biological integrity (minor impairment due to teratological 

 cells) and site 05 would have fair biological integrity due to 

 elevated percent dominant species and depressed diatom diversity 



REFERENCES 



APHA. 1998. Standard Methods for the Examination of Water and 

 Wastewater. 20th Edition. American Public Health 

 Association, Washington, D.C. 



Bahls, L.L. 1979. Benthic diatom diversity as a measure of 

 water quality. Proc . Mont. Acad. Sci . 38:1-6. 



Bahls, L.L. 1993. Periphyton Bioassessment Methods for Montana 

 Streams (Revised) . Montana Department of Health and 

 Environm.ental Sciences, Helena. 



Bahls, L.L. 1999a. Use Support in Big Spring Creek Based on 

 Periphyton Composition and Community Structure. Prepared 

 for the Montana Department of Environmental Quality, Helena. 



Bahls, L.L. 1999b. Effects Of An Oil Spill on The Composition 

 and Structure of the Periphyton Community in Casino Creek 

 and Big Spring Creek near Lewistown, Montana. Prepared for 

 the Montana Department of Environmental Quality, Helena, 

 Contract No. 200012. 



Bahls, L.L. 2001. Biological Integrity of Cottonwood Creek, 

 Fergus County, Montana, Based on the Composition and 

 Structure of the Benthic Algae Community. Prepared for the 

 Montana Department of Environmental Quality, Helena, 

 Contract No. 200012-3. 



Bahls, L.L., E.E. Weber, and J. 0. Jarvie. 1984. Ecology and 

 Distribution of Major Diatom Ecotypes in the Southern Fort 

 Union Coal Region of Montana. U.S. Geological Survey 

 Professional Paper 1289, U.S. Government Printing Office, 

 Washington . 



Bahls, L.L., Bob Bukantis, and Steve Tralles. 1992. Benchmark 



Biology of Montana Reference Streams. Montana Department of 

 Health and Environmental Sciences, Helena. 



Barbour, M.T., J. Gerritsen, B.D. Snyder, and J.B. Stribling. 



1999. Rapid Bioassessment Protocols for Use in Streams and 

 Wadeable Rivers: Periphyton, Benthic Macroinvertebrates and 

 Fish. Second Edition. EPA/841-B-99-002 . U.S. EPA, Office 

 of Water, Washington, D.C. 



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