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<br />10 <br />3.2 Analytes Determined <br />According to the MOU between Colorado Division of Minerals and Geology (DMG) and <br />BMRI (pg. 5), the third party sampling contractor shall have the samples analyzed only for <br />total cyanide, WAD cyanide and copper. If analytical interferences are suspected to exist, <br />the third party monitor may direct the laboratory to determine additional parameters, with <br />the concurrence of the DMG project manager, after notification of BMRI. As agreed upon <br />by BMRI before collection of the first sample, the third-party monitor accepted splits of <br />more than the sample types outlined in the sampling agreement (see Tables 1 and 2). <br />There seems to be some confusion about the analytes that are to be determined in the <br />process point samples (tailings and collection ponds). The TR-0006 document lumps the <br />process points in with the ]ysimeter samples when discussing both collection and handling <br />methods (Section 4) and protocol for analysis (Section 6). The implication in Section 6 is <br />that Table 2 provides the list of analytes to be determined in both the lysimeter and the <br />process point samples. However, only the analytical methods for total and WAD cyanide, <br />copper, zinc, iron, calcium and sodium are discussed (pg. 41). Table 2, which is labeled: <br />i_,ysimeter Water Quality Parameters;' calls for the colleciiuti of tuial metals samples <br />(footnote 3), yet dissolved metals samples were collected for the process point samples. <br />Taking dissolved samples for metals that may interfere with cyanide analyses makes no sense <br />if the cyanide samples are not filtered. If anything, using dissolved metals concentrations to <br />correct for interferences in cyanide analyses on unfiltered samples will underestimate the <br />cyanide concentrations in the samples analyzed. <br />There are other parameters that are not determined that should be considered, including: <br />total metals in groundwater samples if unfiltered iron is significantly greater (>+20%) than <br />filtered iron; sulfide, anions, and the full list of metals in process paint san;ples; and ar, <br />important constituents in reagents or the ore/waste rock that are not included in the list of <br />analytes. <br />33 Potential Interference with Cyanide Analyses <br />The collection pond sample was taken from the collection pond return line tap instead of <br />from the collection pond feeder ditch, as described in TR-0006 (October, 1992; pg. 31 ). <br />Both the sample from the tap and the feeder ditch water had a solid greenish material in <br />*.hem. This green mat-like material was removed in the filtration process, According to <br />BMRI, the green material began to form after they added hydrogen peroxide to the tailings <br />ponds and collection pond to treat excess cyanide. Without knowing what this material is, <br />it is impossible to evaluate what its effect would be on analytical results from unfiltered <br />samples. However, it is possible that it could interfere with cyanide analyses, which are <br />performed only on unfiltered samples. It is known that fatty acids and nitrate/nitrate <br />RCG/Hagler, Bailly, Inc. <br />