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d for approximately 120 hours This monitoring was conducted to evaluate short term fluctuations in the shallow aquifer under non-pumping conditions A plot of the depth to water in RW-1 over the monitoring period is shown on PIate 2 Background Water Level Monitoring Results The static monitoring component of the test program was undertaken after the conclusion of the long term test and consisted of placing a single channel data logger and transducer into RW-1 for approximately 120 hours after the well had recovered 98% of the prepumping water level These data which are plotted on Plate 2 show an average water elevation increase of approximately 1 2 feet over the 5 day monitoring period. However, approximately one foot of ✓ this increase took place over a single 12 hour period The water level increase noted over the first several to perhaps as many as 20 hours of monitoring may represent continuing recovery from pumping The rising static water elevations after 20 hours may reflect several sources including tidal/nver stage changes, production well pumping to the area, recharge from nearby Mormon Slough and natural seasonal recharge trends These sources may be responsible for some of the fluctuations noted in the well responses during pumping, however any filtering of the data to account for these affects is well beyond the scope of this report Previous groundwater monitoring data from four separate events in 1990 shows an irregular shifting gradient which suggests complex conditions very likely related to the known production well pumping in the area It does not appear that the background trend has significantly affected the data from the pumping test. Test Results: Short-Duration Test The two short-term constant-rate tests showed a slight increase in well productivity (pumping rate/ft of drawdown) with increasing discharge rate. The specific drawdown s/Q (feet of drawdown/gpm) is plotted versus the pumping rate (gpm) for the 5 and 2 0 gpm short-term tests and the 2.5 gpm longer-term test on Figure 1 The data plotted on Figure 1 were used to evaluate the well performance. The drawdown to a pumped well consists of two components, the aquifer losses and the well losses The aquifer Iosses are generally related to laminar flow conditions and vary linearly with the pumping rate The well losses include head loss which vanes both linearly and non-linearly with well discharge rate. The linear well losses are generally related to aquifer damage during well construction The non-linear (non-darty) well losses are related to turbulent flow within the well screen, the discharge pipe, and the formation. These two components can be characterized by the following equation s = AQ + BQP (Equation 1) . where. AQ = linear head loss