Laserfiche WebLink
a v s <br /> Remediation Activities—Third Quarter 2003 <br /> In August and September 1999, SECOR Installed a vapor extractionlair sparging system at the subject site to <br /> remediate hydrocarbon-Impacted soils and groundwater The vapor extraction system consists of ten wells <br /> (W-1 through W-8, MW-1 and MW-3) manifolded within the remediation compound Vapors are extracted <br /> with a blower and destroyed with a catalytic oxidizer with a destruction efficiency of at least 95% The air <br /> sparging system consists of 4 wells (AS-1 through AS-1) An air compressor is used to introduce air Into the <br /> sparging wells, and recovered vapors are destroyed with the SVE system System operation began <br /> December 13, 1999 <br /> Based on the analysis of influent samples, SECOR estimates that 16 7 pounds of gasoline-range <br /> hydrocarbons were removed and treated during the reporting period at an average extraction rate of 44 scfm <br /> SECOR estimates that 38,894 pounds of hydrocarbons have been removed since system startup Since <br /> February 2002, approximately 62 gallons of free product have been balled from MW-1, free product has not <br /> been observed 1n MW-1 since July 2002 Tables A-1 and A-2 in SECOR's report Include soil vapor <br /> analytical results and system efficiency results <br /> The remediation system operated consistently throughout the reporting period Influent samples collected on <br /> July 8, August 19, and September 2, 2003 confirmed that the system was operating within the requirements <br /> of the air discharge permit <br /> Future Site Activities <br /> Due to low recovery rates, permission has been obtained from San Joaquin County Public Health Services to <br /> temporarily turn off the remediation system during Fourth Quarter 2003 SECOR is currently generating a <br /> Site Conceptual Model to evaluate the effectiveness of remediation efforts and determine if the site qualifies <br /> • for"no further action" status If the results of the Site Conceptual Model indicate that the site qualifies for"no <br /> further action" status, SECOR will request site closure If needed, the remediation system will be restarted <br /> during First Quarter 2003 to determine if a rebound in hydrocarbon concentrations has occurred <br /> If you have any questions regarding these matters, please do not hesitate to contact me at(206)286-4495 <br /> Sincerely, <br /> Time Oil Co <br /> Anastasia E Duarte-Wilkinson <br /> Environmental Toxicologist <br /> cc Ms Elizabeth Thayer <br /> California Regional Water Quality Control Board <br /> . letters/calif/4049/4049161 doc <br /> 2 <br />