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�Z��� <br /> Working To Restore Nature <br /> Report on Vapor Extraction Test January 29, 1993 <br /> Coca-Cola Former Distribution Facility, Stockton, California 5400601 <br /> Long Term Test <br /> The long term test was conducted using VEW-3 as the vapor extraction well VEW-3 is <br /> located in the former tank pit Seven wells VEW-1, VEW-2, and VEW-4 through VEW-8 <br /> were used as the observation wells RESNA operated the IC engine on VEW-3 for about <br /> two hours, while monitoring the change in induced vacuum response at the seven <br /> observation wells The vapor extraction well air flow rate held constant at 26 2 cubic feet <br /> per minute (cfm) at an applied vacuum of 10 inches of water column, and 2000 engine <br /> RPMs (revolutions per minute) After the IC engine operated for 30 minutes, a vapor <br /> sample was collected for laboratory analysis, as well as an effluent vapor sample from the <br /> IC engine off-gas stack to determine IC engine treatment efficiency A second sample was <br /> also collected for laboratory analysis at the end of this test (120 minutes) A portable <br /> Bacharach 503A explosimeter and oxygen meter was used to monitor soil gas oxygen <br /> concentrations, petroleum hydrocarbon vapor concentrations, and lower explosivity limit <br /> (LEL) from each extraction well during the vapor tests and during vapor sampling The <br /> Bacharach explosimeter provides order of magnitude readings only, and is subject to the <br /> results of laboratory analyses of air samples <br /> Short Term Test <br /> The short term test was conducted using VEW-1 as the vapor extraction well This second <br /> test was used to collect additional data to assist in determining the effective radius of <br /> influence at the wells, and to determine changes in petroleum hydrocarbon concentrations <br /> in the subsurface gas Seven wells (VEW-2 through VEW-8) were used as observation wells <br /> The IC engine was operated on VEW-1 for 30 minutes, and induced vacuum changes were <br /> monitored in the seven observation wells The air flow from vapor extraction well VEW-1 <br /> ranged from 82 8 cfm to 109 cfm at applied vacuums of 85 to 100 inches of water After 30 <br /> minutes an air sample was collected for laboratory analysis <br /> After these tests were completed, the vapor extraction equipment was relocated to each of <br /> the observation wells and operated for 20 minutes on each well before influent air samples <br /> were collected at each well for laboratory analysis <br /> Air Sampling <br /> Air samples were collected through a 1/4-inch Teflon sample line connected to a stainless <br /> steel wellhead fitting, and collected in UV-rated Mylar air sample bags Teflon tubing was <br /> used to minimize sample loss through adsorption and the possibility of distorted results from <br /> sample lines contaminated by a previous test run The samples were sealed in the air <br /> 9 <br />