STUDY NUMBER ; 9.2 



ORGANIZATION ; U.S. Geological Survey (USGS), Montana Office 



TITLE OF STUDY ; Hydrology and Water Quality of Shallow Aquifers 

 along the Clark Fork from Warm Springs to Milltown, Western Mon- 

 tana 



CONTACT ( S ) ; Tom Brooks - US Geological Survey, Helena Office 



- 449-5263 



-V Joe Moreland - US Geological Survey, Helena Office 



- 449-5263 



OBJECTIVE ; To assess the occurrence of ground water in shallow 

 aquifers along the Clark Fork from the headwaters to the con- 

 fluence with the Blackfoot River near Missoula and to assess 

 the occurrence and magnitude of chemical constituents, including 

 toxic metals, in water in those aquifers. Specifically, the 

 project will determine (1) characteristics of ground water flow 

 systems, (2) seasonal changes in the systems, (3) quality of 

 ground water in the systems, (4) basic mechanisms for evolution 

 of ground water quality, and (5) relationships between ground 

 water and surface water flow quality. 



CURRENT STATUS ; The study will obtain existing data from USGS 

 files and other federal and state agencies. Existing data will 

 be supplemented by; (1) selective field inventory of existing 

 wells, (2) installation of test wells, (3) conducting seepage 

 runs along the upper Clark Fork, (4) establishing a network of 

 wells for periodic water level measurement, and (5) establishing 

 a network of wells for annual water quality sampling. 



Using data collected during this study and other existing 

 data from state and federal agencies, geochemical models, such 

 as WATEQF and WATEQ2, may be used to determine equilibrium re- 

 lationships in water. Lithographic samples will be obtained 

 for analysis of mineralogy and selected metal concentrations. 



FUTURE ACTIVITIES ; Installation of wells and sampling will con- 

 tinue through FY 88. 



PUBLICATIONS AND REPORTS 



A report will be available in 1989. 



i4€ 



