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Quik Stop No 121 Closure Report CCI Project No 12118 Page 7 the lower sand zone found between 65 and 75 feet during the CPT investigation Based on groundwater level measurements and well purge data, these three wells (MW-6, MW-9 and MW-10) were screened in a separate aquifer from the other shallow site wells CCI refers to this lower screened sand as the B-aquifer The groundwater level within the three B-aquifer wells ranged from 15 feet to 29 feet below the ground surface The groundwater flow direction also ranged from the northwest to east within the B-aquifer Copies of geologic cross-sections and the April 2006 groundwater surface contour maps for the A and B-aquifers are attached in Appendix B Aquifer Pump Test and Analysis On July 26, 2001, CCI conducted an aquifer pump test in well RW-1 to evaluate the hydraulic characteristics of the shallow aquifer underlying the site RW-1 is screened from 13 feet to 28 feet below grade (fbg) in clay, silty clay, and clayey sand The well is completed to 28 feet bgs, in a clayey sand To determine the bottom of the aquifer, the boring log from MW-6, located approximately 35 feet away from RW-1 and completed to 75 fbg, was used The bottom of the shallow A-aquifer was determined to lie at 41 fbg at the top of a clay unit The static depth to • water prior to pumping was 22 34 feet, within the clayey sand, therefore, aquifer conditions at the time of the test were unconfined, with an initial top of aquifer at 22 34 fbg and an initial thickness of 18 5 feet RW-1 partially penetrates the aquifer to a total depth of 27 5 feet The test was performed by installing an electronic submersible pump into well RW-1 A Hermit 2000 data logger equipped with three pressure transducers to measure drawdown were placed in the pumping well and two nearby wells (MW-3 and MW-4) Manual water level measurements were periodically recorded in four additional observation wells The water level in the pumping well was measured at 22 34 feet below the top of the well casing, with an available head of 5 32 feet Due to the low water table, CCI decided to run the test at I gallon per minute (gpm) RW-1 was pumped for 20 hours at an average rate of 1 gpm Drawdown data was recorded at RW-1 A total of 1,742 gallons of water were pumped from RW-1 during the test Due to data inconsistencies at the other observation wells, only the data from RW-1 were analyzed for both pumping and recovery conditions The data from pumping well RW-1 were analyzed by the Neuman solution for unconfined aquifer with partial penetration of the well The average value of K for the pumping and recovery test is 0 0033 centimeter per second (cm/s) or 0 0064 feet per minute (ft/min) A copy of the pump test field data sheets and results are attached in Appendix - C 3, 2400-FOOT WELL SURVEY AND SENSITIVE RECEPTORS CCI conducted a well survey at the State of California Department of Water Resources (Water Resources Board) The well survey included a search for all municipal, domestic, agricultural