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Memo to Board BMRI Compliance Deadline page 3 Mountain Gold Tailings". Briefly, the liquids entrained within the pre-July, 1992 tailings contain cyanide levels significantly in excess of the permit standards. Up to 7.8 years will be required for, these fluids to drain to the collection pond. Their inclusion in th collection pond makes it impossible for the collection pond t attain the permit standards. As the following summary of recorded WA cyanide levels demonstrates, the collection pond cyanide levels are responding to treatment by mixing but much less rapidly than the tailings ponds. Further, because the highest cyanide content liquids have yet to reach the collector bed, I anticipate that cyanide levels in the effluent to the collection pond may increase during the 7.8 year purging c cle. (4) The chemical responsiveness of the tailings ponds to the imple entation of the INCO treatment process will be limited by the ability t circulate the liquids in the standing tailings pool through th ore processing circuit. Unlike the invasive Hydrogen Peroxide tre tment process reaction which occurred in the ponds, the INCO process occurs within the INCO reactor vessel. BMRI projected the ability of the ore processing circuit to treat the standing tailings pool as a po tion of TR-004, the CYTOX treatment revision. BMRI estimated that 21 ays was required to circulate the standing pond liquids through the pl nt. Further, in order to accommodate dispersion and mixing within he pond BMRI assumed that two cycles (42 days) might be required to ex ose all tailings liquids to the process. I believe this is an appropriate assumption in this instance as well. Therefore, if processing commences on October 15th, the tailings ponds standing pools should achi ve compliance with the permit standards by November 26, 1992. Therefore, if a realistically achievable compliance deadline is to b imposed upon Battle Mountain Resources, Inc., I believe the Board should imp se the date of November 30, 1992, and limit its application to the tailings ponds. The Division may recommend additional corrective actions be applied o the collection pond in future months. Ascertaining Compliance In order to enforce the compliance deadline it will also be necessar for the Board to specify the standard to be applied in judging compliance. n approving TR-010, the Division approved the use of a simple 30-day a erage method to determine compliance with permit cyanide levels. BMRI is equired to perform total and WAD cyanide analyses on a minimum of four compo ite pond samples taken five to nine days apart. The average of these analyse for a 30-day period determine compliance for the month. The application o the 30-day average method will make it impossible to determine compliant before December 30, 1992. Therefore, for purpose of timely judging complia ce with the imposed compliance deadline, the Board would need to impose an instantaneous single sample standard.