20 



Mr. Synar. Professor White, your testimony will also be made a 

 part of the record. We ask you to summarize in about 5 minutes. 



STATEMENT OF WARREN H. WHITE, PROFESSOR, 

 WASHINGTON UNIVERSITY, ST. LOUIS, MO 



Mr. WHITE. Good morning, Mr. Chairman and members of the 

 committee. 



I am here to summarize the general conclusions and rec- 

 ommendations of the committee on haze in national parks and wil- 

 derness areas. I am sure that all my colleagues on the committee 

 are as delighted as I am at your expression of interest in our work. 



Our committee was convened by the National Research Council 

 at the beginning of 1990, and included people knowledgeable in me- 

 teorology, atmospheric chemistry and optics, air pollution monitor- 

 ing anamodeling, statistics, control technology, and environmental 

 law and public policy. 



We were charged to develop working principles for assessing the 

 relative importance of anthropogenic emission sources that contrib- 

 ute to haze in class I areas and for considering various alternative 

 emission control measures. 



The complete design of a program for protecting and improving 

 visibility in national parks and wilderness areas must involve 

 many policy issues that transcend science and the committee's ex- 

 pertise. However, present scientific knowledge about visibility im- 

 pairment has several important implications for policymakers seek- 

 ing to approach the national goal of remedying and preventing 

 man-made visibility impairment in class I areas. These implica- 

 tions include the following. 



Progress toward the national visibility goal will require limits on 

 the emissions of pollutants that can cause regional haze. A strategy 

 that relies only on influencing the location of sources, although per- 

 haps useful in some situations, would not be effective in general. 



Progress toward the national visibility goal will require regional 

 programs that operate over large geographic areas. Class I areas 

 cannot be regarded as potential islands of clean air in a polluted 

 sea. 



A program that focuses solely on determining the contribution of 

 individual emission sources to visibility impairment is doomed to 

 failure. Instead, strategies should be adopted that consider many 

 sources simultaneously on a regional basis, although assessment of 

 the effect of individual sources will remain important in some situ- 

 ations. 



Visibility policy and control strategies might need to be different 

 in the West than in the East. In the East, sulfates derived from 

 the SO2 emissions of coal-fired power plants account for about one- 

 half of all anthropogenic light extinction. Reductions in these emis- 

 sions that should occur in the next two decades as a result of the 

 acid rain control program alone are expected to yield a reduction 

 of about one-quarter in the average anthropogenic light extinction. 



In the West, no single source category dominates. An effective 

 western visibility strategy will therefore have to address many 

 source types, such as electric utilities, gasoline- and diesel-fueled 

 vehicles, petroleum and chemical industry sources, forest manage- 

 ment burning and fugitive dust. Moreover, present rapid popu- 



