GARDINIER OWNS AND OPERATES A PHOSPHATE FERTILIZER PRO- DUCTION FACILITY LOCATED ADJACENT TO THE ALAFIA RIVER IN HILLBOROUGH COUNTY, FLORIDA. ON APRIL 30, 1988, AT APPROXIMATELY 9:00 P.M. LOCAL TIME, A UTILITY OPERATOR AT GARDINIER INITIATED A PHOSPHORIC ACID SHIFT PROCESS BETWEEN TWO TANKS LOCATED ON THE FACILITY. DUE TO OPERATOR ERROR, A CROSS-OVER VALVE WAS NOT PLACED IN THE CLOSED POSITION DURING THIS SHIFT CAUSING PHOSPHORIC FETILIER SOLUTION (PFS) TO OVERFLOW OUT OF ONE OF THE TANKS AND INTO THE CONCRETE CONTAINMENT AREA VIA A CRACK IN THE CONTAINMENT STRUCTURE AND FLOWED INTO NEARBY DITCHES. THREE UNDERGROUND CULVERTS THEN CARRIED THE PFS DIRECTLY INTO THE ALAFIA RIVER. PRE-REFERRAL NEGOTIATIONS SOUGHT FOR VIOLATION FO SECTION 311 OF THE CWA. FIFTY THOUSAND DOLLARS IS BOTTOM-LINE AMOUNT SOUGHT.