Industrial Pretreatment Program
The City of Raleigh Industrial Pretreatment Program permits, inspects, and surveys customers who may be discharging industrial wastewater. Pretreatment refers to the treatment of non-domestic wastewater before it is discharged to the wastewater treatment plant, also known as a POTW, or publicly-owned treatment works.
What is Industrial Pretreatment?
Pretreatment refers to the treatment of non-domestic wastewater before it is discharged to the wastewater treatment plant, also known as a POTW, or publicly-owned treatment works.
Wastewater treatment plants are designed to handle wastes from a typical household, not the wastes from an industry or business. Certain customers must be issued a permitted under the City of Raleigh Industrial Pretreatment Program because of the large amounts of wastewater discharged or the potential their wastewater has to adversely impact the POTW. To control pollutants, certain industrial users may be required to pretreat their wastewater prior to discharge to sewer. Through pretreatment, the wastewater customer is able to reduce, eliminate, or alter a pollutant before it is introduced into the POTW.
Program objectives are:
- Prevent interference with POTW operations;
- Prevent contamination of the POTW’s biosolids;
- Prevent pass-through to the POTW’s receiving stream;
- Prevent exposure of POTW workers to chemical hazards.
Raleigh’s Pretreatment Program is an EPA federally-mandated program under the administration of the State of North Carolina PERCS Unit with the City of Raleigh as the Control Authority.
Industrial User Permit Information
Prior to discharging industrial waste to the City of Raleigh sewer system, please contact the City of Raleigh Industrial Pretreatment Program. Staff will discuss your operation and a permit application will be sent if approval is necessary. An Industrial User Permit application and a short Industrial Waste Survey form are linked below.
Dental Amalgam Program
On July 14, 2017, the U.S. EPA promulgated the Dental Effluent Guidelines (40 CFR 441) to reduce discharges of mercury and other metals from dental offices into publicly owned treatment works (POTWs). Dental amalgam contains mercury in a concentrated form that is relatively easy to collect and recycle.
All dental facilities subject to this regulation are required to install an amalgam separator that meets the ISO 11143 criteria, implement two Best Management Practices (BMPs), submit a One-Time Compliance Report to the City of Raleigh Industrial Pretreatment Program, and to conduct ongoing operation and maintenance of the amalgam separator and maintain associated documentation and records.
All industrial users of the POTW are subject to industrial waste surcharges on discharges which exceed the following levels:
- BOD greater than 300 mg/l
- TSS greater than 250 mg/l
- Total Nitrogen greater than 30 mg/l
- Total Phosphorus greater than 5 mg/l
Industrial users are also subject to permit application fees, permit modification fees, and annual administrative fees. Rates are subject to change annually. For updated surcharge information, please contact the Industrial Pretreatment Coordinator.