What Is An “Illicit Discharge”?
Federal regulations define an illicit discharge as “…any discharge to an Municipal Storm Sewer System (MS4) that is not composed entirely of stormwater…” with some exceptions. These exceptions include discharges from NPDES-permitted industrial sources and discharges from fire-fighting activities. Illicit discharges are considered “illicit” because MS4s are not designed to accept, process, or discharge such non-stormwater wastes. Note: LaRC’s storm system is considered an MS4 and has permitting as such.
Some examples of illicit discharges include:
- Disposal of vehicle maintenance fluids into a storm drain;
- Hosing or washing loading areas in the vicinity of storm drain inlets;
- Leaking dumpsters flowing into a storm drain inlet;
- Old and damaged sanitary sewer line leaking fluids into a cracked or damaged storm sewer line;
- Illegal dumping;
- Allowing unauthorized wash water with soaps or detergents into a storm drain inlet;
- Washing silt, sediment, concrete, cement or gravel into a storm drain; and/or
- A measurable flow during dry weather that contains pollutants or pathogens.
Examples of illicit discharges.
Illicit discharges are prohibited via Langley Procedural Requirements (LPR) 8500.1, also known as the “Environmental Program Manual.” The following statement is now the Center’s policy in LPR 8500.1 Section 5.2.3.1:
“5.2.3.1 The “Illicit Discharge Detection and Elimination” minimum control measure of the State’s General MS4 Permit requires the Center to effectively prohibit non-stormwater discharges into the storm sewer system and implement appropriate enforcement procedures and actions. LaRC defines an illicit discharge as any discharge to the MS4 that is not composed entirely of stormwater, except for discharges allowed under the Center’s VPDES permit, a discharge approved by DEQ in writing as a de minimis discharge that does not contain a significant amount of pollutants, waters used for firefighting operations/line flushing, and A/C condensate. Illicit discharges are not allowed on the Center and are subject to an array of enforcement actions.”
All employees shall report any suspected illicit discharges and/or illegal dumping activities by contacting the Environmental Management Office (EMO).
REPORT POLLUTION, ILLICIT DISCHARGES, and ILLEGAL DUMPING
*Please report the location and leave as much information as possible. This will allow EMO staff to respond promptly. The information you provide will be confidential*.
Other resources available:
- Learn about LaRC’s MS4 Permit
- View LaRC’s Water Quality Outreach
Note: This page links to PDF files. Use this link to download Adobe Reader if needed.
