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Thursday, August 11, 2011

EPA’s Boiler MACT: Controlling Emissions of Hazardous Air Pollutants

James E. McCarthy
Specialist in Environmental Policy

On May 16, 2011, the U.S. Environmental Protection Agency (EPA) announced that it was delaying the effective date of new Maximum Achievable Control Technology standards for boilers (the “Boiler MACT”), in order to take additional public comment and complete reconsideration of the rule. The standards were promulgated February 21, 2011, to meet the requirements of Section 112 of the Clean Air Act. There is widespread interest in the rule’s requirements and their potential effects, because boilers are used as power sources throughout industry, and for power or heat by large commercial establishments and institutions as well.

EPA developed the regulations because it has found, based on emissions data, that boilers (including coal-, biomass-, and liquid-fired boilers) are major sources of hazardous air pollutants (HAPs). The Clean Air Act defines a major source as any facility that emits 10 tons or more of a single listed HAP or 25 tons of any combination of HAPs annually. The HAPs themselves (187 substances) were listed by Congress in the 1990 Clean Air Act Amendments.

The rule promulgated in February would replace a 2004 version of the rule that was vacated and remanded to EPA by the D.C. Circuit Court of Appeals. EPA was under a court order to promulgate a replacement by January 2011. In early December 2010, the agency asked that the promulgation deadline be postponed to April 2012 so that it could revise the proposed rule based on new information it had received. The court refused EPA’s request, but did grant it five extra weeks. In order to obtain the time it wanted, EPA announced on the same day that it promulgated the rule that it would reconsider it. The agency subsequently asked for comment on 14 different aspects of the rule, and stated that it will propose any changes to the rule by October, and make final decisions by April 2012.

As promulgated in February, the MACT would affect 13,840 boilers and process heaters, with capital costs of $5.1 billion, according to the agency; annualized costs, which spread the costs of capital over the expected life of the equipment and include operating and maintenance expenses, were estimated at $1.4 billion per year. Most of these costs would be borne by boilers that burn coal, biomass, or liquid fuels, which together account for only 12.7% of all the units covered by the rule. Most (83%) of the boilers affected by the rule are fueled by natural gas or refinery gases. These boilers would not have to install pollution control equipment and would experience cost savings under the rule, according to EPA. For the rule as a whole, EPA estimated that benefits— including the avoidance of 2,500 to 6,500 premature deaths annually—would outweigh costs by at least $20 billion per year.

Affected industries and many in Congress have raised objections to the rule both as proposed and as promulgated, and bills have been introduced in both the House and Senate (H.R. 2250 and S. 1392) to alter the rule’s requirements and delay its implementation. In response to comments, the rule promulgated in February 2011 had already reduced the number of units expected to require controls, and made the emissions standards much less stringent than those in the proposed rule, reducing the agency’s estimate of annualized control costs from $2.9 billion to $1.4 billion.

This report also discusses three related rules that EPA promulgated at the same time as the Boiler MACT, dealing with smaller “area source” boilers and with commercial and industrial boilers that burn solid waste (the “CISWI rule”). These rules have been less controversial, but the CISWI rule is also being stayed to allow its reconsideration.

Date of Report: August 4, 2011
Number of Pages: 26
Order Number: R41459
Price: $29.95

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