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,' ~ ~' Processing Plan Circuit The San Luis plant or mill facility with associatied beneficiation tanks is engineered as a fully-containedlarea, i.e., continuous cement slab and curbing to contain pottential spillage. Some minor spills from leach tanks have occurred but have been completely contained in this area with no reSease to the environment. Tailings Pile Leak Detection BMR believes the MLRD reference is to the leak detection system incorporated into the double-lined collection p~nd located below the tailings facility. Some seepage through theiprimary liner during start-up was reported to MLRD. The prima y liner has been repaired and seepage has been significantly r duced. BMR believes the secondary synthetic liner and compact d subgrade has not allowed any of the primary liner seepage to es ape into the environment. Monitoring well M-9 is located downg adient from the collection pond as well as the tailings facility and, as noted above, has reflected no change in water quality. Pieaometers Piezometers placed in the tailings embankment to easure potential pore pressure as a result of a phreatic surf ce build- up has not indicated any significant build-up of pore ressure according to design engineers Steffen Robertson and Ki sten. Lysimeters Three sets of vacuum lysimeters consisting of two lysimeters per set are located below the tailings facility as required by the water rights decree. All the lysimeters have been consistently dry with the exception of L3W-4392 which as reflected small amounts of natural moisture. While th sample volumes were too small to obtain reliable analytical r sults, BMR nevertheless had the samples analyzed by Acculab. The enclosed analytical data indicates a total cyanide concentration at the detection limit. These analytical results refl ct the effects of the small sample volumes and resultant anal tical interference in the cyanide analyses. Please refer to the enclosed correspondence from Dr. Adrian Smith for a through discussion of the analytical results. Dr. Smith concl des that the data sets are invalid due to sample size and do no reflect the presence of cyanide in the sample.