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developed on this site for a minimum of four years o£ milling operations at the anticipated rate of milling activity. The topography of this site is suitable for the construction and maintenance of a hillside tailings pond, with gentle open slopes. The subsurface conditions are ideal for constructing a stable embankment and safely containing the tailings that will be produced. The entire area is one of low seismic activity, and there is little risk to the tailings pond embankment from earthquake activity in this location. The terrain above the proposed tailings pond that could provide a precipitation catchment area is limited, and there are no streams above or directly below this site. Abundant waste rock from previous mining operations is readily available for use in constructing the impoundment dam, which will be sized and segregated as a result of the White Cloud and Wynona mine dump sorting operations. This site is readily accessible during adverse winter weather conditions, and its close proximity to the millsite will make security and safety monitoring much easier. There are no homesites located below the proposed tailings pond, and the private access road that traverses the property below the site will be closed to the public during the life of the operation. Finally, by supple- menting the existing trees and shrubs, the tailings pond and embankment area will be well screened from public view. The proposed tailings pond site is situated on 2.125 acres of land that is encompassed by the boundaries of the Oscar and Hercules patented lode mining claims. A small portion of intervening land is covered by the JoAnne unpatented lode mining claim. Topographically, the proposed tailings impoundment area can be characterized as gently sloping terrain. The present slope gradient of the ground that has been selected varies from 16 percent on the northeastern edge of the site to 14 percent on the southwestern edge. The absence of even an intermittent stream channel through this area makes this site a suitable one for the construction of a hillside tailings dam. A geological investigation of the site was conducted to determine the subsurface and surficial conditions of the tailings disposal area. This examination disclosed that the entire area is underlain by Precambrian Boulder Creek granite. Typical Boulder Creek granite is a moderately dark gray, coarse-grained, pink and black mottled biotite granite. It forms several conspicuous small outcrops in the area studied for foundation suitability. The granite bedrock present here will provide a very competent and relatively impervious foundation for the tailings dam. Although the proposed tailings pond is situated on portions of three lode mining claims, there are no old mine workings beneath this area. Both the Oscar and Hercules Lodes were located on very tight, narrow veins, which proved uneconomical; and [he only mine workings in this area are a few shallow prospect pits and trenches that probably date from the 1880's. A geologic examination of the surficial soil overlying the bedrock in t iTi location ievea e a thin mantle of soil between 3 and 6 creex granite, ana it contains no transported material. Geologically, this is a very stable environment, with no evidence of faulting or significant zones of weakness in the bedrock, and a shallow soil covet with no pattern of dis- similar or compressible soils. A very important factor in the selection of this location for tailings retention was the hydrological investigation, which focused on the precipitation, ground water, and potential water runoff inflow. Hosed upon historical streamflow rec- ords, the U.S. Geological Survey has calculated that 42 percent of the annual precipitation in Boulder County's mountain region flows to the plains each year. Because of the -11- Ex d, d;f Q