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9 <br />analyses: RS-5 (copper, iron, zinc and sodium); upper tailings impoundment (total and WAD <br />cyanide), lower tailing impoundment (total and WAD cyanide), collection impoundment <br />(total and WAD cyanide); M-9 (WAD cyanide); and M-13 duplicate (WAD cyanide). All <br />samples were unfiltered. <br />Acceptable control limits for spike analyses is ±75-125% of the known value, and acceptable <br />control limits for duplicate analyses is ±20%RPD. Spike analyses performed on the <br />collection impoundment sample for both total and WAD cyanide were outside control limits <br />(133% for both total and WAD cyanide). In the November 15, 1992 letter (.Appendix E), <br />Core Laboratories explains this high recovery as being related to the dilution necessary for <br />the high color of the sample. Dilution of the sample prior to adding the spike would have <br />resulted in a more reliable spike recovery value. All other spike recoveries were within <br />control limits. As discussed in Section 3.1.2, duplicate analyses for total cyanicJe performed <br />on both the upper and lower tailings impoundments were outside of control limits. All other <br />duplicate analyses were within control limits. <br />The color dilution also explains a discrepancy between values reported ir. the Quality <br />Control Report and the Analytical Report for the collection impoundment sample. The <br />original total cyanide values for the collection impoundment and lower tailings impoundment <br />samples (932003-4 and 932003-6, respectively -- see Quality Control Report, Appendix D, <br />pg. 1) are different than those reported in the Analytical Report. The origin total cyanide <br />value in the Quality Control Report for the collection impoundment was 0.26 nng/1, while the <br />concentrations in the Analytical Report were 1.05 and 1.14 mg/1. Similarly, the original total <br />cyanide values in the Quality Control Report for the lower tailings impoundment were 0.29 <br />mg/1, while the concentrations in the Analytical Report were 0.58 and 0.31 mlg/1. A similar <br />problem exists for original WAD cyanide values for the collection impoundment sample. <br />The original WAD cyanide value in the Quality Control Report (Appendix D, pg. 6) for the <br />collection impoundment was 0.16 mg/1, while the concentrations in the Analytical Report <br />were 0.62 and 0.72 mg/l. All other concentrations in the Quality Control Report match <br />those reported in the Analytical Report. The values reported in the Quality Control Report <br />area 1:4 dilution made to dilute the color in the sample (personal communication, Core <br />Laboratories, Dec. 28, 1993). If the total and WAD cyanide concentrations reported in the <br />Quality Control Report are multiplied by 4, (0.26x4=1.04; 0.16x4=0.64 mg/1), the <br />concentrations (with rounding) are the same as the first duplicate reported in the Analytical <br />Report. <br />33 LABORATORY TURNAROUND TIME <br />Core Laboratories received the samples on October 13, 1993. The date of the Analytical <br />Report from Core Laboratories was November 18, 1993, which is a turnaround time of over <br />one month. <br />RCG/Hagler, Bailly, Inc <br />