Plans for maintaining air quality

We work with local clean air agencies and communities with air quality issues to make sure specific areas keep meeting national air quality standards. These Maintenance State Implementation Plans target areas that, at one time, failed to meet air quality standards. Maintenance plans are related to attainment state implementation plans.

Public comment

We propose revisions to Washington's State Implementation Plan for air quality. These revisions show Washington's ability to maintain, enforce, and implement federal air quality standards to keep an area meeting national air quality standards.

State Implementation Plan documents Comment or request a public hearing

We propose to send EPA the revised air quality State Implementation Plan (SIP) to redesignate the Intalco‑Ferndale Sulfur Dioxide Nonattainment Area due to improved air quality and approve the 10‑year maintenance plan for the area.

Public comment period:  March 27, 2024 – April 26, 2024

Comment or request a public hearing online

Mail comments to:
Anya Caudill, Air Quality Program
Washington Department of Ecology
P.O. Box 47600; Olympia, WA  98504-7600

Tentative public hearing:
(if requested by April 26, 2024)
May 14, 2024, 6 p.m. online

For more information, contact Anya Caudill at 360-791-5499.

Accessibility
To request ADA accommodation for the public hearing, email ADA coordinator or call 360‑407‑6831, 711 (relay service), or 877-833-6341 (TTY).

State Implementation Plan documents Public comment

None at this time

 

Accessibility
To request ADA accommodation for the public hearing, email ADA coordinator or call 360‑407‑6831, 711 (relay service), or 877-833-6341 (TTY).

What is a Maintenance State Implementation Plan?

There are 14 areas in Washington where we worked with local clean air agencies and communities to reduce air pollution and return those areas to meeting national air quality standards.

When an area does not meet national air quality standards, the area is classified by EPA as in "nonattainment." When an area returns to meeting national air quality standards, we ask EPA to re‑classify the area as in attainment and in maintenance.

Once an area is in maintenance status, the federal Clean Air Act requires states to implement a Maintenance State Implementation Plan. A maintenance plan includes strategies to keep meeting national air quality standards in that area for 20 years.

A Maintenance State Implementation Plan includes:

  • A current, comprehensive inventory of emissions.
  • Enforceable measures to reduce emissions. These measures may include a combination of state, local, and federal rules, plans, administrative orders, and permits for specific sources.
  • A demonstration that the measures will keep the area meeting national air quality standards for 20 years.
  • Contingency measures that will be applied if the area re-violates national air quality standards.

Washington air quality maintenance areas

The map below shows boundaries of air quality maintenance areas in Washington. The map also shows the locations of national parks and wilderness areas (also called "mandatory federal Class 1 areas," in darker green), which have special protection for visibility. Click on a shaded area of the map to open a pop-up window with more information (name, pollutant(s) being maintained, end date(s) of the 20-year maintenance period, and the clean air agency in charge of that area).

Click on a shaded area of the map to open a pop-up window with more information (name, pollutant(s) being maintained, end date(s) of the 20-year maintenance period, and the clean air agency in charge of that area).