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locations of aquifer test wells and other wells are shown in Figure 2; the raw pump test data is included in Appendix C. 5.1 STEP DRAWDOWN TEST Step drawdown testing is conducted by pumping water from a well at sequentially increasing rates, and monitoring the water level drawdown in the well with pressure transducers connected to an automatic data logger. The water level change in response to pumping during the first step determines the rate of increase for the following steps. Generally, four pumping steps and one recovery step are attempted. On April 13, 1993, data were generated for three pumping steps and one recovery step. Pumping steps lasted approximately 76 minutes at 1.14 gallons per minute (gpm), 165 minutes at 1.7 gpm, and 22 minutes at 2.86 gpm. At the end of pumping step 3, the water level in the well reached the pump inlet, and ground water recovery data were collected. Step test data were analyzed using the Rorabaugh approach to define well efficiency factors related to frictional and turbulent head losses. As the velocity of water entering the well increases with sequential pumping rates, head losses are also predicted to increase. Drawdown was not observed in any of the observation monitoring wells. Well efficiency calculations, which refer to the percentage of head loss caused by friction and turbulence, were attempted based on the relative change in well drawdown with increased pumping rate during the step drawdown test. Data scatter prevented the use of the this method as well as the more rigorous Birsoy-Summers method. Data scatter may represent aquifer stratification and/or delayed yield effects of the unconfined aquifer. Short term well yield is defined directly by step test data. The maximum pumping rate during testing was 2.86 gpm, which caused AW-9 to be overpumped in approximately 20 minutes. Longer term well yields are projected based on efficiency and hypothetical target drawdown. The logarithmic stabilization of the pumping rate for a desired drawdown determines the maximum long term yield. 5.2 CONSTANT RATE PUMPING TEST Constant rate pump testing is conducted by pumping water from a well at a constant rate for an extended period of time, generally greater than 24 hours, and monitoring water level drawdown in the pumping well and observation wells with pressure transducers connected to an automatic data logger. From April 14 to April 16, 1993, data were collected for 2,840.5 minutes (1.9 days) of pumping at approximately 2.0 gallons per minute (gpm) and 333 minutes of recovery (0.2 days). The 5 •