Minn. Stat. § 115.456: COMPLIANCE SCHEDULES.

The commissioner of the Pollution Control Agency must consider current debt service on existing municipal wastewater treatment infrastructure when developing compliance schedules for new effluent limits in municipal national pollutant discharge elimination system (NPDES) permits. Any compliance schedule for new effluent limits in municipal NPDES permits must be developed in a manner consistent with state and federal law to maximize the repayment of existing debt on wastewater infrastructure before requiring additional capital infrastructure upgrades. To the extent allowable under federal law, the commissioner may issue compliance schedules in municipal NPDES permits for new effluent limit requirements in excess of 20 years.