Air Quality

Under the 1990 Clean Air Act Amendments, the Rogue Valley (Jackson County, Ashland, Phoenix, Talent, Medford, Jacksonville, Central Point, White City, and Eagle Point) became a nonattainment area for particulate matter (PM₁₀). These communities shared a common airshed, known as the Medford-Ashland Air Quality Maintenance Area. During the 1980s, particulate pollution in the AQMA reached some of the highest levels in the nation and violated the federal air quality health standards also known as National Ambient Air Quality Standard. This violation meant two things:

1. DEQ needed to write a plan to bring the Medford-Ashland AQMA back into compliance with the standard; and
2. Added restrictions would be placed on Rogue Valley communities to limit new and expanding industries and significant transportation projects would need to be reviewed to determine their compliance with the plan.

The plan and rules addressing industry and residential woodstove curtailment were prepared by DEQ in 1991. The Environmental Quality Commission adopted the plan and rules shortly thereafter. All emission reduction measures adopted by the EQC were successfully implemented and air quality monitoring in the AQMA demonstrated that the PM₁₀ standards were met in 1992. The Medford-Ashland AQMA currently meets the PM₁₀ standards and EPA’s tougher new standards for fine particulate (PM_2.5).

On December 10, 2004, the EQC approved an updated PM₁₀ attainment and maintenance plans. This plan continues all of the PM₁₀ strategies from the 1991 attainment plan and continues the strictest requirements for managing emissions growth from future new and expanding major industry under the New Source Review program. EPA approved the plans in 2005.

Supporting documents

• Maintenance Plan for PM₁₀
  • Table of contents
  • Introduction and description
  • Emissions
  • Dispersion modeling
  • Attainment and Maintenance Demonstration
  • Maintenance Analysis
  • Industrial Area Analysis
  • Reduction measures