THE 2007 NPDES PERMIT ISSUED TO PORTSMOUTH AUTHORIZES THE CITY TO DISCHARGE TREATED WASTEWATER FROM OUTFALL 001 MEETING SECONDARY TREATMENT-BASED STANDARDS AND REQUIRES WET-WEATHER DISCHARGES FROM THE CITY'S FOUR COMBINED SEWER OVERFLOW (CSO) OUTFALLS TO RECEIVE A LEVEL OF TREATMENT NECESSARY TO ACHIEVE COMPLIANCE WITH THE FEDERAL OR STATE WATER QUALITY STANDARDS.
THE ORDER CITES THE CITY FOR DISCHARGES FROM THE CITY'S CHEMICALY-ENHANCED PRIMARY WASTEWATER TREATMENT PLANT THAT WILL EXCEED THE 5-DAY BIOCHEMICAL OXYGEN DEMAND (BOD5), TOTAL SUSPENDED SOLIDS (TSS), AND ACUTE WHOLE EFFLUENT TOXICITY (WET) LIMITS CONTAINED IN THE REISSUED PERMIT. ADDITIONALLY, THE ORDER FINDS THAT THE CITY DOES NOT RECORD RESIDUAL CHLORINE ON A CONTINUOUS RECORDER AS REQUIRED BY THE PERMIT, AND THE CSO OUTFALL DISCHARGES CONTAIN BACTERIA IN CONCENTRATIONS THAT CAUSE OR CONTRIBUTE TO VIOLATIONS OF THE STATE WATER QUALITY STANDARDS.
THE ORDER REQUIRES THE CITY TO SUBMIT A TECHNICAL MEMORANDUM SUMMARIZING THE RESULTS OF TASKS AND 2 EVALUATIONS CONTINED IN THE DRAFT WASTEWATER MANAGEMENT PLAN SCOPE OF WORK DATED MAY 2007, AND AN ENGINEERING REPORT THAT RECOMMENDS CORRECTIVE MEASURES REQUIRED TO PREVENT OUTFAL 001, AND IMPLEMENTATION SCHEDULE FOR CSO ABATEMENT PROJECTS FOR 2005 FINAL CSO LONG-TERM CONTROL PLAN.