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Colony Shale Oil Project, Colorado MLRB Permit M-80-047 December 13, 3006 2006 Affected Area Status Summary antl Request for Reduction in Affected Acreage 4.2 Resource Block Reclaimed Areas 4.2.1 Mine Bench This area consists of 56 acres, of which 27 acres are the flat surface of the mine bench and 4 acres are an access roadway along the west edge of the bench to the mine's vent portal site (A-groove road). The remaining 25 acres are comprised of 14 acres of finished vertical benched rock cuss on the east side of the bench and 11 acres of a 1.75:1 rockfill slope on the south face of the bench. (The vertical benched rock cuts on the west side of the Mine Bench are included within the Plant Access Road, Area 19C, and are discussed later). The approximate limits of the area are shown on Exhibit F-3, and post-mining topography (current topography} is shown on Exhibit F-4. The current condition of the areas is presented on Figures 24 (p. 21), 43 and 44 (p. 33). The 27 acre flat surface of the Mine Bench and the 4 acre A-groove Road remain active areas. The remaining 25 acres of cliff faces and the 1.75:1 sloping rockfill face were in their final form as of completion of construction, as described in Exhibit E of the original March 1980 permit application (p.E-49). Accordingly, 25 acres of Area 6 are requested for removal from the affected area on the basis that these meet the approved reclamation plan. 4.2.2 Upper Middle Fork (ISP Area 7) This area consists of 77 acres immediately around and upstream of the Middle Fork Dam, which was constructed in 1984. The approximate limits of the area are depicted on Exhibit F-3. The reservoir surtace is approximately 5 acres, and the affected land area around the reservoir is 72 acres. Post-mining reclamation plans consisted of reclaiming construction areas associated with the completed roller-compacted concrete (RCC) dam and reclaiming borcow areas opened up, but never used, for the originally designed earth and rockfill embankment dam design. Approximate post-mining topography is depicted on Exhibit Fem. Current conditions in this area are depicted in Figures 4 through 9 below. The possibility of the dam and reservoir becoming permanent post-mining water resource assets was clearly considered in the reclamation plan submitted with the original March 1980 permit application (Exhibit E, p. E-48). With respect to other construction related disturbance, this reclamation plan called for topsoil to be used in regraded areas where practical, and for other exposed valley slopes to be stabilized to the extent possible, recognizing that rock slopes would not be amenable to topsoiling. In Upper Middle Fork, the change to the RCC design in 1982 resulted in a greatly reduced construction disturbance impact. This disturbed area reduction occured because the volume of the concrete dam was about 20°k that of the previous embankment dam, and most of the aggregate needed for the concrete was already available in the form of marlstone existing on the Mine Bench Yz mile to the south. Areas that had been stripped of vegetation in preparation to open borrow sources had not yet been stripped of topsoil. Therefore, upon completion of construction of the concrete dam, all that was required in most of these areas was to re-seed the areas with the permanent seed mix approved for this site. Examples of this treatment are presented in Figures 8 and 9. Other areas that had already been opened to expose rock faces to become quarries for the rockfill portions of the previous embankment design were already in their final form with vertical rock faces. This area is visible in Figures 6 and 7, including the 2:1 regraded zone below the cliffs that was amenable to stabilization by permanent revegetation, which was done n 1986.