2012-02-28_REVISION - M1980244 (81)

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ASSUMPTIONS and PROCEDURES 5- Assumptions CRIPPLE CREEK & VICTOR (CC &V) GOLD MINING COMPANY MINE LIFE EXTENSION 2 MLE2 RECLAMATION COST ESTIMATE 1 Drawings & Autocad files of facilities were provided by CC &V staff and Downloaded from the CCV FTP Site. The processing of those drawings was perfomed as follows: a. The End -of- Mining configuration, a.k.a. Post - Mining- Topography or PMT, was obtained from the 2025 AutoCAD Drawing and checked against a pdf file overlay to ensure that it was correct. The latest version for 2025 was actually a Proposed 2025 version that matched the pdf file 2023- 2025.pdf. There were minor modifications made to that file until a reasonable earthwork balance was obtained for all of the mining areas - 1) it was assumed that WHEX would be totally backfilled to match the final reclamation configuration, though the 2025 map showed an unfilled Mine Area. That was changed. 2) The top of SGOSA was scalped by an amount equal to the amount filled in WHEX so that the two actions balanced each other. The adjusted configuration is plotted on SA Drawing No. 7. b. The Final Reclamation or Closure configuration is also called the Final Surface Contour or FSC on the drawings. The latest version of the F! map was used, but with one modification. The nose of the hillside at ECME -Wild Horse was filled in on the mining map (Item 1 a above). Accordingly, the nose was digitally filled in for the FSC arrangement. The adjusted configuration on which the estimate is based is plotted on SA Drawing No. 8 c. TIN surfaces were assembled for each Reclamation Area and for the PMT and FSC configurations. The earthwork balance (i.e. the necessary cut/fill to move from End -of -Mine to Closure) was digitally determined using AutoCAD Land Development Desktop. The amount of Cut or Fill for 100 foot grids of each reclamation area are plotted on SA Drawing No. 9. Each reclamation area was scanned by AutoCAD in N -S and E -W directions, providing a Mass Ordinate and cumulative cut/fill balance. That data was transferred to an EXCEL spreadsheet wherein the centroid of the Cut (weighted by departure and volume) and the centroid of Fill was determined. The average haul distance for that area can be approximated by the distance between those coordinate points, shown on Drawing No. 9. d. Areas that will be planted with trees include North and East Facing slopes. Those areas were delimited on the drawing and the surface area was extracted. The results are shown on SA Drawing No. 10. High -wall areas that are to be fenced are also shown on that drawing. e. The Growth Media Drawing (C4b) provided by CC &V was overlaid onto the reclamation model so that the haul distances could be measured. 2 Colorado Rule 6 section 6.34(2) requires accounting for the costs for reclamation ath the point of maximum disturbance. With one exception, that will occur at the End -of- Mining. The exception is for WHEX Northeast Mine Area that will be mined out in 2018 and backfilled. Grassy Valley drainage will be reconstructed at that time, rather than at the end of mining. 3 No salvage value for equipment, buildings, or tanks has been figured into the reclamation cost model. 4 Trees will be planted on reclaimed slopes that are east or north - facing in aspect. 5 It has been assumed that no liming will be required to enhance the revegetation success. 7 The present model assumes there will be no off -load storage of leach material 9 The cost for chemical closure of the VLF was estimated in the same manner asin previous DRMS Estimates. Hydrogen peroxide wash will be performed followedafter rinsing with two (2) pore volumes of water. 10 The costs are based on information obtained from Wagner Equipment (rental rates), Means Construction Estimating manual, Colorado Dept. of Labor Statistics, and Escalated Cost data from the US Commerce websites. Other site - specific costs have been provided by suppliers to CCV and /or historical experience. 19 Contractor Performance Bond - Included at 1% per DRMS requirements. 20 Contractors Overhead and Profit- Included at 5% per DRMS requirements. 21 Public Liability Costs - Included at 1.55% per DRMS requirements. 22 Contingency - A contingency allowance of 10 percent is believed to be adequate and appropriate for this estimate. That's because the substantial percentage of costs are attributable to Earthwork and Growth Media placement. The calculation of those quantities is relatively fixed for growth media (disturbed area times average depth), and the quantities of Earthwork have been calculated in a conservative manner such that the quantities are not likely to be exceeded by significant amounts.