NPL Site Narrative for Williams Air Force Base
WILLIAMS AIR FORCE BASE
Federal Register Notice: November 21, 1989
Conditions at proposal (July 14, 1989): Williams Air Force Base (WAFB) covers 4,127 acres approximately 30 miles southeast of Phoenix, Arizona, in Maricopa County, near Chandler. The base is surrounded by irrigated farmland or desert. Since the base was constructed in 1941, it has served as a training facility, primarily pilot training. Industrial activities at WAFB have included heavy maintenance of aircraft and ground equipment in support of pilot training.
WAFB is participating in the Installation Restoration Program (IRP), established in 1978. Under this program, the Department of Defense seeks to identify, investigate, and clean up contamination from hazardous materials. As part of IRP, the Air Force has identified a number of potentially contaminated areas, including Fire Protection Training Area No. 2, which covers approximately 8.5 acres near the southern boundary of the base. Prior to 1948, the area was used as a parking apron. From 1948 until the late 1960s, it was an unlined pit where large quantities of the flammable liquid waste generated at WAFB were burned as part of fire training. Any flammable materials remaining infiltrated the soil or evaporated. These materials included waste fuels, oils, lubricants, cleaning solvents, and some paint stripper. Starting in 1983, a concrete liner was installed under the burn pits; however, overflow is still allowed to seep into the ground. In September 1986, an Air Force contractor found lead in soil, and in March 1987 found lead in monitoring wells on the base.
The Southwest Drainage System (SWDS) has operated since the base was constructed in 1941. It received plating shop rinse water containing chromium, cadmium, and copper; aircraft washing wastes consisting of methyl ethyl ketone, toluene, polyurethane, paint thinners, and sludges; fuel; lubricants; hydraulic fluid; and spills from flight line and maintenance operations. SWDS soil samples taken in October 1984 contained lead, chromium, and cadmium. SWDS drains into a storm water retention pond in the southwest corner of the base. In 1988, the Air Force installed a concrete lining in part of SWDS. WAFB housing is within 100 feet of SWDS.
A 34-acre landfill in the southwest corner of the base operated during 1941-76, accepting primarily trash and garbage. However, unknown quantities of hazardous waste were dumped along with the household wastes. In April 1987, lead and cadmium were detected in monitoring wells, including one between the landfill and SWDS and adjacent to the pond that received SWDS wastes.
WAFB has four wells that supply drinking water to an estimated 3,400 employees. One of the wells is 1,500 feet from the contaminated well at the landfill.
The Air Force has completed an initial assessment of the base and is developing a workplan for a remedial investigation/feasibility study (RI/FS) to determine the type and extent of contamination and identify alternatives for remedial action. Field investigations are underway.
Status (November 21, 1989): The Air Force is continuing to develop the RI/FS workplan and has installed a few additional monitoring wells.
For more information about the hazardous substances identified in this narrative summary, including general information regarding the effects of exposure to these substances on human health, please see the Agency for Toxic Substances and Disease Registry (ATSDR) ToxFAQs. ATSDR ToxFAQs can be found on the Internet at ATSDR - ToxFAQs (http://www.atsdr.cdc.gov/toxfaqs/index.asp) or by telephone at 1-888-42-ATSDR or 1-888-422-8737.