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of shrubs and browse species, and full supplemental irrigation <br />for the second season; and (4) emergency irrigation during the <br />first 5 years to maintain vegetation during any summer drought <br />periods on the more xeric slopes. This amount of irrigation <br />should provide for a positive leaching of excess salts from the <br />root zone and vigorous vegetation growth. <br />The 40 inches of irrigation water required for preliminary <br />leaching is based on a estimated requirement of twice the 15 <br />inches of elutriate required for laboratory leaching of 828 <br />of the soluble salts from a 36-inch column of processed shale <br />(Schmehl and McCaslin, 1972), plus approximately 10 inches <br />required to completely saturate a 3 foot profile or processed <br />shale. This leaching requirement has also been confirmed by <br />Colorado State University research at Anvil Points (Harbert <br />and Berg, 1978) and in water balance studies by Wymore (1973) <br />which indicate that 40 inches of water (3.3 acre-feet) applied <br />• to processed shale revegetation sites will leach the salts. <br />In addition, approximately 20 inches of water per acre (1.6 <br />acre-feet) will be applied during the first year to promote <br />seedling establishment and about 20 inches of water per acre <br />(1.6 acre-feet) will be applied the following year to ensure <br />stand establishment. Thus, a total of about 80 inches of water <br />per acre (or about 6.5 acre-feet) will be used on each site <br />for revegetation purposes. <br />Given that the processed shale disposal area will cover approxi- <br />mately 900 acres of Davis Gulch, Colony expects to utilize some <br />5,900 acre-feet of water in its 27 year revegetation program. <br />This water requirement is distributed over the life of the mine <br />in accordance with the disposal area reclamation time schedule <br />as shown below: <br />C~ <br />G-33 <br />