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Aquifer Testing Standard Operating Procedure SWE-FSOP-500,•Revision 0 Ahtna Southwest Environmental Operations • Visually inspect and access the well per SWE-FSOP-602. • Obtain a depth to water level measurement and sound the bottom of the well with the electric tape according to the procedures outlined in SWE-FSOP-602. Compare the measured total depth to the bottom of the well to the well construction diagram to determine if sediment is at the bottom of the well. • Install the mechanical pump in the well per the manufacturer's instructions.The position of the pump intake inside the well should be based on well construction and site-specific factors stipulated in the project work plans.The criteria for placement of the pump in the well should also be contained in the project work plans. Lower the pump inside the pumping well to a depth below the bottom of the anticipated drawdown. Note the height of the water column from the static water level to the pump intake. Record all information on the appropriate form specified by the project work plans. During testing,the drawdown should not be so great as to cause the pump to cavitate. • Connect the pressure transducer to the data logger. Lower the pressure transducer inside the pumping well to a depth below the bottom of the anticipated drawdown.The transducer should be installed at a level that: 1) eliminates effects from the pump intake, 2) is below the anticipated water level during the maximum drawdown, and 3) does not exceed the maximum transducer head limitation. In addition,the transducer must be secured inside the pumping well so that the transducer will not be affected by turbulence from the pump. Record the depth of the transducer. • Turn on the pressure transducer/data logger, and set the recording frequency for pre-test monitoring to that specified by the project work plans. (Data loggers should be kept secure to prevent tampering.) • Physically measure the water level with the electric tape and record along with the time. Begin pre-test monitoring with the pressure transducer/data logger.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 step-drawdown test that is at least twice as long as expected for the step-drawdown test and the 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 level using the electric tape and record the time. • Change the recording frequency on the data logger to the appropriate frequency of step- drawdown data entry as required by the project work plans. Begin recording water level measurements with a pressure transducer/data logger as needed for the project work plans for the initial pumping phase of the step-drawdown test. Start the mechanical pump and adjust the valve or flow regulator to maintain the constant rate of discharge specified by the project- specific work plan.This rate will be the first step in the step-drawdown test. Record the time of the start of the step-drawdown test as specified in the project work plans. • Continue to monitor water level decline during the first step with the pressure transducer/data logger,taking periodic water level measurements with the electric tape. Data logger and tape readings should be conducted by the schedule outlined in the project work plans.As the first step continues, review the water level data and, if necessary, adjust the recording frequency of the data logger. Observe and record the wellhead flow meter readings as the project work plans require. Page 14 of 17