The Indiana Department of Environmental Management (IDEM) recently announced that National Pollutant Discharge Elimination System (NPDES) permits submitted for renewal or modification after January 1, 2019 will include total nitrogen monitoring requirements for sanitary dischargers who have a 1.0 MGD average design flow or greater. With the inclusion of total nitrogen monitoring in NPDES permits, it’s important to understand why nitrogen is being monitored and what is being required by IDEM.
