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• comminuted material (overburden) over a significant portion of the previously disturbed areas <br />and the rehabilitation and water management on orphan sites within the district, water and <br />air have significantly more difficulty gaining direct access to the underground workings. As <br />a result, there is less rapid oxidation of sulfides in the diatreme, and less rapid flushing of the <br />underground workings by precipitation and surface water captured by the surface openings to <br />the mines. This has resulted in the quality of the regional ground water sampled at the <br />Carlton Tunnel portal to be improving, with less zinc, less TSS, and less flow variation. <br />W. Under Volume 5 Executive summary the operator states "The pregnant solution from the <br />Cresson project VLF will be fully contained within the existing Phase I, II & Phase IV PSSAS <br />or the 20 million gallon Phases I, Il &III external pond. Unless the External pond is <br />connected to the valley leach facility as the rest of the pregnant ponds located in Phase <br />I, II, & IV ponds, this pond is approved to only be used on an emergency basis. The <br />solution to be stored in this pond can not exceed 20 ppm WAD cyanide after it is treated <br />with hydrogen peroxide, and as such it is not considered by the DRMS, to be part of the <br />valley leach facility. Even though the design was similar to the existing pregnant ponds <br />in the valley leach facili , as requested by the Division, with its own GW monitoring <br />well, it was never intended to store solution for extended periods with similar <br />concentration of cyanide as the pregnant ponds. At present CC&V is utilizing the pond <br />to store fresh water to be used as makeup water in the valley leach facility. If CC&V <br />wants to utilize this pond as a pregnant pond, the same infrastructures that are utilized in <br />the existing pregnant ponds have to be in place and a Technical Revision to the permit <br />• addressing these changes must be submitted. <br />Response: <br />DRMS is correct that the existing emergency storage pond (ESP) was proposed and approved <br />under Amendment No. 8 for emergency purposes associated with the VLF with the <br />installation of a cyanide destruction circuit and construction/certification for usage (i.e., <br />triple liner system, and Low Volume Solution Collection System (LVSCS)). CC&V has no <br />plan at the current time to utilize the ESP as a pregnant pond, rather, CC&V presently <br />intends to use this pond as a storage pond for fresh water make-up to be added to the process <br />circuit. Should CC&V determine the need to utilize the ESP as a pregnant pond in the <br />future, the DRMS will be notified prior to that happening. As approved under Amendment <br />No. 8, should CC&V give notice to DRMS to use the ESP as a pregnant pond, CC&V will <br />maintain the requirement to store neutralized process solution at equal to or less than 20 ppm <br />WAD CN. <br />X. CC&V proposes to change the water balance from the current static model to a dynamic <br />model utilizing the Golder and Associates created modeling program called Gold Sim. <br />Even though the Division does not object in principle about the change, we do have some <br />concerns about the proposed change. First DRMS would like to see the module, for the <br />program as stated above, so we can understand the input parameters. <br />• Response: <br />Please see CC&V's response above under Section VIX <br />4.1