As April's showers become May's flowers, warmer weather inspires facilities to clean HVAC equipment more frequently. In my audits, I often find that rinsate from these cleaning activities is discharged to storm drains or swales - even though such non-stormwater discharge is often specifically prohibited in stormwater permits and by state or local stormwater regulations. Because stormwater rules typically apply to all persons, not just to permitted operations, these regulations probably apply to your facility whether you have permits or not.

For example, Cincinnati, OH prohibits any pollutant or water containing pollutants to be discharged to the stormwater system (Code of Ordinances, Title VII, Section 720-44, "Prohibition of Illicit Discharges and Connections"). The list of exempted and allowable non-stormwater sources includes water line flushing, landscape irrigation, air conditioning condensation, and discharges or flows from firefighting activities-not rinsate from building or equipment cleaning, whether detergents or coil cleaning chemicals are used or not. Some jurisdictions even prohibit discharge of washwaters to the pavement or ground. Knoxville, TNprohibits such "discharge to the stormwater system, or any component thereof, or onto driveways, sidewalks, parking lots, sinkholes, creek banks, or other areas draining to the stormwater system" (Code of Ordinances, Sec. 22.5-52). The city also prohibits the use of algae inhibitors in HVAC condensate drain pans.

As HVAC rinsate discharges receive more scrutinty and communities with Municipal Separate Storm Sewer Systems (MS4s) increase enforcement activities, a few jurisdictions are developing new regulations specifically for HVAC rinsate. Certain jurisdictions would allow some discharges of rinsate if detergents were not used during maintenance and cleaning. Others propose licensing for companies that provide HVAC equipment cleaning services and other so-called "cosmetic cleaning" like window washing. The proposed licensing process reminds and binds the operators to perform minimal treatment, such as separation of solids, prior to discharging the rinsate. To the best of my knowledge, however, none of those rules have yet been finalized.

So what can you do? First, review your state and local/municipal stormwater regulations to find out what you may and may not discharge. If discharges of water from equipment cleaning are prohibited, consider routing the rinsate to your sanitary sewer. Your local POTW may allow you to discharge the rinsate, although you may need to obtain or revise a permit. If your facility has an individual NPDES permit and a wastewater treatment system, that system may be able to handle the rinsate. Finally, if routing the discharge to the sanitary sewer is infeasible or prohibited by your POTW, then you must work with your service provider to collect the rinsate and send it offsite for treatment or disposal.

Barbara Jo Ruble, QEP, CPEA is the President of Specialty Technical Consultants. She has more than 30 years of experience helping clients in a wide variety of industries to develop, assess, and improve their EHS management systems and compliance programs. Barb has performed more than 200 EHS compliance audits or management systems assessments of industrial facilities worldwide. She has also provided independent review of corporate EHS auditing programs. Barb is the primary author of OHSAS 18001/OSHA-VPP Occupational Health & Safety Management Systems: A Complete Implementation Guide, published by Specialty Technical Publishers of Vancouver, Canada.

For more information about STC's EHS auditing services or to discuss this article, contact Barb at bruble@stcenv.com or at 410-625-1952.