Lake Benton Wastewater Treatment Facility - Wastewater Permit

We invite you to comment on the draft wastewater permit for the Lake Benton wastewater treatment facility.

The existing facility has a controlled discharge from SD 001. The facility is a Class D.

The facility is designed to treat:

• an average wet weather (AWW) flow of 0.318 million gallons per day (mgd); and
• a five-day biochemical oxygen demand (BOD5) of 91 milligrams per liter (mg/L).

The facility consists of two (2) 5.5-acre primary stabilization ponds and one (1) 4.0-acre secondary stabilization pond, each measured at the three-foot depth level. The pond system provides a total detention time of 61 days at permitted AWW flow.

Water quality permits - or National Pollutant Discharge Elimination System (NPDES) permits - establish specific limits and requirements to protect Minnesota's surface and groundwater quality. Permits are regularly reviewed and updated as they expire, allowing the MPCA to incorporate new information about the impacts of pollutants on the environment in future permits. Permits are enforced through a combination of self-reporting and compliance monitoring.