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<br />Battle Mountain Gold <br />NOPV Abatement Requirements <br />page 3 <br />(6) Cyanide Detection, Interception, Containment and Remedial Treatlment: <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 t e heap <br />leach and implement a contained vat processing system. This a ended <br />process was designed to yield detoxified tailings for disposal within the <br />tailings area. BMG replaced the originally proposed heap leachl double <br />liner system with leak detection with a single liner system without leak <br />detection. This amendment was approved by the Division relying upon <br />BMG's representation that tailings Cyanide levels would not exceed 3.8 <br />ppm WAD Cyanide and 4.4 ppm total Cyanide. <br />In the absence of a leak detection system, migrating leakage frpm 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 vicinity 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 Holt 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 dispos 1 area. <br />At a minimum the Division believes that all existing ground wat r <br />monitoring wells should be deepened or redrilled to ensure continuous <br />penetration of the ground water table. Further, the Division believes <br />that all tailings area monitoring facilities should be sampled onthly <br />and the analytical results reported expeditiously to the Divisi~n. This <br />evaluation report as a technical revision prior to May 29, 1992. <br />Further, BMG shall develop and submit a tailings effluent leaka~e <br />interception, containment and treatment plan for impacted grown, water, <br />surface water and soil. This plan shall be submitted to the Division as <br />a technical revision prior to June 15, 1992. <br />Status: Unresolved - BMG has committed to development of remedial plan <br />in letter of April 16, 1992. <br />- The requirements for monitoring plan amendment were <br />only advanced by the Division on April 21„ 1992. <br />(7) Amendment of Ore Processing Methodology: <br />BMG's preliminary suspicions of altered metallic ore content, a d the <br />coincidental failure of the designed processing cyanide recover circuit, <br />are indications that the ore processing methodology currently b ing <br />applied by BMG may require significant modification. If BMG de ermines <br />it necessary to modify its ore processing methodology, BMG shal~ submit <br />appropriate permit revision applications to the Division. Appr priate <br />permit amendments, supported by comprehensive analytical results and <br />