2016-09-14_REVISION - M1980244 (2)

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(MLE2). Figure 3 shows the area of disturbance associated with this proposed TR and the MLE2 delineated wetlands. Access Road and Parking Lot Construction The seven acres of access road will be approximately 1500 feet in length, 50 feet wide, 30 feet above the native material on the east side, and 50 feet above the native material on the west side. The six acres of parking lot will be approximately 350 feet in width and 800 feet in length. The construction of this parking lot will not interfere with the already constructed storm water collection pond EMP-16. The amount of material required to place for structural fill to create the desired road alignment will be approximately 140,000 tons. This material will be run-of-mine material blasted to a nominal size of 24" minus, with preference given to material with finer particle size fractions. The access road will be constructed in lifts using existing mine equipment. Parking lot construction will use the same run of mine fill to create a level surface which will then be compacted and covered with gravel. Finally, the necessary fences, lighting, parking ditches, etc. will be installed. Figure 4 shows the orientation of fill placement for the access road. Storm Water Detention and Catchment Area As part of the construction of the North Grassy Valley access road a storm water detention basin will be included on the north side of the access road. After examining the topography above the access road, a surface water catchment area of approximately 66 acres has been defined and is shown in Figure 5. Permit No. M-1980-244 - Amendment 10 — MLE2 appendix 12 section 1 addresses storm water hydrology for the mine site. This section specifies the volume for storm water catchment will be twice a 10 year 24 hour storm event (2.7" of precipitation). This section also specifies the Soil Conservation Service (SCS) curve number method to determine the runoff volume for various areas of the mine site. For areas considered to be "Grassed existing areas and closure areas reclaimed with growth media and revegetation methods..." a curve number of 71 is specified. Using the SCS method specified and the catchment area defined (66 acres) a total runoff volume of 1.065 million gallons is calculated, necessitating a storm catchment capacity of 2.13 million gallons. The location of the storm water detention basin is shown in Figure 5. Parking Lot Contour and Drainage As explained above, the access to the parking lot will be constructed adjacent to the WHEX Pit. This facility will be constructed with a berm around the perimeter and will be contoured to prevent sedimentation of the wetlands as well as to route storm water run-off into the detention pond EMP-16 immediately to the south east of the parking lot. Figure 6 shows the anticipated contour layout for the parking lot. Access Road and Parking Lot Warranty Estimate CC&V used Newmont's Standard Reclamation Cost Estimator (SRCE) to estimate reclamation costs for this TR. Table 1 below demonstrates how unit and total costs were calculated. The project will increase the reclamation costs by a total of$166,647.00.