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the rock and the potential leachate can be predicted and understood through the life of the <br />overburden storage areas. This will also help in determining the appropriate lime <br />amendment as discussed under item "H" above. <br />B. The description of the "additional conservative design features "for the ECOSA, is a bit <br />confusing. On page 11-10, last paragraph, 6th line, a statement is made that the footprint <br />area of the ECOSA will be left in a roughened condition to encourage the infiltration into <br />the Grassy Valley feeder. Later, measures are described to "minimize infiltration through <br />the pile". What hydrologic component is being encouraged to infiltrate to the Grassy Valley <br />feeder and why ?Is the roughened condition of the footprint designed to inhibit saturation <br />of the ECOSA, while at the same time facilitate infiltration that may originate as percolation <br />through the ECOSA, and runoff from the ECOSA and surrounding area that migrates <br />beneath the ECOSA toward the feeder ? It is not explicitly stated in the section, but is the <br />advantage of channeling infiltration to the feeder to facilitate capture by the Carlton <br />Tunnel? <br />C. The DRMS is not fully convinced that all the drainage from the Grassy Valley area will <br />report to the diatreme, and benefit from the reported abundance of neutralization potential <br />before discharging through the Carlton Tunnel. In order for the DRMS, to be comfortable <br />with your conclusions, please provide a detailed deep drill core data correlation that shows <br />the deep drill core data from Grassy Valley area is similar to deep drill core data from other <br />areas with in the diatreme. <br />D. The operators consultant in explaining how the diatreme flow rate is channeled thru the <br />Carlton Tunnel utilized the flowing assumptions. <br />a) Moffat Tunnel. <br />1. "Flow from the tunnel ceased when tunnel at lower elevations reduced the <br />water level in the diaterme below the elevation of the tunnel". This statement <br />is not accurate. When Amendment # 6 was approved by DRMS, the MLRB <br />instructed the Division to monitor the flow rate in the Tunnel. CC&V placed <br />a weir inside the portal at approximately 1200 feet or less from the portal <br />entrance, at the Iron Smart stope, due to concerns raised by part owner of the <br />portal Mr. Chuck Dagger. The Division has recorded flow rates from this <br />weir ranging from 55 gpm to 110 gpm, which drain to underground <br />workings inside the tunnel. Granted no flow rate is observed from the portal, <br />but there is a recorded flow rate data for the tunnel. Please explain. <br />b) Roosevelt Tunnel <br />1. Again the operator states "flow from the tunnel largely ceased when the <br />Carlton Tunnel was installed at a lower elevation ". Flows from the <br />Roosevelt tunnel have never ceased and continue to flow to Cripple Creek. <br />The argument used by CC&V, when requested by the Colorado Department <br />of Public Health and Environment (CDPHE), to permit the discharge from <br />the tunnel was, to prove there was no connection from the areas being <br />impacted by CCWS current activities up gradient of the tunnel discharge. <br />A flow rate from the portal has been measured by both the DRMS and <br />CC&V and data should be available. Please explain. <br />8