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07 February 2008 AGE-NC Project No. 96-0254 Page 2 of 5 commonly occur in diesel fuel. Carbon adsorption utilizes granular activated carbon to simply "filter"organic compounds out of ground water. A third, but less common method of above-ground treatment of water is bioremediation. Contaminated ground water is "treated" by adding hydrocarbon-degrading microbes or by augmenting natural hydrocarbon degradation activities with the introduction of nutrients. 2.1.2. Feasibility Testing On 28 August 2000,a limited aquifer pump test was performed at the site.The depth to ground water was measured in wells MW2B, MW3, and MW4 using a Solinst water level meter. A two-inch diameter Grundfos submersible pump wasthen lowered into well M W 1 B.Pressure transducers were then placed in wells MW 1 A,MW 1 B,and MW7 and connected to a data logger to record drawdown data from the wells; the height of the water column in each well was measured by the datalogger in one-minute time intervals.Purge water was placed in a 4,000-gallon'Baker"above-ground storage tank. The pumping rate was calculated to be approximately 1.0 gallons per minute (gpm) during the 28 August 2000 test. The pumping rate was determined by measuring the time required to fill a 5-gallon bucket from the pumping discharge ho�A maximum drawdown of approximately 2.89 feet was observed in MW-IB after 330 mmutes of pumping. A maximum drawdown of approximately 0.15 feet was observed in MW-IA after 264 minutes of pumping. Wells MW-IA and MW-1 B were the only wells during the extraction test that were observed to have measurable drawdown. Using the Jacob Straight-Line Time-Drawdown Method, the drawdown versus time for wells MW-IA and MW-1 B was graphed on semi-logarithmic paper,from which the transmissivity and storativity were subsequently calculated. The transmissivities for wells MW-1A and MW-1 B were calculated to be approximately 293 gallons per day per foot(gal/day-ft)and 6,769 gal/day-ft, respectively. The storativity for MW-IA was estimated to be 0.78 (unitless). A radius of influence could not be determined for this pump test due to the lack of drawdown observed in the surrounding wells.Approximately 550 gallons of water were removed from MW 1B during the eight-hour test. 2.1.3. Duration and Feasibility Experience has shown that all systems involving ground water extraction require much more time than would be anticipated from aquifer tests and calculations of ground water discharge rates, and Adv"ced GmEnvironmental,Inc.