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FLAG: Federal Land Managers'
Air Quality Related Values Work Group

The Federal Land Managers' Air Quality Related Values Work Group (FLAG) is comprised of the National Park Service (NPS), the U.S. Fish and Wildlife Service (FWS) and the U.S. Forest Service (USFS). FLAG was formed to evaluate air pollution effects on air quality related values (AQRVs) and to provide State permitting authorities and potential permit applicants consistent guidance regarding assessment of new and existing source impacts on AQRVs.

Based on knowledge gained and regulatory developments since the original FLAG report was completed in December 2000 the federal land managers have revised FLAG resulting in the FLAG 2010 report.


FLAG 2010 report cover.

November 2011—Nitrogen & Sulfur Deposition Analysis Guidance

October 2010—FLAG Phase I Report Revised

Guidance on Nitrogen and Sulfur Deposition Analysis Thresholds

A letter establishing FLM deposition analysis thresholds (DAT) for total nitrogen and sulfur, and an overview of the deposition analysis thresholds are available below.

December 2000 final FLAG Phase I report



National Park Service

Susan Johnson
Air Resources Division
P.O. Box 25287
Denver, CO 80225
(303) 987-6694

US Fish and Wildlife Service

Sandra V. Silva
Chief, Branch of Air Quality
7333 W. Jefferson Ave., Suite 375
Lakewood, CO 80235-2017
(303) 914-3801

US Forest Service

Ann L. Acheson
Air Quality Program
201 14th St. SW
Washington, D.C. 20024

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Last Updated: March 21, 2012