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Storm Water Compliance Series: No Exposure Certification for Exclusion from NPDES Storm Water Permitting

Saturday, November 21, 2015


No Exposure Certification for Exclusion from NPDES Storm Water Permitting
by Patrick A. Kneip, PE & Emma Clohessy


This is the third article in PSARA’s Storm Water Compliance Series.

Compliance with any state’s storm water permitting requirements is most easily achieved by applying for a No Exposure Certification. This certification is a conditional certification—it is not an exemption, and it must be updated/resubmitted every five years. Additionally, each facility in a given company must apply for the No Exposure Certification as it is facility-specific. Below is an example from Ohio of the number of facilities issued No Exposure Certifications over the past several years.



Per the application form, “A condition of no exposure exists at an industrial facility when all industrial materials and activities are protected by a storm resistant shelter to prevent exposure to rain, snow, snowmelt, and/or runoff.” To qualify for a No Exposure Certification, a facility must meet eleven criteria; these criteria are included below in italics, with PSARA’s interpretation bolded below each item.

In the present and in the foreseeable future, none of the following eleven areas or materials may  be exposed to precipitation.

1. Areas where the facility uses, stores, or cleans industrial machinery or equipment, and areas where residuals from using, storing or cleaning industrial machinery or equipment remain.

Scrap or store old equipment in trailers due to concern over oil, grease, hydraulic fluid, or other residues being exposed.  No washing or cleaning anything outside, including fleet vehicles.  Any visible stains are disqualifiers and need to be removed as much as possible.


2. Materials or residuals on the ground or in storm water inlets from spills/leaks.

As above, there cannot be any visible staining or materials. Inspect the property, including every catch basin and inlet, and clean, coat or repave as needed.   Watch for combined drainage systems and concerns that could be from an adjacent property/facility.


3. Materials or products from past industrial activity.

Make sure historical issues or releases have been fully remediated—issues left by the previous owner can still disqualify your facility in the present.


4. Material handling equipment (except adequately maintained vehicles).

Fork trucks can be stored outdoors, as long as they are up-to-date in terms of maintenance and are clean. Focus on preventing the inadvertent carrying of material from inside the facility outside on vehicle wheels and in beds.


5. Materials or products during loading/unloading or transporting activities.

Ideally, hose connections for transfers should take place within an enclosure. Make sure bulk chemical unloading is free from drips or leaks.


6. Materials or products stored outdoors (except for final products intended for outside use [e.g., new cars] where exposure to storm water does not result in the discharge of pollutants).

There are very few exceptions here, although some do exist.


7. Materials contained in open, deteriorated or leaking storage drums, barrels, tanks, and similar containers.

Protection from precipitation is not required for drums, barrels, tanks, and similar containers that are tightly sealed, provided those containers are not deteriorated, do not leak, are banded or otherwise secured, and do not have operational taps or valves.   They must also be clean and free of any residues.


8. Materials or products handled/stored on roads or railways owned or maintained by the discharger.

Again, products cannot be exposed during handling or storage as part of shipping/distribution.


9. Waste material (except waste in covered, non-leaking containers [e.g., dumpsters]).

Keep dumpster lids closed and use canopies wherever possible for roll-offs.  Tarps are difficult to keep in place consistently, so require that your waste haulers provide alternatives.  Replace roll-offs if possible with smaller dumpsters with lids.


10. Application or disposal of process wastewater (unless otherwise permitted).

This includes cooling water, condensate, blowdown, etc.   Condensate pipes typically cause oil staining on pavement and should be directed into a suitable sealed container.


11. Particulate matter or visible deposits of residuals from roof stacks and/or vents not otherwise regulated (i.e., under an air quality control permit) and evident in the storm water outflow.

Inspect roof areas routinely for deposits. Ensure that dust collectors are emptied regularly and roof areas and vents are clean.


Keep in mind that it is typically worth attempting to qualify for this exclusion, because the permitting process will still require you to identify these areas of concern and address them through Best Management Practices (BMPs).    It will be much more cost-effective, to address any concerns proactively and avoid the permitting process if possible. 

If it is not possible for your facility to qualify for the No Exposure Exclusion, be sure to check back for our fourth and final article in this series for a discussion of common findings during storm water enforcement inspections and helpful suggestions for improving your compliance.

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