The Environmental Protection Agency has issued a letter explaining the effects of the December DC Circuit Court decision that vacated two provisions of 40 CFR Part 63.6, the general provisions section of the National Emission Standards for Hazardous Air Pollutants. Parts 63.6(f)(1) and 63.6(h)(1) exempted sources from requirements to meet applicable emission standards during periods of startup, shutdown or malfunction.
The exemptions remain in effect until the Court issues a mandate finalizing the vacature. At that time, the EPA letter notes, the effects of the rule change will vary among regulated emission sources. For instance, sources required to demonstrate compliance using only work practice standards should have no difficulty complying, while other sources may operate pollution control equipment that is not impacted by SSM events. For sources that fail to comply with emission standards during SSM events, EPA indicated that it will determine its enforcement response based on factors such as “good faith efforts” and whether a malfunction event may have been “caused in part by poor maintenance or careless operation.”
The text of the EPA letter and other information concerning the Court’s decision and its effects can be found at http://www.epa.gov/compliance/civil/caa/ssm.html.