Additional visits were conducted to specific sites if potential over- 

 wintering habitat or suspected spawning areas were present within the mined 

 area. 



Study sites were categorized into two groups. Eighteen sites were 

 visited once during the open water season. Seven sites with known fish 

 utilization in the mined area were subject to additional field study. These 

 seven sites were visited on three separate occasions during open water 

 conditions of I calendar year. In addition, seven pit sites where winter 

 utilization by fish was suspected were visited to document overwintering. 



The 18 sites subject to a less intensive field program were visited 

 only once. 



Selection of Sample Areas . Three sample areas were selected at all 

 sites: upstream, within the mined area, and downstream. Selection of up- 

 stream and downstream sample areas was based on similarity to the aquatic 

 and terrestrial characteristics exhibited in the mined area prior to gravel 

 removal. Selection of sample areas was made so that substrate, depth, width, 

 velocity, and poohriffle ratio were similar at the upstream and downstream 

 I ocat i ons. 



The upstream area was typical ly located at least 400 m above the mined 

 area and the downstream area was between 400 and 800 m below the mined 

 area. Selection of the 400 m criteria was based on the assumption that 

 the hydrological effect of gravel removal would be minimal that far up- 

 stream. Selection of a downstream area between 400 and 800 m below the 

 mined area was based on the probability that changes occurred in this area 

 either during or immediately after gravel removal. 



At sites with more than one mined area, additional sample areas were 

 selected to assess effects. Similar selection criteria were used. 



Selection of Sample Gear . Fish and aquatic macrolnver tebrate sampling 

 gear were selected relative to the types of habitat present. Features such 



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