DESCRIPTION OF VIOLATION: SOUTH ESSEX SEWERAGE DISTRICT (SESD) OPERATES A WASTE- WATER TREATMENT FACILITY LOCATED IN SALEM, MASS. IN ADDITION TO SALEM, SESD SERVICES THE SURROUNDING MUNICIPALITIES OF BEVERLY, DANVERS, MARBLEHEAD, AND PEABODY. THE SEWAGE FROM THIS SERVICE AREA RESULTS IN THE PRODUCTION OF APPROX 250 WET TONS OF SLUDGE PER DAY. SINCE FEB 3, 1980, SESD HAS BEEN DISCHARGING THIS SLUDGE INTO SALEM SOUND ON THE OUTGOING TIDE. THIS PRACTICE RESULTS IN VIOLATIONS OF THE SEWERAGE DISTRICT'S NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM (NPDES) PERMIT AND SUBJECTS SESD TO FEDERAL ENFORCEMENT AC- TION PURSUANT TO SECT.309 OF THE CLEAN WATER ACT, 33 U.S.C. SECT.1319. DESCRIPTION OF SOURCE: SESD'S WASTEWATER TREATMENT PLANT IS DESIGNED TO PROVIDE PRIMARY TREATMENT OF DOMESTIC, COMMERCIAL AND INDUSTRIAL WASTEWATER FOLLOWED BY INCINERATION OF THE RESULTING SLUDGE AND DISPOSAL OF THE INCINERATOR ASH. THE CURRENT VIOLATION OF THE CWA IS CAUSED BY SESD'S FAILURE TO OPERATE ITS SLUDGE INCINERATORS. THE INCINERATORS WERE SHUT DOWN ON FEB 3, 1980 DUE TO MECHANICAL DIFFICULTIES. IN ADDITION, ON JAN 23 '80, ONLY A FEW DAYS PRIOR TO SHUT DOWN, THE MASS. DEPT OF ENVIR- ONMENTAL QUALITY ENGINEERING (DEQE) DECLARED THE ASH PRO- DUCED IN SESD'S INCINERATORS A HAZARDOUS WASTE, BECAUSE HAZ- ARDOUS LEVELS OF HEXAVALENT CHROMIUM