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B. ANP/AGP Results The ANP/AGP results for the second sample set are included in Attachment 3. These results are very similar to results from previous testing and from ongoing quarterly humidity cell testing for the San Luis tailings material. Sulfur values range between l and 2% with very low neutralizing material available. Mr. Logsdon's memo presents a comparison of the ANP/AGP results to pre- operational tailings samples and to samples from the original test program for the Reclamation Evaluation Report. All values are comparable. As a result. BMRI made a decision that humidity cell testing of the second sample set was not necessary or warranted given the similarities to previous testing. C. 1312 Leachability Results The 1312 leachability test results were also very similaz to previous results from both pre- operational testing and from the original Reclamation Evaluation sampling program. The results indicate that the leachates are low in major ions and there are very few detectable +alues for metals. As concluded in the pre-operational testing and supported by both the original Reclamation Evaluation geochemical test program and these results, the San Luis tailings will not pose a threat to water quality as a result of leaching of the tailings by meteoric waters. IV. Tailings Underdrain Water Quality In order to fully understand and evaluate the tailings pore water and the potential ibr high cyanide values in the pore water, BMRI also evaluated the change in the underdrain water quality over time. Results of bi-weekly testing of the underdrain for cyanide have been submitted to the Division on an ongoing basis. These results are not going to be repeated in this submittal, however a brief summary is worth noting. When the original and subsequent sampling of tailings was occurring in 1992 and 1993, the tailings underdrain cyanide levels were rapidly decreasing. The monthly average information is presented below. 6/92 92 mg/I W.4D 7/92 5~ mg/I WAD 8/92 43 mg/I WAD 9/92 37 mg/l WAD 10/92 34 mg/1 W.4D 11/92 30 mg/1 WAD 12/92 27 mg/( WAD 1/93 21 mg/l WAD 2/93 15 mg/1 WAD 3/93 14 mg/1 WAD The decrease combined with the lack of cyanide in the tailings pore water collected as part of the second sample set indicate that the high cyanide deposited as part of the AVR deposited tailings is rapidly degraded and/or dissipated. The decrease continued although the rate slowed as the values