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Storm Water Permit Applicability and No Exposure Certification

State and federal rules require that a facility apply for industrial storm water permit coverage if storm water exposed to industrial materials discharges to surface waters. This requirement also includes facilities that discharge storm water to a municipal separate storm sewer system (MS4). As a refresher, your facility requires storm water permit coverage if you can answer all of the following three items affirmatively:

  • The facility’s primary Standard Industrial Classification (SIC) code must be included. Common included SIC codes include manufacturing (SIC 20xx to 39xx) and transportation (SIC 40xx to 45xx).

  • Storm water must discharge to surface waters (or a MS4) through a point source.

  • Industrial materials must be exposed to precipitation.

If the facility does not have an included SIC code or does not discharge to surface waters or does not expose industrial materials, a storm water permit coverage is not required. If the first two apply but not the third, a No Exposure Certification (NEC) must be submitted to avoid permitting.

Regarding the NEC, if your facility stores or handles industrial materials outside without a storm resistant shelter your facility is considered to have exposure. Exceptions do exist, but the term exposure describes the potential for precipitation to come in contact with industrial materials. Industrial materials may include material handling equipment (bins, boxes, pallets, racking, etc.), machinery, raw materials, intermediate products, byproducts, final products, and waste products.

The intent of the no exposure exclusion is to promote a condition of permanent no exposure. There are a couple of items that are permissible that will not prevent a facility from submitting an NEC and a storm-resistant shelter is not required.

  • Drums, Barrels, Tanks, and Similar Containers: Drums, barrels, tanks, and similar containers that are sealed (“sealed” means banded or otherwise secured and without operational taps or valves) are considered not exposed if stored outdoors provided those containers are not deteriorated, do not leak, and have no material residues on the outsides of the containers. Any time containers are not sealed, begin to deteriorate, or start leaking, they must be moved indoors or placed inside a permanent storm-resistant shelter. Containers, racks, and other transport platforms such as wooden pallets used with the drums, barrels, etc., can also be stored outside providing they are contaminant-free.

  • Lidded Leak-Proof Containers and Compactors: Lidded leak-proof containers (dumpsters) and compactors containing waste or recyclable materials may meet the definition of no exposure if the containers are managed so that no material can drain, spill, leak, or otherwise be released from the containers. Any material lost during handling or by loading containers onto vehicles for transport is considered exposed. In addition, industrial refuse and trash that is stored uncovered is considered exposed.

At some facilities, these two items may be the only industrial materials subject to storm water contact. If that’s the case, the NEC form can be submitted to avoid permitting or even as a termination request. Note that the condition of “No Exposure” is conditional and must be maintained. Therefore, if there is a change in circumstances that causes exposure of industrial activities or materials to storm water, the facility is required to comply immediately with all requirements of the storm water program, including obtaining a permit.

It is CFR’s experience that due to the difficulty of meeting and maintaining a condition of “no exposure” for these items, storm water coverage may be the best path forward.

Not comfortable operating without required storm water permit coverage? CFR has been providing regulatory support and storm water program development services since program development in the 1990s. Contact CFR to learn how we can guide you through meeting your storm water requirements.

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