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`~ Letter to Andre' Douchane, BMRI Comments regarding June 25, 1992 Order page 2 , Primary to formulating our "belief" (opinion) will be thorough, acc rate and correlated monitoring of the cyanide levels within the tailings pon . Yesterday, Gary Dodson contacted Dr. Harry Posey with several inqui,ies regarding the necessity of continuing daily monitoring in the processing plant and tailings pond once the Sampling and Analytical Protocol (TR-006 is approved. In my opinion, the two topics are relatively unrelated. !Once the Protocol is adopted it will provide the methodology for tonducting 11 required water quality sampling and monitoring at the site. Decisi ns ' concerning the frequency of conducting monitoring relate to the req irements within your plan, including orders imposed by the Board, and the to hnical requirements for demonstrating statistical validity. Each process ontrol situation should be considered on its specific individual scientifi and environmental needs. In response to Gary's inquiry, I don't believe daily monitoring of he processing stream is necessary any longer. However, in light of th imposed requirements of the June 25, 1992 Board Order, I think continued co prehensive monitoring of the pond is critical. Further, Gary informed Harry that Degussa's personnel would leave the San Luis site on Thursday, July 2, 1992, which would curtail their daily monitoring of the tailings pond WAD cyanide levels. Gary reported that Degussa's WAD cyanide analysis determine the level to have reached approximately 40 ppm as of yesterday, but the MRI's on site testing reported approximately 55 ppm. Apparently, BMRI's meth d consistently reports a higher level by approximately this relationship. I'm a realist. Obviously, the other parties to these proceedings mad/ not be. I understand that the various testing techniques have various bias' bnd interferences. However, the Division must formulate its "belief" on July 20th based on the evidence in hand. If the monitoring results are not ve ifiable, BMRI's commitment to achieving the lowest reasonably achievable cyanide levels could be suspect and might be challenged. BMRI presented monitoring results to the Board on June 24, 1992, whi h depicted the results of Core Lab's and Degussa's analyses. I recomm nd that BMRI continue to accumulate this data, for consistency. If you prop se to discontinue the Degussa method and implement an alternative, I recom end that you apply both techniques and the Core lab methodology simultaneousl to split samples for three to five days. If the techniques correlate accepta ly, i.e. with a consistent correction factor, BMRI could justify the use of t e alternative methodology. Plots of the continuing WAD Cyanide data c uld then be prepared using the correction to relate Degussa to BMRI's on site data string. The Core lab methodology should include the "APHA/AWWA Stan and Methods, 17th edition, method 4500-C" analysis specified in paragrap (1) of the Board Order, in accordance with Dr. Adrain Smith's recommendatio The Core Lab data could then be used to tie the daily Degussa/BMRI data o the protocol standard from Core Labs.