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cut/fill whose profile azeas were derived from the included volume graphic, and whose calculations aze detailed on page and 9. Volumes for each area aze shown. The balance of grading for Areas A and B, and for that matter, the re-extraction of C, assumes grading is concurrent to 3H:1 V slopes from 10 feet below to 5 feet above the anticipated final water level of the completed basins, with the exception of an 800 foot advancing wall. Like the ponded Area C, this line assumes the material will be met by a cut of in-place material from above, and a fill from in-place shale cut from below. This 800 foot length of this determination may prove too conservative and could be doubled for purposes of this determination. Regazdless, due to the nature of cut and fill of shale, in-place material, and waste stockpiles, it is not practical to distinguish the volumes beyond that shown, except to say that the use of stockpiled material is not anticipated. Portions of the unused waste fines and materials surrounding Area C pond may ultimately be utilized in the backfilling of Area D. Since the grading of Area D is already provided for, filling costs are not necessary for this determination beyond that already provided for. 7. In conformance with Rule 6.4.4, please clazify the current or planned volume, whichever is greater, of stockpiled topsoil that will needed for use in final reclamation, and provide the average push/haul distance to move the stockpiles topsoil to its final location. Please clarify. These determinations were fully detailed on pages 11 & 12 under Exhibit L -Soil Demand and Re-soiling of Affected Lands. The average push distance utilized in the determination as stated is 600 feet and utilizes the soil from existing stockpiles shown on Exhibit C -Mine Plan Map, and detailed by volume per stockpile as identified, under Addendum B to Exhibit L: Stockpile Measurements. 8. In conformance with Rule 6.4.4, please clazify the following lengths of pit wall and/or lake shoreline (in linear feet) to be backfilled and graded to reclamation contours (3:1,4:1,5:1, etc.): a) # LF of pit wall already at final reclamation contours, b) # LF of existing pit wall at 1: 1, 0.5: 1 or steeper contours, c) # LF of future pit wall to be exposed from now (January 6,2003) until such time that the Durham pit has been completely mined. Please provide. Exhibit L specifies a 1:1 slope surrounding Area C Pond Shorelines, a neaz vertical slope for the approximations of grading Area D and the Advancing Pit Walls, with concurrency of slopes to 3H:1 V for mine perimeters. A volume gaphic was used to determine profile volumes used in cut, fill, and cut/fill determinations, as provided under Exhibit L. 9. In conjunction with Item 8 above and in conformance with Rule 6.4.4, please clarify the maximum number of linear feet of high wall to be exposed at anyone time throughout the remainder of the operation. (VCI has proposed nearly 8001inear feet of advancing pit wall for the active operations in Tract A, and subsequent operations). As detailed for Areas A, B, C, and D under Exhibit L -Reclamation Casts, the perimeter and exposure of pit walls, and pit wall profiles is detailed for each area. For purposes of creating a conservative estimate to the benefit of the Division, vertical walls were assumed for Area D and the Advancing Pit Wall, and 1 H:I V for walls below the water level of the existing pond under Area C. If it would please the Division, the 800 foot linear wall as proposed could be doubled to account for some lag in time for concurrency of establishing 3H:1 V finished slopes along the perimeter of the Active Area being extracted. Varra Companies, Inc. M1978-056 Durham Sand & Gravel Pit - 2003 Amendment - Monday 26 Apri12004 reply to correspondence from the Colorado Division of Minerals and Geology of 6 January 2004.