August 1997 Former Firefighter Training Area 1 The purpose of this fact sheet is to describe treatment activities at one of the source areas at the Massachusetts Military Reservation (MMR). The Former Firefighter Training Area 1 (FTA-1) site is one of the source areas for the Ashumet Valley groundwater plume emanating from the base. Cleanup of the FTA-1 source area is an important component of remediating the Ashumet Valley groundwater plume. Once the contaminated soils at the site are cleaned, this source area will no longer contribute contaminants to the plume. Site History FTA-1 is located approximately 500 feet north of Kittredge Road, near the southern boundary of the Massachusetts Military Reservation (MMR). The level, cleared, 3-acre site was used for firefighter-training exercises between 1958 and November 1985. In 1985, the site was closed to further fire-training activities because of air emission permitting difficulties. All burning occurred on the ground surface prior to 1983, when a concrete pad with a soil berm border was built to contain flammable liquids. Flammable materials burned in this area include various fuels, oils, solvents, thinners, and hydraulic fluids. Site Remediation A remedial investigation was completed in 1991 to determine the nature and extent of contamination at FTA-1 and to determine the relationship of the site to the Ashumet Valley plume. Thermal treatment of contaminated soils was identified as the preferred alternative for treating contamination at the site. Currently, thermal treatment involves a heat transfer system consisting of two chambers, each containing two large, hollow, metal corkscrews. This "jacketed screw conveyor" has a special oil that flows inside the corkscrews. The oil is heated to 600 degrees Fahrenheit. Excavated soil is placed in the chamber and, as the corkscrews turn the soil, heat transfers to the soil, which turns the fuel and solvents in the soil into vapor. The fuel and solvents contained in the vapor are removed by passing the vapor through a granular activated carbon filter. Expended carbon filters are recycled off-Cape. Several air quality monitoring stations located around the site to evaluate the performance of the systems to protect public health during excavation and treatment of soils. Treatment of contaminated soils at the FTA-1 site began in June 1995. Approximately 22,000 tons of soil were excavated and treated between June 1995 and May 1996. In 1996, a new contract for continuing remediation services was awarded to Jacobs Engineering Group, and treatment resumed in January 1997. Soil treatment was delayed in 1997 as a result of a fire on February 26. The fire, caused by a leak within the system, caused significant damage to the treatment units. The fire was contained and did not affect the surrounding site. At the time of the fire, approximately 10,000 additional tons of soil had been treated.
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