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C • G.2 ,3 ,2 ,5 Data Analysis Drawdown data obtained from the pumping tests noted above were analyzed using the Cooper-Jacobs and the Theis recovery methods. Similar results were obtained with both methods. Average values for transmissivity and storage coefficient are 63.8 ft2/day and 2.53 x 10-4 respectively for the Upper Aquifer, and 322 ft2/day and 1.17 x 10-4 respectively for the Lower Aquifer (refer to Table G-2). By calculating specific capacity from the pumping test data, it would appear the Upper Aquifer is capable of producing approximately 2,000 gpm and the Lower Aquifer approximately 400 gpm. It would also appear that there is no significant hydrologic communication between the aquifers, at least in the area of the maxi-pad. G,2 ,3.2.6 Ground Water Quality '/ • G.2 ,3 ,2 ,6.1 Regional Ground Water Quality The ground water quality of Piceance Basin varies between aquifers and by location, In general, water in the Upper Aquifer is of better quality than the Lower Aquifer, In addition, the ground water in the recharge areas is of better quality than the discharge areas, The water in the Upper Aquifer is of a sodium bicarbonate type (BLM 1983). The concentration of dissolved solids increases in the direction of flow and may vary from 400 milligrams per liter (mg/1) to 2,000 mg/1, Total disssolved solid concentrations across the Lease area have been reported to vary from 650 to 9,610 mg/1, with all but this high value being in the 1,000 mg/1 range. The Lower Aquifer can also be classified as a sodium bicarbonate type (BLM 1983). Several other constituents are somewhat elevated in the Lower Aquifer, including fluoride, barium, boron, and lithium (BLM 1983). The average fluoride concentration for 27 wells sampled in the Piceance Creek Basin is ~- 20 mg/1, It is rare to have fluoride concentrations greater than 10 mgjl (BLM 1983). G-36