achieve maximum detection limits, carbon furnace techniques 

 will be utilized for the heavy metal analysis.) 



At least eleven groundwater monitoring wells will be 

 installed; several of these will be monitored quarterly for 

 the same water quality parameters analyzed during the surface 

 water collections. All presently existing wells and springs 

 within the project area will be sampled for their water 

 quality and water yield. 



Seven aquatic invertebrate and periphyton stations will 

 be sampled three times per year, during pre-runoff , summer 

 low flow and autumn. Species present and their abundance 

 will be reported. Diversity indices will be calculated. 



The Montana Department of Fish, Wildlife and Parks will 

 conduct baseline fishery resource investigations on Rock 

 Creek and on the Clark Fork River above and below the 

 confluence of Rock Creek. Fish population estimates will be 

 conducted on five stations on Rock Creek. Spawning migra- 

 tions from the Clark Fork River will be monitored. The 

 tissue from twenty-five game fish, collected from each of 

 three locations on Rock Creek, will be analyzed for their 

 heavy metal content. Gill net sampling and snorkeling 

 observations will be conducted in the Clark Fork River near 

 Rock Creek. 



FUTURE ACTIVITIES ; The above monitoring will continue for 

 two and possibly three, field seasons. Upon completion of 

 the baseline studies, ASARCO will likely apply for an 

 operating permit from MDSL. This will trigger the EIS 

 process, which may require the collection or analysis of 

 additional aquatic resource information. 



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