On February 23, 2011, following ten years of litigation, the U.S. Environmental Protection Agency (“EPA”) released scaled-back air emission rules for industrial boilers and solid waste incinerators. EPA received over 4,800 public comments after it released proposed boiler and incinerator rules in April 2010, and EPA estimates that the cost to industry to implement the scaled-back rules will be approximately $1.8 billion - half the estimated $3.6 billion cost of complying with the originally proposed rules.

The recently released final rules address hazardous air pollutant (“HAP”) emission standards for industrial, commercial and institutional boilers and process heaters (the Boiler Maximum Achievable Control Techcnology or "Boiler MACT" rule) and commercial and industrial solid waste incineration units (the “CISWI” rule). Industrial boilers and process heaters burn fuels such as natural gas, biomass, coal and oil to produce heat or electricity; CISWIs burn solid waste.

EPA issued the final rules after a federal district court last month denied EPA’s request to further postpone their issuance for an additional fifteen months, and instead extended the court-imposed deadline (originally set at December 15, 2007 and subsequently extended multiple times) for one month – to February 21, 2011. The final Boiler MACT rule affects numerous industries, including paper mills, refineries, and chemical and manufacturing plants.

The Boiler MACT rules create emission limits for mercury, particulate matter and carbon monoxide for all new coal-fired boilers with heat input greater than 10 million Btu per hour and particulate matter emission limits for new biomass and oil-fired boilers. New boilers with heat input below 10 million Btu per hour will be required to undergo a boiler tune-up every two years. For existing boilers, the new rules create emission limits for mercury and carbon monoxide only for coal-fired boilers with input greater than 10 million Btu per hour. EPA did not establish emission limits for other existing boilers. Instead, those boilers must undergo a tune-up every two years.

Industrial boilers at major sources (those facilities that emit ten or more tons per year of a single air toxic or twenty-five or more tons per year of any combination of air toxics) are subject to emission limits for five different HAPs: mercury, dioxin, particulate matter, hydrogen chloride and carbon monoxide. The only exceptions for major source boilers are for natural gas and other “clean fuel” burning boilers and those boilers with heat input capacity below 10 million Btu per hour.

The new CISWI rule sets New Source Performance Standards and emission guidelines for 88 specific commercial and industrial solid waste incineration units. The CISWI rule establishes emission limits for mercury, lead, cadmium, hydrogen chloride, particulate matter, carbon monoxide, dioxin/furans, nitrogen oxides and sulfur dioxide. The affected incinerator units must come into compliance with the new limits by February 2016, at the latest. 

The fate of this latest final rule package is uncertain, considering EPA expressed doubt that itcould issue defensible boiler and incinerator rules when it sought an additional fifteen month extension from the federal district court. However, EPA announced that it intends to begin the formal process of reconsidering these final rules, with additional details of the reconsideration process to be released in the near future.