Gazelle Creek. Aside from a few abnormal cells, the upper site on Gazelle Creek had 

 excellent biological integrity. At the lower site, an elevated number of abnormal cells, an 

 elevated percentage of motile diatoms, and slightly depressed species richness and diversity 

 suggest minor impairment from sedimentation and possible chronic metals toxicity. Otherwise, 

 this site had excellent biological integrity. The two sites shared slightly more than half of their 

 diatom assemblages, indicating only minor changes in environmental conditions between them. 



Buford Creek. Buford Creek supported a large number of motile diatoms that 

 approached the threshold for moderate impairment and partial support of aquatic life uses. The 

 pollution index value at this site approached the threshold for minor impairment. Other metrics 

 indicate good to excellent biological integrity. 



Blaine Spring Creek. The upper site on Blaine Spring Creek (at bypass) supported a 

 distincti\e diatom flora dominated by Achnanthidiiim minutissimum. Other major species here — 

 Diatoma mesodon and Slaiirosirella leptostaiiron — indicate cold gently flowing waters t>pical of 

 spring creeks. The fourth major taxon at this site, Planothidium lanceolatum, is adapted to living 

 attached to sand grains and suggests a sandy substrate. The low species richness and diversity 

 values here are probably due to consistently cold water temperatures. 



A major change in the diatom assemblage and environmental conditions occurred 

 between the upper site and the site below the fish hatchery. The latter site had a depressed 

 pollution index indicating elevated loading of organic compoimds and minor impairment. 

 Otherwise, this site had good biological integrity and provided full support of aquatic life uses. 



The pollution index rebounded at the lower two sites on Blaine Spring Creek, indicating 

 reduced loading of organic compounds. However, these sites supported elevated numbers of 

 motile diatoms that resulted in siltation index values in the minor impairment range. These two 

 sites were similar, floristically, and shared about half of their diatom assemblages. 



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