The following sections present the results of several 

 recent investigations that describe the physical and chemical 

 characteristics of ground water in the Clark Fork Basin. 

 These studies include: 



Summit and Deer Lodge Valley studies (Hydrometrics 



1983a) 

 Sludge injection site study (Duaime and Moore 1985) 

 Hydrogeology of the Colorado Tailings (Duaime et al. 



1987) 

 Phase I Silver Bow Creek RI studies (MultiTech 



1987a, b,c) 

 Stage I studies for Anaconda Smelter RI (Tetra Tech 



1986b) 

 Remedial action study for Milltown Reservoir (Woessner 



et al. 1984) 

 Sole source aquifer petition, Missoula Valley Aquifer 



(Missoula City-County Health Department 1987) 



Several studies are also ongoing, including Butte mine 

 flooding monitoring, Phase II Silver Bow Creek RI investiga- 

 tions, and a USGS study of the shallow aquifers in the upper 

 basin. 



Upper Silver Bow Creek Area 



The upper Silver Bow Creek area has received a tremen- 

 dous amount of attention in the last five years, and a fairly 

 large ground water data base has now been established. These 

 data are discussed below. 



Although the series of reports by Hydrometrics (1983a) 

 dealt primarily with rehabilitation options in the head- 

 waters, it generated or discussed some ground water data as 

 well. Hydrometrics reported degraded ground water quality in 

 the following areas: 



in the alluvium east of the Berkeley Pit and west 



of the South Dump 



near the Clark Tailings and City-County Landfill 



along Silver Bow Creek from Texas Avenue to the 



downstream end of the Colorado Tailings 



near the Ramsay Flats and other floodplain areas 



beneath and peripheral to the Opportunity Ponds. 



Phase I of the Silver Bow Creek Superfund hydrogeologic 

 investigations was conducted from January to July 1985 to 

 determine general contamination sources, evaluate the extent 

 and severity of ground water contamination, and examine 

 ground water-surface water relationships. As a result of 



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