WITHIN 30 DAYS OF THE EFFECTIVE DATE OF THIS AGREEMENT, FRED WILCOX SHALL PAY TO THE EPA HAZARDOUS SUBSTANCE SUPERFUND $18,500 IN PARTIAL REIMBURSEMENT OF CERTAIN UNRECOVERED PAST RESPONSE COSTS TOTALLING $222,025.90, PLUS AN ADDITIONAL SUM FOR INTEREST ON THAT AMOUNT &$18,500) CALCULATED FROM THE DATE SET FORTH IN THE DEFINITION OF PAST RESPONSE COSTS THROUGH THE DATE OF PAYMENT. IF ANY AMOUNTS DUE TO EPA ARE NOT PAID BY THE REQUIRED DATE, FRED WILCOX SHALL PAY TO EPA, AS A STIPULATED PENALTY, $100 PER VIOLATION PER DAY THAT SUCH PAYMENT IS LATE.