|EDGAR, RON - Spokane Regional Clean Air Agency|
Submitted to: Atmospheric Environment
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/23/2011
Publication Date: 7/21/2011
Citation: Sharratt, B.S., Edgar, R. 2011. Implications of changing PM10 air quality standards on Pacific Northwest commmunities affected by windblown dust. Atmospheric Environment. 45:4626-4630.
Interpretive Summary: Wind erosion has historically resulted in violation of the PM10 Air Quality Standard in the Inland Pacific Northwest. The EPA is considering the adoption of a new PM10 Air Quality Standard. The new PM10 Standard would require the daily PM10 concentration to be no greater than 65 or 85 µg m-3, which is lower than the current Standard (daily PM10 concentration no greater than 150 µg m-3). Adopting a new PM10 Standard with a threshold PM10 concentration of 85 µg m-3 will likely have no impact on the number of violations of the PM10 Standard. However, adopting a new PM10 Standard with a threshold PM10 concentration of 65µg m-3 may result in more violations encountered in eastern Washington. To comply with possible changes to the PM10 Air Quality Standard, agronomists and soil scientists must intensify their efforts to identify management practices that control wind erosion of agricultural lands in the Inland Northwest.
Technical Abstract: The US Environmental Protection Agency (EPA) is currently reviewing the National Ambient Air Quality Standards (NAAQS) for Particulate Matter. EPA is considering the recommendation to change both the form and level of the PM10 (particulate matter =10 µm in diameter) Standard. The implication of the recommended NAAQS for PM10 on air quality is explored in this study. Daily observations of PM10 were made at Kennewick and Spokane, WA from 2000 through 2010. The number of violations of the PM10 Standard was determined for both the current (not to exceed 150 µg m-3 on more than one day per year) and recommended (not to exceed 65 or 85 µg m-3 based upon the 98th percentile) Standards. The current PM10 Standard has only been violated at Kennewick. Under the recommended PM10 Standards, Kennewick would have violated the Standard at both the 65 and 85 µg m-3 levels while Spokane would have violated the Standard at only the 65 µg m-3 level. The results of this study suggest that the recommended NAAQS for PM10 using a level of 85 µg m-3 will tend to result in fewer violations of the Standard and using a level of 65 µg m-3 will tend to result in more violations of the Standard in the Inland Pacific Northwest. The Exceptional Event Rule and research on management practices to control the emission of fugitive dust will continue to be important strategies for achieving compliance with PM10 Air Quality Standards in the Inland Pacific Northwest.