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- description of the lithology of the upper sandstone facies in which this well is completed is contained earlier <br />in this report. Basically though, the formation is a thick, massive, fine to medium grained sandstone <br />interbedded with gray siltstone and shale. As shown in Table II.C-11, transmissivities measured from tests <br />in the hydrology wells located in Section 36 (at site 36-2) ranged from 13 to 74 gpd/ft which is very low. <br />Specific capacities ranged from 0.02 to 0.31 gpm/ft which is also very low. As stated previously, a general <br />rule of thumb is that a domestic or stock well should have a specific capacity of at least 1 gpm/ft. Using this <br />criterion, it seems quite unlikely that it would be feasible to use the massive sandstone in Section 36 for a <br />water supply. <br />The other potential aquifer is the White River Alluvium in the vicinity of Qal-3, which is near the bridge <br />across the White River at the entrance of the lease area. During the fall of 1980, a new well was drilled 103 <br />feet south east of Qal-3 in an attempt to further define the potential of the White River Alluvium providing a <br />water supply for the mine. Because of its proximity to Qal-3 this well was not added to the monitoring <br />program, however, aquifer characteristics determined by tests in the well are important and consequently <br />are summarized here. Results of pumping to provide a water supply from this and other nearby wells are <br />contained in Section II.D on Alluvial Valleys. Information regarding this well comes from Ford, Bacon, and <br />Davis (1981). The well completion and formation logs of WFU-1 are contained in Attachment C along with <br />the results of the pump test. The transmissivity of this well as determined by the type-curve method was <br />12,410 gpd/ft (Walton, 1970 and Ford, Bacon, and Davis, 1981). Specific capacity at a pumping rate of 90 <br />gpm was determined to be 13.9 gpm/ft. These results indicate that the White River Alluvium may be useful <br />as a water supply. However, water quality remained poor during the entire pump test (i.e., total dissolved <br />solids concentration was 2590 mg/I and varied only slightly during the six hour pumping period (see <br />Attachment B for water quality analysis). <br />II.C.3.g Water Quality Groundwater quality samples were collected from each of the wells shown in <br />Figure II.C-32. These data are tabulated in Attachment G. Although efforts were made to obtain <br />representative samples, the wide range in constituent concentrations initially found within a given hydrologic <br />zone indicated that the data may be unreliable. However, later data have been collected that are felt to be <br />sufficiently reliable to indicate groundwater quality is generally poor. The poor water quality was attributed <br />initially to the methods used to drill and develop the wells. Holes were drilled using a common method <br />of air-rotary drilling refer-ed to as foam drilling in which water and foam are injected into the well to <br />disperse cuttings and lift them to the surface. The foam used in drilling was Baroid Quik-Foam, a <br />linear primary alcohol ethoxylated sulfate. This medium is biodegradable, resulting in water and <br />carbon dioxide as end products.' However, the presence of a large amount of excess carbon dioxide <br />would have an effect on a potentially large number of constituents (bicarbonate, carbonate, alkalinity, <br />acidity, pH, total dissolved solids, etc.). It was also felt that excess carbon dioxide could increase the <br />concentrations of other chemical species (including trace metals by bringing into solution constituents <br />'Sam Geffen, Baroid Petroleum Services, Denver, Cclorado. Personal comm~.anication, July 1979. <br />Permit Renewal #3 (Rev. 8/99) II.C-70 <br />