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The zone to be mined is a 40 foot vertical section located 20 feet above and 20 feet <br />below the mahogany marker. The Mahogany Marker is a visually identifiable 6 inch thick <br />layer of volcanic ash which is continuous throughout the Green River Oil Shale <br />Formation and is used as a mining marker to maintain the proper mining horizon. The <br />marker is exposed at the mine site and will be used to maintain the mining interval as <br />excavation progresses. Overburden covering the mine zone ranges from 10 to 60 feet in <br />depth. <br />The 5 acre mine site is approximately 275 feet in width and 800 feet in length. The <br />existing 16 foot wide unpaved access road enters the mine site at a point on the <br />southwest boundary approximately 400 feet northwest of the southeastern boundary <br />(neap E1). The southeastern 1.75 acres of the 5 acre site have been previously disturbed <br />and the southeastern 1 acre of the disturbed portion of the site will be prepared for <br />reclamation as one of the first activities of the mining operation. Broken rock on the <br />disturbed 1.75 acre site will be used to re- contour the southern .55 acre area to an <br />approximately 2H:1V slope before application of top soil and seeding. The portion of the <br />existing drainage within the previously disturbed area will be cleared of rock and two 48 <br />inch diameter by 35 foot in length culverts which are sized to handle flow volumes from <br />a 100 year storm event (see attached Drainage Report (100 Year Flood)) will be placed in the <br />drainage to create a temporary crossing for use during the mining operations and will be <br />removed at the end of final reclamation. The mining operation will be conducted in a <br />northwesterly direction on the remaining 3.25 acres of the affected land. <br />All drilling operations will be with air or hydraulic powered equipment and the only water <br />usage will be for dust control. All water requirements will be met by trucking water to the <br />site from properly augmented commercial water supply sources. There will be no <br />ponding of water on site, no ground water will be encountered or disturbed so no injury <br />to water rights will occur. <br />The mining operation will utilize a track mounted hydraulic excavator to remove the <br />woody vegetation and the approximately 6 inches of channery loam top soil from new <br />undisturbed areas to be mined. Beneath the shallow layer of soil is low grade oil shale <br />rock overburden which extends downward to the richer mining zone. The removal of the <br />low grade shale above the mining zone will be accomplished using a track mounted <br />hydraulic impact breaker and excavator to break and remove the overburden. A rubber <br />tired front end loader will be used to transport and place overburden into the recently <br />mined area and or to the back fill area to the southeast of the mining advance. The <br />slopes adjacent to the mining operation will be benched to minimize vertical high walls <br />and will be scaled with an excavator to eliminate loose rock. The expanded volume of <br />rock created when the overburden is broken will fill a void equal to the area cleared of <br />overburden and the area mined for production during each mining cycle. <br />2 <br />