2007-08-17_PERMIT FILE - C1981035 (21)

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There are no active faults adjacent to or on the proposed • modification area (Zapp, 1949). No other geologic hazards are known to exist. No known fossils of significance have been found on or near the modification area. The Mesa Verde Group yields sparse faunas of both marine and non-marine elements. No study exists with specific reference to the botanical fossils related to the Menefee coals nor on the non-marine invertebrates on the associated units (Fischer, 1981). WATER The topographic surface of this area lies within the mid- section of the Pine Gulch drainage basin. The watershed is steep-sided (with slopes greater than 50~), has intermittent stream flow, and has a dendritic drainage pattern. The 100- year stream flow rate of Pine Gulch is 120 cfs., with an assumed velocity of 4-5 ft/sec. Flow rate was calculated from "Manual For Estimating Flood Characteristics of Natural Flow Streams in Colorado", Colorado Water Conservation Board, 1976. The proposed modification area is not in a major ground water recharge area. Because mining activity in coal bed 1 will be occurring approximately 40 feet above the piezometric surface, which is static water level, there is no indication that the • aquifer will be affected by mining operations. VEGETATION - The general area consists primarily of pasture and mountain shrub type vegetation along with pinon-juniper. The most prominent shrubs include Gambel oak (Ouercus aambelii), Mountain mahogany (Cercocarpus montanus), and Utah serviceberry (Amelanchier utahensis). Other important shrubs include Antelope bitterbrush (Purshia tridentata), Squaw-apple (Perat~hyllum ramosissimum}, and Green ephedra (EAhedra viridis). Scattered pinon pine (Pinus edulis) and Utah juniper (Juninerus utahensis} occur on the more xeric sites, while scattered ponderosa pine (Pinus ponderosa) and Douglas fir (Pseudotsuaa menziesii) occur on the more mesic sites. Important species in tl.e under story include bluegrass (Poa Spp.), western wheatgrass (Aaropvron smithii), bottlebrush squirreltail (Sitanion hvstrix}, yucca (Yucca baccata), and milkvetch (Astraaalus Spp.). The mesa tops within the existing leases as well as the proposed modification areas have undergone various vegetation treatments including chaining, burning, and herbicide application. A grassland meadow dominated by wildrye (Elvmus Spp.) has been established through seeding on a portion of the mesa top. i 10