The Mill Creek RI/FS was finalized in September 1987, 

 and a Record of Decision (ROD) was filed by the EPA in 

 October 1987. The remedial alternative chosen was permanent 

 relocation of all Mill Creek residents. By August 1988 AMC 

 had purchased all of the remaining properties and demolition 

 of the homes was completed by fall 1988. 



With the Mill Creek problem at the forefront, Anaconda 

 Smelter RI/FS activities remained on hold through much of 

 1987. The Anaconda Minerals Company conducted some reclama- 

 tion work on Smelter Hill (the smelter was demolished between 

 1982 and 1985) , and the EPA conducted soil sampling in the 

 communities of Anaconda, Opportunity, Warm Springs, Galen, 

 and Deer Lodge. 



A new "umbrella" administrative order between EPA and 

 AMC, which includes all subsequent operable units, was signed 

 in September 1988. Planned activities include RI/FS studies 

 of Smelter Hill, flue dust, and the Old Works. This work 

 will be performed by the Anaconda Minerals contractor, PTI 

 Environmental Services. 



Contaminants identified at the Anaconda Smelter Super- 

 fund site include arsenic, beryllium, cadmium, copper, lead, 

 and zinc, and there are likely some organic contaminants on 

 Smelter Hill. Flue dust, a waste that is highly contaminated 

 with arsenic and heavy metals, is located in various areas on 

 Smelter Hill and is being addressed as a separate operable 

 unit. EPA and state personnel are reviewing results of a 

 pilot process that extracts valuable metals and converts the 

 arsenic to a more stable compound. This and other processes 

 will be considered as possible remedies along with other 

 alternatives identified in the RI/FS. 



The Old Works area, which is the site of the first 

 smelters in Anaconda, is probably of most immediate concern 

 to the Clark Fork system. Warm Springs Creek, which is a 

 tributary of the Clark Fork, flows through the middle of the 

 Old Works area very close to deposits of slag and tailings. 

 These wastes have elevated levels of contaminants, and some 

 are within the floodplain of the creek. Although the Stage I 

 RI/FS studies showed Warm Springs Creek water to be generally 

 of good quality (Tetra Tech 1987) , there is potential for 

 water quality degradation in a large runoff or flood event. 

 The RI/FS studies of the Old Works will likely lead to the 

 removal of at least some of the contaminant sources, thereby 

 increasing the chances that Warm Springs Creek will continue 

 to deliver good quality dilution water to the Clark Fork 

 system. 



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