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1 <br /> STANDARD OPERATING PROCEDURE <br />' CONSTANT DISCHARGE AQUIFER TEST <br /> Purpose and Scope <br /> Aquifer testing is generally required in order to accurately calculate aquifer hydraulic parameters such as <br />' hydraulic conductivity (K), transmissivrty (T), and coefficient of storage (S) The data can be used to <br /> evaluate groundwater remediation technologies In addition, the aquifer parameters are necessary to <br /> evaluate contaminant transport The aquifer test will consist of a step test,pumping test, and recovery test <br /> Equipment Set-Up and Site Control <br /> Prior to arriving on site, the necessary permits to discharge the groundwater extracted from the pumping <br />' well into the sewer, or a water holding tank to be delivered to the site for temporary storage <br /> The aquifer test will be conducted using a submersible Grundfos environmental pump which will have a <br /> check valve A discharge hose will be connected to the pump and extend to the sewer (if permitted), or a <br /> holding tank A flow meter/totalizer will be installed to measure the flow rate and total gallons extracted <br /> during the test A globe valve will be utilized to control the extraction flow rate The pump will be set <br />' approximately one to two feet from the bottom of the well A generator, or existing electrical power at the <br /> site, will be used to power the pump Pressure transducers will be installed in the pumping well and in three <br /> observation wells The transducers will be connected to a data logger Traffic cones and caution tape will <br /> be used to surround the pumping well and associated test equipment The discharge hose and all power <br />' cords will be secured to the ground using duct tape <br /> Field Procedures <br />' Prior to the start of work, a decontamination area will be established This will be in a secured area and <br /> consist of an Alconox® solution wash, a first rinse and a second rinse Down hole equipment will be <br /> decontaminated prior to use Prior to equipment set-up, all wells to be monitored during the test will be <br />' opened and allowed to stabilize The data logger will be set-up for the conditions of the test <br /> At least 24 hours prior to the test, a step test will be performed to determine the appropriate flow rate to be <br />' used during the aquifer test The step test will be conducted in the well to be used for the aquifer test Each <br /> step will consist of pumping groundwater from the well at a constant rate until the water level stabilizes <br /> from water table disruption caused by equipment installations The flow rate will be increased in each <br /> subsequent step until the maximum flow rate that can be sustained by the well is determined <br /> Prior to starting the pump, the total gallons displayed on the flow meter/totalizer will be recorded This will <br /> be used to determine the total number of gallons extracted during the test The pump and data logger will be <br />' turned on simultaneously to start the pumping test During the pumping test a constant flow rate will be <br /> extracted from the pumping well The flow rate and data collected by the data logger will be periodically <br /> monitored during the test The duration of the pumping test will be determined by the data collected The <br />' test may be conducted for 8 to 16 hours Personnel conducting the test will determine the duration of the <br /> pumping test <br /> Once the pumping test is completed, the pump is shut off and the recover test begins Prior to shutting of the <br />' pump the data logger will be configured for the recovery portion of the aquifer test The exact time and the <br /> total gallons displayed on the flow meter/totalizer will also be recorded The pump will be turned off and <br /> data logger stepped to collected recovery data The duration of the recovery test will be determined by the <br /> data collected The recovery test may be conducted for 8 to 16 hours Personnel conducting the test will <br /> determine the duration of the recovery test <br /> An effluent water sample shall be collected during the pumping test The analytical data can be used to <br />' design a groundwater remediation system Additional sampling may be required by conditions of a <br /> discharge permit If water is being stored in a holding tank, appropriate samples will be collected per <br />