Action Memorandum 



" These include primary and secondary standards from a variety of sources and are presented only to 



assist in characterizing the potential for contaminants in a release. 



However, the lime precipitation water treatment plants are not effective in treating 

 the cyanide, nitrate, and selenium from the leach pad process solution. An estimated 

 129 million gallons of residual cyanide process solution is stored above the leach pads 

 within the leach pad circuits, with additional accumulations expected in the future 

 from water infiltration. In 2001, the agencies built a bioreactor water treatment 

 system on the Landusky mine site with remaining construction bonds from Pegasus" 

 surety to treat the heap leach solutions that drain from the leach pads at the mine. 

 Because the ore placed on the heap leach pads was treated with alkaline materials to 

 enhance the gold recovery process, the heap leach solutions are not yet acidic, but 

 they are generally too high in selenium, nitrates, and cyanide to meet stream 



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