Standards of Performance for Existing Sources

Under Clean Air Act section 111(d), EPA issues guidelines to states on how to establish standards of performance for existing source of air pollutants that, if new, would otherwise be subject to new source performance standards. States must develop and submit state plans that establish and provide for implementation and enforcement of the standards of performance.

Affordable Clean Energy Rule

On July 8, 2019, EPA promulgated the Affordable Clean Energy Rule, or ACE Rule, and finalized repeal of the Obama-era Clean Power Plan. The Affordable Clean Energy Rule sets emission guidelines for state plans that are narrowly tailored toward in-the-fence-line measures that can be taken to reduce carbon dioxide emissions from coal-fired power plants. A copy of the final rule can be accessed here:

In developing a state plan, the Division of Environmental Quality must follow both the procedures established by the Affordable Clean Energy Rule and those codified at Ark. Code Ann. 8-3-201 et seq. On September 20, 2019, the Arkansas Legislative Council granted the Division a waiver of review and approval procedures for emission plans from the Legislative Council for emissions plans based on the Division’s determination that the final Affordable Clean Energy Rule did not require any of the following:

  • Shifting generation from electric generating units powered by one fuel type to another fuel type;
  • Closing any fossil fuel-fired electric generating unit; or
  • Imposing a statewide greenhouse gas goal or other statewide greenhouse gas emissions limitation.

Emission Guidelines for Municipal Solid Waste Landfills.

In 2016, EPA issued guidelines for reducing emissions from existing municipal solid waste landfills. In 2017, EPA announced that the agency was reconsidering certain aspects of the emission guidelines. In August 2019, EPA issued revisions to the emission guidelines to align state plan timing with requirements under the updated Clean Air Act section 111(d) implementing regulations finalized on July 8, 2019. EPA plans to promulgate a federal plan for municipal solid waste landfills by November 6, 2019. The Division of Environmental Quality is seeking input on whether:

  • The Division should accept delegation of the federal plan; and/or
  • The Division should petition the Arkansas Pollution Control and Ecology Commission to adopt standards of performance for municipal solid waste landfills so that the Arkansas can submit a state plan to replace the federal plan.

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A copy of the 2016 emission guidelines can be accessed here:

A copy of the 2019 revisions to the emission guidelines can be accessed here:

A copy of the 2019 proposed federal plan can be accessed here: