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<br />' Appendix A - Site
<br /> . PP Summary
<br />' AGE-NC Project 95-0130
<br /> Page 4 of 5
<br />' PVC piping installed underground from SVE wells VW-1 through VW-3 to the inlet of the
<br /> SVE remediation system The SVE remediation system consisted of an electric catalytic
<br /> oxidizer vapor recovery system (Solleco Ecat 250 ) Initial influent SVE air flow samples
<br /> detected TPH-g at concentrations as high as 98,000 µg/1,BTEX compounds as high as 1,400
<br /> µg/l benzene, 5,500 µg/l toluene, 690 �Ig/l ethylbenzene, 3,100 µg/l xylenes and MTBE as
<br /> high as 520µg/l Results of the August 2004 SVE interim remediation start-up were reported
<br />' in Quarterly Report - Third Quarter 2004, dated 29 December 2004, prepared by AGE
<br /> • November 2004 - An P&T interim remediation system was initiated and continuously
<br />' operated at the site The P&T system utilized a manifold network of two-inch diameter,
<br /> Schedule 40 PVC piping installed underground from ground water extraction wells EW-1
<br /> and EW-2 to the inlet of the P&T remediation system The P&T remediation system
<br />' consisted of transferring petroleum-impacted water through to a 5,000-gallon holding tank,
<br /> from the holding tank, water was treated by passing through a low profile air stripper, then
<br /> through four 2,000 pound media vessels containing liquid phase granular activated carbon
<br />' (GAC) Following treatment, water was discharged underground via 1-inch diameter PVC
<br /> piping to the City of Stockton sewer system,discharge piping is connected to a sewer clean-
<br /> out located in a east section of the site, approximately 100 feet east-northeast of the pump-
<br /> and-treat system Initial influent P&T samples detected TPH-g at concentrations as high as
<br /> 69,000 µg/l, BTEX compounds as high as 11,000 µg/1 benzene, 8,800 µg11 toluene, 3,100
<br />' µg/l ethylbenzene, 16,000 µg/l xylenes and MTBE as high as 7,100 µg/1 Results of the
<br /> November 2004 P&T interim remediation start-up were reported in Quarterly Report -
<br /> Fourth Quarter 2004, dated 30 March 2005, prepared by AGE
<br /> Between January 1995 and December 2004, thirty-seven ground water monitoring events were
<br /> performed at the site to monitor dissolved petroleum hydrocarbon concentrations in ground water
<br />' and to characterize ground water flow direction and gradient on the site Generally, TPH-g was
<br /> detected in water samples collected from wells MW-1, MW-2, MW-3, MW-6 (A, B, C, D and E),
<br />' MW-7 (B, C, D and E), MW-8, VW-1 (B and C), VW-2 (A and B) and VW-3 (A and B) at
<br /> concentrations as high as 390,000 dig/l, BTEX compounds as high as 92,000 µg/l and MTBE at
<br /> concentrations as high as 440,000 µg/l, low concentrations of tert-amyl methyl ether (TAME),tert
<br /> butanol (TBA), ethylene dibromide (EDB) and 1,2-dichloroethane (1,2-DCA) were detected from
<br /> wells MW-1, MW-2, MW-3, MW-6 (B and C), MW-7B, VW-1 (B and C), VW-2 (B and C) and
<br /> VW-3A on isolated occurrences
<br />' Generally,the depths to ground water in wells MW-1 through MW-8 were measured between 36 and
<br /> 60 feet bsg, ground water elevation at the site was calculated to be between approximately between
<br /> 20 and 44 feet below mean sea level The general ground water gradient at the site was calculated
<br /> to be approximately 0 004 ft/ft or approximately 21 feet per mile and generally directed towards the
<br /> . northeast
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<br /> Advanced GeoEnvironmental,Inc
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