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GEOMATRIX The pumping phase of the step-drawdown test will consist of: (1)pumping the well at succes- sively higher pumping rates(steps)specified by the responsible professional,with an approxi- mate duration of two to four hours per step; (2)periodically and at similar times measuring the water levels in the pumped well and observation wells during each step; (3)measuring the instantaneous and cumulative discharge from the pumped well using a flow meter or other appropriate means; and(4)recording the time at which all measurements were taken. The pumping rate for each step will be maintained relatively constant. The rate will be checked periodically(at least hourly) and adjusted if necessary. The accuracy of the flow meter also may be verified periodically using the sweep needle on the flow meter,if available, and a stop- watch. The accuracy of the flow meter will be checked using a container of known volume and a stopwatch. The recovery phase of the step-drawdown test begins immediately after the pump is shut off at the completion of the final step of the pumping phase. Recovery water-level measurements will be made periodically in the pumped well and observation wells. Water level measure- ments will conclude when one of the following is satisfied: (1)the water level in the pumped well has recovered to pre-test level, (2)the water level in the pumped well has remained con- stant for at least 2 hours; or(3)24 hours has elapsed since the time of pump shut-off. 3.0 CONSTANT DISCHARGE TEST During the pretest phase,water level measurements will be taken in the pumped well and all observation wells that are to be monitored throughout the duration of the test. Water level measurements will be taken with electric sounders,pressure transducers with a data-logger, or a steel tape. All pretest water level measurements for the pumping well and observation wells will be recorded for the appropriate well. 3.1 PUMPING PHASE During the pumping phase of the aquifer test,the following measurements will be made: (1)water levels in the pumped well and the observation wells; (2)instantaneous and cumulative discharge from the pumped well; and(3)time at which measurements are taken. The duration of the pumping phase will be established prior to the start of the aquifer test. Time-drawdown curves for the observation wells may be plotted in the field on semi-logarith- mic graph paper during the pumping phase to evaluate the progress of the test. If the plots indi- L'\Doc Safe\PROTOCOL\PROTO-AQ 0802.dm AQUIFER TESTING REVISION DATE: March 19% Page 2 of 5