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Exhibit C - Minino Plan <br />6. Please demonstrate that the ditch, slated to receive the significant discharge from this site, is <br />adequately sized and constructed to handle the significant volume and flow rate of the discharge, <br />especially at the location of the pipe discharge. If any structures are required to armour this ditch <br />or modify it for the discharge, these locations must be incorporated into the permit area through <br />an amendment of this application. <br />7. Topsoil piles should be constructed with sides no steeper than 3:1 to reduce erosion potential and <br />ihcrease potential for successful stabilization through vegetation establishment. <br />8. To avoid increasing selenium loading into the river, operations that result in increased oxidization <br />of the Mancos shale bedrock must be prevented. Please commit to conducting mining and <br />dewatering operations such that a minimum 1 foot of gravel is left in place over the bedrock, no <br />excavation into the Mancos shale occurs (except for the bridge support footers), and dewatering <br />is conducted in a manner that ensures groundwater continues to flow over the shale bedrock <br />during the mining operation. <br />9. The water information does not demonstrate that adequate water rights are held by the <br />landowner to cover evaporative loss during or after mining. Please commit to securing an <br />approved well permit, with a substitute water supply plan for the consumptive~losses proposed <br />during mining, before exposing groundwater at this site. <br />10. In the absence of an adjudicated water supply plan or substitute water supply plan, DMG must <br />include costs for backfilling the pit, to a point 2 feet above groundwater level, in the reclamation <br />cost estimate. <br />11. Minimum riprap size specified for the riverbank armoring project is 5 feet in the permit text and 4 <br />feet on the detail diagram. Please correct this discrepancy and submit a geotechnical <br />demonstration that the specified rock is adequate for use as riprap at this location and that <br />installation without a geotextile mat underlining will be adequate to stabilize this river bank under <br />the conditions expected. <br />Exhibit D - F2eclamation Plan <br />12. DMG believes reclamation liability for this operation is when phase 1 is mined with the outer <br />slopes backfilled to 3:1, phase 2 has been stripped of topsoil and overburden. In this scenario, <br />there is 800 feet of highwall to be backfilled, plus the phase 2 acreage to be covered, ripped <br />topsoiled and seeded. Please revise the permit text (regarding the maximum reclamation liability) <br />and reclamation cost estimate accordingly. <br />13. Please revise the reclamation plan and cost estimate to include a task for ripping, to a two foot <br />depth, all areas where topsoil is to be replaced. The ripping should tie performed immediately <br />prior to topsoil replacement. Additionally, the cost estimate will need to include a dewatering task <br />(phase 1). <br />14. The permit contains statements that the final pit slopes will be 3:1 and statements that the pit <br />slopes will be 3:1 to 5 feet below water level, and 2:1 below that. Please revise the permit text to <br />be consistent and indicate either that reclaimed pit slopes will be at a 3:1 grade to at least 10 feet <br />below water level, or that the pit slopes will be at a 3:1 grade from top to bottom. <br />