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Rule 6.4.5 Exhibit E- Reclamation Plan 8. The applicant proposes to reclaim the site as a clay lined water storage reservoir. Enclosed, please find a copy of the Division's guideline titled, "Guide to Specification Prepazation for Slurry Walls and Clay Liners as a Component of a Colorado Mined Land Reclamation Permit." As noted in this guideline, operators may choose the option to bond for 100% installation or replacement cost of a slurry wall or pit liner or may select a regulated construction option and become eligible fora 20% installation or replacement bond. The guideline contains information that must be submitted by [he applicant to be eligible for the 20% bonding option. Please inform the Division if the applicant intends to bond for 100% of the clay liner, or will provide the necessary information for the 20% bonding option. 9. The applicant proposes a 6" topsoil replacement depth on the reclaimed shoreline of the pit (approximately 3 acres in size). Due to the nature of the natural topsoil depths as noted in the soils portion of the application, the Division believes a more appropriate replacement depth to be 18" There appears to be more than enough topsoil available to achieve an 18" replacement depth. Please address accordingly. 10. The applicant states that mulch will be applied during reclamation. Please state the type and quantity of mulch to be used. 1 1. Please specify the season for revegetation of the site as required by Rule 6.4.5(f)(ii). 12. The applicant proposes a seed mixture containing Western Wheatgrass, Sideoats Grama and Blue Grama. These species do well in a dry rangeland environment. The Division suggests that the applicant include a few other species that adapt well to the riparian transition such as Streambank \r/heatgrass and Slender Wheatgrass. Please address accordingly. Rule 6.4.7 Exhibit G- Water Information 13. Rule 6.4.7(3) requires [ha[ [he applicant provide an estimate of the project water requirements including flow rates and annual volumes for the development; mining, and reclamation phases of the operation. This would include volumes of evaporative loss expected during maximum pit disturbance as well as during final reclamation. Please address. 14. In conformance with Rule 6.4.7(4), the applicant will need to clarify the water rights currently held by the applicant that will be available to supply the operational needs identified in the previous question. 15. As required by Rule 6.4.7(b), please identify all known aquifers that may be directly or indirectly affected by the proposed mining and reclamation activities at the 124 Estates mine operation. The applicant should also characterize the geology and depths of the aquifers as well as pertinent aquifer characteristics, if known. 16. The applicant states on Page 16 that dewa[ering may temporarily lower adjacent ground water levels during initial phases of mining. In accordance with Rule 6.4.7(2)(b), the Division requests that the applicant identify and characterize the aquifer to be mined in or through. The Division also requests that the applicant define or predict the cone of depression expected for any areas to be dewatered and dry mined during the life of the operation. The cone of depression assessment should define, at a minitnum, the horizontal and vertical extent of drawdown expected. If during the assessment, the applicant determines that a drawdown will occur offsite that may impact a current groundwater user, the applicant should explain any mitigation measures to be implemented and trigger points that would put mitigation measures into effect. 17. The applicant states that 60-acre feet of standing water must be discharged from the historic mining depression before mining activity can be initiated. Please describe how the rapid drawdown of the pit will impact the structural integrity of [he surrounding wells and surface water drainages.