2019-12-13_REVISION - M1980244 (68)

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NEWMONT GOLDCORP. standard water rinsing cycles and one H2O2 rinsing cycle over an approximate six-year period. The rinsing procedure will employ a rinse -rest strategy as previously approved. The VLFs will be rinsed in segments with portions being actively rinsed while other areas are allowed to "rest." Rinse water and H2O2 will be circulated using the VLF pumping systems at a pumping rate of approximately 15,000 gallons per minute. Rinsing criteria previously approved for the VLFs is an average concentration weak acid dissociable cyanide (CNwAo) of 0.2 mg/L in the rinse water from meteoric water mobility testing on representative sampling of the spent ore, or in return flows derived from the neutralized ore, or both. A four-year monitoring period will follow the rinsing to demonstrate compliance with the standard. Physical reclamation of the VLFs will be completed in approximately 2 -years and will start concurrent with the monitoring period. Upon achieving the CNwAo rinsing criteria, the VLF liner systems will be breached in the same manner as previously approved. The liner will be perforated to prevent excessive accumulation of stormwater infiltration in the neutralized ore behind the toe berms and to move meteoric drain down stormwater into the underlying diatreme rock. It is anticipated that a drill rig will be used to drill from the surface of the ore on the VLFs through the synthetic and clay liners into the closure drains and underdrains, where appropriate. Holes will be drilled to puncture the liner above these features installed at several locations beneath the PSSAs. This will allow conveyance of post - reclamation precipitation through the material on the VLFs and into the underlying diatreme. Following the achievement of the CNwAo removal criteria for both VLFs and following the breaching of the liner systems (as discussed above), all down -gradient appurtenances will be reclaimed as follows. At both VLFs the pipes, pumps and other structures will be removed from the underdrain collection systems. The concrete pump -back vault side walls and bottom will be broken up, followed by burial onsite with surrounding fill material. Ponds will be backfilled with material and re-contoured. The entire area will then be graded to blend with the surrounding topography, followed by reclamation of the sites. The slopes of the VLFs will be re-contoured to an overall slope of approximately 2.5H:1 V. Portions of the benches created during operations will be retained, as appropriate, for geotechnical and erosional stability. The topography shown on Drawing F-1 and the financial warranty calculations presented in Exhibit L have been developed based on an overall 2.5H:1 V slope criterion. Cripple Creek & Victor Gold Mining Company Cresson Project Amendment 13 13 Exhibit E