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o t\) t\) w::.. recovered 0.65 ft, 3.9 days later. Potentiometric head in the USBR no. 3 well decreased 0.29 ft throughout the flow and recovery periods. Potentiometric head in the USBR no. 11 well decreased 0.18 ft throughout the flow and recovery periods. Discharges from the Hobo and Graves B Springs responded in phase with the production well. Discharge from the Hobo Spring decreased 7 gal/min during the flow period and recovere\l completely 3.5 days later. Discharge from the Graves B Spring decreased 13 gal/min during the-flow period and recovered within 1 gal/min of the initial discharge, 3.9 days later. Discharge from the Yampa Spring could not be. determined accurately, except during filling of the spring caisson, 3 days into the test. Interpretation atTest Data Transmissivity values of the Leadville Limestone and Dyer Dolomite obtained in 9 analyses of data from the Redstone 21-9 and Wright no. 1 wells ranged from 27,000 to 70,000 sq ft/d. Storage coefficient values obtained in 4 analyses of data from the Wright no. 1 well ranged from 0.00002 to 0.0007. Analyzed hydraulic properties are based on specific discharge (drawdown divided by dis- charge), residual drawdown, and recovery data for the Redstone 21-9 well and drawdown and recov- ery data for the Wright no. 1 well. The hydraulic conductivity of the Leadville Limestone and Dyer Dolomite at the test site cannot be determined with certainty. If the average trans-missivity is divided by the thickness of the fault zone penetrated by the drawdown in the Wright nb. 1 well, one of the requirements for straight- line solution of a flowing-well test, until the recovery monitoring was nearly over. Type curves pre- pared by Hantush (1960) and plotted by Reed (1980) for a situation in which a leaky confining layer is present were considered appropriate because a 41O-ft-thick section of Belden Formation, a leaky confining layer, overlies the Leadville Limestone and Dyer Dolomite in the Wright no. 1 well. The hydraulic conductivity of the Leadville Limestone and Dyer Dolomite at the test site cannot be determined with certainty. If the average transmissivity is divided by the thickness of the fault zone penetrated by the Redstone 21-9 well (35 ft), the calculated hydraulic conductivity would be 1,300 ft/d. If the average transmissivity is divided by the open interval of Leadville Limestone in the Redstone 21-9 well (74 ft), the calculated hy-draulic conductivity would be 640 ft/d. If the aver- age transmissivity is divided by the thickness of Leadville Limestone at Glenwood Springs (187 ft), the calculated hydraulic conductivity would be 250 ft/d. Finally, if the average transmissivity is di- vided by the combined thickness of the Leadville Limestone and Dyer Dolomite at Glenwood Springs (280 ft), the calculated hydraulic conductivity would be 170 ft/d. The value of 640 ft/d was reported by Geldon (1985) in a preliminary presentation of information from the RASA study. In retrospect, the value based on the combined thickness of the Leadville Limestone and Dyer Dolomite in the area, 170 ft/d, might be a better estimate of hydraulic conductivity at the test site because fractures ex- tending through the entire thickness of the two formations probably contribute water to the well. Results of the Redstone well tests should be used with caution because several of the as- sumptions underlying the analytical techniques used were violated. (1) All of the analytical techniques assume that the aquifer is homogeneous, isotropic, and of infinite areal extent. In fact, there are several faults in the area that could act as either conduits for or barriers to ground-water movement. Although the analytical techniques were developed assuming porous-media flow, interconnected fractures and solution channels in the Leadville Limestone and Dyer Dolomite probably transmit most of the water. If the fractures are aligned and not randomly oriented, hydrologic properties and ground-water movement in the Leadville Limestone and Dyer Dolomite would be distinctly anisotro- pic. A-12