Special Exemptions of NPDES Permits

A number of types of discharges that meet the definition of a "point" source are not required to obtain an NPDES permit because of either statutory (congressional) or administrative (EPA) exemptions. These include the following:

• Some abandoned mines on nonfederal lands (state, local, private)

• Sewage (not other types of discharges) from ships covered by the EPA's Vessel Sewage Discharge Program

• Return flows from irrigated agriculture

• Most drainage ditches associated with logging roads

• Most smaller feedlots and aquaculture facilities

• Indirect discharges

When wastewater from a site is sent to the wastewater treatment plant (POTW) via city’s sewer system, it is called an indirect discharger and is not regulated under NPDES. However, indirect dischargers are covered by Pretreatment Program in CWA. Click here to compare the direct discharge and indirect discharge.

Copyright @ January,2005 Prepared by Transportation Environmental Resource Center (TERC)