Industrial wastewater

Scope

Wastewater discharges from industrial and commercial facilities may be contaminated with pollutants that could negatively affect surface waters or publicly owned treatment works (POTWs). EPA sets limits on the pollutants that may be discharged from industrial sources through the National Pollutant Discharge Elimination System (NPDES) permitting program. Many states have been authorized to run their own wastewater permitting program and must meet these limitations.

Industrial and commercial sources that discharge wastewater directly to receiving waters will need to obtain an individual or general NPDES permit. However, industrial and commercial sources that discharge wastewater to the municipal sewer system (indirect dischargers) will be covered by the NPDES pretreatment program.

Regulatory citations

• 40 CFR 122 — EPA administered permit programs: The national pollutant discharge elimination system
• 40 CFR 401 — General provisions
• 40 CFR 403 — General pretreatment regulations for existing and new sources of pollution
• 40 CFR 400-471 — Effluent guidelines and standards

Key definitions

• Continuous discharge: A “discharge” which occurs without interruption throughout the operating hours of the facility, except for infrequent shutdowns for maintenance, process changes, or other similar activities.
• Discharge of a pollutant:
  • Any addition of any “pollutant” or combination of pollutants to “waters of the United States” from any “point source,” or
  • Any addition of any pollutant or combination of pollutants to the waters of the “contiguous zone” or the ocean from any point source other than a vessel or other floating craft which is being used as a means of transportation.
  This definition includes additions of pollutants into waters of the United States from: surface runoff which is collected or channeled by man; discharges through pipes, sewers, or other conveyances owned by a state, municipality, or other person which do not lead to a treatment works; and discharges through pipes, sewers, or other conveyances, leading into privately owned treatment works. This term does not include an addition of pollutants by any “indirect discharger.”
• Effluent limitation: Any restriction imposed on quantities, discharge rates, and concentrations of “pollutants” which are “discharged” from “point sources” into “waters of the United States,” the waters of the “contiguous zone,” or the ocean.
• Effluent limitations guidelines: A regulation published under section 304(b) of the Clean Water Act to adopt or revise “effluent limitations.”
• Facility or activity: Any NPDES “point source” or any other facility or activity that is subject to regulation under the NPDES program.
• Indirect discharger: A facility that introduces pollutants to a publicly owned treatment works.
• Non-process wastewater: Any water used for purposed other than processing products.
• Process wastewater: Any water which, during manufacturing or processing, comes into direct contact with, or results from the production or use of any raw materials, intermediate product, finished product, byproduct, or waste product.

Summary of requirements

• Determine if your facility discharges a pollutant in your wastewater.
• Check with your state water permitting agency or federal EPA to see if you need a permit for your wastewater.
• Determine if you need a general or individual wastewater permit.
• Apply for the permit.
• Comply with the permit.