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<br />Battle Mountain Gold <br />NOPV Abatement Requirements <br />page 3 <br /> <br />(6> Cyanide Detection, Interception, Containment and Remedial Trea}ment: <br />BMG originally proposed the construction of a heap leach at th$ San Luis <br />mine. In 1988, BMG amended its permit application to delete tlhe heap <br />leach and implement a contained vat processing system. This a~hended <br />process was designed to yield detoxified tailings for disposal within the <br />tailings area. BMG replaced the originally proposed heap leach double <br />liner system with leak detection with a composite liner system without <br />leak detection. This amendment was approved by the Division r$lying upon <br />BMG's representation that tailings Cyanide levels would not exgeed 3.8 <br />ppm WAD Cyanide and 4.4 ppm total Cyanide. <br />In the absence of a leak detection system, migrating leakage fdom the <br />tailings disposal ponds would only be detected by the five ground water <br />monitoring wells (M-5, M-6, M-7, M-8 and M-9) located in the v cinity of <br />the tailings area. Since the inception of the approved monitoring <br />program, only monitoring well M-9 has intercepted ground water, The <br />analytical results from samples collected from well M-9 have nqt detected <br />any Cyanide occurrence. <br />The Division directs BMG to reevaluate its approved program for ground <br />water monitoring, sampling and analysis for the tailings disposal area. <br />At a minimum the Division believes that an expanded monitoring program, <br />including additional ground water monitoring wells, should be implemented <br />to ensure continuous penetration of the ground water table. Further, the <br />Division believes that all tailings area monitoring facilities should be <br />sampled monthly and the analytical results reported expeditiously to the <br />Division. This evaluation report shall be submitted to the Di~lision as a <br />technical revision prior to May 29, 1992. <br />Further, BMG shall develop and submit a tailings effluent leak ge <br />interception, containment and treatment plan, to be implemented in the <br />event of contaminant migration from the tailings area. This cc}ntingency <br />response plan should specify methods to remedy contamination o ground <br />water, surface water and soil. This plan shall be submitted tq the <br />Division as a technical revision prior to June 15, 1992. <br />Status: Satisfied - BMG has committed to development of remediial plan <br />in letter of April 16, 1992. <br />The requirements for monitoring plan <br />were only advanced by the Division on <br />BMG verbally committed to modify the <br />on April 22, 1992. <br />(7) Modification of Ore Processing Methodology: <br />modittication <br />April 21 , 1992. <br />monitoring plan <br />BMG's preliminary suspicions of altered metallic ore content, and the <br />coincidental failure of the designed processing cyanide recovery circuit, <br />are indications that the ore processing methodology currently being <br />