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AIR SPARGING/SOIL VAPOR EXTRACTION PILOT TEST PROCEDURES ' The purpose of the`air sparging (AS) and SVE pilot tests is to collect data necessary to evaluate the performance, determine the effectiveness of, and design parameters for, an AS/SVE system The AS and SVE pilot tests will be conducted individually, then a combined test will be performed on AS/SVE well pairs Initially, the SVE system will be operational until approximate steady-state conditions are achieved, followed by AS individually, and then AS in combination with SVE for the remaining period The combined system will be operated for an extended time period (2 weeks) to determine mass removal rates over time The pre-test measurements, test procedure, test measurements, and reporting are described below Pre-Test Measurements Prior to the beginning of the AS/SVE pilot test, background readings of absolute pressure, dissolved oxygen (DO) and depth-to-water (DTW) levels ' will be collected in each vapor extraction well and surrounding groundwater monitoring wells as appropriate DTW levels will be compared to well construction logs to verify non- submerged screen lengths available for SVE ' Test Procedure The vapor extraction well shall be connected to the SVE blower The monitoring points will be temporarily sealed at the wellhead to measure vacuum The SVE blower will be started and the valves will be adjusted to provide the minimum air flow rate Total volatile organic compound (VOC) concentrations will be monitored in the SVE test well influent using a photo-ionization detector (PID) every 15 minutes The flow rate will be increased after 30 minutes of operating the system at the minimum air flow rate This procedure will continue until the maximum rate of the equipment is reached with an anticipated 4 flow rates Extraction will continue at the maximum (or optimum) flow rate for a maximum of four hours, unless otherwise specified During the SVE test, the blower ' curve will be consulted to verify flow versus vacuum readings In case of a perceived problem, the project manager or technical advisor shall be contacted immediately At the end of 4-hour period, the SVE blower will be shut down The subsurface conditions will ' be allowed to equilibrate overnight with the system turned off The AS system will be started by itself to determine the ROI of the AS system the following day The pressure will be increased until breakthrough pressure is observed (the pressure at the well will drop) The air flow, breakthrough pressure, and continuous pressure will be recorded The pressure in the surrounding wells and the water levels and DO measurements will be recorded every 30 minutes The AS system will be operated for 4 hours before starting ' the SVE system and the AS/SVE combined test commences The combined test will continue for an additional 8 days At the end of the 8-day period all equipment will be shut down, and the monitoring point well heads will be returned to their original ' configuration and the equipment will be removed from site Test Measurements Measurements will be collected at the beginning of the test and at 15-minute intervals thereafter during the individual SVE and AS tests Vacuum will be measured at the active vapor extraction well and monitoring points to determine the ROI of the active vapor well Pressure will be measure at the active air sparge well and monitoring points to determine the ROI of the active air sparge well The interval will then be increased to 30 minutes during business hours for the combined AS/SVE test The measurements will consist of flow, PID, DTW, DO, and pressure/vacuum readings VOC concentrations will be measured using a PID in the SVE test well influent to determine whether spargmg has increased or decreased contaminant concentrations in extracted vapor ' P 1280001128253 T&T Trucking SVEIAS-SVE Combined Procedures doc