May 3, 2010Client Alert

Boiler MACT/ CISWI Rules, Take III

On April 29, 2010, the U.S. Environmental Protection Agency (“EPA”) published proposed rules relating to hazardous air pollutant (“HAP”) emission standards for industrial, commercial and institutional boilers, process heaters – the 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, coal and oil to produce heat or electricity; CISWIs burn solid waste. The proposed rules come with much anticipation and after years of uncertainty for affected industries, including paper mills, refineries, and chemical and manufacturing plants.

Section 112 of the Clean Air Act (“CAA”) requires EPA to set emission standards for categories of major sources of HAPs. Major sources are those facilities that emit or have the potential to emit 10 tons per year of a single HAP or 25 tons per year of total HAPs. The 1990 CAA Amendments required those standards to be based on the Maximum Achievable Control Technology (“MACT”). EPA first finalized a set of Boiler MACT and CISWI rules in September 2004; a petition for review of those rules was filed in November 2004. In 2005, EPA reconsidered the rule package, modified a portion, and again published a final rule package. In early 2006, another petition for review was filed, and in June 2007, the D.C. Circuit Court of Appeals vacated the Boiler MACT and CISWI rules and ordered EPA to revise the rules consistent with its duties pursuant to the CAA.

The new proposed Boiler MACT rules set HAP standards for industrial, commercial and institutional boilers and process heaters at major source facilities. The proposed Boiler MACT rule is expected to reduce mercury and other organic air toxics, including dioxin emissions. The proposed rule package also includes HAP standards for boilers and process heaters at “area sources” – also known as “minor sources”; area source facilities may subject to MACT or Generally Available Control Technology (“GACT”).

The proposed CISWI rule sets New Source Performance Standards and emission guidelines for commercial and industrial solid waste incineration units. The proposed CISWI rule establishes emission limits for mercury, lead, cadmium, hydrogen chloride, particulate matter, carbon monoxide, dioxin/furans, nitrogen oxides and sulfur dioxide.

To determine whether a major source will be subject to the Boiler MACT rule or the CISWI rule, EPA has also proposed a definition of “non-hazardous solid waste.” EPA fact sheets indicate the proposed definition could move some facilities out of the “boiler” category and into the CISWI category.

EPA estimates the proposed rules will reduce mercury emissions from affected facilities by more than 50%, but that it will cost industry approximately $3.6 billion annually to install and operate pollution controls necessary to comply with the proposed rules. EPA also estimates the proposed rules will result in “health benefits” estimated at $18 - $44 billion annually and, according to the agency, the costs to comply are significantly outweighed by the public health benefits. EPA will accept public comments on the proposed rules for 45 days after they are published in the Federal Register.

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