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<br />Proposed Decision and Findings of Compliance July 2018 <br />Permit Renewal No. 7 P a g e | 17 <br /> <br />Precipitation averages 18 inches annually on the property and runoff is limited. Flows in the <br />drainages are mainly in response to snow melt or intense thunderstorm events. <br /> <br />Water sampled from the drainages is quite hard, dominated by calcium and magnesium cations <br />and bicarbonate and sulfate anions. The relatively high alkalinity and pH of the system impedes <br />the solubility and transport of heavy cations, thus minimizing potential toxicity problems <br />associated with heavy metals or acid drainage. <br /> <br />Springs and seeps are abundant in the area, with 59 originally identified during an inventory <br />completed in 1985. A more recent inventory and study resulted in additional springs and seeps in <br />the South Taylor and Lower Wilson areas. Four springs were found to be perennial, two tributary <br />to Wilson Creek and two tributary to Good Spring Creek. The locations of all monitored springs <br />and seeps are shown on Maps 10A and 10B of the PAP. Spring and seep information is included <br />in Tables 2.05.6-1 and 2 in the PAP. <br /> <br />No alluvial valley floors (AVFs) exist within the area to be mined. However, the alluvial deposits <br />of Good Spring Creek, Wilson Creek, and lower Elkhorn Creek meet the geomorphic and irrigation <br />criteria of an AVF and are discussed in the Findings portion of this document (Section B, Item <br />XXII). <br /> <br />The Wilson Reservoir, from which water is drawn for mining activities, is an important fishery of <br />the area. The Wilson Reservoir was built in 1941 and is under the regulatory jurisdiction of the <br />Colorado Division of Water Resources. Except for a pumping station, the Wilson Reservoir is not <br />within the permit area, and is not a part of the Permit. The pumping station at the reservoir, and <br />the pipeline from the pumping station to the main areas of the Mine, are included in the Permit. <br />4.10 Vegetation <br /> <br />Baseline vegetation information is found in Section 2.04.10 of Volume 1, Map 4 and Exhibit 10 <br />of the PAP. Vegetation information associated with the Lower Wilson and South Taylor expansion <br />areas can be found in Section 2.04.10 of Volume 12, Exhibit 10 of Volume 13, and Maps 3, 4A, <br />and 4B of the PAP. Vegetation information for the Collom area is found in Section 2.04.10 of <br />Volume 15 and Map 4C of the PAP. Six vegetation communities and a small amount of cropland <br />exist within the Mine permit boundary. The major communities are sagebrush and mountain <br />shrub. Communities of lesser extent include a juniper community in the vicinity of Streeter <br />Mountain; aspen groves in the upper reaches of Streeter, Taylor and Wilson Creeks; a limited <br />riparian community along Good Spring, West Fork Good Spring, Wilson, and Taylor Creeks; and <br />a small western wheatgrass community in the southern portion of the permit area. <br /> <br />The sagebrush community occurs throughout the permit area on all elevations, slopes and soils. <br />The community has developed wherever soil moisture retention and soil depth have become <br />limiting to other vegetation communities. Big sagebrush (Artemisia tridentata) and snowberry <br />(Symphoricarpos oreophilus) dominate the overstory. Dominant grasses are western wheatgrass