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Aquifer Testing Standard Operating Procedure SWE-FSOP-500,•Revision 0 Ahtna Southwest Environmental Operations • Decontaminate all downhole equipment according to SWE-FSOP-801. Equipment maintained inside the pumping well from the step-drawdown test and used directly for the subsequent pumping test does not need to be re-decontaminated. • Visually inspect and access the wells used during the pumping test per SWE-FSOP-602. • Obtain a depth to water level measurement and sound the bottom of each well to be used with the electric tape according to the procedures outlined in SWE-FSOP-602. Compare the measured total depths to the bottom of the wells to their respective construction diagrams to determine if sediment is at the bottom of the wells. • If necessary, install the mechanical pump in the pumping well as described in Section 3.4.1. • If a multiple-well test is conducted, connect the pressure transducers to their respective data loggers. Install the transducers inside the observation wells at this time.The transducers should be installed at a position inside each well that is below the anticipated water level during maximum drawdown and does not exceed the maximum head limitation. Set up another pressure transducer in an outlying well (outside the suspected influence of the pumping well) to record station barometric effects, if required. If not installed from the step-drawdown test, set the pressure transducer inside the pumping well as described in Section 3.4.1. Record the depth(s) of the transducer(s). • Protect transducer cables that run across traffic areas. Data loggers should also be placed in a secure location to prevent tampering. • Turn on the pressure transducers and data loggers, and set the recording frequencies for pre- test monitoring to that specified by the project work plans. Before initiating pre-test monitoring for the pumping test, it is also important to ensure that water levels from any previous step- drawdown testing have entirely recovered. • Physically measure the water levels in the pumping and observation wells with the electric tape and record the time. Separate data sheets should be used for each well. • Commence pre-test monitoring with the pressure transducers and data loggers.The total time the pre-test measurements are made will be provided in the project work plans. Generally, water levels are recorded for a period before the pumping test that is at least as long as expected for the pumping and recovery period. Record the information, including times of measurements, on the appropriate form as specified by the project work plans. • Once the pre-test monitoring period is ended, remeasure the water levels in the wells using the electric tape and record along with the time. • Change the recording frequencies in the data loggers for the pumping test as required by the project work plans.Just before starting the pump, begin recording the pressure transducer measurements. • Start the mechanical pump and adjust the valve or flow regulator to maintain a constant rate of discharge as determined from the step-drawdown test and specified by the project work plans. Record the pump start time on the appropriate form. • Continue to monitor water levels during pumping with the pressure transducers and data loggers,taking periodic water level measurements in each of the wells with the electric tape. Data logger and tape readings should be conducted by the schedule outlined in the project work plans. However, the water level data should be evaluated during the test and, if necessary, adjust the recording frequencies of the data loggers. • Observe and record the wellhead flow meter readings as the project work plans require. Page 16 of 17