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Proposed Rule

Approval and Promulgation of Air Quality Implementation Plans; Pennsylvania; Control of Particulate Matter Emissions From the Operation of Outdoor Wood-Fired Boilers

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Environmental Protection Agency (EPA).


Proposed rule.


EPA is proposing to approve a State Implementation Plan (SIP) revision submitted by the Commonwealth of Pennsylvania. This revision pertains to the control of particular matter emissions from the operation of outdoor wood-fired boilers. This action is being taken under the Clean Air Act (CAA).


Written comments must be received on or before August 15, 2011.


Submit your comments, identified by Docket ID Number EPA-R03-OAR-2011-0288 by one of the following methods

A. Follow the on-line instructions for submitting comments.

B. E-mail:

C. Mail: EPA-R03-OAR-2011-0288, Cristina Fernandez, Associate Director, Office of Air Program Planning, Mailcode 3AP30, U.S. Environmental Protection Agency, Region III, 1650 Arch Street, Philadelphia, Pennsylvania 19103.

D. Hand Delivery: At the previously-listed EPA Region III address. Such deliveries are only accepted during the Docket's normal hours of operation, and special arrangements should be made for deliveries of boxed information.

Instructions: Direct your comments to Docket ID No. EPA-R03-OAR-2011-0288. EPA's policy is that all comments received will be included in the public docket without change, and may be made available online at, including any personal information provided, unless the comment includes information claimed to be Confidential Business Information (CBI) or other information whose disclosure is restricted by statute. Do not submit information that you consider to be CBI or otherwise protected through or e-mail. The Web site is an “anonymous access” system, which means EPA will not know your identity or contact information unless you provide it in the body of your comment. If you send an e-mail comment directly to EPA without going through, your e-mail address will be automatically captured and included as part of the comment that is placed in the public docket and made available on the Internet. If you submit an electronic comment, EPA recommends that you include your name and other contact information in the body of your comment and with any disk or CD-ROM you submit. If EPA cannot read your comment due to technical difficulties and cannot contact you for clarification, EPA may not be able to consider your comment. Electronic files should avoid the use of special characters, any form of encryption, and be free of any defects or viruses.

Docket: All documents in the electronic docket are listed in the index. Although listed in the index, some information is not publicly available, i.e., CBI or other information whose disclosure is restricted by statute. Start Printed Page 41743Certain other material, such as copyrighted material, is not placed on the Internet and will be publicly available only in hard copy form. Publicly available docket materials are available either electronically in or in hard copy during normal business hours at the Air Protection Division, U.S. Environmental Protection Agency, Region III, 1650 Arch Street, Philadelphia, Pennsylvania 19103. Copies of the State submittal are available at the Pennsylvania Department of Environmental Protection, Bureau of Air Quality Control, P.O. Box 8468, 400 Market Street, Harrisburg, Pennsylvania 17105.

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Rose Quinto, (215) 814-2182, or by e-mail at

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On October 20, 2010, the Pennsylvania Department of Environmental Protection (PADEP) submitted a revision to its SIP for the control of particular matter (PM) emissions from the operation of outdoor wood-fired boilers (OWBs).

I. Background

On July 18, 1997 (62 FR 38652), EPA amended the National Ambient Air Quality Standard (NAAQS) for PM to add a new standard for fine particles, using fine particulates equal to or less than 2.5 micrometers in diameter (PM2.5) as the indicator. EPA set the health-based (primary) and welfare-based (secondary) PM2.5 annual standard at a level of 15 micrograms per cubic meter (μg/m3) and the 24-hour standard at a level of 65 μg/m3. The health-based primary standard is designed to protect human health from elevated levels of PM2.5, which have been linked to premature mortality and other health effects. The secondary standard is designed to protect against major environmental effects of PM2.5 such as visibility impairments, soiling, and materials damage. On October 17, 2006 (71 FR 61236), EPA revised the primary and secondary 24-hour NAAQS for PM2.5 to 35 μg/m3 from 65 μg/m3.

A significant and growing source of PM2.5 emissions in the Commonwealth of Pennsylvania is from OWBs. OWBs, also referred to as outdoor wood-fired furnaces, outdoor wood-burning appliances, or outdoor hydronic heaters, are free-standing fuel burning devices designed: (1) To burn clean wood or other approved solid fuels; (2) specifically for outdoor installation or installation in structures not normally intended for habitation by humans or domestic animals, such as garages; and (3) to heat building space or water by means of distribution, typically through pipes, of a fluid heated in the device, typically water or a water and antifreeze mixture. They resemble a small shed or mini-barn with a short smokestack on top. OWBs are being sold to heat homes and buildings; produce domestic hot water; heat swimming pools or hot tubs; and provide heat to agricultural operations such as greenhouses and dairies.

A concern associated with certain OWBs is the air pollution they may produce. Smoldering fires and short smokestacks may create heavy smoke to the ground that sometimes causes a neighborhood nuisance or an adverse impact on public health and the environment. Smoke from OWBs which forms from incomplete combustion, contains emissions from fine particle pollution, carbon monoxide, and other organic products, such as formaldehyde, benzene and aromatic hydrocarbons, all of which can cause cancer. When inhaled, fine particles from smoke emissions are carried deep into the lungs and can impair lung function and aggrevate existing medical conditions such as asthma, lung, or heart disease. Individuals particularly sensitive to PM2.5 exposure include older adults, people with lung and heart disease, and children.

Unlike indoor wood stoves that are regulated by EPA, OWBs are not required to meet a Federal emission standard, and the majority of them are not equipped with pollution controls. EPA initiated a voluntary program that encourages manufacturers of OWBs to improve air quality through developing and distributing cleaner-burning, more efficient OWBs. Through this voluntary effort, OWBs are certified and labeled to meet EPA emissions performance levels in two phases. Phase 1 of the program was in place from January 2007 through October 15, 2008. To qualify for Phase 1, manufacturers were required to develop an OWB model that was 70 percent cleaner-burning than unqualified models by meeting the EPA air emission standard of 0.6 pound PM per million British thermal unit (Btu) heat input as tested by an independent accredited laboratory. Phase 1 OWB models are labeled with an orange tag. Phase 1 Partnership Agreements ended when Phase 2 Partnership Agreements were initiated on October 16, 2008. To qualify for Phase 2, manufacturers must develop an OWB model that is 90 percent cleaner-burning than the Phase 1 OWBs and meet the EPA air emissions standard of 0.32 pound PM per million Btu heat output. The Phase 2 OWB models, just like the Phase 1 OWB models are also tested by an independent accredited laboratory. Phase 2 OWB models are labeled with a white tag. Additional information about the EPA voluntary OWB program is available on EPA's Web site at​burnwise. Furthermore, the Northeast States for Coordinated Air Use Management (NESCAUM), which is a regional air pollution control organization, comprised of the air program directors of all the New England states, New York and New Jersey, in coordination with a number of states and EPA, developed a model rule for regulating OWBs (also known as outdoor hydronic heaters (OHHs)). The model rule was released in January 2007 and is available at​topics/​outdoor-hydronic-heaters. The purpose of the model rule is to assist state and local agencies in adopting requirements that will reduce air pollution from OWBs. The model rule establishes emission limits and labeling requirements for new OWBs and contains the following components for both new and existing OWBs: setback requirements from property lines, structures, and homes; stack height requirements; and distributor and buyer notification requirements.

II. Summary of SIP Revision

The SIP revision adds definitions and terms to Title 25 of the Pennsylvania Code (25 Pa. Code) Chapter 121.1, relating to definitions, used in the substantive provision of this SIP revision. In addition, the SIP revision adds a new regulation to 25 Pa. Code Chapter 123 (Standards for Contaminants) Particulate Matter Emissions, Section 123.14 (Outdoor Wood-Fired Boilers). The emission standard established in this SIP revision is the Phase 2 emission standard described in the EPA voluntary OWB program. The SIP revision is also based on the NESCAUM model rule.

The new regulation (Section 123.14) applies to the following: (1) To a person, manufacturer, supplier or distributor who sells, offers for sale, leases or distributes an outdoor wood-fired boiler for use; (2) a person who installs an outdoor wood-fired boiler; and (3) a person who purchases, receives, leases, owns, uses or operate an outdoor wood-fired boiler. The new regulation consists of the following: (1) Exemptions for a non-Phase 2 OWB; (2) Phase 2 OWB provisions; (3) setback requirements for new Phase 2 OWBs; (4) stack height requirements for new Phase 2 OWBs; (5) allowed fuels; (6) prohibited fuels; and (7) applicable laws and regulatory requirements. A detailed summary of EPA's review of and rationale for Start Printed Page 41744proposing to approve this SIP revision may be found in the Technical Support Document (TSD) for this action which is available online at, Docket number EPA-R03-OAR-2011-0288.

III. Proposed Action

EPA is proposing to approve the Pennsylvania SIP revision that amends 25 Pa. Code Chapter 121.1 by adding new definitions, and adding a new regulation, 25 Pa. Code Chapter 123, Section 123.14, pertaining to the control of PM emissions from the operation of OWBs. This SIP revision was submitted on October 20, 2010. The emission standard established in this SIP revision is the Phase 2 emission standard described in the EPA voluntary program. This SIP revision is also based on the NESCAUM model rule that assisted PADEP in adopting requirements that will reduce air pollution from OWBs. This SIP revision reduces the problems associated with the operation of OWBs, including smoke, odors and burning prohibited fuels, including garbage, tires, and hazardous waste. Reductions in ambient levels of PM2.5 would promote improved human and animal health and welfare, improved visibility, decreased soiling and materials damage, and decrease damage to plants and trees. EPA is soliciting public comments on the issues discussed in this document. These comments will be considered before taking final action.

IV. Statutory and Executive Order Reviews

Under the CAA, the Administrator is required to approve a SIP submission that complies with the provisions of the CAA and applicable Federal regulations. 42 U.S.C. 7410(k); 40 CFR 52.02(a). Thus, in reviewing SIP submissions, EPA's role is to approve state choices, provided that they meet the criteria of the CAA. Accordingly, this action merely proposes to approve state law as meeting Federal requirements and does not impose additional requirements beyond those imposed by state law. For that reason, this proposed action:

  • Is not a “significant regulatory action” subject to review by the Office of Management and Budget under Executive Order 12866 (58 FR 51735, October 4, 1993);
  • Does not impose an information collection burden under the provisions of the Paperwork Reduction Act (44 U.S.C. 3501 et seq.);
  • Is certified as not having a significant economic impact on a substantial number of small entities under the Regulatory Flexibility Act (5 U.S.C. 601 et seq.);
  • Does not contain any unfunded mandate or significantly or uniquely affect small governments, as described in the Unfunded Mandates Reform Act of 1995 (Pub. L. 104-4);
  • Does not have Federalism implications as specified in Executive Order 13132 (64 FR 43255, August 10, 1999);
  • Is not an economically significant regulatory action based on health or safety risks subject to Executive Order 13045 (62 FR 19885, April 23, 1997);
  • Is not a significant regulatory action subject to Executive Order 13211 (66 FR 28355, May 22, 2001);
  • Is not subject to requirements of Section 12(d) of the National Technology Transfer and Advancement Act of 1995 (15 U.S.C. 272 note) because application of those requirements would be inconsistent with the CAA; and
  • Does not provide EPA with the discretionary authority to address, as appropriate, disproportionate human health or environmental effects, using practicable and legally permissible methods, under Executive Order 12898 (59 FR 7629, February 16, 1994).

In addition, this proposed rule, pertaining to Pennsylvania's control of PM emissions from the operation of outdoor wood-fired boilers, does not have tribal implications as specified by Executive Order 13175 (65 FR 67249, November 9, 2000), because the SIP is not approved to apply in Indian country located in the state, and EPA notes that it will not impose substantial direct costs on tribal governments or preempt tribal law.

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List of Subjects in 40 CFR Part 52

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Authority: 42 U.S.C. 7401 et seq.

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Dated: June 28, 2011.

W.C. Early,

Acting Regional Administrator, Region III.

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[FR Doc. 2011-17866 Filed 7-14-11; 8:45 am]