Castle Airport - Pollution

Pollution

Since the mid-1940s, aircraft maintenance, fuel management, and fire training activities on the base have generated wastes that consist primarily of waste fuels, oils, solvents, and cleaners. Base activities also have generated lesser amounts of paints and plating wastes.

The EPA currently has this base listed on their database due to the bulk wastes such as solvents, oils, fuels, and sludges which were disposed in pits at landfills around the base until 1977. Fuel and waste oils were incinerated by the Air Force during fire training exercises. The Air Force ceased disposal of hazardous waste on site in 1977, and the base was officially closed in 1995. During the following cleanup efforts, all hazardous and toxic materials that the Air Force was unwilling or unable to transport offsite were sealed into four onsite landfills.

EPA investigations have been completed at multiple areas of contamination including landfills, discharge areas, chemical disposal areas, fire training areas, fuel spill areas, and polychlorinated biphenyl (PCB) spill areas. Through the fiscal year 2006, $164.27 million was spent on cleanup activities at Castle. The USAF expects to spend an additional $70.98 million through fiscal year 2044. Approximately 6000 people obtain their drinking water from both municipal and private wells located near the site. The principal pollutant at the base, trichloroethylene (TCE), was found in a plume. Merced Irrigation purified the water at the edge of the plume and released the purified water outside the plume. Working their way inward, they managed to clean the contaminated water. The methods used to purify the groundwater included passing the water through carbon filters and then aerating it. The pollutant remaining after purification was packaged in a barrel and removed from the site. In 1991, a Base Realignment and Closure (BRAC) Cleanup Team (BCT) was created to review and offer comments/recommendations on the progress of the cleanup effort at Castle. BCT membership included representatives from the Air Force, federal and state regulatory agencies, and appointed representatives from the governing bodies of surrounding communities. The Castle RAB, or Restoration Advisory Board, which was established in 1994 on behalf of the former Castle Air Force Base, was responsible for reviewing Federal cleanup methods and efforts, and was officially adjourned on January 16, 2007.