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Affordable Clean Energy (ACE) Rule

The Clean Power Plan’s Replacement

On December 28, 2017, EPA published an Advanced Notice of Proposed Rulemaking, seeking information from the public and stakeholders regarding certain components of the Clean Power Plan.1 In the notice, EPA requested information and input on the following:

  • The roles and responsibilities of states and federal agencies in developing emission guidelines, control requirements, “best system of emission reduction” (BSER), and related regulations
  • The application of Clean Air Act Section 111(d) to power plants under EPA’s new interpretation in its repeal of the previous Clean Power Plan
  • Interactions with the Clean Power Plan and other programs including New Source Review and New Source Performance Standards

Comments were due to EPA by February 26, 2018. ADEQ submitted comments to EPA.

ADEQ’s Official Comments to EPA | Download >

The Final ACE Rule was promulgated by EPA in July 2019.

On July 8, 2019, EPA published a Notice of Final Rulemaking promulgating its ACE Rule.2 In this same rulemaking, EPA also rescinded the Clean Power Plan and established new regulations for Clean Air Act § 111(d) state plans. 

ADEQ’s Planning Process

On November 8, 2019, we held an initial stakeholder meeting to discuss the ACE Rule planning processes. We plan to hold additional meetings during the development of Arizona’s state plan. ADEQ is required by Clean Air Act § 111(d), the ACE Rule, and Arizona Revised Statutes 49-459 to develop a state plan that establishes standards of performance for carbon dioxide emissions from certain fossil fuel fired electric generating units.

November 8, 2019 Agenda | Download >
November 8, 2019 Meeting Presentation | Download >

On April 23, 2020, ADEQ and representatives from the affected coal-fired electric generation units commenced a technical working group.  This group meets on a monthly basis to address technical issues regarding the heat rate improvement (HRI) analysis of the EPA’s identified Best System of Emissions Reductions as mandated by the ACE Rule.
We will continue to engage in a robust stakeholder process and will  hold future stakeholder meetings which will be announced at a later date | Subscribe to Receive Updates >