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UPDATE - 8/09
A fact sheet on the work and findings of the summer 2009 cleanup efforts is available below.
Description
Aniak is located on the south bank of the Kuskokwim River at the head of Aniak Slough in the Yukon-Kuskokwim Delta with a population of 528, it lies 92 air miles northeast of Bethel and 317 miles west of Anchorage.
The Aniak Middle School building and property was initially developed and used by the Air Force in the 1950s in the military/civilian "White Alice" communication system during the Cold War. By the late 1970s the military facility was obsolete and was turned over to the School District, which renovated the main building and used it for a school from 1981 until 2003. The Alaska Department of Transportation and Public Facilities has owned the property since 1965 and currently leases the site to the Kuskokwim School District and ALASCOM, Inc.
During White Alice operations and renovation of the school by contractors, fluids containing polychlorinated biphenyls (PCBs)
were spilled in and around the generator room and onto the ground outside the building, resulting in soil contamination. Hazardous materials were placed into drums that were moved to various locations on the property, where additional spills reportedly occurred. Most of those drums were ultimately shipped to a disposal facility out of state.
The U.S. Air Force and ADEC conducted PCB cleanup at the site between 1979 and 1983 and attempted to remove all PCB contaminated material and soil containing more than 50 parts per million (ppm) PCB. Approximately 80 tons of PCB-contaminated soil were excavated and shipped to a permitted disposal site, along with numerous drums of other wastes. In 1981 a sealant was applied to the floor of the former generator room, which in later years was used as a wood shop, and a better sealant was added to the floor in 1983.
In 1983 DEC conducted extensive environmental sampling and tested water from the well at the site and from several homes in Aniak. None of the water well samples contained PCBs. That same year, the State Epidemiologist conducted an investigation, interviewing seven workers in the White Alice site, four of whom had also been involved in the building renovation. Blood samples of these workers, highly exposed to PCB oil and other materials at the site, proved to be the range of levels of PCBs considered normal. (See report below)
In 1994, DEC was notified of additional drums and possible contamination at the site. DEC staff inspected the site in 1996 and found about 60 drums in alders between the school and the airport runway. The U.S. Army Corps of Engineers (Corps) tested the ground beneath the drums and documented petroleum contamination. Since the land was used, but no longer owned, by the military the Army Corps of Engineers assumed responsibility for the military's portion of the contamination under "Formerly Used Defense Site Program."
In 1997, the U.S. Environmental Protection Agency (EPA) released a report that showed PCBs remained in soil outside the middle school wood shop, which was the former generator room at the White Alice Site. Subsequent sampling inside the school documented that PCBs had been tracked into the building. With DEC oversight, the Corps’ contractors cleaned the inside of the Middle School and covered PCB-contaminated soil outside the school with a temporary liner and six inches of clean soil. The cover was put in place to ensure that people would not come in direct contact with contaminated soil and to prevent further tracking of PCBs into the school or other areas. DEC mailed several fact sheets to all Aniak post office box holders during 1997-98 to inform the community of the investigation and cleanup efforts. A public meeting was held in Aniak in January 1998 to discuss these issues and answer questions.
A health study in 1998 tested the school's students, faculty and maintenance staff. The data showed that students and faculty involved in the tests did not have any measurable levels of PCB in their blood serum. Serum samples from some of the cleanup workers and maintenance staff contained detectable PCB levels, however, they were found to be within or below commonly observed levels for Americans and were far below any levels that have been shown to have toxic effects. The report concluded that residents have not been exposed to harmful levels of PCBs at the site and that PCBs which had been temporarily covered at the site should be cleaned up to appropriate levels. The results were summarized in a Health Consultation report by the U.S. Agency for Toxic Substances and Disease Registry, issued in 1999. (See report below)
Since 1998, DEC has been working with the potentially responsible parties (PRPs) for PCB contamination at the site including: the federal government, the State (as the landowner), the Kuspuk School District and its contractors that renovated the site, and the Air Force contractors that operated the White Alice site. Negotiations are on-going in an effort to develop a settlement agreement on completing the cleanup and allocating past and future cleanup costs among the parties.
Between 1998 and 2001, DEC hired contractors to better characterize the extent and location of remaining PCB contamination adjacent to the woodshop and clean up a portion of the site. These efforts demonstrated the remaining contamination in that area was subsurface; therefore, there was no current exposure to it. A portion of the PCB contaminated soil outside the woodshop was excavated and approximately 870 tons of PCB contaminated soil were shipped off-site for disposal at a permitted facility. Additional PCB contaminated soil remains beneath the temporary cap (liner and clean soil). (See report below, "PCB Cleanup, Aniak Middle School", S&W, December 2001)
In 2002-03, DEC hired a contractor to complete a feasibility study to evaluate seven different alternatives for completing the cleanup. Excavation and off-site disposal of soil containing more than 1 ppm PCB was recommended as the best overall alternative when considering regulatory compliance, protection of human health and safety, implementability, effectiveness and cost. (See report below, "Feasibility Study for Treating PCB-Impacted Soil, Aniak Middle School," S&W, Jan. 2004)
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| Septic trench dug in Aniak in October 2006 to allow sampling. Trench was backfilled after sampling. |
In 2004, the Alaska Department of Law sent letters to the potentially responsible parties (PRPs) requesting reimbursement of past State costs for responding to the PCB contamination and completion of the cleanup as outlined in the feasibility study report, or the State would conduct the cleanup and seek full cost recovery. The PRPs responded by requesting the State provide time for them to conduct a separate feasibility study, as they did not concur with the existing one. Subsequently, URS Corporation completed a separate feasibility study report under contract to the private PRPs. That report recommends excavation and off-site disposal of soil with PCBs greater than 10 milligrams/kilogram (mg/kg), capping all soil where PCBs remain at concentrations between 1 and 10 mg/kg, and development of institutional controls to ensure the cap is maintained indefinitely.
Between 2004 and now, DEC, the Dept. of Law, and the PRPs have been negotiating through an alternative dispute resolution process in an effort to reach a settlement agreement on the past and future cleanup costs and work. Extensive records reviews and information exchange have been completed, witness lists were created, depositions held, and negotiations are continuing. Questions were raised on PCB contamination in and potentially around the White Alice site septic system.
In October of 2006, DEC's contractor sampled the contents of the former White Alice site septic system, soil around the septic system and soil near a former drum storage area. The results showed concentrations of PCBs, arsenic, chromium and TCE above cleanup levels in the septic system and soil, thus expanding the area of concern that warrants additional cleanup. (See report below, “Septic System and Area F Characterization, Former White Alice Communication System, Aniak, May 2007).
Public Health and Environmental Concerns
Polychlorinated biphenyls (PCBs) are the primary contaminant of concern at the site. A chlorinated solvent (trichloroethylene or TCE) has been found in the former White Alice site septic system and nearby soil and groundwater. Low levels of TCE and petroleum are also present in groundwater in localized areas off the school property adjacent to the runway apron. The school and nearby residential drinking water wells have been sampled previously and found to meet drinking water standards.
PCBs are stable, heat tolerant materials that were added to electrical transformer oils to extend the time that the oil was usable. PCBs were also used in other materials including other electrical equipment, some caulk, paints, sealants and hydraulic fluids. In the late 1970s, manufacture and use of PCBs in new products was banned in the United States in response to concern over possible health effects.
Potential health effects from PCBs are influenced by the concentration of PCB someone is exposed to, how long they are exposed, and how they are exposed (skin contact versus breathing or eating material containing PCB). Other factors that may influence effects are the other chemicals someone is exposed to and their age, sex, diet, family traits, lifestyle, and their overall state of health. See the Agency for Toxic Substances and Disease Registry's fact sheet for more information on the health
effects from exposure to PCBs.
Current Status
In the Spring of 2008, DEC hired a contractor to complete the PCB cleanup work and further characterize the source and extent of TCE contamination. The TCE characterization was being done to determine whether any cleanup actions are necessary to address that contaminant. The PCB cleanup objectives are to remove PCB-contaminated soil to the unrestricted use cleanup level (1.0 mg/kg PCB) and transport the soil and related cleanup wastes to a permitted disposal facility in the Pacific Northwest. The contract included removing and properly disposing an old septic system and resampling floors inside the former WACS / Middle School / Voctech building to determine whether PCBs have been tracked into the building and to evaluate the adequacy of the sealant placed on the woodshop floor in the early 1980s. Work was scheduled to occur when the school was closed for the summer. Contractors for DEC began work in May. See May 9th, 2008, letter below to Aniak residents for details.
Unfortunately, workers this summer found a significantly larger amount of soil contaminated with PCBs behind the Votech building than expected. The soil is near the old septic system and a concrete truck loading rack for the fuel system that was installed in 2005. The septic tank contained elevated levels of PCB and TCE. Fieldwork continued into mid September, when work was stopped due to funding and barge access limitations. A fence will be installed around the behind the building where soil was excavated this summer and additional excavation is planned next summer. An area on the east side of the Votech building has PCB contaminated soil remaining in place. This soil is covered with a fabric liner and clean gravel. DEC is asking for and will appreciate community cooperation in continuing to stay out of these areas until the fieldwork is done.
Floors inside the Votech building were sampled for PCBs. In the wood shop an area where the floor sealant was damaged, PCBs were found above applicable federal standards. Other areas in the wood shop where the sealant was in good shape tested clean as did floors in other areas inside the building. The Kuspuk School District plans to reseal and paint the woodshop floor before holding classes in that room.
PBC contaminated soil will remain inside a fenced area on the West side of the Votech building and underneath the fabric liner and gravel cover on the east side of the building; these areas will need to be cleaned up under a future contract. The Votech school building and surrounding property can be safely used as long as people stay out of the fenced area and do not dig through or expose soil beneath the temporary liner on the East side of the building.
DEC is continuing cost recovery negotiations with the various potentially responsible parties.
More Information
Reports and Communications available:
- Fact sheet, August 2009, with update on contamination and cleanup efforts. (PDF 888K)
- Letter to Aniak residents, June, 2009, from DEC, updating residents on progress. (PDF 176K)
- Letter to Aniak residents, August 18, 2008, from DEC, updating residents on progress. (PDF 741K)
- Letter to Aniak residents, May 9, 2008, from DEC, describing the plans for the summer of 2008. (PDF 821K)
- Septic System and Area F Characterization, Former White Alice Communication System, Aniak, May 2007, without Tables and Appendices (PDF 1.9MB)
- Tables, Figures and Appendices (PDF 16 MB),
- Appendix B only, with site photos (PDF 1.8M)
- Feasibility Study for Treating PCB-Impacted Soil, Aniak Middle School, Shannon and Wilson, January 2004 (PDF 1.5MB )
- PCB Cleanup, Aniak Middle School, Shannon and Wilson, December 2001, (PDF 1MB )
- 1999 Health Consultation Aniak Middle School Report, by the Alaska Department of Health and Social Services under cooperative agreement with the U.S. Agency for Toxic Substances and Disease Registry (PDF 344K)
- 1983 Memorandum of the State Epidemiologist's Investigation of PCBs in Aniak, December 19, 1983, by John Middaugh, M.D. (PDF 460K)
DEC fact sheets
- Cleanup process for contaminated sites (PDF 304K)
- How DEC Makes Cleanup Decisions (PDF 20K)
- Introduction to Groundwater (PDF 412K)
- Understanding Contaminant Concentrations (PDF 164K)
- Department of Defense Cleanups (PDF 59K)
- Environmental Laws (PDF 39K)
- Cleanup Methods (PDF 171K)
Maps
- See also maps of the site area and sections named for reference, in Shannon and Wilson's 2004 Feasibility Study (PDF file, 173 K)
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