Storm Water Permit Program Excludes Certain Transportation Facilities

Under the conditional no exposure exclusion, operators of transportation facilities have the opportunity to certify to a condition of "no exposure" if their industrial materials and operations are not exposed to storm water. As long as the condition of "no exposure" exists at a certified facility, the operator is excluded from National Pollutant Discharge Elimination System industrial storm water permit requirements.

The conditional no exposure exclusion replaces the no exposure exemption described under the Phase I Storm Water Program.

The intent of the no exposure provision is to provide facilities with industrial materials and activities that are entirely sheltered from storm water a simplified way of complying with the storm water permitting provisions of the Clean Water Act. This includes facilities that are located within a larger office building or facilities at which the only items permanently exposed to precipitation are roofs, parking lots, vegetated areas and other non-industrial areas or activities.

The Phase II regulatory definition of "no exposure" follows.

• No exposure means all industrial materials and activities are protected by a storm resistant shelter to prevent exposure to rain, snow, snowmelt and/or runoff. Industrial materials or activities include, but are not limited to, material handling equipment or activities, industrial machinery, raw materials, intermediate products, by-products, final products or waste products.

A storm resistant shelter is not required for the following industrial materials and activities:

• Drums, barrels, tanks and similar containers that are tightly sealed, provided those containers are not deteriorated and do not leak. "Sealed" means banded or otherwise secured and without operational taps or valves;
• Adequately maintained vehicles used in materials handling and
• Final products, other than products that would be mobilized in storm water discharges (e.g., rock salt).

The term "storm-resistant shelter," as used in the no exposure definition, includes completely roofed and walled buildings or structures, as well as structures with only a top cover but no side coverings, provided material under the structure is not otherwise subject to any run-on and subsequent runoff of storm water.

While the intent of the no exposure provision is to promote a condition of permanent no exposure, certain vehicles could become temporarily exposed to rain and snow while passing between buildings. Adequately maintained mobile equipment (e.g., trucks, automobiles, forklifts, trailers or other such general purpose vehicles found at the industrial site that are not industrial machinery and that are not leaking contaminants or are not otherwise a source of industrial pollutants) can be exposed to precipitation or runoff. Such activities alone would not prevent a facility from certifying to no exposure.

Similarly, trucks or other vehicles awaiting maintenance at vehicle maintenance facilities that are not leaking contaminants or are not otherwise a source of industrial pollutants, are not considered "exposed."

For more information, visit the U.S. EPA's Conditional No Exposure Exclusion Web site.