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The Colorado State University has some experimental plots in adjacent <br />lands which will not be affected by the proposed action. <br />1•lAT E R <br />The topographic surface of this area lies within the upper reaches of <br />the Pine Gulch drainage basin. The watershed is steep-sided (with <br />slopes greater than 50%), has intermittent streamflow, and has a den- <br />dritic drainage pattern. The 100-year stream flow rate of Pine Gulch, <br />on the lease site, is 120 cfs., with an assumed velocity of 4-5 .ft/sec. <br />Flow rate was calculated from "Manual for Estimating Flood Characteristics <br />of Natural Flow Streams in Colorado", Colorado Water Conservation Board, <br />1976. <br />The application area is not in a major ground water recharge area. <br />Because the mine will be located approximately 40 feet above the piezo- <br />metric surface, static water level, there is no indication that the <br />aquifer will be affected by mining operations. <br />VEGETATION <br />The vegetation of the general area consists primarily of dense shrub- <br />lands dominated by a variety of shrub species. 'The most prominent <br />shrubs include Gambles Oak (Quercus aambelii), mountain mahogany (Cercocarpus <br />montanus), and Utah serviceberry Ame anchier utahensis). Other important <br />shrubs include antelope bitterbrush Purshia tridentata), squaw-apple <br />(Pe raphyllum ramosissimum), and green ephedra E hedra viridis). Scattered <br />pinyon pine (Pinus edulis) and Utah juniper (Junipers utahensis) occur <br />on the more xeric sites, while scattered ponderosa pine Ptnus ponderosa) <br />and Douglas fir (Pseudotsu a menziesii) occur on the more mesic sites. <br />Important species to t e understory include bluegrass (Poa spy.), western <br />wheatgrass (A ro ron smithii), bottlebrush squirreltail TSitanion <br />h sy trix_), yucca Yucca baccata) and milkvetch (Astragalus ~- <br />The mesa top area has undergone various vegetation treatments including <br />chaining, burning, and herbicide application. A grassland meadow dominated <br />by wildrye (Elymus gip.) has been established through seeding on a <br />portion of the mesa top. <br />There are no known endangered or threatened plant species in this area. <br /> <br /> <br />15 <br />