Association Comments on 2020 Reissuance of Industrial Stormwater MSGP

(June 10, 2020) – NACWA submitted comments June 1 on EPA’s most recent iteration of the multi-sector general permit (MSGP) for stormwater discharges associated with industrial activity.

Traditionally, NACWA’s members that are permitted under the MSGP’s Sector T, Treatment Works section — which includes wastewater plants that have a design flow of more than 1 million gallons per day or are required to have an approved pretreatment program — have not experienced significant compliance issues with the permit’s terms and their stormwater discharges have not had negative impacts on water quality.

However, NACWA has concerns with the proposed 2020 MSGP and the considerable impacts it could have on the municipal clean water community because it adds monitoring requirements and control measures that will not likely result in tangible water quality improvements.

The proposed 2020 MSGP includes new benchmark monitoring requirements for total suspended solids (TSS), pH, and chemical oxygen demand (COD) for all industry sectors covered under the permit. Under previous MSGP iterations, publicly owned treatment works (POTWs) were not required to conduct benchmark monitoring because they are not significant contributors to water quality exceedances.

The new “one-sized fits all” mandates in the proposed MSGP are troubling especially for POTWs that are traditionally low-risk contributors of water quality degradation under the permit.

NACWA also has concerns with other provisions within the proposed permit including language that would require permittees to select specific best management practices or control measures to mitigate extreme flooding.

If members have questions, contact Emily Remmel, NACWA’s Director of Regulatory Affairs.