2008-09-17_REVISION - M1980244 (28)

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• g) Are there any other under ground workings other than those shown in the under ground workings map labeled A-120? The underground workings remediation typical details map A-270 only shows remediation for shallow shaft, open mines slot and open lateral. What about remediation plans for the Columbine and Squaw tunnels that will be underneath the southern extension of VLF Phase 5? Please explain. Response: As discussed in pages 14-16 of the Valley Leach Facility design report prepared by Smith Williams Consultants, Inc. included within the MLE Project Application as Appendix 8 within Volume V. A site reconnaissance of the underground mine workings within the Phase 5 VLF area, was conducted for the Phase IV and submitted within Amendment No. 8. As part of the Phase 5 VLF design effort, Smith Williams undertook additional detailed evaluations of the area. The primary activities that were completed included the following: • A detailed review of the available historical records, including the historical mining plans filed at CC&V and in the public record. • A review of the Phase IV VLF site reconnaissance and remediation. These data, combined with the experience gained during the construction of Phase IV, were used to develop the mine working remediation guidelines. The areas requiring remediation • have been initially identified from the available information. The Columbine and Squaw Tunnel addressed in the DBMS comment are considered "open laterals" as identified for stabilization on Drawing A-270 of the SWC Phase 5 VLF design report for remediation and will be appropriately addressed during construction. Remediation activities always involve further investigations to provide more detail on the type and extent of mine workings prior to remediation. Each feature observed on surface, and identified underground as potentially requiring remediation, will be re-assessed thoroughly again as part of the remediation process; and the final remediation requirements will be based on these re-assessments. V) Exhibit E - Reclamation Plan - Rule 6.4.5 A. The unlabeled topography map titled "Post Mining Topography for MLE Reclamation Facilities", corresponding to reclamation cost estimates does not have contour intervals corresponding to the contour lines and is also missing elevation numbers. The scale is the only thing labeled at 1 inch to 800 feet. Since the map was utilized to calculate the required warranty, including estimates of total material placement in the different overburden storage areas, backfill and grading, and haul distance costs, DRMS requests that the operator provide another map with the appropriate labels, such as the actual post mining topography with elevations and the 35 foot contour intervals utilized. The map also had a written disclaimer saying, "This map represents the approximate boundaries of facilities used for the reclamation cost estimates". Drawing C-4, Proposed Facilities Overburden and • Mines Cresson-Mine Life Extension, also has a similar disclaimer. Please remove all disclaimers from all the maps and narrative. As stated earlier, DRMS requires the worst case scenario for any operation, in order to calculate the required warranty to return the affected land to the approved post mining land use. If the current proposed plan is not the 14