FROM 1958 TO 1985 THE SITE PROPERTY IN QUESTION HAS BEEN OWNED BY DASCO PRODUCTS CO. IN 1985, THE PROPERTY WAS SOLD TO AIRCRAFT TOOL SUPPLY, WHICH IS THE CURRENT OWNER. DURING THE 1960'S THE THOMPSON CORPORATION OPERATED THE SITE, EN- GAGING IN THE ASSEMBLY OF ANTI-RATTLE DEVICES FOR THE AUTO- MOBLE INDUSTRY. IN 1970, AMTEL INC., ACQUIRED THE ASSETS OF THE THOMPSON CORP. IN CONDUCTING PRODUCTION OPERATIONS, THE THOMPSON CORP USED TRICHLOROETHYLENE AS A DEGREASING SOLVENT FROM AT LEAST 1968 TO 1972, 40 TO 45 GALS PER BATCH OF SPENT TRICHLOROETHYLENE WAS DUMPED ONTO THE GROUND EVERY 2 WEEKS. IN 1974, AMTEL INC SOLD THE THOMPSON CORP TO HEDBLUM INDUS- TRIES. - HEDBLUM INDUSTRIES DISCHARGED SPRAY TANK RINSE WATER AND COOLING WATER FROM A JACKET AROUND THE DEGREASER TANK TO THE GROUND SURFACE. SINCE THESE WATER SUPPLIES ORIGINATED FROM ON-SITE WELLS, CONTAMINATION OF THE WATER DISCHARGES WITH TRICHLOROETHYLENE WAS SUSPECTED. IN 1979, HEDBLUM INDUSTRIES CHANGED ITS NAME TO RPI, INC. AND MOVED TO ANOTHER SITE. IN 1982, NUTEK LEASED THE SITE. IN 1983, RPI INC CHANGED ITS NAME TO ATS LIQUIDATION TO FACILITATE THE SALE OF THE BUSINESS TO A NEW CORPORATION OWNED BY ITS MANAGEMENT WHICH TOOK THE NAME RRI, INC. - CONTAMINATION OF THE GROUNDWATER ARO