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dependent on the amount of drawdown available, transmissivity of the water bearing zone and the real <br />extent of the water bearing zone. Specific capacity is a common term used to relate well production with <br />drawdown. A general rule of thumb is that a domestic or stock well should have a specific capacity of at <br />least 1 gpm/ft. One gallon per minute per foot of drawdown, for example, means that 20 feet of available <br />drawdown is necessary to have a well that will produce 20 gpm, which is a low capacity well. <br />• <br />• <br />Only one of the alluvial wells (Qal-3) (besides WFU-1 discussed later) showed any real promise as a <br />location for a water supply. The transmissivity of 3855 gpd/ft is at least a factor of 10 less than would <br />normally be expected for alluvium. However, the specific capacity of 8 gpm/ft shows promise. The <br />extremely low transmissivities show that fine material contained in the alluvium is clogging the pore spaces, <br />effectively slowing any water movement. A well drilled for a water supply in the alluvium should, therefore, <br />be completed with a carefully designed well screen along with an extensive development. All tests of the <br />Upper Sandstone Facies resulted in very low transmissivity values (from 3.8 to 74 gpd/ft). With one <br />exception, measured maximum drawdowns ranged from about 180 feet to 426 feet using pumping rates <br />ranging from 0.56 to 27.5 gpm. The exception was from 310136-2U, where the maximum measured <br />drawdown was only 1.83 feet, but the pumping rate was only 0.56 gpm. <br />It was noted during exploratory drilling that more water was produced from both locations 310135-4 and <br />310136-2 than from any of the other holes. These locations are farthest downdip of any other hole on the <br />lease area and penetrate a massive sandstone that does not exist updip. <br />Aquifer testing shows the Siltstone and Coal Facies to be extremely tight with very low transmissivities. This <br />is borne out by the long period of time it takes for water levels to stabilize in observation wells. <br />The Lower Sandstone Facies also is very tight, and water levels are very slowly responsive. Aquifer testing <br />produced transmissivity values ranging from 0.8 to 10. The only location where a value for the coefficient of <br />storage could be calculated in the aquifer testing program was in the Lower Sandstone Facies at 21012-7. <br />The calculated storage coefficient was 1.0 x 10-5, which is the normal value for a confined aquifer. <br />If either the Upper or Lower Sandstone Facies under Red Wash has been fractured by a fault, the <br />transmissivity of a narrow zone along the wash might be increased several times. This zone might be a <br />source of domestic water if the quality was found to be satisfactory following proper well construction and <br />development. However, faults are generally absent in the area. <br />II.C.3.f Identified Aquifers Only two potential aquifers have been identified during the course of this field <br />program. One is the massive sandstone in the upper part of the Sandstone Facies in the southwest corner <br />of Section 36. This sandstone is not an aquifer in the normal sense of the word, but is saturated bedrock <br />with low permeability. The depth below the surface to this saturated zone at well 36-2 is about 135 feet. <br />The water quality results of a sample collected from this well are contained in Attachment G. There are no <br />known uses of the water in this aquifer. The piezometric surface in this area is shown in Figure II.C-26. A <br />Permit Renewal #3 (Rev. 8/99) <br />II.C-69 <br />