are negligible. 2.3.1.4 Logistics requirements Removal of all ground surface wastes at Fortress Rocks would require major logistics support (e.g., the equipment requirements listed in Sect. 2.2.1). At least three additional C-5 and 10 additional C-141 round trips between McMurdo and New Zealand would be required to move equipment sufficient to start work during the 1991þ92 summer season. Follow-up transport would be done by ship. It is estimated that eight additional people would be needed for a full austral summer season. Ship and air transport of equipment needed for this effort from the United States to McMurdo is estimated to cost $1.8 million (personal communication, MAJ Sonia Gaidelis, Terminal Operations Officer, Naval Support Force Antarctica, with Steve Railsback, Oak Ridge National Laboratory, August 12, 1991). The three additional C-5 and ten additional C-141 flights required to transport equipment from New Zealand to McMurdo for this alternative would consume about 390,000 l (100,000 gallons) of fuel (personal communication, LT Keith Foreman, Fuels Officer, Naval Support Force Antarctica, with Steve Railsback, Oak Ridge National Laboratory, August 14, 1991). These figures also include transportation of equipment for removal of liquid waste drums (Sect. 3); the transportation impacts of these two actions cannot be separated readily. These requirements may divert logistics support from other USAP efforts more directly related to the conduct of science. The estimated maximum of 2,000þ3,000 cubic yards of wastes would be transported, along with the equipment, back to the United States aboard the annual supply vessel. The impacts of such logistics operations at McMurdo Station are described in the SEIS (NSF 1991a). The transport and support requirements for this alternative could be offset at least partially by postponing other activities at McMurdo Station for the period required to complete the cleanup. Either science projects or other support activities (e.g., completion of the new science building) could be postponed. Such postponement would have detrimental effects on the USAP's principal mission, the conduct of antarctic science. 2.3.1.5 Aesthetics There would be clear benefits to aesthetics from completely removing ground surface wastes from Fortress Rocks. Although obscured from view from most of the McMurdo vicinity, the dump is not visually appealing. This alternative would improve the aesthetics of this small area. The temporary waste staging area proposed for preparing, segregating, labeling and packaging all ground surface wastes from Fortress Rocks will be designed to mitigate aesthetic impacts. The temporary staging area will be delimited by flatracks aligned end to end to form an enclosure. An opening on one side will provide access to the enclosure created by such alignment. The opening will be visually shielded with additional flatracks such that work within the area will not be visible to passersby. A potential concern with Alternative 1 is that the disposal of wastes in the United States may be difficult if not properly planned or coordinated, or not subjected to prior certification and pre-acceptance by the waste receiver. Although disposal would be arranged before the waste was extracted, unforseen circumstances could result in an inability to unload and dispose of the wastes. The large volume of waste to be retrograded under this alternative make potential regulatory problems with disposal more likely. The Naval Support Force Antarctica (NSFA), which is responsible for planning and coordinating disposal in the United States, is working to finalize a mechanism for disposal. NSFA has requested that the Defense Reutilization and Marketing Service (DRMS) in Battle Creek, Michigan, develop a turn-key contract for disposal of the wastes. The turn-key contract will contain provisions for explicit receiver specification of the level of chemical analysis required for waste transport to the United States, waste acceptance in the U.S. as well as provision for receiver pre-acceptance of the wastes at McMurdo Station. These mechanisms are intended to ensure that the wastes can be transported, unloaded and disposed of properly. 2.3.2 Alternative 2 Alternative 2, the no-action alternative, would not include remediation of Fortress Rocks. No impacts of remediation would occur, but long-term releases of asbestos would continue. 2.3.2.1 Releases of contaminants during cleanup Because no cleanup would occur under this alternative, no releases from the disturbance of wastes would occur. 2.3.2.2 Long-term release of contaminants Existing releases of asbestos would continue under this alternative. Measured airborne concentrations of asbestos indicate that a human health risk would continue. Measurements made by the ASA during the 1990þ91 season indicate that airborne concentrations when the asbestos is not being disturbed can be at levels where protection of workers is recommended. Any disturbance of the asbestos-containing areas must be expected to result in concentrations exceeding permissible exposure limits. Restricted access to the area would be needed to avoid health effects. The potential for future releases of non-asbestos contaminants would be the same under alternatives 1 and 2. The site's wastes would remain, and a potential for long-term releases would exist. However, should the continuing investigations of the site indicate that the release of contaminants other than asbestos require remediation, such remediation could take place. Studies quantifying the types and amount of long-term releases from the site are underway but have not been completed, to date. 2.3.2.3 Logistics requirements The no-action alternative would not require the transport of equipment, personnel, and retrograded materials between the United States and McMurdo Station. No effects of such transport on science support would occur. However, support activities at McMurdo would be affected by the long-term unavailability of the Fortress Rocks area, which would be off limits. Solid waste handling (e.g., sorting and packaging of recyclable materials) that has occurred there in the past would be permanently relocated. 2.3.2.4 Aesthetics The Fortress Rocks site would continue to have a negative aesthetic impact. As this area is small and hidden from most of the rest of the station, this impact would be relatively minor. 2.4 RECOMMENDED ALTERNATIVE AND RELEVANCE OF IMPACTS 2.4.1 Recommended alternative The main purpose of the proposed action is to remove ground surface wastes and to preclude the hazards of asbestos releases from the former Fortress Rocks site. Because studies of the site have shown that asbestos may pose a hazard to the health of McMurdo staff, remediation of this hazard is appropriate. Studies of other potential contaminants at the site are underway but, to date, have not identified the need for other remedial actions. Given these considerations, Alternative 1 is recommended. This alternative would remediate the known asbestos hazard, and would pose no significant barriers to additional study or cleanup of the site. 2.4.2 Relevance of Impacts The cleanup of asbestos at Fortress Rocks would be an important human health and environmental benefit of this action. The main impacts of the proposed remediation result from transportation of the equipment and dump residues to and from McMurdo Station. The additional transportation requirements would be a small increase above routine USAP operations. For example, at least 13 air transport flights would be needed for the proposed action (Sect. 2.3.1.4). During the 1990þ91 season, a total of 122 such flights were made. The environmental impacts of the air transport requirements have been considered in the SEIS (NSF 1991a). 3. DISPOSAL OF LIQUID WASTE DRUMS 3.1 PURPOSE OF THE PROPOSED ACTION The purpose of this proposed action is to dispose of approximately 800 liquid waste drums that have accumulated at McMurdo Station. The actual content of these drums is unknown, although most are believed to contain human waste. Field camps are required by USAP policy to contain all wastes and return them to McMurdo for disposal or retrograding. These camps often use drums to contain human wastes and other wastewater. In addition, several buildings at McMurdo are not connected to the sanitary wastewater system. At such buildings, drums are used to collect human wastes. As a result of these practices a large number of drums, known as "U-barrels", containing human wastes have accumulated at the station. These drums are stored outdoors and normally remain frozen. In the long term, however, they may be a source of unexpected contaminants, and their presence contributes to an adverse aesthetic impact to the area. In the past, emptied supply drums were reused as U-barrels. These drums originally might have contained oil, fuel, or other substances that are hazardous or otherwise unsuited for wastewater disposal. Until recent years there was no control over how thoroughly the drums were emptied or cleaned before reuse as U-barrels. The accumulated drums must be considered, therefore, as potentially containing hazardous materials. Their human wastes content can also present a health risk to USAP personnel. Current practice at McMurdo is to use new plastic drums as U-barrels. Procedures for properly reusing steel drums and for disposing of the contents of U-barrels are being developed. 3.2 ALTERNATIVE ACTIONS Steps that must be taken to dispose of the accumulated drums are: sample each drum, chemically analyze its contents (for both transportation and acceptance purposes), determine whether the contents are classified either as nonhazardous wastewater or as hazardous waste, and properly label each drum; treat and dispose of the drums' contents as either nonhazardous or hazardous waste; and dispose of the containers. Shipping the drums without sampling them to determine if they are hazardous would violate U.S. and international transportation regulations and is, therefore, not considered an alternative to the proposed action. Drum contents that are found to contain only human waste could be disposed of at McMurdo or retrograded to the United States for disposal. Any contents found to be hazardous must be transported to the United States as hazardous waste for disposal. The drums themselves could be disposed of as solid waste in the United States, recycled in the United States, or reused in Antarctica, dependant upon initial contents. Alternatives 1 and 2 differ on whether non-hazardous human waste would be disposed of at McMurdo or retrograded. 3.2.1 Alternative 1 (Nonhazardous Waste Disposal at McMurdo Station) The first alternative would result in nonhazardous drum contents being disposed of at McMurdo. Drums would be sampled and their contents analyzed at McMurdo to determine whether the contents are hazardous. This analysis of each drum would require the following steps. Sampling the contents of each drum. This would be done by taking a core of its frozen contents. Analysis of the sample to determine whether it is hazardous according to the Resource Conservation and Recovery Act (RCRA) hazardous waste regulations. A series of analyses would be required to determine whether the drum contents must be considered hazardous waste under the RCRA criteria. If a drum is found to contain no hazardous waste, then its contents would be thawed and disposed of to the McMurdo wastewater system. Traces of oil could be removed with a gravity separator. The drum itself would be cleaned and disinfected and either retrograded to the United States or reused. Before return to the U.S., drums would be stored temporarily at the existing hazardous waste storage area at McMurdo Station. If a drum is found to contain hazardous waste, it would be packed inside a new container ("overpacked"), properly labeled, and shipped to the United States in compliance with Department of Transportation requirements. In the United States, such drums would be handled under terms of the turn-key contract negotiated by NSFA (Sect. 2.3.1). The drums and their contents would be disposed of at a licensed hazardous waste disposal facility, in accordance with U.S. regulations. Alternative 1 would have equipment and supply requirements similar to those described below for Alternative 2. The number of drums requiring retrograde to the United States is expected, however, to be lower under Alternative 1. If, however, most of the emptied drums are retrograded for recycling in the United States instead of reuse at McMurdo, the transportation requirements would be similar to those of Alternative 2. More laboratory equipment and personnel would be required at McMurdo as many tests would be required to determine if each drum meets the complex hazardous waste definitions. 3.2.2 Alternative 2 (Disposal of All Wastes in the United States) Under this alternative, all drums would be retrograded to the United States for disposal. The procedures for disposing of drums and their contents under Alternative 2 are as follows. A core sample of each drum's contents would be obtained. The sample would be analyzed only to determine whether it is hazardous under transportation regulations. The analysis requirements would be less extensive than the RCRA requirements used under Alternative 1. Sampling and analysis methods are shown in Appendix A. All drums would be overpacked, labeled for shipment (including any transportation hazard labels), temporarily stored at the existing hazardous waste storage area at McMurdo Station, and then retrograded on the annual supply vessel. All drums would be disposed of in the United States under the turn-key disposal contract (Sect. 2.3.1) and in accordance with state and federal regulations for wastewater and hazardous waste. Additional analysis or treatment of the wastes would be conducted if required. Equipment for repacking, and transporting the drums would be shipped to McMurdo by air. ASA, AECOM, Inc., and NSFA estimate that the equipment shown in Table 2 and about 800 overpack drums would be required (in addition to equipment and supplies used for remediation of the Fortress Rocks area; see Sect. 2.2). Table 2. Estimated equipment required for repacking, and shipment of drums. Equipment Weight kg (lbs) Backhoe Lift trick Skid steer loader Pickup truck Total weight: 7,000 (15,000) 4,000 (8,000) 3,000 (7,000) 3,000 (6,000) 16,000 (36,000) 3.2.3 Alternative 3 (No Action) Under this alternative, there would be no sampling, analysis, or disposal of the waste-filled drums. The drums would remain in a storage yard at McMurdo for the lifetime of the station. The storage yard would be fenced and the drums would occasionally be inspected for leakage. Should McMurdo Station ever be closed, disposal decisions regarding the disposition of such waste would be made at the time of closure. If the drums were in the United States and if any of the drums contain wastes defined as hazardous under RCRA, their continued storage at the site would be contrary to RCRA regulations. The USAP is not bound by such regulations but attempts to follow them as a management policy (NSF 1991a). 3.3 IMPACT ASSESSMENT Few environmental impacts are expected from disposal of the drums. Disposal of nonhazardous drum contents at McMurdo would add to the wastewater discharge. Additional transportation and logistics impacts would occur. Risks of hazardous material spills would be minor under each alternative except the no-action alternative. 3.3.1 Alternative 1 Alternative 1 involves disposal of nonhazardous drum contents at McMurdo, with the need to retrograde fewer drums. 3.3.1.1 Wastewater disposal It is expected that the contents of many of the drums will be found to be nonhazardous. They may be disposed of, therefore, at McMurdo, following such treatment as gravity separation to remove traces of oil. The non-petroleum product or non-hazardous component of these drums contents would be disposed of to the wastewater system. To estimate the maximum likely impacts to the marine ecosystem at McMurdo, it is assumed that all of the about 800 drums contain about 200 L (53 gal) of nonhazardous sewage waste and would be emptied into the wastewater system. This would be an additional load of about 150,000 L (39,750 gallons) of raw wastewater. McMurdo Station typically discharges about 230,000 L (60,000 gal) a day during the austral summer season. Disposal of 150,000 L of drum contents over, for example, a two-week period would increase the volume of wastewater discharged by approximately 5 percent. The drum contents are assumed to have higher concentrations of organic matter and nutrients than the rest of the wastewater, so the strength of the wastewater, as well as the volume, would slightly increase. The effects of McMurdo Station's wastewater discharge (Sect. 4.4), which include local depression of dissolved oxygen, enriched nutrient concentrations, and deposition of organic solids on the bottom, would be temporarily and slightly increased under this alternative. In addition, cleaning the drums for reuse or recycling would produce additional wastewater loads. It must be noted that currently there exists no facility at McMurdo Station through which any non-hazardous waste can be introduced into the wastewater system or where empty drums can be cleaned for reuse or retrograde. 3.3.1.2 Logistics requirements Under Alternative 1, it is assumed that many of the drums would not require transportation to the United States for disposal. However, because transportation via the annual resupply ship requires relatively little additional cost, the avoided transportation costs would be relatively minor. It is likely that many of the drums emptied at McMurdo would be retrograded to the United States for recycling anyway, further reducing the difference in transportation requirements between alternatives 1 and 2. A second logistic consideration is that drum handling equipment, and additional laboratory equipment and personnel would be required at McMurdo Station under this alternative. The 16,000 kg (36,000 lb) of equipment described in Sect. 3.2 for Alternative 2, plus additional laboratory equipment, would require air transportation to McMurdo at the beginning of the 1991þ92 season. This requirement, plus transportation requirements for remediation of the Fortress Rocks dump (Sect. 3) would result in an estimated 13 additional C-141 and C-5 flights. These additional flights will consume fuel, release air emissions, and potentially displace support for other projects more directly related to the support of scientific research. The equipment would be returned to the United States aboard the annual resupply ship. To comply with RCRA regulations (an NSF management policy), the drum contents could not be disposed of without ensuring that they do not contain hazardous wastes. Under Alternative 2, analysis would be conducted only to determine if wastes present transportation hazards, as defined by U.S. Department of Transportation regulations. The laboratory analysis requirements to determine whether the waste is hazardous under RCRA are much more extensive than are the requirements to determine transportation hazards. Alternative 1 would require more laboratory resources, therefore, than the other alternatives. Such equipment and supplies, and personnel would be transported to McMurdo via air specifically for this project. 3.3.1.3 Hazardous spills There would be little risk of hazardous material or waste spills under this alternative. Drums would be overpacked in new drums prior to handling, a procedure which would contain any leaking contents. Because the drums are frozen, there is little likelihood that they would leak before being overpacked. 3.3.1.4 Aesthetics This alternative would remove the aesthetic impacts of the waste drums currently stored at McMurdo Station. 3.3.2 Alternative 2 Alternative 2 would retrograde all drums from McMurdo for disposal in the United States. 3.3.2.1 Wastewater disposal No drum contents or drums would be disposed of on site, so any impacts from disposal of wastewater at McMurdo would not occur. Nonhazardous drum contents would be disposed of in the United States at a permitted wastewater treatment plant, following pretreatment to remove any oil. Hazardous contents would be disposed of under the turn-key contract (Sect. 2.3.1) following all U.S. hazardous waste disposal regulations. 3.3.2.2 Logistics requirements This alternative is expected to have greater transportation requirements than would the others. Approximately 800 drums would be overpacked, properly labeled, temporarily stored, loaded in mil van shipping containers, and retrograded on the annual supply vessel. As this number of drums is a small portion of the available retrograde cargo space, this alternative by itself would not result in significant increases in transportation requirements for retrograde. The impacts of transporting equipment to McMurdo via air at the start of the 1991þ92 season for Alternative 1 (Sect. 3.3.1) would also occur under this alternative. However, less laboratory equipment and personnel would be required because less extensive analysis of each drum's contents would be conducted. 3.3.2.3 Hazardous spills Little risk of hazardous material or waste spills would occur under this alternative. Drums would be overpacked while still frozen, prior to further handling. 3.3.2.4 Aesthetics As with Alternative 1, the removal of drums under this alternative would have significant benefits for aesthetics. The large number of drums to be retrograded under this alternative could increase the likelihood of unforseen difficulties in disposing of them, if disposal planning and coordination is inadequate. 3.3.3 Alternative 3 Alternative 3 is the no-action alternative. The drums would remain in place. 3.3.3.1 Wastewater disposal Because the drum contents would not be disposed of, no impacts of such disposal would occur. 3.3.3.2 Logistics requirements The only logistics requirements under this alternative would be for occasional inspections of the drums for leaks and the cleanup of any leaks. The costs, pollutant emissions, and impacts to science support of transporting drum handling and laboratory equipment to McMurdo would not occur. However, should drums leak in the future (e.g., as a result of corrosion and warm weather), there could be a sudden and unplanned diversion of support resources to clean up the leakage. 3.3.3.3 Hazardous spills The potential impacts of leaks and spills are greatest under the no-action alternative. The drums can be expected to remain frozen except during unusual warm weather events. The contents of some of the drums may be corrosive; corrosion rates are slow, however, in cold environments. Over the long term, corrosion must be expected to create holes in drums and contents would leak during warm weather. It is likely that over time the number of leaking drums would grow, with the potential for spills. Spills of human waste would have adverse aesthetic impacts and would pose potential health hazards. Impacts to the marine environment of runoff carrying such wastes from the drum storage area can be assumed to be minor compared to the station's discharge of wastewater. Should any of the drums contain flammable or toxic materials (e.g., fuel, used oil, or laboratory chemicals), additional hazards to human health and marine life would occur. Routine inspections of the drum storage area could help identify leaks, which could then be cleaned up. However, given the cold climate, the large number of drums, and the rough, porous nature of the surface of the storage area, undetected leaks can be expected. 3.3.3.4 Aesthetics Under the no-action alternative the adverse aesthetic impacts of the drum storage area would continue. 3.4 RECOMMENDED ALTERNATIVE AND RELEVANCE OF IMPACTS 3.4.1 Recommended Alternative Implementation of Alternative 1 would contribute incremental impacts to marine water quality from an additional wastewater load at McMurdo, although these impacts would be minor compared to the existing wastewater discharge. Alternatives 1 and 2 would have substantial logistics requirements and would result in pollutant emissions and impacts to science support. Alternative 2 may require the shipment of more drums to the United States, but transport via the resupply ship would have little impact on logistics support but would result in additional costs. Alternatives 1 and 2 would eliminate the potential for spills and releases of human waste and hazardous wastes from the drums. The no-action alternative would result in long-term management problems with leakage, and could result in human health and environmental impacts. For the above reasons, Alternative 2 is recommended. This alternative would avoid local impacts of wastewater disposal, with minor additional logistics requirements compared to Alternative 1. The no-action alternative would result in unacceptable risks of leakage, and potential human health and environmental impacts. 3.4.2 Relevance of Impacts As discussed in Sect. 2.4, the additional air transportation requirements for this remedial action are small when compared to total USAP operations. The proposed alternative would have benefits to human health, the terrestrial and marine environment, and aesthetics which outweigh the logistics impacts. In addition, implementation of the proposed alternative would help USAP to continue meet its environmental compliance objectives. 4. COMPLETION OF THE WASTEWATER OUTFALL 4.1 PURPOSE OF THE PROPOSED ACTION The purpose of this proposed waste management action is to provide an extended and submerged wastewater outfall that: reduces the impacts of McMurdo Station's sanitary wastewater effluent, has acceptable environmental impacts associated with its construction, and has an acceptable cost. Environmental impacts of the wastewater effluent include: increased concentrations of oxygen-consuming organic matter [i.e., biochemical oxygen demand (BOD)], increased concentrations of bacterioplankton- and phytoplankton-fertilizing nutrients, increased concentrations of potentially hazardous or toxic substances, and deposition of sewage solids on the bottom of McMurdo Station's nearshore marine environment. The impacts of constructing and maintaining the outfall result mainly from the placement of fill materials (locally obtained rock and imported concrete) on the bottom of McMurdo Station's nearshore marine environment. Another objective of the extended and submerged outfall is to reduce the potential for wastewater to affect the potable water production facility's sea water intake located approximately 0.5 km (about 0.3 mi) south (upcurrent) of the sewage outfall jetty. The wastewater system and its environmental effects are discussed in detail in the Supplemental Environmental Impact Statement for the USAP (NSF 1991a). Wastewater at McMurdo is collected in a heated sanitary wastewater system. Over the history of the station, wastewater has been discharged to McMurdo Sound (including Winter Quarters Bay) at a number of locations. These discharges were all made above the water surface, with the wastewater passing through a hole melted in the sea ice. Since the 1989þ90 austral season, all wastewater is discharged through a single above-surface outfall at the new wastewater outfall jetty. The wastewater is currently macerated and combined with waste brine from the desalinators prior to discharge. The ratio of brine (heated and slightly concentrated sea water) to wastewater flow is about 5.3 to 1. An outfall designed to release water 15 m (50 ft) below the ocean surface was proposed in 1989 (NSF 1989; Sect. 5.2.1.3.2 in NSF 1991a). However, the outfall has, to date, only been extended to a depth of approximately 5 m (16 ft) below low tide elevation (Fig. 3) because icebergs are expected to destroy the outfall if it is extended further offshore. Shortly after its completion at the end of the 1990þ91 season, this outfall was destroyed by unusually high wave action during the period when sea ice over McMurdo Sound was not present. McMurdo Station's wastewater was sampled six times during the 1990þ91 season and laboratory analyses were conducted in New Zealand. These analyses indicate that the effluent, prior to dilution, is a typical strong, raw wastewater. Concentrations of BOD, a measure of how much the effluent depletes dissolved oxygen, range from 300 to 650 mg/L, and concentrations of total suspended solids (TSS) range from 75 to 175 mg/L. Concentrations of nutrients include a range of 20 to 100 mg/L for total nitrogen and 3 to 10 mg/L for total phosphorus. The only unusual characteristic of the wastewater is the high concentrations of some metals (200 to 1500 æg/L of copper, and 50 to 600 æg/L of lead). Copper is of most concern because effluent concentrations are more than 100 times greater than the U.S. Environmental Protection Agency saltwater acute criterion of 2.9 æg/L (USEPA 1985). As these metals are components of plumbing and the water supply is quite corrosive, it is assumed that these metals dissolve from the plumbing system. No measurable concentrations of organic solvents or heavy metals not associated with plumbing were found, indicating that USAP's hazardous waste management practices successfully prevent disposal of such chemicals to the wastewater. 4.2 AFFECTED ENVIRONMENT The marine environment at McMurdo Station was described in the SEIS (NSF 1991a). Additional information on the local environment at the outfall site is provided here. This information is based on observations made by NSF-sponsored researchers studying the marine environment at McMurdo (personal communication, J. S. Oliver and J. M. Oakden, Moss Landing Marine Lab; and J. P. Barry, Scripps Institution of Oceanography; with S. F. Railsback, Oak Ridge National Laboratory, July 26, 1991). 4.2.1 Benthic Zones From the shoreline out to a depth of approximately 6 m (20 ft) the bottom slopes gently. This shallow zone is severely disturbed by anchor ice that attaches to benthic organisms and may pulls them off the substrate. Fig. 3 Between depths of 6 and 10 m (20 to 30 ft), the bottom slopes steeply, and there is more infauna (animals living in the surface sediments) and epifauna (such animals as sponges that live attached to the bottom). The loose sediments, in combination with a steep slope, prevent development of dense benthic communities. At depths greater than approximately 10 m (30 ft) the bottom again slopes gradually and bottom sediments are soft and comparatively undisturbed by anchor ice. Dense benthic communities begin at depths of approximately 20 m (60 ft) and at depths of greater than approximately 25 m (80 ft) the bottom is made up largely of sponge spicules. The zone at depths greater than 10 m (30 ft) should have a rich benthic community at the outfall site, but this area appears to be affected by contamination that is locally concentrated within Winter Quarters Bay (Lenihan et al. 1990). There is a steep gradient of increasing diversity and density in benthic communities going from Winter Quarters Bay, past the outfall site, and south towards Cape Armitage. None of the communities at the outfall site or immediately offshore are biologically exceptional or unique, except that shallow soft bottom communities near McMurdo are apparently not common and are of special research interest. 4.2.2 Currents The currents at McMurdo Station vary greatly over distance and time. The general current patterns have been studied and are believed to include the following. Immediately offshore of the outfall jetty the net current runs northward and deflects offshore at the underwater sill that encloses Winter Quarters Bay. This current is slow, with a mean speed (including tidal oscillations) estimated by Raytheon (1983) to be 5 cm/sec and by J. P. Barry to be approximately 10 cm/sec (0.3 ft/sec). The net speed (averaged over the daily tide cycle) is estimated by Raytheon (1983) to be only 26 m/day. Further offshore, the current flows southward toward Cape Armitage. At least some of the flow near Cape Armitage appears to eddy back northward past McMurdo Station. These currents have not been studied in sufficient detail, however, to confidently predict the fate of effluent (beyond the initial mixing analysis presented below) from alternative outfall locations. 4.2.3 Ice and Wave Considerations Annual sea ice occurs almost year round at McMurdo, breaking out only for a few weeks in some (but not all) years. Sea ice typically reaches thicknesses of up to 2.5 m (8 ft) during the austral summer and breaks up (if it does) in mid-January to February. Anchor ice occurs at depths of up to about 25 m (80 ft), but is ubiquitous on bottom materials only at depths of up to about 6 m (20 ft). At greater depths anchor ice forms mainly on protruding objects such as large rocks or man-made structures. However, structures can be anchored to the bottom to keep them from being lifted by anchor ice's buoyancy. The outfall site is somewhat protected from icebergs by the shape of the Ross Island coastline, and large icebergs are relatively rare. The nearby McMurdo Ice Shelf produces many icebergs, however, and some do follow the shore through the outfall area when not locked in annual sea ice. In general, the shallow zone [less than 6-m (20-ft) depth] is more protected from large icebergs, which would hit the bottom in deeper water. However, even small icebergs, when combined with wind and waves, can damage marine structures. The outfall jetty that was completed in the 1990þ91 season was destroyed by waves and wave-driven ice. The annual ice went out from almost all of McMurdo Sound, resulting in unusually high waves. The rock jetty was almost entirely eroded away by the waves. 4.3 ALTERNATIVE ACTIONS The alternative outfall designs cover a range of tradeoffs between: the greater dispersion provided by increased depth, and the increase in the environmental impacts and costs of constructing and maintaining the outfall that occur with increased depth. 4.3.1 Alternative 1 (Discharge at 15 m) This alternative is based on the original outfall design (Fig. 3) described in the 1989 environmental assessment (NSF 1989) and the SEIS (Sect. 5.2.1.3.2 and Appendix F in NSF 1991a). A discharge pipe would be extended offshore until it reached a depth of about 15 m (50 ft). Through the shallow zone (where the discharge pipe would be subject to wave and ice damage), it would be enclosed within a larger culvert and armored with stone or concrete mats for protection. At greater depths the pipe would not be armored but designed to allow rapid replacement should it be damaged by icebergs. The original outfall design (NSF 1989) called for the discharge pipe to be armored with a jetty all the way to the final depth. Experience with the seawater intake jetty at McMurdo shows that big jetties suffer ice damage and have adverse impacts. This alternative would avoid construction of a large jetty, but as a result, the pipe would be subject to occasional damage by icebergs. There is inadequate bathymetric information to estimate the length of pipe needed. Under Alternative 1, additional studies of currents and wastewater effects would be conducted to determine whether it would be advantageous to extend the outfall even deeper. If the studies indicated an extension was appropriate, the design would be modified as needed. This alternative differs from the design described in previous documents because a smaller diameter pipe and outlet would be used. The smaller outlet would provide greater outlet velocities and, consequently, improved initial mixing of the wastewater with the ocean water. A pipe diameter of 10 cm (4 in.) is considered in this document; ASA estimates that smaller diameters would require too much pressure (head) to force the water out. However, if brine is not mixed with the wastewater a smaller pipe diameter may be feasible and would be beneficial. This alternative is expected to provide the best mixing of wastewater with ambient sea water because the outfall would be deepest (initial mixing here is a function of depth as the wastewater is relatively warm and is, therefore, buoyant). The design would require a large volume of fill material (rock and possibly concrete mats) to anchor the outfall discharge pipe to the bottom and to protect it from ice and waves in the shallow zone. 4.3.2 Alternative 2 (Discharge at 5 m) Consideration of this alternative is based on the outfall as it was actually completed in 1991. The outfall was extended offshore until it reached the edge of the shallow zone, before the steep downward slope. At this point it was about 5 m (16 ft) deep below low tide elevation. A pipe diameter of 10 cm (4 in.) is also considered for this alternative. This alternative would require extensive filling and armoring to prevent damage from ice and waves. When completed in 1991, the outfall structure covered approximately 100 m2 (10,000 ft2) of submerged area. Much of this fill was removed by high wave action when the sea ice broke out in February 1991. Concrete mats and gabions (wire baskets filled with stone) have been shipped to McMurdo to augment the rock fill and provide additional protection to the outfall. 4.3.3 Alternative 3 (No Action: Surface Discharge) The no-action alternative would continue the surface discharge that has been in place at the outfall jetty since the 1989þ90 season. All sewage from the station would continue to be discharged at one point, following maceration and dilution with desalinator brine. The discharge melts a hole in the ice surface and eventually mixes downwards into the ambient sea water at the edge of the sound. At the location where the surface discharge enters McMurdo Sound, the depth is about 3 m (10 ft). 4.4 IMPACT ASSESSMENT The environmental impacts of most concern are the effects on ambient water quality, which depend on the dilution provided by each alternative, and the effects of construction. The ability of the wastewater to melt holes in the sea ice where personnel may walk or drive vehicles is a potential safety consideration. Earlier analysis of one of the alternative outfall designs (Appendix F in NSF 1991a) indicated that mixing the sewage with the waste brine from the desalinators provided little environmental benefit. Alternatives 1 and 2 are considered, therefore, both with and without diluting the sewage with brine. Analysis of wastewater impacts to the marine environment based on available data is presented in the SEIS (NSF 1991a). Analysis presented here is provided for comparison of the alternative outfall designs. 4.4.1 Alternative 1 Alternative 1 would include a section of armored pipe extending from the shoreline out to the maximum depth [6 to 10 m (20 to 30 ft)] where wave and sea ice damage is expected. From there an anchored but unarmored pipe would extend to a depth of about 15 m (50 ft). 4.4.1.1 Construction impacts Construction of the outfall would have impacts from collection of the fill material needed to armor the pipe, and from the disturbance of benthic communities. The shallow pipe section would need to be armored with rock and concrete mats. The concrete mats have been shipped previously to McMurdo on the annual supply ship. Gabions have also been shipped to McMurdo. The gabions would be filled with locally-obtained rock and used to protect the pipe. Obtaining fill material at McMurdo usually requires scraping successively thin layers off the surface of frozen, porous volcanic rock. Because few, if any, terrestrial organisms live on or within this rock, minimal impacts to terrestrial biology would result. Collection of fill, however, causes aesthetic impacts (i.e., bulldozer tracks and unnatural landforms) and can alter the balance of snow accumulation and melting. Use of the concrete mats would not have such impacts. Materials placed in depths up to approximately 6 m (20 ft) would have little effect on marine biology because this zone is heavily disturbed by anchor ice and contains very few benthic organisms. Construction disturbance of the steeper 6 to 10 m (20 to 30 ft) deep zone would have more impacts because this zone contains more infaunal and epifaunal organisms. This zone has apparently been affected by contamination from Winter Quarters Bay and is not considered a natural community. Although construction impacts are expected to be local and would further affect small areas of this already disturbed area, no cumulative impacts to the larger area that is affected by Winter Quarters Bay would be anticipated. Alternative 1 would include a pipe extended out to a depth of about 15 m (50 ft). In depths where damage from waves and sea ice is not expected, the discharge pipe would be anchored, but not armored. Therefore, the disturbance to deeper, more dense benthic communities occurring there would be minor. Disturbance would occur mostly at locations where the pipe is anchored to the bottom (e.g., by placing concrete mats over the pipe at a few places). Should this pipe be destroyed by an iceberg, construction divers would replace it with a new one and retrieve the old pipe, if possible. The densest benthic communities are at depths of greater than 20 m (60 ft). Construction of this alternative would not disturb these communities. However, if additional studies of currents and effluent effects indicate that sufficient benefits would result from further extending the outfall, such an extension could be made. 4.4.1.2 Water quality impacts As wastewater at McMurdo Station is macerated only, it contains relatively high concentrations of settleable solid particles. These would settle out onto the ocean floor in the immediate vicinity of the outfall. The expected velocity of water leaving the outfall would be as high as 3 m/sec (10 ft/sec) [with brine dilution, or 0.5 m/sec (1.6 ft/sec) without brine]. Solids are expected, therefore, to settle out over an area several tens of meters across. These solids have high concentrations of organic matter and could heavily fertilize the benthic area they enter. Higher than natural densities of opportunistic, tolerant species, and lower than natural densities of species intolerant of disturbance would occur in the vicinity of the outfall. Fertilization of deep benthic communities, as would occur locally under this alternative, has been predicted to alter the relative species abundances of sponges and the starfishes that prey on them (Dayton 1972). The liquid effluent would rise from the outfall in a buoyant plume. The plume is buoyant since the heated effluent, even when combined with desalinator brine, is less dense than the cold ambient seawater. This plume would rise and disperse in the ambient water until it reaches the underside of the sea ice. At this point it would spread out underneath this ice, gradually cooling and continuing to mix with ambient water. Heat transfer calculations indicate that the plume is capable of weakening or even melting through the sea ice. The dispersion of the effluent plume is predicted using a computer model developed by the U.S. Environmental Protection Agency for this purpose. The methods used for modeling dispersion here are the same as those presented in Appendix F in NSF 1991a, with some changes in input. The following scenario was used for the comparison among alternatives: (1) Effluent flow rateþ0.022 m3/sec or 0.0035 m3/sec with no brine dilution (2) Outlet pipe diameterþ10 cm Effluent densityþ1018 kg/m3 or 997 kg/m3 with no brine dilution (3) Ambient water depthþ15 m (4) Discharge angleþ þ10ø (5) Ambient current speedþ0.05 m/sec (6) Ambient seawater densityþ1028 kg/m3 (7) Distance from shoreline (estimated)þ100 m (8) Height of outfall above bottomþ0.5 m The dispersion is measured by the dilution ratio, which is the ratio of the concentration of a wastewater constituent in the effluent prior to dispersion to its concentration following dispersion. For example, a dilution ratio of 10:1 means that one part of wastewater has been mixed with 9 parts of ambient seawater and the concentration is one tenth of the original concentration. The dilution ratios reported here are those occurring just before the plume reaches the underside of the sea ice. Predictions of dispersion beyond this point are judged to be unreliable. For the Alternative 1 scenario, including dilution of the effluent with the desalinator brine, a dilution ratio of 60:1 is predicted. A constituent with a concentration of 100 units in the wastewater would have a concentration of approximately 16 units (following dilution with brine) at the point of discharge and a concentration of approximately 0.26 units at the point where the plume approaches the underside of the sea ice. The combination of dilution and dispersion provides an overall dilution ratio of 380:1. The plume is predicted to be fairly narrow, less than 4 m (13 ft) across, and to travel 8 (26 ft) m down current and 13 m (43 ft) offshore from the point of discharge to its arrival at the ice surface. Simulation of this discharge scenario without brine dilution predicts a dilution ratio of 340:1. A wastewater constituent with a concentration of 100 units prior to discharge would have a concentration of 0.29 units at the point where the plume approaches the ice. The plume in this case is predicted to be 5 m (16 ft) across and to travel 9 m (30 ft) downstream and 3 m (10 ft) offshore after discharge. If brine dilution is not used, a smaller pipe may be feasible and would further improve dispersion. The effluent from the deep outfall proposed under this alternative would probably be entrained in the net northward current that travels along the front of McMurdo Station and then offshore from Winter Quarters Bay. There is inadequate information on the currents, however, to make this prediction with confidence. Although the direction and speed of this current are not well understood, it appears that eventually it could carry the highly dispersed effluent in an eddy to Cape Armitage and back northward past the drinking water intake. Following such a journey in this slow current the effluent almost certainly would be diluted to negligible concentrations. 4.4.1.3 Safety Heat transport calculations indicate that a discharge submerged 15 m (50 ft) could melt the underside of the sea ice. (Melting would be much less rapid, however, if desalinator brine is not mixed with the wastewater effluent.) The depth of the discharge means that weakened ice could be expected over an area several tens of meters across, a risk to personnel using the ice. Researchers report that the ice near the outfall is traveled commonly. This safety risk could be mitigated by not discharging desalinator brine with the wastewater, by monitoring ice thicknesses, and by marking weakened areas to be off limits to all personnel. 4.4.2 Alternative 2 Alternative 2 would include a section of armored pipe extending from the shoreline out to the maximum depth of about 5 m (16 ft) where protection from iceberg damage can be expected. At this point the wastewater would be discharged. 4.4.2.1 Construction impacts Impacts of constructing the Alternative 2 outfall would be essentially the same as those for Alternative 1. Under Alternative 2 the effects of installing an unarmored pipe to greater depths would not occur. The construction impacts would be limited to: terrestrial impacts of obtaining fill material (NSF 1990a, 1990b), and disturbance of the shallow benthic zone already regularly disturbed by anchor ice. 4.4.2.2 Water quality impacts As under Alternative 1, organic solid particles would settle out over an area several tens of meters across near the outfall. Under Alternative 2, the solids would be deposited in the shallow zone that is regularly disturbed by anchor ice, and, perhaps, on the steep slope leading to depths greater than 10 m (33 ft). Some soft-bottom-community organisms will be destroyed or displaced by construction. Opportunistic species that colonize following anchor ice disturbance are the most likely to inhabit the area affected by wastewater solids. Since no diverse epifaunal benthic communities would be near the outfall, and the infaunal organisms may be somewhat less diverse than in shallower water, the local impacts of deposition of solids would be less than under Alternative 1. The methods used for Alternative 1 to predict dispersion of the buoyant effluent plume were also used to predict dispersion under Alternative 2. The changes in input for simulation of this alternative are that the depth of the ambient water is 5 m (16 ft) and the distance from shoreline is estimated to be 20 m (65 ft). For the Alternative 2 scenario, simulating dilution of the effluent with desalinator brine, a dilution ratio of 19:1 is predicted. A constituent with a concentration of 100 units in the wastewater would have a concentration of approximately 16 units (following dilution with brine) at the point of discharge and a concentration of approximately 0.84 units at the point where the plume approaches the underside of the sea ice. The combination of dilution and dispersion provides an overall dilution ratio of 120:1. The plume is predicted to be less than 2 m (6 ft) across, and to arrive at the underside of the ice 3 m (10 ft) down current and 3 m offshore from the point of discharge. Under Alternative 2, simulating the discharge with no brine dilution, a dilution ratio of 30:1 is predicted. A wastewater constituent with a concentration of 100 units prior to discharge would have a concentration of 3.3 units at the point where the plume approaches the ice. The plume in this case is predicted to be 1 m (3 ft) across and to travel 2 m (6 ft) downstream and 2 m offshore after discharge. Under this alternative, the effluent would be entrained in the northward current along the shore, with the same consequences discussed in Sect. 4.4.1 for Alternative 1. 4.4.2.3 Safety Heat transport calculations indicate that the discharge under this alternative is likely to melt a hole through the sea ice. Such melting could be a safety risk to personnel on the ice near the outfall. However, the shallow depth of the discharge and the slow currents would limit melting to a relatively small area that could be marked as off limits to mitigate any risk. 4.4.3 Alternative 3 The no-action alternative would continue the existing surface discharge of wastewater. 4.4.3.1 Construction impacts This alternative would involve no further construction or construction impacts. 4.4.3.2 Water quality impacts The surface discharge melts a large hole in the sea ice, several meters across. No field studies of the immediate fate of the surface discharge have been done. The following assumptions of what happens to the effluent after discharge are based on observations by divers and on the known characteristics of the effluent and environment. The effluent is assumed to be contained initially by the sea ice on the sides of the hole and to float on top of the denser ambient seawater. While so trapped, the effluent gives up heat to the air and cools. Cooled effluent moves away from the hole underneath the sea ice and has been observed to occur in high concentrations in the tidal cracks along the shoreline. The hole where the effluent is initially trapped appears to act as a settling basin. Solids have been observed by divers to be settling to the ocean floor beneath this hole. It can be assumed that most of the organic settleable solids in the wastewater are deposited within a few tens of meters of the outfall. However, high concentrations of fecal coliform bacteria have been found on the bottom at isolated locations much further from the outfall, indicating that solids can travel some distance before settling out. There is little chance for dilution of the effluent before it cools and spreads out under the ice and along cracks, with the exception of the dilution provided by desalinator brine. It must be assumed that a wastewater constituent with a concentration of 100 units in the sewage is diluted with brine to a concentration of approximately 16 units, and then migrates under the ice or along cracks at or near this concentration. The surface discharge is immediately adjacent to the shoreline, so the effluent can be assumed to follow the northward current, with consequences as described in Sect. 4.4.1 for Alternative 1. However, transport along tidal cracks provides a mechanism for the effluent to travel rapidly along the shore in both directions. The surface outfall allows locally high concentrations in tidal cracks, a phenomenon not expected with alternatives 1 or 2. 4.4.3.3 Safety The hole melted in the sea ice by the surface discharge poses a safety hazard because it is adjacent to the shoreline and relatively accessible. However, the discharge pipe and the melt hole are well defined, and highly visible during daylight. Such measures as fencing off the vicinity of the hole could adequately mitigate this potential hazard. 4.5 RECOMMENDED ALTERNATIVE AND RELEVANCE OF IMPACTS 4.5.1 Recommended Alternative Considering the effects of brine dilution and dispersion under the conditions simulated, Alternative 1 would provide dilution ratios of 340 to 380:1, whether or not desalinator brine is discharged with the wastewater. Alternative 2, with brine dilution, would provide dilution ratio of 120:1. The existing surface discharge provides only the 6.3:1 dilution provided by the desalinator brine. Expected increases in ambient concentrations of important wastewater constituents, under the three alternatives, are shown in Table 3. Table 3. Characteristics of wastewater before and after mixing for 3 alternatives Consti tuent Effluent concen- tration Concentration after mixing, Alternative 1 Concentration after mixing, Alternative 2 Concentration after dilution, Alternative 3 BOD, mg/L 300þ650 .88þ1.9 2.5þ5.5 48þ100 Total Nitrog en, mg/L 20þ100 .06þ.29 .17þ.84 3.2þ16 Total Phosph orus, mg/L 3þ10 .01þ.03 .03þ.08 .48þ1.6 Copper , æg/L 20þ1500 .06þ4.4 .17þ13 3.2þ240 Microbial decay of wastewater organics, measured as BOD, depletes dissolved oxygen (DO) in the receiving water. Since McMurdo Sound has naturally low DO concentrations [typically 7 mg/L before the summer algae bloom (Barry 1988)], further DO depletion is of concern. Theoretically, the DO concentration could be lowered by as much as the BOD concentration, but usually natural re-aeration replaces some of the DO as it is consumed. The ice cover and relatively low currents at McMurdo, however, are expected to make natural re-aeration low. For example, a BOD concentration of 2 mg/L, therefore, may reduce actual DO concentrations by up to 2 mg/L. Under Alternative 3, it is clear that DO depletion, therefore, could be severe and widespread as the high BOD concentrations spread out underneath the sea ice. Under Alternative 2, DO could be depleted by 2 to 5 mg/L under the sea ice, which would cause locally discernable effects on marine organisms but these effects would probably not be widespread. Under Alternative 1, no serious DO depletion would be expected. Comparison of the above predicted nutrient (nitrogen and phosphate) concentrations to ambient values presented in the SEIS (p. 4þ6 in NSF 1991a) shows results similar to those for DO: Alternative 3 would result in nutrient concentrations much higher than ambient, Alternative 2 would result in local nutrient concentrations roughly double ambient, and Alternative 1 would result in minor changes. Copper, the heavy metal of greatest concern, would exceed the EPA acute exposure criteria (2.9 æg/L) constantly under Alternative 3. Exceedances would also occur some of the time under alternatives 1 and 2. However, this problem would be best mitigated by initiating pH control and buffering of potable water (e.g., by employing a limestone contactor) to reduce the corrosiveness of the water supply. Such a contactor has been recommended and approved for procurement. Considering the effects of brine dilution and dispersion under the conditions simulated, Alternative 1 would provide dilution ratios of 340 to 380:1, whether or not desalinator brine is discharged with the wastewater. Alternative 2, with brine dilution, would provide dilution ratio of 120:1. The existing surface discharge provides only the 6.3:1 dilution provided by the desalinator brine. In the long term, it is believed that under each alternative the effluent would be highly dispersed in the current eddy that appears to flow between Winter Quarters Bay and Cape Armitage. Each of the alternatives would deposit solids on the bottom. Under Alternative 1, these solids would be deposited closer to the rich benthic communities that occur in deep water, but the outfall could be placed to avoid direct effects to such communities. Under alternatives 2 and 3, solids would continue to be deposited in areas with little benthic life. Alternatives 1 and 2 would result in construction impacts, including collection of fill material on land and covering of a strip of the ocean floor to anchor and armor the pipe. This disturbance would occur mostly in shallow zones with little benthic life. (Alternative 1 would include small local pipe anchors in deeper water.) Alternative 3 would have no such construction impacts. Reducing the concentration of dissolved and suspended wastewater constituents is the most important objective of the outfall. Alternative 1 provides significantly greater mixing than the others. This alternative, if feasible to implement, has no distinguishably adverse impacts compared to the others. Therefore, this alternative is recommended. 4.5.2 Relevance of Impacts The recommended alternative would reduce wastewater impacts to the water offshore at McMurdo, an important research area. Construction of this outfall and deposition of wastewater solids from it would have only local effects on the benthic environment, and the richest benthic communities could be avoided. This proposed action would have important environmental benefits and no discernably adverse impacts. The impacts of an outfall design very similar to the proposed action have been assessed in two previous documents (NSF 1989, NSF 1991a). If the deep outfall is installed, it is recommended that desalinator brine not be discharged through it. Not discharging the brine would reduce melting of the sea ice above the outfall. Using the smallest possible pipe diameter would provide dispersion equal to or better than with brine dilution. The brine can be used for other purposes such as heating buildings or for flushing toilets. 5. RECOMMENDATIONS The following recommendations are made to USAP decisionmakers, based on the analysis of impacts contained in this EA. 5.1 REMEDIATION OF FORTRESS ROCKS The proposed cleanup of asbestos contamination and surface wastes is needed to remove this risk to health and the environment. The impacts of this cleanup mostly result from the logistics and transportation requirements of providing the needed equipment. These impacts are minor compared to other USAP operations and are offset by the benefits of this action. The overall impacts of this action are positive and not likely to be more than minor or transitory in nature. 5.2 REMOVAL OF LIQUID WASTE DRUMS The accumulation of old drums at McMurdo clearly needs to be removed to prevent potential spills and reduce adverse aesthetic impacts associated with the exiting storage area. The proposed action would remediate this problem and would have few impacts. Transporting all of the drums to the United States for disposal (Alternative 2) offers the benefit of minimizing the work required at McMurdo and would have few negative impacts compared to disposing of some drums at McMurdo (Alternative 1). The overall impacts of this action are positive and not likely to be more than minor or transitory. 5.3 COMPLETION OF THE WASTEWATER OUTFALL The wastewater dispersion analysis shows that local wastewater impacts are clearly minor only if a deep [15 m (50 ft)] outfall is used. A shallower submerged outfall [5 m (16 ft) deep] would result in local, but usually minor, impacts to water quality. Either of these outfall designs is clearly preferable to the existing surface outfall, so neither Alternative 1 nor Alternative 2 would have overall impacts that are more than minor or transitory in nature. A deep outfall would perform best with as small an outlet pipe diameter as possible. Dilution with brine appears to offer little benefit with a deep outfall, although it is important when a surface or shallowly submerged outfall is used. The decision of whether to install a deep outfall depends in part on engineering considerations. Occasional (but not necessarily frequent) iceberg damage must be expected, and experience has shown that construction of massive jetties does not guarantee that a submerged structure will avoid damage. The best way to deal with iceberg damage may be to design an outfall that can be repaired easily if damaged. It is recommended that a submerged outfall be installed. The outfall should be designed to discharge from a depth of at least 15 m (50 ft) if possible. The outfall should be designed to minimize the impacts to benthic communities (where they occur) that result from placement of fill and from sewage solids. Should it be determined that such a deep outfall is infeasible, the outfall should be placed as deeply as possible. The most apparent impact of the existing wastewater discharge is the high metal concentrations in the effluent. The current plans to buffer and control the pH of the drinking water supply should remediate this problem; such plans should be completed expeditiously. 6. REFERENCES Dayton, P. K. 1972. "Toward an understanding of community resilience and the potential effects of enrichments to the benthos at McMurdo Sound, Antarctica. (Pp. 81þ96)." In B. C. Parker (ed.). Proceedings of the Colloquium on Conservation Problems in Antarctica. Virginia Polytechnic Institute & State University, Blacksburg, Virginia (September 10þ12, 1971). Lenihan, H. S., J. S. Oliver, J. M. Oakden, and M. D. Stephenson. 1990. "Intense and localized benthic marine pollution around McMurdo Station, Antarctica." Marine Pollution Bulletin 21(9):422þ30. National Science Foundation (NSF) 1989. Environmental Impact Assessment for Improvement of Sanitary Wastewater Management at McMurdo Station, Antarctica. Division of Polar Programs, Washington, D.C., December 1. National Science Foundation (NSF) 1990a. Environmental Action Memorandum (Blasting for, and Placement of, Fill Rock at McMurdo Station, Antarctica During the 1990-1991 Season). Division of Polar Programs, Washington, D.C., October 2. National Science Foundation (NSF) 1990b. Review of "Environmental Assessment for Collection (and Placement) of Earth Fill Material". Division of Polar Progarms, Washington, D.C., November 17. National Science Foundation (NSF) 1991a. Final Supplemental Environmental Impact Statement for the United States Antarctic Program. Division of Polar Programs, Washington, D.C. National Science Foundation (NSF) 1991b. Environmental Action Memorandum: Installation of Temporary Incinerator at McMurdo Station, Antarctica. Division of Polar Programs, Washington, D.C. (March 19, 1991). National Science Foundation (NSF) 1991c. Supplemental Environmental Analysis: Installation of Temporary Incinerator at McMurdo Station, Antarctica. Division of Polar Programs, Washington, D.C. (June 14, 1991). National Science Foundation (NSF) 1991d. Environmental Impact Assessment: The U.S. Antarctic Program's Management of Food and Selected Domestic Wastes at McMurdo Station, Antarctica. Division of Polar Programs, Washington, D.C. (August 12, 1991). Reed, S. C., and R. S. Sletten. 1989. Waste management practices of the United States Antarctic Program. Special Report 89-3. U.S. Army Corps of Engineers Cold Regions Research and Engineering Laboratory, Hanover, New Hampshire. APPENDIX A SAMPLING AND ANALYSIS METHODS FOR DISPOSAL OF LIQUID WASTE DRUMS Source: Kenneth Z. Crumrine AECOM Technology Corporation [Excerpt From: Draft Sampling and Analysis Plan AECOM Antarctic Environmental Program) Initial Environmental Evaluation Panel for Accelerated Implementation of Waste Management Actions at McMurdo Station, Antarctica The following individuals provided information or guidance in the preparation of this Initial Environmental Evaluation: Sidney Draggan, Panel Chair Environmental Officer Division of Polar Programs Peter E. Wilkniss Division Director Division of Polar Programs Carol A. Roberts Deputy Division Director Division of Polar Programs Whitney Slater Budget and Planning Officer Division of Polar Programs Gary T. Staffo Safety and Health Officer Division of Polar Programs Erick Chiang Manager, Operations Section Division of Polar Programs Robert Haehnle Facilities Engineering Projects ManagerDivision of Polar Programs David Bresnahan Field Projects Manager Division of Polar Programs Deh-i Hsiung Operations Research Analyst Division of Polar Programs Thomas Forhan Head, Antarctic Staff Division of Polar Programs Lawrence Rudolph Deputy General Counsel NSF, Office of the General Counsel Anita Eisenstadt Assistant General Counsel NSF, Office of the General Counsel Miriam Leder Assistant General Counsel NSF, Office of the General Counsel Alan B. Crockett Idaho National Engineering Laboratory Robert T. Reed Oak Ridge National Laboratory Richard B. McLean Oak Ridge National Laboratory Steven F. Railsback Consultant Terry Johnson Antarctic Support Associates Gene Klun Antarctic Support Associates Craig Martin Antarctic Support Associates LT Margaret Kurowski Naval Support Force Antarctica LT Keith Forman Naval Support Force Antarctica MAJ Sonia Gaidelis Naval Support Force Antarctica Kenneth Z. Crumrine AECOM Technology Corporation Art Jung AECOM Technology Corporation