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addition at the crusher is increased. This increase in the lime added to the crushed ore compensates for the lack of lime in the run-of-mine material. As an example, if the rate of lime addition prior to loading run-of-mine were about 5.0 pounds per ton of ore, the rate will be increased to about 7.5 pounds per ton during placement of run-of-mine ore, based on [he proportion of crushed ore to run-of-mine delivered [o the Facility. The lime addition may, thus, be consider as on a [ruck load-by-truck load basis. The additional lime is distributed in the Valley Leach Facility by placing the run-of-mine ore in the same location within the Valley Leach Facility as the crushed ore with higher lime content is placed. The two ores are dumped or pushed together onto the advancing face of the ore lift so as to create the "shingle" effect that you have observed. This process places run-of-mine ore in close proximity to crushed ore and, therefore, in close proximity to the extra lime in the crushed ore. The lime added from the lime storage silo at an increased rate during delivery of run-of-mine ore to the Valley Leach Facility is, therefore, prorated throughout that part of the Facility in which run-of-mine ore is being placed. The mixing process is completed when leach solution percolates through the crushed ore with elevated lime content and enters the run-of-mine ore at a slightly higher than normal (for the leach solution) pH. In summary, the compensation is accomplished by prorating the lime in the Valley Leach Facility on a truck load-by-truck load basis and distributing the ore in a manner which places the run-of-mine ore in contact with crushed ore containing a higher (than normal) lime concentration. The second question inquires as to the protocol of the water transmission testing performed on the run-of-mine ore, and states: "CC&VG reports that the run-of-mine material is significantly higher in transmissivity, which should enhance eventual flushing detoxification. Who supervised and who performed these tests? What were the specific testing and monitoring protocols observed?" [n its letter of October 16, 1996, CC&V presented the results of tests of both run-of-mine and crushed ore. These were tests performed "in-house" by CC&V and employed vertical columns filled with test material i^ accordance with established procedures to generate the "time to "break-through" of solution applied to top of the columns. As CC&V described in this earlier letter, run-of-mine material consisting of the minus 6" portion was loaded into vertical 10" diameter columns. Identical columns were loaded with crushed material (the full size fraction). Solution was applied to the top of the columns at measured rates. The time until water appeared at the base of the column was measured. At a flow rate of 0.0004 g/m/ft2, 4-foot columns demonstrated break-through times of 753 minutes for the crushed material and 864 minutes for 2