EPA’s final combustion air rules for boilers and incinerators were issued on December 21. They include national emission standards for hazardous air pollutants for “major” source boilers and for “area” source boilers, new source performance standards for commercial and industrial solid waste incinerators (“CISWI”), and a Resource Conservation and Recovery Act (“RCRA”) non-hazardous secondary materials (“NHSM”) rule to assist in determining whether facilities are subject to the boiler MACT or the stricter CISWI rules based on the material burned in the units.
The combustion rules were first issued in April 2011, but EPA self-initiated a stay and review of the rules to address industry concerns that compliance with the rules would be impossible. The final rules addressed some of those concerns by removing strict numeric limits on dioxins and furans and replacing them with work practice standards, and by allowing boilers burning natural gas and other “clean” gases to comply by meeting work practice standards. The RCRA rule expanded the materials that qualify as fuels, including scrap tires, and created a process under which EPA can deem a material a “non-waste fuel.” The rules also delayed the compliance date for major and area source boilers until March 21, 2014, and delayed compliance with the CISWI rule from 2016 to 2018. States can grant an additional year of delay in compliance on a case-by-case basis.
The CISWI rule scaled back emission limits for a number of pollutants for incinerators built between 2000 and 2010, including carbon monoxide, acid gases, nitrogen oxides and sulfur dioxide, and scaled back limits for carbon monoxide and lead for new incinerators (and strengthened limits for acid gases). Limits for energy recovery units were also scaled back, including carbon monoxide, lead and mercury limits for biomass and coal-burning units in the category.