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APPENDIX A <br /> AQUIFER TESTING <br /> Geweke Land Development & Marketing <br /> 16 South Cherokee Lane <br /> Lodi, California <br /> July 1994 <br /> 1.0 SLUG TESTS <br /> Two slug tests were performed on well MW-13 on July 13, 1994 The well was sounded <br /> using a Solinst interface meter A five foot section of PVC pipe filled with sand was used <br /> as a slug and was inserted into the well The initial nse in water level in the 'Aell was <br /> recorded and water level in the well was monitored every minute until it returned to the <br /> pre-test level <br /> The data was manually input into the AQTESOLV model (Duffield, and Rumbaugh, 1991) <br /> Figure 1 is a graph of the Bouwer-Race slug test solution for the data collected (Bouvier, H <br /> and Rice, R C , 1976) The calculated hydraulic conductivity (K) for the slug in test is 13 14 <br /> gallons per day per square foot (GPD/ft ) (1 218x10' feet per minute (ft/min), 1 754 feet per <br /> day (ft/day), or 6 2 x 10' centimeter per second (cm/sec)) The axis intercept 60) for the <br /> slug in test was 0 4638 feet <br /> The slug out test was performed by removing the slug from the well recording the initial <br /> drawdown and recording water levels every minute while the well recovered <br /> The AQTESOLV model was used to generate Figure 2 and calculate values for K and y0 <br /> for the slug out test Figure 2 is a graph of the Bouwer-Race slug test solution for the data <br /> collected The calculated K for the slug out test is 57 24 GPD/ft2 (4 079x10 3 ft/min, 5 874 <br /> ft/day, or 2 7 x 10 3 cm/sec) The y0 for the slug out test was 0 439 feet <br /> Assuming a 20 foot thick aquifer the calculated transmissivity (T) for the slug in slug test <br /> data would be 0 657 gallons per day per foot (GPD/ft), and for the slug out slug test data <br /> would be 2 862 GPD/ft <br /> The main limitation on slug tests is that they are heavily dependent on a high-quality <br /> monitonng well (piezometer) intake If the well screen is clogged, measured values may be <br /> highly inaccurate On the other hand, if a monitoring well was developed by surging or <br /> bailing pnor to testing, the measured values may reflect the increased conductivities in the <br /> filter pack and formation around the intake. <br /> The calculated K values fall in the range of values expected for sandy silts (Freeze and <br /> Q. 'ff P.P.""11.33 GEWQ S <br />