As of February, new or replacement surface discharge septic systems in Illinois require a general permit from the U.S. Environmental Protection Agency if they discharge to the “waters of the United States,” to conform to national standards. The EPA says its definition of the term includes “among other things, traditional navigable waters, tributaries of traditional navigable waters, and wetlands that are adjacent to traditional navigable waters or their tributaries.” Anyone not eligible for the general permit may apply for an individual permit from the state EPA.The federal permits, issued under the National Pollutant Discharge Elimination System, also set discharge limits
