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Approximately 2500 gallons of Gean (White River) water were pumped down the drill pipe of an <br />additional hole in an effort to circulate the foam and attendant contaminants out of the hole. However, <br />because the foam stabilizes the pressure within the hole, removing the foam prior to casing installation <br />resulted in sloughing. <br />As noted in the discussion on groundwater movement, the source of groundwater recharge to each <br />of the three bedrock hydrologic zones examined tends to move with depth from the northwest to the <br />north (in a clockwise manner). As a result, the Upper Sandstone Facies receives water which <br />originated in the headwaters of Scullion Gulch whereas water in the Lower Sandstone Facies likely <br />originated north of the lease area in the Red Wash Basin. <br />Because of the probable increase in travel distance as the recharge area changes from the northwest <br />to the north, the quality of groundwater is expected to be poorer with depth. This results from the <br />increased contact time of the water with the rocks. The low permeability of the bedrock in the area <br />indicates that groundwater is in contact with the rock for a long Time, ample time to dissolve more <br />mineral constituents in a given distance than would be expected in a more permeable aquifer. <br />Geologic conditions in the area also likely contribute to notably poorer quality groundwater with depth. <br />Water in the Siltstone and Coal Facies has more contact with the rock than in other zones because <br />of the greater surface area created by the fine-grained nature of the zone. This would normally result <br />in increased mineral solution. <br />The quality of groundwater in the three bedrock zones is generally poor, as evidenced by the alkali <br />deposits which appear along the sandstone outcrops adjacent to the White River following an intensive <br />storm and also from the analyses in Attachment B. A sample was collected in March 1981 from water <br />within the abandoned Staley-Gordon Mine. The TDS concentration was 4230 mg/I. The White River <br />alluvial groundwater is also of poor quality. The White River probably has little effect on the water <br />quality in the adjacent alluvium because of the tight nature of the alluvium (as determined through the <br />aquifer testing program) and the higher hydrostatic pressures existing in the adjacent bedrock zones. <br />II.C.3.h Groundwater Monltorlng Program The Deserado Mine groundwater monitoring program <br />originally consisted of monitoring water levels and quality in the bedrock and in the White River <br />alluvium. This program included hydrology monitoring from eleven (11) bedrock monitoring sites and <br />hydrology monitoring of six (8) White River alluvium sites. The location of sites presently being <br />monitored is shown on Map 137. Table II.C-11 shows which zones are monitored at which site and <br />where water samples are collected and water levels measured. Since ground water monitoring began <br />in 1981, several events have occurred which have changed the monitoring program. <br />In the fall of 1984, Kenney Reservoir behind the Taylor Draw Dam was filled and the resulting rising <br />water flooded and destroyed five of the six alluvial monitor holes. Only one alluvial monitor hole <br />(Oal-5) is now available for monitoring. Monitor hole 2-17L was cemented in October of 1985 as the <br />(Renewal t12, 1/94) II.C-74 - _ <br />