STUDY NUMBER ; 6.4 ( COMPLETED ) 



ORGANIZATION ; Environmental Protection Agency (EPA) 



TITLE OF STUDY ; Algal Assays Performed on Waters Collected from 

 the Clark Fork River System 



CONTACT ( S ) ; Dick Montgomery, Environmental Protection Agency, 



Montana Office - 499-5486 



Loren Bahls, Montana Department of Health and 

 Environmental Sciences, Water Quality Bureau- 

 444-2406 



Joseph Greene, Environmental Protection Agency, 

 Corvallis, Oregon 



DURATION ; 1984 - 1985 



CURRENT STATUS : Algal assays, using Selenastrum capricornutum , 

 were undertaken at the request of the Montana Water Quality Bu- 

 reau. The tests are performed with water samples shipped to 

 the Corvallis Environmental Research Laboratory. The assays 

 are conducted according to methods outlined in the S. capricor- 

 nutum Algal Assay Bottle Test (Miller, Greene and Shiroyama, 

 1978). 



Water samples from nine stations on the Clark Fork River 

 below Milltown Dam were collected and assayed on three dates: 

 December 10-14, 1984; May 10-16, 1985; August 6-8, 1985. 



A second set of algal assays were conducted with water ob- 

 tained from 9 stations on Silver Bow Creek, Warm Springs Pond 

 and the upper Clark Fork River downstream to Turah. The assays 

 were part of the Remedial Investigation on the Silver Bow Super- 

 fund site. These tests were performed to define the effects 

 of heavy metals, phosphorus and nitrogen on the potential growth 

 of planktonic algae within the Silver Bow, Warm Springs and upper 

 Clark Fork River systems. 



PUBLICATIONS AND REPORTS ; 



Results of Algal Assays Performed on Water Collected from the 

 Lower Clark Fork River System on Stations below Milltown Dam 

 to below Noxon Dam: 



Rept. I; December 10-14, 1984 Sampling; prepared by J. 

 C. Greene et al . US EPA, Corvallis, Oregon. 



Rept II: May 10-16, 1985 Sampling; prepared by J. C. Greene 

 et al . US EPA, Corvallis, Oregon. 



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