Water pollution from factory farms is regulated under the federal Clean Water Act. A 2008 rule issued by the U.S. Environmental Protection Agency requires factory farms that discharge animal waste into waterways to obtain a National Pollutant Discharge Elimination System (NPDES) permit. This wastewater permit sets limits on the pollution that a factory farm can discharge into nearby surface waters. Discharges can come from animal holding pens, waste holding structures, and the fields where waste is applied as fertilizer. Nevertheless, best management practices should be implemented and maintained to minimize the amount of pollution leaving factory farms.
In Illinois, the Illinois Environmental Protection Agency (IEPA) is responsible for issuing NPDES permits to factory farms and enforcing permit requirements. Most applicants will seek the general NPDES permit, which prohibits discharges except during particularly heavy storm events (25-year, 24-hour storms). More information about IEPA’s CAFO program, including a copy of the State’s general NPDES permit, can be found at www.epa.state.il.us/water/cafo/index.html.
Illinois has thousands of factory farms, but fewer than 50 have NPDES permits. You can find out if a factory farm near you has a permit to pollute by checking IEPA’s permit database.