THIS REFERRAL REQUESTS THAT A COMPLAINT BE FILED AGAINST POTENTIALLY RESPONSIBLE PARTIES AT THE MASON COUNTY LANDFILL SITE, PURSUANT TO SECTION 107A OF THE CERCLA. - LOCATED NEAR LUDINGTON, MI, THE MASON COUNTY LANDFILL SITE WAS PLACED ON THE NATIONAL PRIORITIES LIST IN 1982. THE U.S. EPA COMPLETED A REMEDIAL INVESTIGATION AND FEASIBILITY STUDY AT THE SITE IN JULY, 1988, AND ISSUED A RECORD OF DE- CISION THAT AUGUST. IN APRIL, 1989, THE U.S. EPA ISSUED A UNILATERAL ORDER TO THE COUNTY OF MASON FOR REMEDIAL ACTION AND REMEDIAL DESIGN, AFTER NEGOTIATIONS FOR A CONSENT DECREE FAILED. AS OF DECEMBER 31, 1989, THE U.S. EPA HAS INCURRED $942,190 IN UNREIMBURSED COSTS REGARDING THE SITE. PURSUANT TO SECTION 113G OF CERCLA, AN ACTION FOR THE RECOVERY OF COSTS REFERRED TO IN SECTION 107A OF CERCLA MUST BE COM- MENCED WITHIN 6 YEARS AFTER INITIATION OF PHYSICAL ON-SITE CONSTRUCTION OF THE REMEDIAL ACTION. USEPA IS, THEREFORE, REFERRING THIS COST RECOVERY LAWSUIT SEEKING ALL OF USEPA'S UNREIMBURSED PAST COSTS.