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S E C 0 R ' 2003 Feasibility Test Summary Report September 18, 2003 ' Page 2 3.1.1.1 Slug Test Data Analysis ' Slug test data was evaluated using AOTESOLV®, a computer application using an analysis technique described by Bouwer and Rice (1976), incorporating AOTESOLV®. The slug test was performed to estimate parameters of hydraulic conductivity(K) and transmissivity(T). ' Slug test data results (Table 1), suggest the hydraulic conductivity ranges from between 0.96 feet per day (ft/day) and 73.59 ft/day, and transmissivity ranges between 12.50 square feet per day (ft2/day) and 2,502 ft2/day. Data plots are included in Appendix C. The results of slug test activities are within the range of ' published values (Freeze and Cherry, 1979) for unconsolidated silty sands. The results are consistent with sediments encountered in the borings for each test well (Appendix D). Additionally, boring logs do not indicate the presence of a confining layer. ' 3.1.2 Pump Test On November 5, 2001, TROLLS were installed in pumping well MW-9A and observation wells MW-1, ' MW-2, and MW-11 to monitor water levels before and during aquifer testing. The data loggers in the observation wells were programmed to collect information in one-minute intervals. The data logger in the pumping well was programmed to collect information on a logarithmic time scale. Copies of pump test ' data sheets are included in Appendix E. 3.1.2.1 Baseline Test Results 'i On November 5, 2001, prior to initiating aquifer testing, baseline data was collected to evaluate the possible presence of antecedent trends in static groundwater levels. In addition, barometric pressure data was obtained from the National Oceanic and Atmospheric Administration (NOAA) station located at ' Metropolitan Airport in Stockton, California to evaluate the possible effect on static water levels due to significant changes in barometric pressure. Baseline data collected prior to the aquifer pump test indicated the presence of antecedent trends at the ' site. Specifically, baseline data collected from groundwater monitoring wells MW-2 and MW-9A indicated that groundwater levels at the site were rising at an average rate of 1.3x104 feet per minute (ft/min). Baseline data collected from MW-1 and MW-10 indicated that vroundwater levels at these wells were ' rising at average rates of approximately 9.5x10.5 and 7.0x10 ft/min, respectively. Based on data obtained from the NOAA station, barometric pressure during baseline data collection and the aquifer pumping test, varied between 29.95 and 30.21 inches of mercury (in. Hg) (33.84 and 34.14 feet of H2O, respectively). Plotting barometric pressure data versus observed water level data indicated a barometric ' ratio of 0.66 (for every foot of rise in groundwater elevation groundwater elevation decreased by 0.66 feet from barometric pressure). ' 3.1.2.2 Step-Drawdown Test Results On November 5, 2001, a step-drawdown test was conducted on MW-9A. An initial pumping rate of one gallon per minute (gpm) was used. Manual water level measurements indicated that the pumping rate ' could not be sustained. The pumping rate was then reduced to approximately 0.75 gpm, which could be sustained by the aquifer. 1 1