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<br /> upper water bearing zone wells, these two wells were not used in contouring Groundwater flow was
<br /> generally to the south at a gradient of 0 091 ft/ft Groundwater flow in the upper water bearing zone has
<br /> been to the south-southeast and toward the southwest during previous quarters
<br /> GRO, benzene, and MTBE were reported in wells VW-2 and VW-3 GRO and benzene were also
<br /> reported in wells MW-13, VW-5, and VW-6 The highest concentrations of GRO (47,000 pg/L) and MTBE
<br /> (170 µg/L) were reported in well VW-3, and the highest concentration of benzene (6,400 µg/L) was
<br /> reported in well VW-2 1,2-DCA (5 2 pgIL) was reported in well MW-13 TBA, TAME, DIPE, ETRE, EDB,
<br /> or ethanol were not reported in any of the upper zone wells Analytical results for the fourth quarter 2004
<br /> are generally consistent with previous quarters GRO, benzene, and MTBE analytical data for the
<br /> samples collected on December 20, 2004, are presented in Figure 5 Analytical data were submitted to
<br /> the State Water Resources Control Board as required by AB2886 The electronic delivery receipt is
<br /> attached in Appendix C
<br /> Lower Water Bearing Zone Sand Zone 2
<br /> During the site visit conducted on October 14, 2004, free product was measured in well MW-1 at a
<br /> thickness of 0 10 feet, and during the site visit on December 20, 2004, free product was measured in well
<br /> MW-15 at a thickness of 0 05 feet Approximately 7 gallons of product/water mixture were manually
<br /> bailed on October 14, 2004 and December 20, 2004, and stored in a properly labeled DOT approved drum
<br /> pending disposal Approximately 198 gallons of product/water mixture has been manually bailed to date
<br /> Product thickness measurements and volumes of liquid bailed are summarized in Table 1
<br /> At the time of the fourth quarter 2004 monitoring event, groundwater levels had increased between 0 07
<br /> and 040 feet in wells MW-1, MW-10, MW-12, and MW-15 since the previous monitoring event
<br /> (September 6, 2004) Depth-to-water measurements were normalized to mean sea level (MSL) and used
<br /> . to construct a groundwater elevation contour map (Figure 4) Wells that contained less than 1 foot of
<br /> water are interpreted to be dry and are indicated as "dry" on Figure 4 Groundwater flow was generally to
<br /> the east-southeast at a gradient of 0 036 fVft Groundwater flow has been to the east during previous
<br /> quarters
<br /> GRO and benzene were reported in wells MW-10 and MW-12 The highest concentrations of GRO
<br /> (57,000 pg/L) and benzene (8,700 pglL) were reported in well MW-12 1,2-DCA (150 pg/L) was reported
<br /> in well MW-10 MTBE, TBA, TAME, DIPE, ETBE, EDB, or ethanol were not reported in any of the lower
<br /> zone wells Analytical results for the fourth quarter 2004 are generally consistent with previous quarters
<br /> GRO, benzene, and MTBE analytical data for the samples collected on December 20, 2004, are
<br /> presented in Figure 5 Analytical data were submitted to the State Water Resources Control Board as
<br /> required by AB2886 The electronic delivery receipt is attached in Appendix C
<br /> Domestic Well
<br /> GRO, BTEX, MTBE, TBA, TAME, DIPE, ETRE, EDB, 1,2-DCA, or ethanol were not reported in the
<br /> domestic well GRO, benzene, and MTBE analytical data are presented in Figure 5 These analytical
<br /> results for the fourth quarter 2004 are consistent with historical data
<br /> SVE System Operation and Maintenance
<br /> Stratus conducted eight site visits during the fourth quarter 2004 to conduct operation and maintenance of
<br /> the SVE systems, and to collect compliance samples The systems identified as SVE unit 1 (SL No
<br /> 9321) and SVE unit 2 (SL No 9230) were started for continuous operation beginning March 15, 2004
<br /> SVE unit 1 was shut down on September 30, 2004, due to a heating element malfunction, the system has
<br /> not been re-started
<br /> SVE unit 2 was shut down on November 3, 2004, and re-started on November 4, 2004 Stratus collected
<br /> a set of influent and effluent air samples on November 4, 2004, and then shut down the SVE system
<br /> K 1Bp-Arco for URS161001Quarterly120041Arco_6100_4Q04 doe 5T"TV5
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