Letter from Carol Browner
June 5, 1997
Honorable Dan Glickman
United States Department of Agriculture
Washington, D.C. 20250
Dear Secretary Glickman:
As you know, the U.S. Environmental Protection Agency (EPA) has proposed revisions to the national ambient air quality standards for particulate matter and ground-level ozone. Recently there have been a number of reports mischaracterizing the effects these proposed revisions would have on agriculture. This letter is intended to clarify my position on this matter.
In the U.S. Department of Agriculture comments on the proposed revisions to the ozone and particulate matter standards, USDA raised concerns about the potential effects that implementing control programs could have on farms. I want to make it clear that agriculture would not be the target of EPA control strategies designed to attain these new standards.
In fact, any decision to strengthen the existing ozone standard would benefit agricultural production. As research at the USDA, EPA, and elsewhere has shown, ground-level ozone damages many kinds of plants and crops including: soybeans, wheat, cotton, peanuts, and various trees including: black cherry, white pine, aspen and ponderosa pine. A standard equivalent to the standard proposed by EPA in November 1996 would substantially reduce damage to crops, tree seedlings and other vegetation.
EPA will work with states to focus any ozone emissions reductions strategies on sources located in urban and highly populated areas including power plants, motor vehicles, and large industrial facilities. Ozone control strategies will not focus on agricultural sources.
With respect to particulate matter, EPA has been analyzing actual samples of fine (e.g. PM 2.5) particles in the air to determine the sources of the particles. In so doing, it is clear that farms are actually among the smallest sources of PM 2.5 in areas likely to have fine particulate problems. While farm activities contribute some primary PM 2.5, secondary particles such as sulfates are by far the largest component of PM 2.5. The major sources of fine particles include sulfates from power plants and nitrates from power plants and other large combustion sources. We intend to work with states to target the PM 2.5 monitoring program on urban areas with large populations.
If EPA does add a PM 2.5 standard, I intend to issue guidance to the states to ensure that in meeting that standard they focus their control strategies on sources of fine, rather than coarse particles. Thus, if we establish a new PM 2.5 standard, EPA would not focus regulatory attention on farming and tilling.
With regard to prescribed burning on federal lands and open burning on agricultural lands, EPA recognizes the natural role of fire in wildland ecosystems and agricultural land, and will continue to work with USDA to develop air quality strategies that accommodate the role of burning. I look forward to working closely with you on this matter.
In summary, agricultural sources are a very small part of the overall PM 2.5 problem and will actually benefit from a tightened ozone standard. I look forward to continuing to work with you and USDA's Agricultural Air Quality Task Force to address farming issues as we continue work on these important public health standards. I agree with the Task Force recommendation that it would be beneficial for USDA and EPA to enter an agreement to share technical expertise on agricultural air quality issues.
Carol M. Browner
Posted on USDA Task Force on Agricultual Air Quality Web Site on June 30, 1997