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The coal storage and tipple area of the Loadout is situated on alluvial and colluvial materials <br />overlying the Lewis shale. Waters from the Lewis shale are primarily calcium or sodium <br />bicarbonate type although sulfate type water also occurs in the Lewis shale. The source of sulfate <br />is the reduction of sulfide minerals and organic materials in the shales. <br />The Lewis shale has low hydraulic conductivity (low permeability). It is generally considered to <br />be an aquitard that retards transmission of surface water to the underlying regional aquifer, the <br />Twentymile sandstone. This low conductivity results in low well yields which, along with poor <br />water quality characteristics, precludes the use of Lewis shale waters for use other than stock <br />watering (Seneca II-W Permit Application, HGTI application Attachment 7-1). <br />The alluvial material also has relatively low hydraulic conductivity (approximately 0.1 to 0.01 <br />feet/day) due to its high composition of silts and clays. These alluvial waters are of poor quality <br />due to the proximity of the Lewis shale, contributions from agriculture, and the ephemeral nature <br />of Dry Creek (although the applicant reports that water is taken from Dry Creek below the <br />Loadout and used for irrigation). <br />Please see Section B, Item III of this document for discussion of the probable hydrologic <br />consequences (PHC) of the Loadout and railroad loop on ground water quantity and quality and <br />for a further discussion of the ground water monitoring plan. <br />Vegetation <br />Baseline vegetation information is found in Tab 4, Exhibits 4-1 and 10-1 of the permit <br />application. <br />Existing vegetative communities within the permit area consist of dryland and improved <br />pasturelands, and native rangelands. Pasturelands that were disturbed during construction of the <br />Loadout have been revegetated to intermediate wheatgrass, crested wheatgrass, western <br />wheatgrass, slender wheatgrass, Russian Wildrye, timothy, alfalfa, and yellow sweet clover. <br />Undisturbed native rangelands are dominated by sagebrush, greasewood, and rubber rabbit brush <br />communities. The native plant species tend to be adapted to alkaline soils. <br />Wildlife <br />Detailed information on matters relating to fish and wildlife issues is found in Tabs 11 and 21 <br />and Exhibit 11-1 of the permit application. A summary of that information is found both here <br />and in Section B, Item XII of this document (along with findings relevant to fish and wildlife <br />issues). <br />Four habitat types have been distinguished and described for the permit area: 1) aquatic areas <br />associated with streams and impoundments, 2) saline/alkaline shrublands, 3) saline/alkaline <br />meadows and 4) areas disturbed as a result of construction of the Loadout, abandoned croplands <br />and lands improved for pasture. Lists of possible species of mammals, birds, reptiles and <br />amphibians of non-critical concern have been constructed using distribution latilong studies <br />developed for the State of Colorado.