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National Pollutant Discharge Elimination System (NPDES)

Sanitary Sewer Overflows (SSOs) and Peak Flow Listening Sessions and Workshop

In 2010, EPA requested and received stakeholder input on whether, and how, to modify the NPDES regulations as they apply to municipal sanitary sewer collection systems and SSOs. The Agency also received input on issues associated with diversions at wastewater treatment plants that are recombined with the flows from biological treatment units prior to discharge.

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