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/\` ~` ~~ ~~y limited storage capacity of the mountain region's crystalline rocks, a further 55 percent of the annual precipitation is returned to the atmosphere by evapotranspiration. Due to the impermeability of these rocks, snowmelt and rainfall infiltra- tion account for only 3 percent of the yearly precipitation. According to the U.S. Weather Bureau, the mean annual precipi- tation that occurs at this altitude is 20 inches per year. An evaluation of the catchment area above the proposed tailings pond determined that a total of 1.267 acres of ground surface , is immediately adjacent to the embankment site. Based upon , these parameters, the catchment area will receive an average ~~ of 2.12 acre feet of precipitation annually. This amount of precipitation over the catchment area will result in 0.89 acre feet of surface runoff, 1.17 acre feet of evapotranspiration, and 0.06 acre feet of infiltration. Inasmuch as the catchment area above the tailings pond embank- ment is limited in size, water runoff inflow from rainfall and melted snow will not be significant. The rate of the surface water runoff will also be quite low, as the drainage area is on a gentle slope, with only a 20 foot difference in elevation from the top of the tailings embankment to the crest of the ground behind it. More information regarding the surface water drainage and the ground water presence on the lands that will be affected by this mining and milling operation can be found in Exhibit D under the section on Water Resources Information. Abundant waste rock from earlier mining operations is readily available near this site for the construction of the initial tailings dam structure. The nearby white Cloud and Wynona mine dumps contain approximately 30,000 tons of material, which consists of a mixture of quartz vein and wall rocks of granitic, aplitic, or pegmatitic composition. About 60 percent of this borrow source material is 3 inches or smaller in size, while 30 percent is between 3 inches and 6 inches, and only 10 percent is very coarse material that ranges up to 15 inches in size. All of the roads providing access to this millsite and tail- ings pond area were constructed many years ago. While some grading will be done to improve the surface conditions of these roads, no major relocation work will be necessary. These access roads will remain in place after the cessation of mining and milling operations by the Gold Hill Ventures Limited Partnership. Security considerations and safety monitoring of the tailings embankment were also accounted for in the selection of this site. By closing the lower access road below the tailings pond, and fencing the perimeter of the mill complex, both the property and the public can be protected from one another. Since the tailings pond will be located near the millsite, the tailings discharge and decantation lines can be easily ob- served and closely monitored. The relationship of the natural terrain and land contours to the geometry and aesthetics of the tailings embankment was also considered when this site was chosen. Because of the natural bench that exists between the 8,550 foot contour and the 8,595 foot contour interval, a rectangular shaped embank- ment was determined to be the most suitable for this location. Several natural methods will be employed to blend the tailings pond in with the existing environment. When the site is cleared for the construction of the impoundment dam, as few trees as possible will be cut down. The remaining trees and shrubs will be supplemented where necessary in order to screen the tailings pond from view. By planting new trees, and encouraging the growth of the existing trees and shrubs, the northeastern and northwestern edges of the tailings pond can be screened from observation from County Road No. 52. The -12-