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  2. Air Quality Implementation Plans

Summary of Seattle-Tacoma Puget Sound Area Ozone Maintenance Plan

Related Information
  • Washington SIP: EPA Approved Nonregulatory Provisions and Quasi-Regulatory Measures (40 CFR part 52.2470(e)) Table 2

Background

The Seattle-Tacoma Puget Sound Area was redesignated attainment for ozone on November 25, 1996.

Washington submitted an ozone maintenance plan on January 28, 1993, and EPA approved the plan on September 26, 1996 (61 FR 50438 (pdf) (6 pp, 189 KB)).

Summary

The plan relies on control strategies needed to assure attainment of the National Ambient Air Quality Standards (NAAQS) for ozone. The strategy focuses on vehicle Inspection and Maintenance Program in conjunction with the Federal Motor Vehicle Emissions Improvement Program.

Rules

  • WAC 173-422, Motor Vehicle Emission Inspection
  • PSCAA Regulation II

Contingency Measures

Improvements to existing Motor Vehicle Inspection and Maintenance Program (within the current statutory authority of the Department of Ecology) including upgrade to Acceleration Simulation Mode (ASM1) test procedure.

Mandatory reduction in gasoline volatility.

EPA Effective Date

November 25, 1996

Air Quality Implementation Plans

  • About Air Quality Implementation Plans
  • Approved Air Quality Implementation Plans
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Contact Us about Air Quality Implementation Plans
Contact Us to ask a question, provide feedback, or report a problem.
Last updated on April 11, 2025
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