On the use of decision analysis in determining significant visibility impairment

Abstract In the United States, the 1977 Clean Air Act Amendments and subsequent regulations provide federal land managers with a responsibility to protect visibility against significant impairment within selected wildernesses, parks and other so-called mandatory Class I areas. This paper outlines a decision analysis approach to help in identifying critical decision points for federal land managers in determining the degree of visibility protection appropriate for Class I areas. The paper reviews visibility related responsibilities of Class I managers and describes options available to them. It also identifies current information and potential data on the economic and social values of air visibility which could be used with the decision tree approach and gives an overview of the state of the art of quantifying those values.