THERE HAVE BEEN A BROAD RANGE OF EFFULENT-RELATED VIOLATIONS FROM AT LEAST 1985 UNTIL THE PRESENT TIME AT THE COLUMBIA AVE PLANT. THESE INCLUDE VIOLATIONS OF NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM PERMIT LIMITS FOR BIOCHEMICAL OXYGEN DEMAND, SUSPENDED SOLIDS, FECAL COLIFORM, TOTAL RESI- DUAL CHLORINE, DISSOLVED OXYGEN, OIL AND GREASE, A NUMBER OF METALS, AMMONIA NITROGEN, AND PHENOLS. IN SHORT, ESSENTIAL- LY ALL POLLUTANT PARAMETERS LIMITED IN THE PERMIT. - THE HAMMOND TREATMENT PLANT AN SEWER SYSTEM HAVE BEEN THE SOURCE OF NUMEROUS DRY WEATHER BYPASSES AND COMBINED SEWER OVERFLOWS FROM AT LEAST 1985 UNTIL THE PRESENT. - THE SUM AND SUBSTANCES OF THESE TWO BASIC, ENVIRONMENTAL PROBLEMS HAS LED TO THE SEVERE DEGRADATION OF THE GRAND AND LITTLE CALUMET RIVERS. - A COMPLICATING FACTOR, WITH RESPECT TO THE DRY WEATHER BYPASSING, HAS BEEN THAT A NUMBER OF PLANT IMPROVEMENTS THAT HAVE BEEN UNDERTAKEN WITHIN THE LAST SEVERAL YEARS DID NOT TAKE THESE FLOWS INTO CONSIDERATION WHEN THE IMPROVEMENTS WERE DESIGNED. AS A RESULT, THE COLUMBIA AVE. PLANT MAY BE UNDERSIZED, AND NOT CAPABLE OF FULLY TREATING ALL INCOMING FLOWS TO THE PLANT. -