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13 

 the Hadson Power 14 permit application. All three determinations were 

 based on demonstrations that sulfur dioxide (S02) emissions from the 

 individual facilities would adversely affect the air quality related 

 value (AQRV) of water quality in the Wilderness. 



Since 1992, the Forest Service has commented on two additional permits 

 for power facilities. Adverse impact determinations were not made in 

 these cases because the Forest Service was unable to quantify the 

 impacts of the emissions from the individual sources on the air 

 quality related values (AQRV's) of the Wilderness area. The Forest 

 Service bases its impact analysis on the results of emission transport 

 modeling conducted by the applicant. The models currently used are 

 only reliable up to 100 kilometers from the source. As a result of 

 the most recent permit review, SEI Birchwood, the Forest Service 

 requested that the Virginia Department of Environmental Quality 

 require large sources greater than 100 kilometers from the Wilderness 

 to model impacts using "Mesopuff II", a new computer model which can 

 handle transport over greater distances. 



How many State permit applications for new source reviews has the 

 Forest Service commented on in the last five years? How have these 

 generally been resolved? 



In the last five years, the Forest Service has commented on about 240 

 new source reviews. The Clean Air Act prescribes an "affirmative 

 responsibility" to Federal land managers of Class I areas with the 

 requirement to prevent significant deterioration (PSD) . The Forest 

 Service reviews permit applications and provides the state regulatory 

 agency or EPA with findings and recommendations regarding effects from 



