2023-07-27_REVISION - C1981038 (10)

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coal mine fire. The applicant proposed to upgrade an existing public access road to serve as a coal haul road to the proposed West Mine portal bench, which was to be constructed by a balanced cut and fill method. The portal bench fill included a 130-foot maximum height terraced earthen fill constructed across East Roatcap Creek. Maximum inter-terrace facial slopes did not exceed a 2.5:1 (horizontal to vertical) slope gradient. A 48-inch concrete culvert was installed beneath the cross valley fill to accommodate the 100-year flow of the East Roatcap Creek. The permit revision application included geotechnical specifications, documented in an appendix of Volume 6 of the PAP, prepared by Golder and Associates. This appendix presents the results of geotechnical investigations, stability analyses, and detailed engineering designs for the west portal bench cut and fill and the accompanying upgraded haul road. The stability analyses were based upon projected slope configurations and material mechanical properties obtained from material sampling and laboratory analyses. Stability analyses were completed for both the operational and reclaimed configurations of the west portal facility area. Reclamation of the West Mine began in 2000 with complete structural demolition and removal at the West Mine portal bench. The three portal adits were backfilled with compacted, non-combustible material. Structural demolition at the West Mine fan area was also accomplished. Backfilling and grading of the West Mine portal bench began in 2000 as well. However, because of site constraints, complete backfilling and grading was only possible for the upper portion of the site.When vegetation has been established on the upper portion, the East Roatcap Creek culvert will be removed and the lower portion will be backfilled and graded. BRL applied for, and received approval for, partial Phase I bond releases for reclamation work performed at the Bowie No. 1 West Mine (SL-02) and the Bowie No. 1 East Mine (SL-04). XI. Revegetation - Rule 4.15 Information pertaining to vegetation baseline may be found in the PAP, Section 2.04 of Volume 1, and in the Vegetation Appendix of Volume 9A. Information pertaining to the revegetation plan and vegetation success criteria may be found in the PAP, Section 2.05 of Volume 1, and in the Vegetation Appendix of Volume 9A. Disturbance at the Bowie No. 1 Mine began in late 1975. Currently,additional disturbances are not anticipated due to the cessation of mining. Initial disturbance occurred prior to any requirements for preparation of vegetation inventories;thus,portions of this mine site were not surveyed. However, as areas were proposed to be disturbed after the initial permit was issued, they were first inventoried. Several vegetation inventories have been completed to date at this mine site. The first inventory was conducted in 1977 and provided a brief qualitative description of the vegetation types to comply with the existing baseline requirements. With the enactment of the Colorado Surface Coal Mining Reclamation Act came more stringent baseline requirements. A second inventory for the two reference areas(pinon-juniper and mountain 33