^ Quality Assurance 



Several steps were taken to assure that the study results are accurate and reproducible. 



Upon receipt of the samples, station and sample attribute data were recorded in the 

 Montana Diatom Database and the samples were assigned a unique number, e.g., 2611-01 . The 

 first part of this number (261 1) designates the sampling site (Goat Creek Reach 16) and the 

 second part (01) designates the number of periphyton samples that have been collected at this 

 site for which data have been entered into the Montana Diatom Database. 



Sample observations and analyses of soft (non-diatom) algae were recorded in a lab 

 notebook along with information on the sample label. A portion of the rav/ sample was used to 

 make duplicate diatom slides. The slide used for the diatom proportional count will be 

 deposited in the Montana Diatom Collection at the University of Montana Herbarium in 

 Missoula. The other slide will be retained by Hannaea in Helena. Diatom proportional counts 

 have been entered into the Montana Diatom Database. 



• 



Results and Discussion 



Results are presented in Tables 3, 4 and 5, which are located near the end of this report 

 following the references section. The Appendix contains a series of diatom reports, one for each 

 sample. Each diatom report contains an alphabetical list of diatom species and their percent 

 abundances, and values for 65 different diatom metrics and ecological attributes. 



Sample Notes 



Goat Creek. The sample from Reach 16 contained moss, was very silty, and was 

 partially decomposed (smelled of H2S). The sample from Reach 9 contained some silt and 

 consisted mostly of Schizothrix colonies. The sample from Reach 7 was silty, partly 

 decomposed, and comprised mostly of Schizothrix crusts. The sample from Reach 3 contained 

 moss, was decomposing, and was very silty. Stalks of Didymosphenia (a diatom-) in this sample 

 appeared as tufts of dirty cotton. 



