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EI��® Mr James L Barton October 29, 2004 Page 3 included in Attachment E Third quarter 2004 analytical results for TPHg benzene and methyl tertiary butyl ether (MtBE) are summarized on the respective cross-sections Remediation System Description The remediation system consists of an Air Sparge / Soil Vapor Extraction (AS/SVE) system The AS system includes an air compressor with a maximum positive displacement of 95 standard cubic feet per minute (scfm) at 125 pounds per square inch (psi) that is manifold to ten ' air sparge points and air sparge well AS-26 The system infects contaminant-free air into the subsurface saturated zone at rates between approximately 10 0 and 58 0 scfm, enabling a phase transfer of hydrocarbons from a dissolved state to a vapor phase The air is then vented tthrough the unsaturated (vadose) zone The sparge wells are manifold to the system by Schedule 40 polyvinyl chloride (PVC) The flow ' rate for each sparge well can be manually adjusted to optimize the system Additionally, each sparge well is equipped with ports that allow for the monitoring of air flow rates and pressure The SVE system includes a thermal oxidizer with a 1,000,000 British Thermal Units (BTU) burner and a positive displacement vacuum compressor rated at 400 scfm The approximate operating vacuum is 80 inches of H2O A vacuum is applied through thirteen soil vapor extraction wells, and four groundwater monitoring wells near the previously identified sources of contamination in the vadose zone soil Extracted vapor is treated using the thermal oxidizer before being released to the atmosphere The system is operated under San Joaquin Valley Air ' Pollution Control District (SJVAPCD) Permit Number N-5879-1-0 SVE wells are manifold to the system by Schedule 40 PVC piping The flow rate for each extraction well can be manually adjusted to optimize the system Additionally, each extraction well is equipped with ports that allow for the monitoring of air flow rates and or pressure Well construction details are in Attachment C and the system layout is shown in Figure 14 ' Soil Vapor Extraction System Status The SVE system was started in October 1999 as required by CAO No 5-00-707 The SVE t system was shut down in October 2003, based on RWQCB approval, as stated in their letter dated October 23, 2004 The SVE system was restarted on September 24, 2004, based on RWQCB approval, as stated in their letter dated September 10, 2004 L ,r- _ ..*__ .n nr4^Kgr 1 QQQ the RVE system has operated for a total of Mt Since starting the O V F_ -JYDLVI I 1 I.. ,.. - - - - -- 6,412 hours and has removed approximately 8,463 pounds of petroleum hydrocarbons from ' impacted soil and groundwater A summary of SVE system operational parameters, destruction efficiencies, and mass flow rates are presented in Table 4 through Table 9, respectively 1OcsacramentolprojectsTrojects10694OW96-2937inaRReports\Quartedy Mondonng ReportO098 3rd Qtr 04-QMR doc Cc-Job, inn 31` Yearrof_x�pjfa C n CnVIY(n/ Yii2 SPrvC�e