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Proposed Rule

Approval and Promulgation of Air Quality Implementation Plans; Pennsylvania; Motor Vehicle Inspection and Maintenance Program-Revised Final Standards for the Acceleration Simulation Mode Exhaust Emissions Test

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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 SIP revision amends the Commonwealth's SIP-approved Enhanced Vehicle Emission Inspection Program (or I/M program) to implement final tailpipe test standards for the Acceleration Simulation Mode (ASM) tailpipe emissions test. This is being done through the substitution of revised ASM test standards in place of the previously SIP-approved final standards. Since this change affects only testing performed using the ASM tailpipe test method, only that portion of the I/M-subject vehicles in the five-county Philadelphia area that receive ASM tailpipe testing are affected by this action. This action is being taken under the Clean Air Act.


Written comments must be received on or before July 28, 2003.


Comments may be submitted either by mail or electronically. Written comments should be mailed to Makeba Morris, Chief, Air Quality Planning Branch, Mailcode 3AP21, U.S. Environmental Protection Agency, Region III, 1650 Arch Street, Philadelphia, Pennsylvania 19103. Electronic comments should be sent either to or to, which is an alternative method for submitting electronic comments to EPA. Follow the detailed instructions of the Supplementary Information section. Copies of the documents relevant to this action are available for public inspection during normal business hours at the Air Protection Division, U.S. Environmental Protection Agency, Region III, 1650 Arch Street, Philadelphia, Pennsylvania 19103; and 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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Brian Rehn, (215) 814-2176, or by e-mail at

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I. Background

On June 5, 2003, the Pennsylvania Department of Environmental Protection submitted a request that EPA parallel process the approval of a revision to its State Implementation Plan (SIP) to amend its SIP-approved enhanced inspection and maintenance (I/M) program. The revision consists of a change of the Commonwealth's I/M program regulation to implement a revised set of final pass/fail testing standards for those vehicles that undergo Acceleration Simulation Mode (ASM) tailpipe test method. The Commonwealth is replacing final ASM test standards previously adopted and SIP-approved with a set of revised final standards issued by EPA that are being adopted by Pennsylvania as a compliance alternative to the previous final ASM standards.

The ASM test is a test method used to measure tailpipe emissions from cars. In Pennsylvania, the test is performed only in five counties in the Philadelphia severe ozone nonattainment area (Bucks, Chester, Delaware, Montgomery, and Philadelphia Counties), and therefore only on a portion of the I/M-subject fleet. The ASM tailpipe Start Printed Page 38267emissions test employs tailpipe emissions sensing equipment that measures emissions while the vehicle is driven, under load, at a steady speed on a chassis dynamometer. An emissions gas analyzer measures tailpipe emissions for certain pollutants. Specifically, the result is a concentration measurement for each of three pollutants—expressed in units of parts per million (ppm) of pollutant of hydrocarbons and oxides of nitrogen, and percent concentration of carbon monoxide. The results for each pollutant are compared against a standard, or cutpoint, that represents the maximum allowable amount of each pollutant that may be emitted, and a pass or fail determination is made based upon comparison of the test result to the cutpoint. Repairs would then be required to failing vehicles in an attempt to reduce the measured tailpipe pollutants to within acceptable limits. The ASM testing cutpoints vary depending upon vehicle type (i.e., car or truck), model year of manufacture, and vehicle weight—to represent the different standards with which different types of vehicles were manufactured to comply. In general, older vehicles must comply with less stringent test standards than newer vehicles, and heavier vehicles comply with less stringent test standards than lighter vehicles.

At the inception of the enhanced I/M program, EPA allowed states to employ a less stringent set of interim, or phase-in, ASM cutpoints in order to make a pass/fail determination, eventually requiring the state to implement more stringent final ASM test cutpoints for the duration of the program.

During the period when states were conducting ASM testing using the phase-in cutpoints, several states raised concerns to EPA that application of the final ASM cutpoints could result in an overly high level of failures, potentially failing some cars that marginally fail or that should not fail the test (i.e., false failures). EPA investigated the matter using I/M program data provided by several states, and as a result, EPA developed and released an alternative final set of ASM cutpoints to address the problem via an August 16, 2002 memorandum entitled “Revised Final Cutpoints for ASM5015 and ASM 252” to EPA's Regional Air Division Directors from Gregory Green, Director of the Certification and Compliance Division of EPA's Office of Transportation and Air Quality. These alternative cutpoints can be used by states as an optional means to comply with Federal I/M requirements for ASM I/M testing final cutpoints.

The alternative EPA final cutpoints were developed using a methodology that adjusts emissions on the basis of engine displacement rather than vehicle test weight. To apply the alternative ASM cutpoints, the tested vehicle's engine displacement (in liter units) is multiplied by the concentration of the exhaust pollutant (hydrocarbon, carbon monoxide, or oxides of nitrogen, in units of either ppm HC or NOX or % CO). The resultant value (in units of liters displacement*concentration) is compared to an EPA-generated table of cutpoints. If the test result exceeds the allowable cutpoint for any tested pollutant, the vehicle fails the ASM test for that pollutant. If the test results are lower than the allowable cutpoints for all tested pollutants, then the vehicle passes the ASM test.

EPA's policy provides states who elect to use the recently released alternative final ASM cutpoints the same level of emissions benefits, or credits, that would have been achieved by use of the previously available final cutpoints. Therefore, Pennsylvania was not required to perform a new analysis to determine potential changes in emissions benefits, as claimed in a SIP or other plan, from an ASM-based I/M program using final ASM cutpoints.

II. Summary of SIP Revision

The SIP revision consists of amendments to Pennsylvania's enhanced I/M program regulation, codified in Title 67 of the Pennsylvania Code, Part I, Subpart A, Article VII, Chapter 177, Subchapter A. Specifically, Section 1 of Appendix A (which contains procedures, standards, equipment specifications, and quality control specifications for the enhanced I/M program) is being revised. Specifically, the regulatory change replaces the previously adopted final ASM cutpoints that are based upon vehicle weight with EPA's alternative final cutpoints that are based upon engine displacement (released by EPA in an August 16, 2002 memorandum).

Pennsylvania is also amending the deadline for implementation of final ASM test cutpoints in the five counties in Southeast Pennsylvania comprising the Philadelphia I/M program area. The Commonwealth's proposed SIP stipulates that the final cutpoints will apply upon notice by the Department of Transportation. However, the Commonwealth is under court order by the United States District Court for the Eastern District of Pennsylvania in the case of Clean Air Council v. Mallory and Seif, No. 01-179 to fully implement either the original or the alternative final ASM cutpoints by September 1, 2003. There are three compelling reasons for EPA to approve the proposed time frame for final ASM cutpoint implementation: (1) The SIP deadline that is being removed from the SIP has past and can no longer be met; (2) the Commonwealth is moving as expeditiously as possible to adopt the new EPA alternative ASM cutpoints; and (3) the Federal court order compels the Commonwealth to implement final cutpoints on an expedited schedule that is as ambitious as can reasonably be expected. Therefore, EPA believes that the Commonwealth's SIP revision, in conjunction with a Federal court order, will provide for implementation of final ASM cutpoints by September 1, 2003.

Specific details of the final cutpoints being adopted by Pennsylvania are available for review in the technical support document (TSD) prepared by EPA for this action and in the proposed SIP materials submitted by Pennsylvania, both of which are contained in the docket for this rulemaking action. These materials are available for inspection at the locations listed in the ADDRESSES section of this rulemaking action. A copy of the TSD is also available, upon request, by contacting Brian Rehn at (215) 814-2176, or by e-mail at

III. Proposed Action

EPA proposing to approve Pennsylvania's SIP revision for ASM test standards under the enhanced I/M program in Southeast Pennsylvania, which was submitted on June 5, 2003. EPA is soliciting public comments on the issues discussed in this notice or on other relevant matters. These comments will be considered before taking final action. Interested parties may participate in the Federal rulemaking procedure by submitting either electronic or written comments. To ensure proper receipt by EPA, identify the appropriate rulemaking identification number [writer: insert AIRTRAX No.] in the subject line on the first page of your comment. Please ensure that your comments are submitted within the specified comment period. Comments received after the close of the comment period will be marked “late.” EPA is not required to consider these late comments.

1. Electronically. If you submit an electronic comment as prescribed below, EPA recommends that you include your name, mailing address, and an e-mail address or other contact information in the body of your comment. Also include this contact information on the outside of any disk or CD ROM you submit, and in any Start Printed Page 38268cover letter accompanying the disk or CD ROM. This ensures that you can be identified as the submitter of the comment and allows EPA to contact you in case EPA cannot read your comment due to technical difficulties or needs further information on the substance of your comment. EPA's policy is that EPA will not edit your comment, and any identifying or contact information provided in the body of a comment will be included as part of the comment that is placed in the official public docket, and made available in EPA's electronic public docket. 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.

i. E-mail. Comments may be sent by electronic mail (e-mail) to:, attention: [writer: insert AIRTRAX No.]. EPA's e-mail system is not an “anonymous access” system. If you send an e-mail comment directly without going through, EPA's e-mail system automatically captures your e-mail address. E-mail addresses that are automatically captured by EPA's e-mail system are included as part of the comment that is placed in the official public docket, and made available in EPA's electronic public docket.

ii. Your use of is an alternative method of submitting electronic comments to EPA. Go directly to at, then select “Environmental Protection Agency” at the top of the page and use the “go” button. The list of current EPA actions available for comment will be listed. Please follow the online instructions for submitting comments. The system is an “anonymous access” system, which means EPA will not know your identity, e-mail address, or other contact information unless you provide it in the body of your comment.

iii. Disk or CD ROM. You may submit comments on a disk or CD ROM that you mail to the mailing address identified in the ADDRESSES section of this document. These electronic submissions will be accepted in WordPerfect, Word or ASCII file format. Avoid the use of special characters and any form of encryption.

2. By Mail. Written comments should be addressed to the EPA Regional office listed in the ADDRESSES section of this document.

This revision is being proposed under a procedure called parallel processing, whereby EPA proposes rulemaking action concurrently with the state's procedures for amending its regulations. If the proposed revision is substantially changed in areas other than those identified in this document, EPA will evaluate those changes and may publish another notice of proposed rulemaking. If no substantial changes are made other than those areas cited in this document, EPA will publish a Final Rulemaking Notice on the revisions. The final rulemaking action by EPA will occur only after the SIP revision has been adopted by Pennsylvania and submitted formally to EPA for incorporation into the SIP.

IV. Statutory and Executive Order Reviews

Under Executive Order 12866 (58 FR 51735, October 4, 1993), this proposed action is not a “significant regulatory action” and therefore is not subject to review by the Office of Management and Budget. For this reason, this action is also not subject to Executive Order 13211, “Actions Concerning Regulations That Significantly Affect Energy Supply, Distribution, or Use” (66 FR 28355, May 22, 2001). This proposed action merely proposes to approve state law as meeting Federal requirements and imposes no additional requirements beyond those imposed by state law. Accordingly, the Administrator certifies that this proposed rule will not have a significant economic impact on a substantial number of small entities under the Regulatory Flexibility Act (5 U.S.C. 601 et seq.). Because this rule proposes to approve pre-existing requirements under state law and does not impose any additional enforceable duty beyond that required by state law, it 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). This proposed rule also does not have tribal implications because it will not have a substantial direct effect on one or more Indian tribes, on the relationship between the Federal Government and Indian tribes, or on the distribution of power and responsibilities between the Federal Government and Indian tribes, as specified by Executive Order 13175 (65 FR 67249, November 9, 2000). This action also does not have Federalism implications because it does not have substantial direct effects on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among the various levels of government, as specified in Executive Order 13132 (64 FR 43255, August 10, 1999). This action merely proposes to approve a state rule implementing a Federal standard, and does not alter the relationship or the distribution of power and responsibilities established in the Clean Air Act. This proposed rule also is not subject to Executive Order 13045 “Protection of Children from Environmental Health Risks and Safety Risks” (62 FR 19885, April 23, 1997), because it is not economically significant.

In reviewing SIP submissions, EPA's role is to approve state choices, provided that they meet the criteria of the Clean Air Act. In this context, in the absence of a prior existing requirement for the State to use voluntary consensus standards (VCS), EPA has no authority to disapprove a SIP submission for failure to use VCS. It would thus be inconsistent with applicable law for EPA, when it reviews a SIP submission, to use VCS in place of a SIP submission that otherwise satisfies the provisions of the Clean Air Act. Thus, the requirements of section 12(d) of the National Technology Transfer and Advancement Act of 1995 (15 U.S.C. 272 note) do not apply. This proposed rule to approve amendments to the ASM testing provisions of Pennsylvania's I/M program does not impose an information collection burden under the provisions of the Paperwork Reduction Act of 1995 (44 U.S.C. 3501 et seq.).

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List of Subjects in 40 CFR Part 52

  • Environmental protection
  • Air pollution control
  • Carbon monoxide
  • Intergovernmental relations
  • Nitrogen dioxide
  • Ozone
  • Reporting and recordkeeping requirements
  • Volatile organic compounds
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Authority: 42 U.S.C. 7401 et seq.

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Dated: June 17, 2003.

Richard J. Kampf,

Acting Regional Administrator, Region III.

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[FR Doc. 03-16237 Filed 6-26-03; 8:45 am]