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As was discussed in the October 1 submittal, the primary purpose of the sampling program was to verify the original program results showing little to no cyanide present in pore water in tailings deposited at high cyanide values, therefore measurement of cyanide in pore water was critical. A vacuum pump was used to pull pore water from the samples to measure pore water cyanide values. The pore water to be tested for cyanide content was pumped to a bottle containing preservative so that maximum cyanide retention occurred and little was lost to degradation. Pore water was limited in the samples, but all samples were tested for a number of water quality parameters. Note that the small sample volume meant that the samples could not be filtered. As such, metal ~ analyses, using an acidic preservative, may have dissolved some small particulate matter causing ~~alues to be elevated over actual pore water quality values. Additional geochemical testing for the samples included AGP/ANP tests and 1312 leachability for both rinsed and unrinsed samples. These results are presented in Attachment 3 and discussed below. A. Pore Water Quality As was discussed in the Reclamation Evaluation Report, BMRI collected a sample of tailings pore water within the AVR deposited tailings during the original program. This one sample showed cyanide levels at 0.83 mg/I weak acid dissociable (WAD) cyanide and 0.88 mg/I total cyanide. Both values were surprisingly low and Dr. Adrian Smith, geochemical consultant to BMRI, indicated that additional samples should be taken. Dr. Smith's concerns with sampling methodology are discussed in detail in the October 1, 1993 submittal. As a result, BIvIRI collected five additional pore water samples under Dr. Smith's direction in September 1993 from within the tailings deposited while the AVR system was in use. The cyanide results for all pore water samples are shown on Table 1. Note that the highest WAD cyanide value was 0.83 mg/1 obtained from the pore water sample in the original program. The highest total cyanide value was ~.1 mg/I. All values were significantly below the values in the :ailings at the time of deposition. This would indicate that high cyanide water was rapidly degraied and/or dissipated from the system. Other constituents measured within the pore water were also within the expected ntnges based on previous testing. As expected values for sodium, calcium and potassium were relatively high in the pore water. Metals were low to non-detectable for those metals which would not be increased through addition as part of a processing reagent or as a result of the lack of sample filtering. Iron, manganese, molybdenum, copper and zinc are all present in the pore water at valur:s that are higher than would be anticipated in actual tailings pore water and in other samples of tailings water previously presented. Dr. Smith evaluated the pore water chemistry as part of his evaluation of the geochemical test results for the second sampling program. His evaluation is presented in a memo included as Attachment 4. Mark Logsdon of Geochimica was also asked to provide his comments on the pore water quality and tailings geochemistry from the second sample set. Mr. Logsdon s comments are included as Attachment ~. [V1r. Logsdon overlooked the unfiltered nature of the tailings pore water analyses in his evaluation and as a result, his discussion of the high iron in the port: water is not accurate and should be disregarded. 3