the DHES should move quickly to select the preferred 

 alternative and get work underway. Funding should be 

 obtained from the responsible party. 



Floodplain Mine Wastes 



Large areas of the upper Clark Fork floodplain are 

 covered by river-borne mine waste deposits or tailings 

 disposal areas (e.g. Colorado Tailings) , the result of 

 historic mining practices in which the Clark Fork was viewed 

 mainly as a convenient means of waste disposal. These mine 

 waste deposits are sources of contamination to soils, 

 surface water, ground water, aquatic organisms, and other 

 media. Once-vital riparian areas have been lost, and the 

 mine wastes are considered blights on the landscape. 



The floodplain of the upper Clark Fork lies within the 

 boundaries of the Silver Bow Creek Superfund site. It is 

 anticipated that remedial or corrective actions to deal with 

 the mine wastes will be implemented as part of the Superfund 

 process. EPA and DHES have prioritized various areas within 

 the site. Areas that pose human health hazards take 

 precedence over those that pose environmental concern, and 

 because the Superfund process is an arduous one, cleanup 

 along the floodplain may be many years away. 



This section contains recommended actions to address 

 some aspects of the floodplain mine waste problems in the 

 upper Clark Fork. Reclamation of key areas along the 

 floodplain could reduce the frequency of acutely toxic 

 concentrations of metals in the upper river. Any management 

 plan for the upper Clark Fork should consider how remedial 

 actions would affect pH and alkalinity, as these parameters 

 largely control the distribution of metals in the river. The 

 actions outlined below should complement and perhaps expedite 

 the Superfund process. 



1. Identify priority streamside mine wastes. 



a. Review existing maps of streamside mine wastes in 

 the upper Clark Fork to determine if these maps are 

 adequate or if more mapping is needed. 



b. Review existing water quality data (particularly 

 metals loading data) to help identify and priori- 

 tize streamside mine waste areas best suited for 

 reclamation. 



5-6 



