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Prior to placing the sand and gravel fill materials, we recotttrttend that all of [he topsoil materials be removed and the exposed subgrade soils be scazified to a minimum depth of 6 inches and be recompacted to at least 92% of the maximum modified Proctor density determined in accordance with ASTM D1557. An alternative to removing the topsoil materials would be to place a layer of geotextile stabilization fabric, such as Mirafi 600X of an equivalent product, over the existing topsoil surface and then place a minimum of 2 feet of sand and gravel fill materials over the fabric. If this method is opted for, the amount of sands and gravels required in the roadway section may need to be increased by at least 12 inches, depending on the depth and condition of the topsoil materials. The sand and gravel fill materials should be placed and compacted in 6 to 8 inch lifts to at least 95% of the maximum modified Proctor density. The haul road fill section should be constructed to a 1.5(horizontal) • 1(venical) or flatter slope configuration. Based on our experience with similar projects and our conversations with Tom Knowlton of the Public Service Company, we recommend that a minimum of 5 feet of compacted embankment fill be placed over the existing ground surface in the limits of the existing gas line easement. The upper 2 feet of fill materials placed in the embankment should consist of the sands and gravels, whereas, the deeper fill materials can consist of the overburden clays. The clay and/or sand and gravel fill materials placed in the roadway embankment should compacted [o at least 95 % of the maximum modified Proctor density. Based on our experience with similar projects and the subsurface conditions encountered at this site, we believe that the construction and use of the proposed haul roads will not have a detrimental affect on the existing gas line or fencelines, as long as the roadways are constructed in accordance with the above recommendations and properly maintained. SITE RECLAMATION The following recommendations should be followed to reduce the potential off-site or on-site impacts related to the reclamation of the site from a geotechnical standpoint. 1) Positive surface drainage features should be constructed around the perimeter of the mined areas so that the surface runoff is directed away from the top of the cut and the reclaimed fill slopes. Surface drainage may be taken across Ute reclaimed surfaces as long as the flows are confined to properly designed drainageways. 2) The topsoil removed from the excavations and stockpiled at the site should be spread out evenly across the finished slopes shortly after they have reached the desired grades. Based on a final slope lab No. 98.351M NoMwest Colorado Cortculrants, Inc. Page 7