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<br /> Ion- and off- site to approximately 105 feet bsg utilizing cone penetrometer testing (CPT)
<br /> . technology to characterize the geological and hydro-geological framework and to assess
<br /> preferential migration pathways Laboratory analysis of grab water samples detected
<br /> substantial petroleum-impact from CPT-lA and CPT-2A to depths of 105 feet bsg Results
<br /> of the CPT investigation were reported in Quarterly Report - Second Quarter 2000, dated
<br /> I31 July 2000, prepared by AGE
<br /> • September 2001 -AGE installed two multi-level ground water monitoring wells(MW-6 and
<br /> MW-7) to depths of approximately 142 feet bsg at the site to assess the vertical extent of
<br /> petroleum-impact Screen intervals were installed at depths between 35 and 45 feet bsg
<br /> (Interval A), 50 and 55 feet bsg(Interval B),70 and 75 feet bsg(interval C), 100 and 110 feet
<br />' bsg(Interval D)and between 125 and 142 feet bsg(Interval E) TPH-g and BTEX-impacted
<br /> water was detected from both wells at sampling intervals B, C, D and E at concentrations as
<br /> high as 160,000µg/l,MTBE-impacted water was detected from MW-6(B and C)and MW-7
<br /> (B, C and D) at concentrations as high as 420 gg/1, 1,2-DCA was detected in samples
<br /> collected from MW-6 (B and C) and from MW-713 at concentrations as high as 210 µg/1
<br /> Results of the September 2001 investigation were reported in Multi-Level Monitoring Well
<br /> Installation Report- Third Quarter 2001, dated 01 March 2002, prepared by AGE
<br /> Between January 1995 and September 2002, twenty-eight 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), VW-1 (B and C), VW-2 (A and B) and VW-3 (A and B) at concentrations
<br /> as high as 390,000 pg/l, BTEX compounds as high as 92,000 µgll and MTBE at concentrations as
<br />' high as 440,000 �ig/l, low concentrations of tert-amyl methyl ether (TAME), tert butanol (TBA),
<br /> ethylene dibromide (EDB) and 1,2-dichloroethane (1,2-DCA) were detected from wells MW-1,
<br /> MW-2, MW-3, MW-6 (B and C), MW-7B, VW-1 (B and C), VW-2 (B and C) and VW-3A on
<br />' isolated occurrences
<br /> Generally,the depths to ground water in wells MW-1 through MW-7 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/f1 or approximately 21 feet per mile and generally directed towards the
<br />' northeast
<br />' 5.0. REGIONAL GEOLOGIC SETTING
<br />' The property is situated within the Great Valley Geomorphic Province of California, a large,
<br /> elongate, northwest trending, asymmetric structural trough The Great Valley Province has been
<br /> filled with thick sequences of sediment ranging in age from Jurassic to Recent,creating a nearly flat-
<br /> lying alluvial plain,extending from the Tehachapi Mountains in the south to the Klamath Mountains
<br /> in the north The western and eastern boundaries of this province are comprised of the California
<br /> Coast Range and the Sierra Nevada, respectively Rocks composing the basement complex of the
<br />' APPENDIX A
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