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the leachate percolates, chemical interaction of the water and soil <br /> will continue, causing the less mobile constituents to become adsorbed <br /> onto the underlying rock. The uppermost transmissive zone into which <br /> the leachate from the JD-8 property will infiltrate will be the <br /> sandstone bodies in the basal unit of the Brushy Basin Member of the <br /> Morrison Formation and in the Top Rim of the Salt Wash Member of the <br /> Morrison Formation. (See Exhibit G to the C-JD-8 Application. ) A <br /> comparison of the water quality expected from the leachate and the <br /> mine water expected from these formations (see Item #5 below) shows <br /> that leachate from the waste rock piles will not degrade groundwater <br /> quality. <br /> Design of Drainage Protection for Waste Piles <br /> In order to protect drainages and prevent the intrusion of runoff <br /> ( into the waste rock pile, a diversion and culvert have been designed <br /> for the Doagy #2 site. No diversion is necessary for the JD-8 tract, <br /> as it does not lie in a drainage. The drainage area above the Doagy <br /> #2 waste dump encompasses approximately 68 acres. The design precip- <br /> itation event chosen was a thunderstorm with a 10 year return period <br /> and a duration of one hour. The precipitation depth would be approxi- <br /> mately one inch (Miller et al 1973) . <br /> Due to the small size of the drainage area, the drainage collection <br /> structures were designed based on peak discharge using the Rational <br /> Formula rather than based on a flood unit hydrograph. The peak dis- <br /> charge (Qp) was calculated to be 41 cfs: <br /> Qp = 1 .0083 CiA <br />