McALLISTER POINT LANDFILL |
Fact Sheet Update (May 2007 DRAFT) BACKGROUND The site was used as a landfill from the mid-1950s to the mid-1970s to dispose of a variety of wastes, reportedly including domestic refuse, spent acids, paints, solvents, waste oils, PCB-contaminated transformer oils, and construction debris. From 1955 to 1970, nearly all disposed waste was burned in an on-site incinerator. Following landfill closure in the mid-1970s, a 3-foot thick soil cap was installed. STUDIES The Navy conducted Phase I and II RI field work in 1993 and 1994. The Remedial Investigation report revealed that fill thickness ranges from 3 to 8 feet in the north, to 25 to 27 feet along the western portion of the landfill. Landfill material is composed of municipal and industrial waste (plastic, wood, paper, cloth, garbage, and construction debris) with a layer of ash (from the on-site incinerator) present in the north-central portion of the site. Risk assessments determined that there were unacceptable risks to humans ingesting contaminated shellfish (mussels and clams) that were present at the site and a high potential for risk to ecological receptors at several near shore areas. CLEAN-UP In 1995 and 1996, the Navy constructed a RCRA C-type cap for the landfill to reduce contaminant leaching and transport.
A final Record of Decision (ROD) was signed that described the decision to dredge the most contaminated sediment, and conduct long term monitoring at the offshore area to the south and west of the landfill. The dredging effort was completed in December 2001.
In addition, the Navy conducted a habitat mitigation effort in the offshore area of the site to promote eelgrass growth in this area between 2001 and 2004. CONTINUED ACTIVITIES Periodic monitoring of sediment, groundwater, and landfill gas emissions, as well as five year reviews of the remedy will continue in accordance with the ROD to assure the remedy is protective.