# Federal Register #2026-22647

EPA approval of Maricopa County mobile-source emission reduction credit program

**Posted:** November 05, 2026
**Identifier:** 2026-22647

The U.S. Environmental Protection Agency approved an Arizona emissions-credit program for eligible vehicle retrofits and replacements in Maricopa County.
- **Government entities:** U.S. Environmental Protection Agency (EPA); Arizona Department of Environmental Quality (ADEQ); Maricopa County Air Quality Department (MCAQD).
- **Action:** EPA approved Arizona’s State Implementation Plan revision concerning MCAQD Rule 205 and added a related Economic Incentive Program support document to the Arizona plan.
- **Program:** Voluntary retrofits or replacements of existing on-road vehicles with lower-emitting vehicles can generate emission reduction credits. Major stationary sources may use the credits to offset nitrogen oxides and volatile organic compound emissions under Maricopa County’s Nonattainment New Source Review program.
- **OEMs and vendors:** No manufacturers, OEMs, resellers, or contractors are identified; no products or services are being solicited.
- **Procurement status:** This is a regulatory action, not a procurement opportunity or contract award.

### Description

The Environmental Protection Agency is taking final action to approve a revision to the Maricopa County portion of Arizona’s State Implementation Plan. The revision establishes a federally enforceable program for generating emission reduction credits by retrofitting or replacing existing on-road vehicles with lower-emitting vehicles. The credits may be used to offset emissions increases at major stationary sources under the Department’s Nonattainment New Source Review program. EPA found the revision meets applicable Clean Air Act requirements.

[View original listing](https://www.federalregister.gov/documents/2026/11/05/2026-22647/air-plan-revisions-arizona-maricopa-county-air-quality-department-new-source-review-emission)