based upon frequency and duration of use. User attitude and use demand are 

 frequently combined in a matrix to determine final sensitivity levels. 



DEGREE OF VISIBILITY 



A distance zone is ttie area that can be seen from a sensitivity area, and 

 is described as foreground, middleground, background, or seldom seen. Distance 

 zones are delineated on the premise that the ability to perceive change or 

 detail in the landscape is a function of distance. 



Specific site information (Scenic Quality, Visual Sensitivity, and Degree 

 of Visibility) is initially displayed on separate topographic maps. A hier- 

 archy of importance is established and the maps are combined. The resulting 

 classifications are the basis for defining minimum management objectives 

 and the degree of acceptable alteration for each landscape classification. 

 The determination of the degree of acceptable alteration for each landscape 

 unit is defined utilizing a numerical rating system that enables a decision 

 maker to see exactly what feature (landform, water, vegetation, structures) 

 is being af fee ted and to what extent. This method a I lows some flexibility in 

 determining appropriate mitigation measures. 



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