distribution was determined by the f requency-by-number method. In addition, 

 the underlying material was measured using hydraulic sieves and the size 

 distribution determined by percentage-by-weight. 



The river bank materials were described at cross section locations 

 based on a subjective evaluation and photographed for documentation. Ma- 

 terial gradation samples of river bank materials were not obtained. 



Channel Processes. The fluvial morphology at each site was assessed 

 using comparative aerial photography. In the field, fluvial morphological 

 features were verified and documented in more detail, e.g., gravel bar 

 types, bed formations, scour holes, and sediment deposition. Degradation 

 and/or aggradation upstream from, and downstream from the gravel removal 

 site were investigated. 



River Ice. In the field, evidences of ice processes (breakup jams, 

 ice scour, gouging, and aufeis) were documented to help evaluate the role 

 of ice on the river morphology. 



Water Qua I i ty 



Water quality parameters measured were temperature ( C), dissolved 



2 

 oxygen (ppm), conductivity (m i cromhos/cm ), turbidity (JTU), suspended 



solids (mg/S,), oxidation-reduction potential (MV), and pH (Table 2). Water 



quality measurements were taken at the aquatic macro i nvertebrate sample 



sites. Usually the measurements were taken along a transect across the river 



or pit with the number of replicates within a site adjusted to the size of 



the water body. The measurements were normal ly within 30 cm of the water 



surface, although depth profiles were taken in pits. 



Aquat i c Biol ogy 



Introduction. Field emphasis was placed on aquatic Invertebrates, 

 changes in fish distribution in relation to the gravel mined area, and 

 potential fish spawning and rearing habitat during the ice-free period. 



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