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depression within the pumping well. No water will be extracted from the shallow water bearing zone via the test well for 12-18 hours following the completion of the step test in order to allow for formation equilibration. rA constant-rate discharge test will be initiated following g g formation equilibration. The constant rate test will involve the extraction of water from the test well at the rate specified by the step test. Water will be extracted from this well for a period of - 12 hours. Water levels will be measured con ' uously in the pumping well and a neighboring monitoring well during the test with pressure transducers and an i oil/water interface probe or water level meter, liRely with 30 or 60 minute spacings. Product thickness in those monitoring wells with separate phase hydrocarbons will be measured at regular intervals during the test. Groundwater samples will be collected during the first and last hour of the tet from a sampling port in the water effluent line near the pumping well. The samples will be forwarded to the project lab for analysis of concentrations TPHg, TPHd, and benzene, toluene, ethylbenzene and xylene isomers BTEX. I i The pumping test will be completed following 2 hours of groundwater extraction, or when drawdown has stabilized in MW-2, whichever occurs first. Stabilization is defined for the purposes of this test as measured drawdown of less than a tenth of the cumulative drawdown observed after the 5econd hour of pumping for three consecutive hours. For example, if a total of one foot of drawdown is measured in MW-2 after two hours of pumping, the test will be concluded following three f consecutive hourly measurements of an incremental increase in drawdown of 0.10 i. or less. A recovery test will be conducted following the completion of the constant rate discharge test. This test will consist simply of monitoring the recovery of water levels in MW-2 and the pumping well after t e pump has bee:z shut off. This recovery will be recorded using the data logger, and will occur pric r to the removal of any of the pumping equipment from the reco ery well. rPumping equipment will consist of an electric submersible pump capable of producing low to moderate flows of water., Based on the pun`_. :::gs generated during groundwater sampling, it is anticipated that the rate oi groundwater � r extraction will be between 1 and 5 gpm. Recovered. water will be directed to a temporary aboveground holding tank during he test. Based o�-- `'-e anticipated flowrate, it is expected that a tank with a 5,000 allon capacity -vv` . sufficient for the needs of this test. Water in the tank will be sampled followin .:ie completion of the test, with collected samples directed to the project laborato_ .- or analysis of fuel hydrocarbon compounds in accordance with the requirements of local water disposal facilities. Water will be disposed of foll wing acceptance by tie appropriate facility, and the rented container returned. f , D-107/PILOT TEST WP 4