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r is 680 feet. Any water flowing from this area must progress a distance of at least 3,300 feet to reach the drainage culvert. Because of the crystalline nature of the Boulder Creek gran- ite, the ground water that is found in the bedrock is only present where the granite has been fractured. Generally, the openings of these fractures (joints and faults) decrease in size with increasing depth, and the chances of obtaining water are significantly reduced below a depth of 300 feet. This crystalline bedrock has a very limited water storage capacity, and most of the remaining water that Ealls as precipitation is returned to the atmosphere by evapotranspiration. The ground water that is present in these racks probably migrates down- ward and laterally through a northeast-southwest trending fracture system towards the area above Cash Gulch. The presence of a small spring several hundred feet below the Hazel A. adit tends to support this observation. The flow from this spring varies considerably with the time of the year. It usually decreases throughout the summer and fall as the amount of water stored in the fracture system also de- creases. The U. S. Bureau of Mines drilled five test holes 200 feet south of the proposed tailings impoundment area, and monitored the amount of ground water that flowed into these drill holes. These tests established that the ground water level dropped from 53 feet to 86 feet below the surface during the period between September and December. Since it is situated 30 to 65 feet higher than the elevation of the U.S. Bureau of Mines' test area, the ground water level under the White Cloud and Wynona mines, and the proposed millsite and tailings impound- ment area, is somewhat lower than 53 feet below the surface. A similar decline in the ground water level undoubtedly occurs beneath these areas during these same months. Vegetation Information No rare, threatened, or endangered plant species have been identified in the Gold Hill area, or on the proposed mill and mine sites. The previously submitted Cash Mine Permit Appli- cation included descriptions and lists of the trees, grasses, forbs, and shrubs that have been identified in this area. The present vegetation on the land surface that will be affected by the reactivation of the Who Do, White Cloud, and wynona mines, and by the construction of the proposed mill and tailings retention structure, varies from scattered to moder- ately vegetated. Because of their acidic nature and poorly developed soil profile, the mine dumps have a vegetation cover that consists of a few small stands of Ponderosa pine and low shrubs on their eastern and southern faces. The percentage of ground covered by :•egeta<ion can be directly attributed to the date or period of the last mining activity on the property. Since the white Cloud mine was last worked during 1905, it has a thicker stand of small Ponderosa Pine growing on its mine dump than on the wynona mine dump, which was worked during the 1940's. Because the top of the Who Do mine dump was used as an ore stockpile area and roadway as late as 1946, only a few individual pines and small shrubs have grown on the thin soil base around the edges of the mine dump. while approximately 50 percent of the white Cloud mine dump is covered by vegeta- tion, the nearby wynona mine dump as only about 35 percent of its surface covered by small pine trees and shrubs. The vegetation at the Who Do mine is estimated to cover approxi- mately 15 percent of the land surface on the previously disturbed ground. About 60 percent of the area between the Who Do mine dump and the Bellevue mine dump is covered by native grasses and a few isolated Ponderosa pine and Rocky Mountain juniper trees. Approximately 70 percent of the ground where the milling complex will be located is covered by vegetation. Several small, scattered stands of Ponderosa pine -18-