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National Pollutant Discharge Elimination System (NPDES)

Stormwater Discharges from Industrial Activities-Conditional "No Exposure" Exclusion

Remember to throw your gloves in the trash

An industrial facility with its industrial materials and activities protected by a storm resistant shelter to prevent exposure to rain, snow, snowmelt, and/or runoff is eligible for an exemption from NPDES industrial stormwater permit requirements. Industrial materials and activities include:

  • material handling equipment and activities,
  • industrial machinery,
  • raw materials,
  • intermediate and final products,
  • by-products, and
  • waste products.

The conditional no exposure exclusion applies to 10 of the 11 categories of stormwater discharges from regulated industrial activities:

  • Category One: Facilities subject to federal stormwater effluent discharge standards in 40 CFR Parts 405-471
  • Category Two: Heavy manufacturing (e.g., paper mills, chemical plants, petroleum refineries, and steel mills and foundries)
  • Category Three: Coal and mineral mining, and oil and gas exploration and processing
  • Category Four: Hazardous waste treatment, storage or disposal facilities
  • Category Five: Landfills, land application sites, and open dumps with industrial wastes
  • Category Six: Metal scrapyards, salvage yards, automobile junkyards, and battery reclaimers
  • Category Seven: Steam electric power generating plants
  • Category Eight: Transportation facilities that have vehicle maintenance, equipment cleaning or airport deicing operations
  • Category Nine: Treatment works treating domestic sewage with a design flow of 1 million gallons or more a day
  • Category Eleven: Light manufacturing (e.g., food processing, printing and publishing, electronic and other electrical equipment manufacturing, and public warehousing and storage)

The exclusion does not apply to Category Ten, which is stormwater discharges from construction sites that disturb five or more acres. They are permitted separately under the NPDES stormwater program.

No Exposure Certification

A no exposure certification must be provided to the permitting authority for each facility qualifying for the permitting exclusion. In addition, the exclusion from NPDES permitting is available on a facility-wide basis only, not for individual outfalls. To retain the exclusion, you must recertify the condition with the permitting authority at least every five years. If you are in an area where EPA is the permitting authority, you can use the NPDES eReporting Tool for the MSGP (NeT-MSGP) to submit your no exposure certification.

If any industrial materials or activities are or will be exposed to precipitation, your facility is not eligible for the no exposure exclusion, and you must obtain NPDES stormwater permit coverage.

Additional Information

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