Air Pollution:

Unresolved Issues May Hamper Success of EPA's Proposed Emissions Program

RCED-92-288: Published: Sep 25, 1992. Publicly Released: Oct 23, 1992.

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Pursuant to a congressional request, GAO provided information on whether: (1) the Environmental Protection Agency's (EPA) proposal is the most effective approach for identifying and repairing vehicles that exceed emission standards; and (2) EPA has studied alternative test procedures to reduce emissions from motor vehicles.

GAO found that: (1) there are drawbacks to the IM240 test procedure for both the identification and repair of out-of-compliance vehicles which could hamper the test procedure's effectiveness; (2) over 25 percent of the vehicles that EPA tested using the IM240 test failed an initial test but passed a second emissions test, even though no repairs were made; (3) vehicles that fail the IM240 test may be more difficult to repair because of trouble in diagnosing the cause of emission problems, mechanics not being trained in emission repairs for high-technology vehicles, and the inability of repair shops to afford IM240 equipment to replicate emission tests and determine whether repairs were effective; (4) EPA has suggested to states that they could use an alternative to IM240 if the alternative were an effective substitute, but states are reluctant to evaluate another option due to lack of expertise or resources; and (5) some state officials believe the proposed EPA inspection and maintenance (I&M) regulation is ambiguous about when EPA is proposing to allow states with seriously polluted areas to make a commitment to a specific I&M test procedure.

Recommendations for Executive Action

  1. Status: Closed - Implemented

    Comments: Recommendation was made to assure that states do not mistakenly commit to enhanced IM program prematurely. EPA took action but since it represents clarification rather than change, no financial savings or other nonfinancial benefits have occurred. Clarification was published in the Federal Register by EPA on November 5, 1992.

    Recommendation: To ensure that states have a clear understanding of when EPA is requiring them to make a commitment to a specific test procedure, the Administrator, EPA, should clarify in the final regulation that the agency intends to allow states until November 1993 to make a commitment to a specific test procedure.

    Agency Affected: Environmental Protection Agency

  2. Status: Closed - Implemented

    Comments: EPA's study on alternative test procedures was completed and published on May 11, 1993.

    Recommendation: To help ensure the long-term acceptance and success of the emissions reduction program, the Administrator, EPA, should expedite the agency's study of an alternative test procedure to the IM240 test so that EPA can provide specific guidance to the states on whether a viable alternative to the IM240 test exists prior to November 1993, which is when EPA is proposing to allow states to submit a final determination on their I&M program.

    Agency Affected: Environmental Protection Agency

  3. Status: Closed - Implemented

    Comments: The agency has conducted a number of workshops with the repair industry to discuss the IM240 program and to provide training on the repair of out-of-compliance vehicles. Even though this is an ongoing program and it may take years before significant reductions in vehicle emissions are achieved, EPA has clearly initiated action designed to help states and the repair industry implement effective I&M programs.

    Recommendation: As EPA works towards implementing a more stringent I&M program, the Administrator, EPA, should direct the agency to work closely with the states and the repair industry to resolve the issues related to the identification and repair of out-of-compliance vehicles discussed in this report.

    Agency Affected: Environmental Protection Agency


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