2012-01-30_REPORT - C1981018 (2)

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Qa1-5 hydrograph shows a significant increase in the alluvial water level of the White River since the second half of 1985. This rise was due to the filling of Kenney Reservoir. Since that time, fluctuations reflect the seasonal rise and fall of the reservoir level. 2.2.1.2 Alluvial Water Quality Data The water quality data for Qa1-5 is contained in Appendix E. The statistical summary of the data is also contained in Appendix E. The fifth annual hydrology report noted that the general increase in the average TDS that started when Kenney Reservoir was filled was beginning to slow down. There has been a generally decreasing trend since 1992. Based on the data collected during the past water year, the TDS value was 2520 mg /I. This compares to values for the previous two reporting period of 2530 mg /I and 2360 mg /I indicating that the TDS level has stabilized. A graph showing the magnesium, chloride and TDS levels for Qa1-5 is also included in Appendix E. The water quality of the White River is considerably better than that in the alluvium indicating that permeability in the alluvium is restricted resulting in a relatively low degree of communication between the river water and the water in the alluvium. The existence of Kenney Reservoir decreases the groundwater gradient that may inhibit the natural tendency for the alluvium to flush itself of the higher dissolved solids content. The potential effects, therefore, were projected that the dissolved solids of the White River alluvium in the vicinity of Scullion Gulch would increase initially as prior unsaturated zones become saturated. TDS would then gradually decrease with time to near or slightly above baseline conditions as these zones are slowly flushed of their salts. 2.2.1.3 Bedrock Water Level Data Hydrographs for the nineteen (19) bedrock monitoring holes are contained in Appendix D. The locations of the holes are shown on Plate 1 in the pocket of this report. As noted in the original Deserado Mine permit application, the three zones being monitored (upper sandstone facies, siltstone and coal facies, and the lower sandstone) identify three different stratigraphic zones which lack the characteristics of an aquifer. The strata are too tight with little yield as demonstrated by pumping tests. The "upper sandstone facies" holes are designated by a name ending in "U ". There are three upper facies holes with water (22 -3U, 29 -4U and 33 -8U). 22 -3U is a newer hole constructed in the fourth quarter of 2005 for baseline and monitoring purposes of future mining activities. Water levels in this well appeared stable over the past year with an indicated rise of only 0.2 feet. Data for this well and other wells are shown in Appendix C. 5