Industrial Storm Water Runoff

Q: The other day during our annual inspection by the sewer district, they expressed concern over our "boneyard" behind the plant where we store used equipment, tanks, and scrap building materials, mainly metals. While the area is not under their authority, they said they're working with the city's public works department to identify potential sources of industrial storm water discharges into the city's storm sewer system as they conduct their normal inspections. The inspectors then finished their typical tour and review of our records without saying anything more about this issue. Needless to say, we are concerned that they will report us to the public works department and we'll be inspected by them. This is the first time we have heard anything about the city's concern regarding our storm water.

Do you have any input to help us prepare for what will surely be a future inspection? D.Q.

A: If your storm water does not discharge to a combined (sanitary and storm) sewer system (which it apparently does not, since you have been informed that your storm water discharges to a storm sewer), you are covered by U.S. EPA and your state's storm water regulations. Back in 1990, U.S. EPA issued its Phase 1 storm water regulations (40CFR122) that not only impacted industrial facilities like yours, but also large and medium-size cities and certain counties that own and operate storm water sewer systems (aka municipal storm sewer systems, MS4s). In 1999, EPA finalized its Phase 2 storm water regulations, which brought under regulation "small" cities in urbanized areas as well as selected small cities and created a "no exposure" certification option for "light industrial" facilities, which covers basically all plating and metal finishing facilities.

Each MS4 has been issued a permit either by EPA or its respective state to cover the discharge(s) from its storm sewer system(s). This permit requires the MS4, or the city in your case, to develop and implement a storm water management system to reduce contamination of storm water runoff and prohibit "illicit" discharges-unpermitted or illegal non-storm water discharges such as non-contact cooling water, cooling tower water blowdown, boiler blowdown, process wastewaters, and sanitary wastewaters-from flowing into the storm sewer system.

These regulations give you basically two choices: either apply for and comply with an industrial storm water NPDES permit for the direct discharge of industrial storm water to surface waters, or qualify for and submit a "no exposure" certification. Our recommendation is that if "no exposure" is feasible, its certification is to be pursued.

Facilities interested in the "no exposure" certification exclusion must be able to certify "...that there are no discharges of storm water contaminated by exposure to industrial activities or materials from the industrial facility or site..." and that "...all industrial materials and activities are protected by a storm resistant shelter to prevent exposure to rain, snow, snowmelt, and/or runoff." Exceptions to these requirements include containers (such as drums, barrels, and tanks) that are sealed, clean, not deteriorated, and not leaking; adequately maintained vehicles used in material handling; final products, other than products that would be mobilized in storm water discharges.

The no exposure certification contains eleven questions regarding your facility; a "No" response is required to ALL questions in order to qualify for the exclusion. Specific to the issue raised by your sewer district because of your "boneyard," one of the 11 questions is "using, storing, or cleaning industrial machinery or equipment, and areas where residuals from using, storing, or cleaning industrial machinery or equipment remain and are exposed to storm water." Based upon U.S. EPA guidance on this issue, you basically have three choices: 1) clean up and remove the equipment and any residuals; 2) if storage of equipment is temporary, remove residuals and cover the equipment with well secured, storm resistant covers; or 3) if storage of equipment is permanent, remove residuals and store equipment under a permanent shelter or canopy or store equipment inside. The bottom line is that storm water cannot contact the stored equipment or any of its residuals. You can review USEPA's "no exposure" certification form at www.epa.gov/npdes/pubs/msgp2008_appendixk.pdf.

All but five states have authority over this industrial storm water program and the certification form is to be submitted to your state EPA. Based upon our experience, almost every state utilizes the U.S. EPA form, although we recommend that you check with your state EPA to verify. Because of the comprehensive language contained in the "no exposure" certification and its liability, it is imperative that you closely evaluate your facility for eligibility. As described above, significant changes in outside material, waste, and equipment handling and storage may be necessary to address exclusion requirements.

While the exclusion certification must be submitted every five years, we recommend that you evaluate your facility annually to verify ongoing compliance.

If you are unable to certify for "no exposure," you are required to apply for an industrial storm water discharge permit. There are two options for permitting: an individual permit customized for your facility or a general permit. For the vast majority of light industrial facilities, both U.S. EPA and states with control authority have what is called a "multi-sector" general permit that is not too overly burdensome (the exception may be California). If you find that you need to be permitted, this is our recommended direction.

The heart of this general permit is a Storm Water Pollution Prevention Plan (SW3P) that must spell out the Best Management Practices that you have implemented and/or will implement to eliminate or reduce storm water contact with your industrial activities. The SW3P will also include periodic inspections, training and periodic visual monitoring of your storm water outfalls. Also, some states do require sampling, analysis, and reporting.

Finally, some MS4s have additional requirements for permitted facilities. You can review your state's industrial storm water permit by going to their Web site. Application for a general permit is quite simple; usually, the application is 2-3 pages.

For more information regarding USEPA's industrial storm water regulations, you can visit http://cfpub.epa.gov/npdes/stormwater/indust.cfm.