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IOSCO COUNTY
OSCODA
Congressional District # 01
WURTSMITH AIR FORCE BASE
EPA ID# MI5570024278Last Updated: July, 2009
Site Description
Wurtsmith Air Force Base (Wurtsmith) is a 5,223 acre site, located on the northeastern part of Michigan's lower peninsula about two miles west of Lake Huron. To the north and northeast of the site is Van Etten Lake, to the southwest is Allen Lake, and to the southeast and east is the village of Oscoda. Of the 5,223 acres, 1,943 acres are owned by the U.S. Air Force. The rest of the facility consists of 2,466 acres that are leased primarily from the state and 814 acres that are registered as easement tracts.Wurtsmith has operated since 1923 under several different names, beginning as a subsidiary of Selfridge Field, called Camp Skeel. Until World War II, Camp Skeel was used for gunnery practice, winter maneuvers, and aircraft landings. According to The Emergency War Order, the primary mission of the base was to maintain full readiness to conduct strategic bombing operations worldwide. Support activities at the base included aircraft and vehicle maintenance, bombardment crew and unit training, and air refueling support. The base was renamed Oscoda Army Air Field when the Continental Air Command began using it as a transient aircraft stopover. In 1953, the base was renamed back to Wurtsmith Air Force Base when it came under the command of the U.S. Air Force Strategic Air Command.
In November 1977 while collecting groundwater samples, the Air Force detected trichloroethylene (TCE) in three of the seven drinking water wells on the base. Additional samples collected in 1979 and 1980 also detected TCE. In 1985 during the early stages of base closure, the Installation Restoration Program Phase I records search for Wurtsmith identified 29 sources of concern including the Weapons Storage Area, two former 6,000-gallon tank trailers, the Northern Landfill Area, the Building 43 Area, and the Building 5008 Area. During the 1950s and early 1960s, the Air Force used the Weapons Storage Area as a jet fighter maintenance area, possibly using TCE for degreasing and deicing the jets. The U.S. Geologic Survey (USGS) identified a TCE-contaminated groundwater plume that appeared to be emanating from this area. In 1971, two 6,000-gallon tank trailers were buried in the center of the Northern Landfill Area to create a central depository for waste solvents. The tanks were removed in 1977. The Northern Landfill Area served as a disposal pit from 1960 to 1979 into which the Air Force disposed of domestic and industrial wastes, including solvents, metals, and paints. In 1987, the USGS sampled monitoring wells downgradient of the Northern Landfill area and identified TCE, 1,1-dichloroethane, 1,1,1- trichloroethane, and vinyl chloride. The Air Force used a 500-gallon underground storage tank in the Building 43 Area from 1962 to 1977 to store waste TCE, which it used as a degreaser for the maintenance of fire control equipment in the Building 5008 Area. After removing the tank, a leak was discovered near the fill pipe on the top of the tank. In addition, the Air Force apparently dumped solvents, including TCE, near buildings in the Building 5008 Area for weed control. Pumping drinking water wells in this area caused the contaminants to be drawn toward these wells, resulting in the contamination of additional drinking water wells with TCE. The Air Force officially closed the base in 1993.
Site Responsibility
The site is being addressed through federal actions. The Air Force has the lead responsibility at the site.Threats and Contaminants
The Air Force detected TCE in the drinking water and monitoring wells at the Building 43 Area and at the Building 5008 Area. The USGS identified a TCE-contaminated groundwater plume at the Weapons Storage Area. While sampling monitoring wells downgradient of the Northern Landfill Area where two 6,000 gallon tank trailers were buried, the United States Geological Survey (USGS) also detected the volatile organic compounds TCE, 1,1-dichloroethane, 1,1,1-trichloroethane, and vinyl chloride. Since the soil at the site is primarily sand, any spills or leaks at the surface will move rapidly to the groundwater. Therefore, contaminated soil has not been frequently encountered at the site.A Consolidated Remedial Action Plan (C-RAP), which addresses the disposition of all areas of known or potential contamination, has been reviewed by the United States Environmental Protection Agency (U.S. EPA) and the Michigan Department of Environmental Quality (MDEQ). The C-RAP provides a summary of 88 sites at Wurtsmith. They include 29 remedial action sites, 57 sites where no further RA is planned, and two sites closed under the Resource Conservation and Recovery Act (RCRA). Seven of the 88 sites have been deferred due to ongoing investigations.
Cleanup Progress
The site contamination is being addressed by several long-term remedial actions. A groundwater pump and treat system was installed in 1981 to clean up a TCE spill near Building 43 and to halt its movement offsite. A second pump and treat system was installed in 1988 to clean up TCE and fuel spills, originating near the operational apron and Building 5008. A third pump and treat system began operation in 1992 to clean up spills at the POL Bulk Storage Area. In 1993, the Air Force connected residents, located between the base and Van Etten Lake, to a potable water supply. A low volume hydrocarbon skimmer operated from 1991 until 1992 to remove spilled jet fuel from the water table. Ex-situ bioremediation was used to clean up excavated soil contaminated with diesel fuel from a leaky underground storage tank in 1991. The Air Force removed all of the storage tanks from the site. The fuel hydrant system and the oil/water separators have been cleaned.
The soils at and near the petroleum, oil, and lubricant bulk storage yard are currently undergoing remediation through soil vapor extraction (SVE) and bioventing to remove organics. The SVE and bioventing systems were installed in November 1999. A biosparging system, installed to cleanup residual fuel from the groundwater in this area, also began operating in 1999.
The air sparging/SVE systems were installed at the Strategic Air Command (SAC) Operational Apron area in November 1999 to treat groundwater contaminated with volatile organics. The system was shut down in November 2001 when cleanup objectives were met. Post-closure monitoring is being conducted to ensure the treatment remains effective.
A SVE system was installed at the Fire Training Area to cleanup soil contaminated with volatile organic compounds (VOCs). The system began operating in May 2001.
Bioventing and biosparging systems were installed at the Base Operational Apron in 2003 to treat soil and groundwater contaminated with petroleum constituents. These systems became operational in 2004.
Northern Landfill Area
Groundwater contaminated in the Northern Landfill Area discharges into Van Etten Lake at the YMCA property boundary. An 80-well barrier air sparging curtain was installed at the base boundary downgradient of the landfills and commenced full-time operations in May 2002. The primary intent of the system is to inject/add oxygen to the subsurface as a means to help restore groundwater table aquifer. In-situ stripping of VOCs is a secondary outcome of air sparging operations. A small groundwater and extraction treatment system was also installed at the base boundary north of the air sparging curtain to capture groundwater contaminated with chlorinated solvents in a narrow plume originating at the landfills that is traveling offsite. Monitoring is being conducted to measure the performance of the systems.
Groundwater from the Northern Landfill area discharging to Van Etten Lake at the YMCA beachfront has caused aesthetic impacts (iron staining) at the beach. Remedial actions performed at the YMCA beach include one sand removal/replacement (April 1999), and three sand placements (January 2001, January 2002, and January 2003). Oxygen Release Compound (ORC) was injected slightly upgradient of the beach to increase the dissolved oxygen levels in the aquifer so that staining would not occur. 4,770 pounds of ORC were injected through through 97 points in February 2001 and 4,860 pounds of ORC were injected through 109 points near the beach in October 2001. Monitoring is being conducted to determine the impacts of the ORC application.
The Air Force is evaluating options for closure of the Landfill 30/Landfill 31 areas and is working with U.S. EPA and the Michigan DEQ on closure requirements. Although the air sparge system continues to operate downgradient of the landfill areas, the Air Force is evaluating options to better address groundwater contamination that moves from the landfill area toward the YMCA beach.
Landfill 27 (LF27)
The Air Force is currently investigating groundwater contamination associated with the LF-27 area. LF-27 primarily contains non-hazardous fill. However, the MDEQ is concerned that low-level metal contamination (esp. manganese ) in groundwater could pose a threat at the groundwater discharge point in Clark’s March. MDEQ is also concerned about aesthetic impacts from “yellow boy” staining from elevated iron concentrations.
Evaluation of Groundwater Treatment Systems
The Air Force is currently evaluating the groundwater “pump and treat” systems in operation (Arrow Street, Benzene Plant, and Mission Street) to ensure that the systems are capturing plume areas and operating efficiently.
Future Site Reviews
A base wide five-year review was completed in September 2004. A second base-wide five year review is planned for 2009.
Studies of the nature and extent of contamination at a few sites are still underway. These investigations will result in the selection of remedies for final cleanup of the site. Cleanup actions, including the operation of groundwater pump and treat systems, the connection to the potable water supply, the operation of the hydrocarbon skimmer, and the ex-situ bioremediation of the soil, have reduced the threat to human health and the environment while site investigations are underway.
Contacts
Remedial Project Manager, U.S. EPAtimothy fischer (fischer.timothy@epa.gov)
(312) 886-5787
Community Involvement Coordinator, U.S. EPA
cheryl allen
(312) 353-6196
Aliases
WURTSMITH USAF BASEUS AIR FORCE WURTSMITH AFB