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and proposed mitigation measures please address the following: <br />a) Please quantify the predicted elevation change in groundwater levels due to mounding, in <br />the absence of the drain installation, ie: what is the magnitude of impact expected? <br />b) How will the proposed drain installation perform under a scenario of a `vet spring" <br />assuming snowmelt runoff conditions and several or more severe thunderstorm events <br />within a 3-5 day period of time? Or, severe flooding event such as a 25-year, 50-year, or <br />100-year flood? (Will the drain function as designed and be capable of routing excessive <br />flows from these possible scenarios?) <br />c) How will the Applicant demonstrate that the drain is functioning as designed and that the <br />predicted mounding of groundwater surfaces has been adequately mitigated? The <br />Division requests that the Applicant consider installation of a series of peizometers <br />surrounding the drain installation and monitor groundwater levels for a period of at least <br />three (3) years following completion of the slurry wall and drain installations to verify <br />that the predicted groundwater impacts (mounding) have been sufficiently mitigated. (If <br />the Applicant believes that the recommended peizometers and groundwater level <br />monitoring would not be necessary, please provide a discussion of why these measures <br />should not be employed. Please respond. <br />6.4.12 EXHIBIT L -Reclamation Costs <br />10. Because of the proposed configuration of the mine plan cells (7), slurry walls (2), perimeter <br />drains, lined ponds (3), unlined pond (1), areas requiring backfilling to original grade, the <br />Division requests that the Applicant revise the reclamation cost estimate to provide a <br />comprehensive itemized reclamation cost for each of the 2 Phases of the Operation. Each phase <br />with all reclamation components such as slurry wall installation, dewater trench installation, <br />backfill & grading of pit walls, backfill & grading of stockpiled overburden, topsoil replacement, <br />re-vegetation, installation of surface water drainage controls, etc. should be listed separately. <br />(The operator may apply for a partial release of reclamation responsibility as each reclamation <br />task/phase is completed. The Division will then re-evaluate the reclamation bond requirement at <br />that time to determine if a bond reduction is appropriate. Or, the operator may elect to apply for <br />a financial warranty release & bond reduction when all required reclamation tasks/phase have <br />been completed in accordance with the approved reclamation plan). Please respond. <br />6.4.19 EXHIBIT S -Permanent Man-made Structures <br />11. In conformance with Rule 6.4.19, please provide or indicate the status of the notarized <br />agreement & damage waiver from the Larimer County Engineering Department, LCR 901 <br />(County Line Road). <br />12. The Applicant has provided a notarized agreement & damage waiver from Weld County <br />