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Air Plan Approval; Iowa; Air Quality Implementation Plan-Muscatine Sulfur Dioxide Nonattainment Area and Start-up, Shutdown, Malfunction SIP Call Withdrawal

On October 23, 2020, the Administrator of the EPA Region 7 Office signed a final rule to approve a State Implementation Plan revision submitted by the state of Iowa for the 2010 SO2 Muscatine, Iowa nonattainment area and to withdraw the SSM SIP Call for Iowa that was issued as part of the 2015 SSM SIP Action.

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