New Permit Application Process for Major Air Pollution Sources with Boilers

Boilers and process heaters as major sources of hazardous air pollutants were subject to regulation under the Clean Air Act (CAA), National Emission Standards for Hazardous Air Pollutants (NESHAP), commonly known as the Boiler MACT (maximum achievable control technology). However, on July 31, 2007, EPA's Boiler MACT was vacated by the D.C. Circuit Court of Appeals. Now, many regulatory officials including EPA, feel that the absence of the Boiler MACT triggers the requirement of s. 112(j)(2) of the CAA which generally requires affected facilities to submit a permit application for a case-by case MACT determination. Under the 112(j) requirement, the latest date for submittal of an application would be 18 months after the Boiler MACT was vacated.

The Department of Natural Resources (DNR) is developing an application form for Wisconsin businesses affected by vacatur of the Boiler MACT. The form will be available in December 2008 to help sources demonstrate compliance with 112(j). The DNR will process these applications in accordance with EPA rules and any further guidance provided by the agency. The DNR strongly recommends that any major source of federal hazardous air pollutant (HAP) emissions that operates a boiler or process heater complete the application and submit it to the DNR Bureau of Air Management by January 27, 2009. This includes sources that only burn gaseous or liquid fuels that had no substantive requirements under the vacated EPA rule. A major source is one that has maximum theoretical HAP emissions, facility-wide, at least 10 tons per year for any individual HAP or 25 tons per year for all HAPs.

In the absence of current guidance from EPA, the National Association of Clean Air Agencies (NACAA) has collected data from its members and provided NACAA Model Permit Guidance. This guidance should provide some national consistency in the case-by-case MACT determinations for affected boilers. The data suggests in most cases the emission standards for case-by-case MACT will be significantly more stringent than the vacated EPA rule. Also, the "low-risk" or "health-based" alternative for hydrogen chloride and manganese emissions, which the courts have vacated in another MACT, is not available under the NACAA model permit guidance.

Because the NACAA model permit guidance is more stringent than what was included in the vacated rule, sources may want to cap HAP emissions to avoid a case-by-case MACT. Sources interested in capping their emissions should include with their 112(j) application, a request to limit facility-wide HAP emissions below 10 tons per year for any individual HAP and below 25 tons per year for all HAPs. Sources may also submit additional emissions data they would like DNR to consider during the case-by-case MACT determination process.

For more information on this topic, please contact Roger Fritz, DNR Bureau of Air Management, at 608-266-1201 or Roger.Fritz@wisconsin.gov.

-- Renee Bashel