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o N tv W (Redstone 21-9) well and the observation (Wright no. 1) well was the same as in the previous test. Potentiometric heads in the three U.S. Bureau of Reclamation wells were calculated from water levels. Wells USBR no. 1 and USBR no. 3 had Stevens Type - continuous analog recorders installed, with floats attached to record water levels. Discharges from the Graves B and Hobo Springs were measured directly with 90' V-notch weirs. The Hobo Spring was equipped with a Stevens Type-- recorder, with a float attached to continuously register the height of water above the weir. Discharges from the spring were calculated using the formula for a 90' V-notch weir (Anderson, 1977, p. 150). After the test, leakage around the 0' weir was discovered (John Ozga, U.S. Bureau of Reclamation, oral commun., 1985). As a result, discharges from this spring recorded during the test are inaccurate. However, changes in discharge recorded during the test probably are accurate. Unlike the first test, potentiometric heads observed in the Wright no. 1 well during the second Redstone well test were affected not only by discharge from the Redstone 21-9 well but also by commercial manipulation of the Yampa Spring. Eighteen hours before flow from the Redstone 21-9 well began, the Yampa Spring was diverted from the Glenwood Hot Springs Lodge and Pool to the Colorado River, increasing the discharge from the spring and lowering the potentiometric head in the Wright no. 1 well. When flow from the Redstone 21-9 well began, potentiometric head in the Wright no. 1 well decreased further. Seventy-two hours into the flow phase of the test, the Yampa Spring was diverted back to its original outlets. This decreased the discharge of the spring and initiated recovery of potentiometric head in the Wright no. 1 well. After flow from the Redstone 21-9 well was terminated, additional recovery of potentiometric head in the Wright no. 1 well occurred. Separation of total drawdown and recovery into components caused by the Yampa Spring or Redstone 21-9 well alone had to be accomplished to analyze the hydraulic conductivity between the Redstone 21-9 and Wright no. 1 wells. This separation was accomplished by application ofprin- ciples of superposition. When the Yampa Spring and Redstone 21-9 well were causing drawdown in the Wright no. 1 well, the total drawdown was equal to the sum of the drawdowns that would have occurred had either the Yampa Spring or Redstone 21-9 well been operating independently. When the Yampa Spring discharge was decreased to its prediversion rate, but the Redstone 21-9 well was still flowing, the drawdown in the Wright no. 1 well equaled the drawdown caused by the Redstone 21-9 well minus the recovery caused by decreased discharge from the Yampa Spring. When flow from the Redstone 21-9 well was terminated, the residual drawdown in the Wright no. 1 well equaled the difference between drawdown that would have resulted had the Redstone 21-9 well continued to flow and recovery caused by terminating flow from the Redstone 21-9 well and restoring the Yampa Spring discharge to its prediversion level. The second Redstone well test occurred from November 12 to 20, 1984, and included a flow period of 4.0 days and a recovery period of 3.9 days. Discharge from the Redstone 21-9 well de- creased from 2,300 gal/min at the start of the flow period to 1,740 gal/min when closing of the flow valve began. During the flow period, discharge from the well surged as much as 120 gal/min, possi- bly because of cyclic steam build up and release. The average discharge during the flow period was 1,830 gal/min. Potentiometric head in the Redstone 21-9 well, adjusted for atmospheric pressure changes, decreased 8.12 ft during the flow period and recovered 7.70 ft, 3.9 days later. Potentiometric heads in the Wright no. 1 and USBR no. 1 wells responded in phase with the production well, but potentiometric heads in other wells decreased throughout the test. Potentiomet- ric head in the Wright no. 1 well, adjusted for atmospheric-pressure changes and fluctuations in the discharge of the Yampa Spring, decreased 0.74 ft during the flow period and recovered 0.57 ft, 3.9 days later. Potentiometric head in the USBR no. 1 well decreased 0.83 ft during the flow period and A-ll