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<br />If the three samples collected as described above are all in excess of the "trigger level," CC&V <br />shall propose to the OMLR water-quality control that will cause the parameter concentration <br />level to return to compliance levels or CC&V will reassess the entire baseline data to determine <br />if the concentration suggesting a potential exceedence is, in fact, within the predicted range of <br />ambient values. CC&V also has the option to demonstrate to the satisfaction of the OMLR, in <br />accordance with a time schedule approved by the OMLR, that the measured levels are protective <br />of ground water uses. <br />Other Ouestions: A few questions arose for which it was agreed formal clarification from <br />CC&V would be helpful. These questions involved, principally, the quality of leach solution <br />that would be contained in the spent ore at the time the ore had been prepared for regrading and <br />reclamation. [n particular, there was a discussion about the dynamic (humidity cell) testing <br />conducted of the two samples of Cresson valley leach ore, that is, the interim data which the <br />OMLR was provided via CC&V's letter dated October 13, 1998. <br />1. The two samples of ore from Cresson Valley Leach facility collected for humidity cell testing <br />were collected randomly from the ore that has been deposited, principally during the first half <br />of 1997. As described in our letter to the OMLR dated October 13, 1998, the samples were <br />comprised of randomly-collected aliquots from a number of locations on the surface of the <br />placed ore. This ore represents across-section of ore materials placed on the valley leach <br />facility. The collected and tested ore is believed to be "representative" from the standpoint of <br />the general mineralogy of ore that had been placed through 1997 as well as ore that will be <br />placed after 1997. This is based on the "randomness" of the ore mining and placement on the <br />leach facility. Variability of ore mineralogy in terms of affecting the pH of solution contacting <br />that ore is compensated for, if necessary, by the rate of lime addition to the ore. Such <br />compensation would be adjusted if the pH of the leach solution were to decrease. Therefore, <br />the potential effect of higher sulfide content of ore would be mitigated by the CaCO, additions. <br />Samples of ore would, then, reflect both the ambient acid neutralization potential and the acid <br />neutralization potential provided by the lime. <br />For clarity, the addition of lime is accomplished by distributing approximately 4.5 pounds of dry <br />lime to one ton of ore passing from the crushers. The lime is mixed in the ore as the ore is <br />transferred along the overland conveyor, as the ore is loaded into the surge bin at the load-out <br />terminus of the conveyor, as the ore is transferred to haul trucks, and as [he ore is placed on the <br />valley leach facility. <br />2. With respect to alkalinity measured in the humidity cell samples, again, the ore is prepared <br />by adding lime to the "dry" oreZ rather than by adding lime to the leach solution. The pH of <br />the ore is indirectly measured by measuring the leach solution pH because the leach solution pH <br />controls the sodium cyanide content in that solution. <br />= The ore to which lime is added will, normally, have a moisture content on the order of 6.5 percent as a result <br />of (1) ambient moisture and (2) water and surfactant addition for dust control throughout the crushing circuit. <br />9 <br />