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<br />6.4.7 EXHIBIT G -Water Information <br />10. The applicant states on page 14 that a gravel well permit and temporary substitute supply <br />plan will be submitted to the Colorado State Engineer for approval. In accordance with Rule <br />3.1.6(1) please provide a written commitment to provide correspondence from the Office of the <br />State Engineer verifying that a gravel pit or other type of well permit, as applicable has been <br />secured prior to exposure of groundwater at the Stagecoach Pit. Attached is a copy of review <br />comments from the Office of the State Engineer. Please respond. <br />11. The applicant states on page 15 that an annual accounting of the consumptive use of the <br />mining operation's water needs is required to be submitted to the State as part of the Substitute <br />Supply Plan. In accordance with Rules 6.4.7(3) and 6.4.7(4) please provide the following: 1) an <br />estimate of the project water requirements including flow rates and annual volumes for the <br />development, mining, and reclamation phases of the project, and 2) the projected amount from <br />each of the sources of water to supply the water requirements for the mining operation and <br />reclamation. <br />12. The applicant has provided a commitment, on page 8, to monitor groundwater levels upslope <br />of the slurry wall. The applicant has also provided a commitment, on page 14, to conduct <br />groundwater monitoring prior to and throughout the life of the mining operation, and to <br />implement mitigation techniques if necessary. In accordance with Rule 3.1.6(1), the Division <br />requests that the applicant clarify or provide the following: <br />a) Please quantify the rise in elevation of the groundwater table upslope of the completed slung <br />wall that will constitute a "mounding effect", ie: what is the trigger or threshold? <br />b) Please provide a revised copy of the mining plan map to show the locations of the four (4) <br />piezometers upslope of the slurry wall. <br />c) Please define the frequency (monthly, quarterly, etc.) of groundwater monitoring to be <br />conducted both prior to excavation and throughout the dewatering and mining operation. <br />d) Please define the mechanism for submittal of groundwater monitoring data to the Division. <br />(As an example, you may include the previous year's monitoring data in the Annual Report). <br />e) The Division prefers that at least three (3) consecutive months worth of groundwater level <br />measurements be obtained prior to mining to develop a set of baseline monitoring data. <br />Twelve (12) consecutive months worth of baseline data would be ideal since that would <br />provide seasonal variation throughout the yeaz; however, the Division realizes that may not <br />be feasible in the case of the Stagecoach Pit. Please define the number of months worth of <br />baseline data that will be collected prior to the start of excavation at the Stagecoach Pit. <br />f) Please quantify the number of feet drop in groundwater elevation that will constitute a <br />"significant" drop due to mining and will trigger the need for mitigation to ensure the <br />performance of a neighboring well, within 600 feet of the affected land. <br />