samples. Negative values signify a decrease in the parameter while a posi- 

 tive value indicates an increase. The column entitled "upstream to down- 

 stream" for each parameter indicates the net affect of the mined site on the 

 water quality during the site visit. There was significant seasonal vari- 

 ation, as indicated by the results from Oregon Creek, Penny River, Kavik 

 River, and McManus Creek, which makes complete analysis of the data of 

 questionable value. There appeared to be some sedimentation associated with 

 remnant instream depressions and this sediment was subject to scour during 

 high f I ow . 



Changes in other parameters were observed with temperature and dis- 

 solved oxygen showing the greatest frequency of change (Table 38). The 

 temperature and dissolved oxygen changes resulted from the reduction of 

 velocity and spreading of flow over the mined area, a situation which occur- 

 red at many of the study sites. The ORP values did not change significantly, 

 indicating the absence of heavy organic loading. Conductivity values changed 

 in the mined area at several study sites, possibly indicating the exposure 

 of a spring. The differences, judging by the age of the mined areas (i.e., 2 

 to II years), were probably not caused by the dissolving or precipitation of 

 substances in the mined area. Spring sources were identified at Penny River 

 and Dietrich River- Upstream, both of which showed altered conductivity. A 

 spring source may be indicated at the Aufeis Creek and Skeetercake Creek 

 mined areas, but the conductivity change at McManus Creek may have been a 

 meter malfunction because the change was not observed during the other two 

 site visits. 



The water qual ity parameters in inundated pits were general ly quite 

 different from those in the associated river (Table 59). Summer temperatures 

 were normally higher and dissolved oxygen levels lower in the pits. An excep- 

 tion was the Dietrich R i ver-Upstream pit where spring flow kept the water 

 temperature low throughout the summer. Thermal and oxygen stratification 

 were evident at the West Fork Tolovana River and Tanana R i ver-Upstream pits. 



280 



