ON 10/21/80, THE US DISTRICT CT FOR THE DISTRICT OF IDAHO ENTERED A STIPULATION AND CD IN SETTLEMENT OF A CLEAN WATER ACT CIVIL ACTION THAT THE US HAD FILED AGAINST THE CITY OF TWIN FALLS ON 9/10/76. THE CIVIL ACTION HAD BEEN TAKEN IN RESPONSE TO RECURRENT DISCHARGES OF UNTREATED WASTEWATER AND OTHER SERIOUS VIOLATIONS OF THE CITY'S NPDES PERMIT IN THE OPERATION OF ITS MUNICIPAL TREATMENT PLANT. THE 1980 CD, AS MODIFIED BY A 6/30/82 STIPULATION, RE- QUIRED THE CITY TO PROMPLY CARRY OUT CONSTRUCTION OF NEW TREATMENT FACILTIES (FUNDED LARGELY BY AN EPA CONSTRUCTION GRANT), NEET SPECIFIED INTERIM AND FINAL EFFLUENT LIMITS, AND MAINTAIN AN ADEQUATE STAFF TO OPERATE ITS TREATMENT PLANT. TWIN FALLS VIOLATED EACH OF THESE REQUIREMENTS. STIPULATED PENALTIES WERE PROVIDED FOR VIOLATIONS OF THE DECREE. A FORCE MAJEURE SECTION OF THE 10/21/80 DECREE WOULD EXCUSE A CONSIDERABLE NUMBER OF THESE VIOLATIONS, PARTICULARLY THE CITY'S DELAYS IN COMPLETING CONSTRUCTION OF ITS EXPANDED TREATMENT PLANT. OTHER VIOLATIONS, HOWEVER, SUCH AS EFFLUENT VIOLATIONS CAUSED BY HEAVY INFLUENT LOAD- INGS TO THE TREATMENT PLANT FROM LOCAL INDUSTRY, WERE CAUSED BY FACTORS WITHIN THE CITY'S CONTROL. ASSESSMENT OF STIPULATED PENALTIES FOR THESE VIOLATIONS BOTH EFFECTUATES EPA'S DUTY TO THE COURT TO ASSURE COMPLIANCE WITH THE CD.