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Mining Plan Exhibit D <br />Site Description <br />The site lies on the north and south bank of the Colorado River immediately east of the town of <br />Rifle and just north of I-70. The portion of the site which lies to the north has been operating <br />as a DMG 112 permited operation since 1979 with some areas of mining occuring prior to <br />] 977(pre-law disturbances). The northern portion of the site (Chambers Pit) has been neazly <br />mined out. However, it will continue to be used as a processing and stockpiling area for the <br />Scott property expansion across the river. A major feature of the expansion area is lazge <br />oxbow left from the river. The oxbow area is a wetland and will be avoided. The site's current <br />land exists as riparian, wetland, and irrigated field. A house and outbuildings also are on the <br />property. These may be moved prior to mining in Mining Area 3. To the west of the property <br />lies a narrow strip of land owned by CDOT. The CDOT site is too small to be developed. To <br />the east of the property lies the LaFazge Mamm Creek gravel operation. <br />Site Geology <br />The site contains Pleistocene age gravels with a bedrock of Wasatch Formation shale and <br />sandstone. The oxbow was once an active channel of the river, but due to deposition has been <br />naturally cut off from the current river channel. The gravel depth is expected to be 25 feet. <br />The gravel has very little fines and is very permeable. In the irrigated fields up to 5 feet of <br />overburden is expected. The topsoil in this azea is also thicker than the riparian areas. The <br />topsoil is expected to be 3 inches to over 1 foot in thickness. The area inside the oxbow is <br />expected to have very little overburden and slightly less topsoil. Average topsoil and <br />overburden depths can be seen in the Mining Area Volumes table. The water table level is <br />expected to be around 5300'-5311' in elevation. <br />Pre-Mining Work <br />Pre-mining activities for the Scott Expansion will consist of infrastructure installation, <br />sediment pond construction, topsoil and overburden stripping, and isolation berm construction. <br />The berm will be 2 feet tall with 2H:1 V slopes and will be constructed with overburden or <br />topsoil. These activities will take place in and around Mining Area 1-Phase 1 prior to mining. <br />Future mining areas will be prepared in a similar fashion. <br />One bridge and a suspended conveyor will be installed as part of the site. The bridge will be <br />used for truck traffic across wetland areas. It will be semi-portable and built from rail flatcars. <br />For the span two cars will be bolted together to provide sufficent bridge deck width. Precast <br />concrete blocks will be used for footings. When mining is complete the bridge will be <br />removed. The conveyor will be used to transfer gravel from the south side of the river to the <br />existing facilites at the Chambers Pit. The conveyor river crossing will be designed by a <br />licensed civil or structural engineer. The design will require that the conveyor be completely <br />enclosed. Both of these structures can be seen on the Mine Plan Maps C-2 and C-3. <br />4/26/04 Page D-t <br />