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Aquifer Testing Standard Operating Procedure SWE-FSOP-500,•Revision 0 Ahtna Southwest Environmental Operations equipment has not been removed from the well site. In that case, the equipment may not have to be decontaminated for the testing. • If the contaminant histories are known or suspected for the wells to be tested,the tests may then be performed, starting with the least contaminated and ending with the most contaminated.This will reduce the potential for cross-contamination between wells. • Visually inspect and access the well per SWE-FSOP-602. • Obtain a water level depth measurement and sound the bottom of the well 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 using the manufacturer's instructions. Place the pump in the well so that the pump intake is near the bottom of the well screen or the location of water entry into the well. 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 motor housing and 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. • Immediately before turning on the pump, physically measure the water level in the well. Start the mechanical pump and adjust the valve or flow regulator to maintain a constant discharge specified by the project work plan or as determined from the well development records.The discharge rate should be sufficient to maintain a stabilized sustainable drawdown of at least 0.1 feet. Record the time of the start of the specific capacity test on forms specified in the project work plans. • Once pumping starts, physically measure the water level decline with the electric well tape (or equivalent) as directed at time intervals specified by the project work plans. Observe and record the wellhead flow meter readings at intervals specified by the project work plan. Record these measurements and the time on the appropriate form. • Once the drawdown stabilizes (i.e.,the water level under pumping is relatively stable), continue pumping for a sufficient time as specified in the project work plans.The project work plans will specify the criterion for stabilization of water levels and drawdown. During this time period, continue to physically measure and record the water levels at intervals stated in the project work plans. • Once the specified period has elapsed,take a physical water level measurement with the electric tape and shut the pump down. Record the measurement and time on the appropriate form. • The data should be reviewed in the field to ensure that valid data have been collected.This includes verification that discharge was maintained at a constant rate and the drawdown stabilized at the minimum required magnitude. Complete all documentation on the appropriate form as outlined in the project work plans. • The specific capacity test may be repeated as necessary and as required by the project work plans. • Once all tests are satisfactorily completed for the well, all downhole equipment may be removed and the wellhead secured. Page 12 of 17