On April 5, 2017, the Illinois Environmental Protection Agency (Illinois EPA) issued a final version of the Renewal of the Illinois General National Pollutant Discharge Elimination System (NPDES) Permit for Storm Water Discharges from Industrial Activities (General Permit). Notable changes include new quarterly facility inspections, new "benchmark" performance standards for certain industry sectors, new Total Maximum Daily Load (TMDL) discharge requirements, modified employee training, additional control measures to minimize exposure of processes to storm water, and modified Storm Water Pollution Prevention Plan (SWPPP) contents. Additional details on the final Renewal General Permit are available here.

As previously identified, the revised General Permit requires quarterly facility inspections rather than annual facility inspections, in addition to the quarterly visual observations. Conservatively, it was assumed that facilities covered under the revised General Permit were to begin these quarterly facility inspections immediately following the permit effective date of April 5, 2017. However, recent guidance has been provided by Illinois EPA, clarifying that permittees can maintain their current observation and inspection schedules until October 2, 2017 (the date by which a revised SWPPP addressing any new requirements under the General Permit must be submitted). As such, the first quarterly facility inspection is due to be completed by December 31, 2017.