2003-03-31_REVISION - M1977344 (2)

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Division of Minerals and Geology March 31, 2003 Page 10 of 17 Holcim plants. Buildings and structures will be demolished and all steel will be salvaged for scrap or other uses. Pavement and concrete structures will be broken down and buried as fill for final reclamation at the site or in the quarry area. Once all structures including the railway have been removed, the area will be graded and contoured, then topsoiled and seeded for the end use as range land. Exhibit F-Reclamation Plan Man Item No. 24 DMG: According to the contour lines on your map, the steepest reclamation grades are proposed to be 2h:ly; whereas, your reclamation plan indicates that the outer edges of the backfilled pit are proposed to be left at the angle of repose or about 1.3:Iv. Please clam this discrepancy. 77te presently approved maximum reclamation slope in your permit is 3h: Iv. This is the slope the Division recommends and a slope that will help ensure that reclamation efforts are successful. Your reclamation plan map contours must agree with the slopes stated in your reclamation plan. Please make the necessary changes accordingly (see Rule 6 Section 4.6 (a)). Response: Please see revised Figured F-1. Item No. 25 DMG: Please show on your map the proposed topography of the plant reclamation area. Response: Please see revised Figured F-1. Exhibit G-Water Information Item No. 26 DMG.• What is the elevation of the water table in the area of mining cuts 3-18? Given the information reported in Table G-1 and thefact that Holcim proposes to divert and mine a portion of the channel in this area, even shallower ground water expressing itself as surface water can be anticipated. How does Holcim plan to address the water which will more than likely be impounded at lower elevations, during mining and reclamation? Response: Exploration conducted by Holcim in the Bear Creek watershed has indicated that no water table is present above the top of the Codell sandstone. Consistent with what has been observed to the west side of the fault, discontinuous, perched, saturated zones are believed to exist in the overlying limestone and shale formations. The first unconfined aquifer is located in the underlying Codell sandstone. This is consistent with Holcim's experience in the west side of Cuts 2 and 3 in lower Bear Creek, where mining has progressed to the top of the Translime layer of limestone, and no saturated conditions have been observed. Any impounded water in the quarry will be utilized for mining operations (e.g. dust abatement). In the event that impounded Hoictm Response to Amendment Adequacy Review.doc