Laserfiche WebLink
Page 2 of 4 <br /> From "Site Conceptual Model and Work Plan,Additional Site Investigation and Remedial Feasibility <br /> Testing, March 7, 2003" <br /> 4.4 Remedial Feasibility Testing <br /> Remedial feasibility testing will include 8 hours of soil vapor extraction(SVE)and 4 hours of air <br /> sparging(AS). <br /> 4.4.1 Soil Vapor Extraction Test <br /> To evaluate the effectiveness of SVE in remediating subsurface soils, a total of eight hours of <br /> SVE testing will be conducted, The testing will include two hours of extraction from each of the <br /> SVE wells in the nested SVE well(SVE-lNB/C), and one hour of soil gas collection from MW-1 <br /> and SVE-28. The SVE test results will be used to evaluate the following design criteria- <br /> • Relationship between subsurface airflow and pressure; <br /> • Effective permeability to airflow; <br /> • Radius of influence; <br /> • Existing soil vapor chemistry with respect to petroleum hydrocarbons; <br /> • Evidence of biodegradation; and <br /> • Feasibility of soil vapor extraction/bioventing as remedial technology. <br /> The SVE test unit will consist of a SVE blower, capable of producing air-flow at a rate of up to 25 <br /> cubic feet minute (cfm) and a vacuum of up to 15 inches of mercury. Soil vapors cxtroctcd durin <br /> the test will be filtered through two. 200-pound vapor-phase granular activated carbon vessels. <br /> prior to discharge to the atmosphere <br /> Vacuum gauges and air-tight well caps will be placed on the surrounding observation welts (MW <br /> 1, MW-2, the proposed monitoring well west of the former UST#3, and the remaining SVE wells <br /> not being used for extraction). During the SVE tests, air-flow rate, lower explosive limit(LEL), <br /> vapor concentration by PID, and vacuum will be measured every 30 minutes from the obsenratio <br /> wells- Final measurements will be made approximately 30 minutes after SVE test completion. <br /> The influent and effluent air stream from the SVE unit will also be monitored using a PID,every <br /> minutes during the SVE tests. To confirm PID measurements, influent soil vapor samples will be <br /> collected during each of the SVE tests and the soil gas collection tests. The soil vapor samples <br /> will be collected in Tedlar* bags, which will be labeled and transported with chain-of-custody <br /> documentation to a state of California-certified hazardous waste testing laboratory_ The <br /> laboratory will analyze the soil vapor samples for TPH-as-gasoline, BTEX, MTBE, DIPS. ETRE, <br /> TAME, TBA by EPA Method 6020MOl5M and/or 82608. <br /> 5/18/2011 <br />