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Colony Shale Oil Project, Colorado MLRB Permit M-80-047 December 13, 3006 20D6 Affected Area Status Summary and Request for Reduction in Affectetl Acreage 1.0 Introduction This report was prepared in response to questions raised by Colorado Division of Reclamation, Mining and Safety (DBMS) staff during a scheduled site inspection on July 19, 2006. This report addresses certain areas within the current total affected acreage that ExxonMobil trelieves should qualify as completely reclaimed in accordance with the approved reclamation plan. It also addresses certain areas includetl within the total affected acreage for which the post-mining land use should be changed, or simply clarified in some cases, to reflect the expected future use of these areas. to all of these latter cases, the current site condition is the same as it would be in the future land use. Accordingly, the two categories described above are lands being requested for removal from the affected area. 2.0 Background The total permitted acreage is 6,778 acres. Of this 1,127 acres were listed as disturbed as of the 1982 Interim Site Plan (ISP), which was treated as an amendment to the permit. By the year 2000 the total affected area was reported as 1,134 acres, but it now appears that a few acres related to ongoing construction by pipeline companies near Colony's roadway easement, but not within Colony permitted lands, may have been inappropriately counted. The original 1,127 disturbed acres was increased by 3 acres in 1987 with the addition of the ESR Test Plots site south of the Plant Site Area 18. This area is not included in the 1982 ISP amendment, which was based on the 1982 Site Disturbance Inventory. Later, in 2000, approximately 1 acre of new access road disturbance was required near the southern Colony property line to provide access while natural gas pipeline construction by others blocked Colony's road easement on Unocal (now Encana) property. These additional 4 acres since 1982 bring the actual disturbed acreage total to 1,131 acres. Since neither of these two late additions is planned for release in this submittal, discussion in this report will continue to steward to the original 1,127 acres described in the 1982 ISP. Of the original 1,127 disturbed acres described in the 1982 ISP, 110 acres were described in that submittal as already in their final reclaimed form as of completion of their Construction. These included: 76 acres of near vertical rock cut cliff faces associated with the Plant Access Road (38), Mine bench(14) and Firebreak Road (1}, and rockfill faces such as the Mine Bench face (11), the Plant Site's South Valley Fill (6), and the Switchyard Fill Face (6) • 23 acres of steep talus slope disturbance associated with the pre-permit Pilot Mine, and 11 acres of miscellaneous small areas where reclamation was completed upon completion of construction. Although no additional reclamation efforts or construction activity was planned for any of these areas, the operator saw no pressing need to claim them as completed or to start the process of removing them from the affected area inventory. In addition to the above described finished 110 acres, by year end 1984 another 281 acres had been reclaimed by revegetation, essentially as proposed in the ISP except for 14 acres that were not reclaimed but were instead stabilized. Although the majority of these 281 acres were too steep to allow spreading of topsoil, Colony believed these could nevertheless be stabilized by revegetation. This situation is alluded to in the original 1980 permit application (Exhibit E, p. E-46, E~8). Two large such additions to this category, totaling 66 acres, occurred in 1984, described as follows: • 3d acres of side slopes along the Dam Access Road (Area 8a), • a large 32 acre fill slope below Davis Falls that was regraded and seeded in 1984, concurrent with hauling material back to the Mine Bench to backfill the abandoned primary crusher pit'1. 1) The large gyratory primary crusher concept had been abandoned in summer of 1982 in favor of recently proven inlnine feeder breakers. The primary crusher pit excavation that hatl been opened in 1981 to enable construction and installation of this facil'Ry was no longer needed, and the material that had been excavated was n:turnetl to the crusher pft and placed as a controlled compacted fill in 1984, allowing for final grading of the remaining material below Davis Falls.