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lake to the north. Based on the results of the modeling, in order to completely dewater both pits the estimated discharge rate is approximately 1,127 gpm and 1,141 gpm for the winter and summer periods respectively. Dischazging this water into the adjacent lake would help maintain constant water level in the lake and would also serve to stabilize the surrounding groundwater elevations by effectively rechazging the surrounding aquifer. This would help protect the two wells located to the north and northeast of the site." Although this is a potentially effecfive solution to minimize impacts to the prevailing hydrologic balance of the azea surrounding the affected land, the report does not adequately identify how groundwater levels would differ between this method as opposed to conveying the dischazge water to the St. Vrain River. The predicted drawdown map included in the report presumably represents the conditions expected if dischazge water is conveyed to the St. Vrain River. The Applicant should submit a map reflecting the results of the model using the adjacent lake as the dischazge point for water removed from the pit. Additonally, although the report identifies this method as a practical mitigation alternative, it does not state that this is the method the operator will use in mining the site and indicates that the Operator may opt for either dischazge method. If the Operator will use the lake as a dischazge point for the water, this must be specified. S. The report concludes that the maximum drawdown at a distance of 600 feet from the site is 13 feet during mining. Additionally, the model predicts that groundwater level in the well south of the site could drop as much as 7 feet. The Division has determined that the Operator is not proposing to take adequate measures to minimize impacts the prevailing hydrologic balance of the azea surrounding the affected land, as required in section 3.1.6 of the Construction Materials Rules and Regulations. Additionally, the report does not identify a specific monitoring plan for the site or a specific mitigation plan for the site including trigger points that would prompt mitigation measures. A full monitoring plan and mitigation plan, specifically outlining monitoring frequencies and mitigation measures that will be incorporated, needs to be submitted with the permit application and must be approved by the Division prior to approval of the permit. Rule 6.4.12 Exhibit L- Reclamation Costs 9. The Division will estimate a cost to reclaim the site based on the information submitted by Lafazge in the forthcoming adequacy response. Rule 6.4.14 Exhibit N- Source of Legal Riglmt to Enter 10. As previously stated, please provide documentation for the legal right to enter the easement associated with the Smith and Emmons Ditch for purposes of mining and reclamafion at the Duckworth Pit. Tkmis must be submitted to the Division prior to approval of the application. 11. As previously stated, please provide documentation for the legal right to enter the easement associated with the conveyor structure proposed over Weld County Road 20%2. Rule 6.4.19 Exhibit S-Permanent Man-Made Structures 12. Lafazge states that they will maintain an offset equal to 3 times the pit depth, or 60 all structures....this offset will include an additional 50-foot buffer for waterways, Idaho Creek and Smith & Emmons Ditch. Please clarify if Lafarge intends to maintain an off set distance of 110 feet (60 feet plus the aclditiona150 feet noted above) from Idaho Creek