THE SITE WAS AN OIL RECOVERY FACILITY, WHICH WAS IN OPERATION FROM APPROX. 1978 TO 1996. DURING THE YEARS OF OPERATION, WASTE OILS WERE COLLECTED AND CARRIED TO THE SITE, WHERE A GRAVITY SEPARATION SYSTEM WAS USED TO RECOVER OILS FOR RESALE. THE UNUSED OIL REMAINING AFTER THIS SEPARATION PROCESS APPEARS TO HAVE BEEN RELEASED ONTO THE GROUND AT THE SITE OR LEFT IN CONTAINMENT VESSELS. IN 1995, REGION 4 CONDUCTED A SPILL PREVENTION, CONTROL, AND COUNTERMEASURE (SPCC) COMPLIANCE INSPECTION AT THE SITE. THE SPCC NOTED NUMEROUS SITE DEFICIENCIES. IN FEBRUARY 1996, REGION 4 CONDUCTED A REMOVAL SITE EVALUATION (RSE). THE RSE FOUND EVIDENCE OF A RELEASE OF HAZARDOUS SUBSTANCES AT THE SITE. RSE SAMPLE RESULTS REVEALED THE PRESENCE OF THE HAZARDOUS SUBSTANCES: TETRACHLOROETHYLENE; TRICHLOROETHANE; LEAD; BENZENE; CHROMIUM; AND PCBS. REGION 4 DETERMINED THAT THE SITE POSED AN IMMINENT AND SUBSTANTIAL THREAT TO HUMAN HEALTH AND THE ENVIRONMENT.