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STANDARD FIELD PROCEDURES FOR GROUND WATER PUMPING TESTS This document describes Cambria Environmental Technology's standard methods for performing ground water pump testing using existing ground water monitoring or extraction wells These procedures are designed to comply with Federal,State and local regulatory guidelines Specific procedures are summarized below Prefield Activities Review existing site data,including boring logs,regional hydrogeologic setting,well elevation information,and site layout Determine if pumping tests is feasible under site conditions Coordinate with site owner and/or manager to determine timing of testing Conduct site visit to assess logistics and accessibility Develop plan to handle and/or dispose of extracted ground water Secure permits for ground water discharge, if needed Determine which wells are going to be pumped and monitored,and develop estimates of pumping rates and test length Field Activities The field activities include setup, a step-discharge test,recovery period,a constant-discharge test,and a second recovery period The imtial setup includes measuring static water levels and total well depths,installing water level probes and/or dataloggers, and testing,field calibration, and programming of depth measurement and logging equipment After setup, wait for ground water to equilibrate to static conditions before the testing begins The step-discharge test will be performed for approximately 4 hours, depending on the site conditions The extraction ,,ell will be pumped at least three different pumping rates Water levels in the pumping well and observation wells and pumping rate will be monitored over time The duration of a step will be determined by the rate of change in drawdown in the extraction well Steps will typically last approximately 60 minutes The water-bearing zone will be allowed to recover before the constant-discharge test is started The depth to water in the pumping and observation wells will be observed during the recovery period The constant-discharge test will be performed for approximately 8 hours,depending on the site conditions The pumping rate will be determined from the information gathered during the step-discharge test Water levels in the pumping well and observation wells and pumping rate will be monitored over time Drawdown data in the pumping and observations wells will be plotted in the field to monitor the progress of the test Barometric pressure,tidal changes(if applicable),and changes in weather will be recorded during the test The depth to water in the pumping and observation wells will be observed during the recovery period for a period of approximately 12 hours, or until the pumping well has recovered at least 80% of its maximum drawdown Depth to water measurements will be plotted in the field to determine when to stop monitoring the recovery Data Analysis and Reporting Data analysis will be performed to estimate subsurface parameters, including transmissivity, hydraulic conductivity,and storativity The analytical methods will be determined by the type of test performed and the characteristics of the site subsurface F 1"ri:.MPLATF\SOPS\PUMPTEST DOC Page i of I