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µg/L), and MTBE (620 µg/L) were reported in well VW-1 TBA, TAME, DIPE, ETBE, EDB, 1,2-DCA, or
<br /> ethanol were not reported in any of the upper zone wells Analytical results for the third quarter 2004 are
<br /> generally consistent with previous quarters GRO, benzene, and MTBE analytical data for the samples
<br /> collected on September 7, 2004, are presented in Figure 5 Analytical data were submitted to the State
<br /> Water Resources Control Board as required by AB2886 The electronic delivery receipt is attached In
<br /> Appendix C
<br /> Lower Water Bearing Zone (Sand Zone 2
<br /> During the site visits conducted between July 26, 2004 and September 9, 2004, free product was
<br /> measured in well MW-1 at thicknesses ranging from 0 08 and 0 16 feet In the site visits where free
<br /> product was measured in well MW-1, free product was manually bailed from well MW-1 and placed in a
<br /> properly labeled DOT approved drum pending disposal Approximately 13 gallons of a product/water
<br /> mixture was bailed from well MW-1 during the third quarter 2004 Approximately 205 gallons of
<br /> product/water mixture have been bailed to date
<br /> At the time of the third quarter 2004 monitoring event, groundwater levels had increased between 0 01
<br /> and 0 15 feet in wells MW-1, MW-10, MW-12, and MW-15 since the previous monitoring event (June 21,
<br /> 2004) Depth-to-water measurements were normalized to mean sea level (MSL) and used to construct a
<br /> groundwater elevation contour map (Figure 4) Wells that contained less than 1 foot of water are
<br /> interpreted to be dry and are indicated as "dry" on Figure 4 Groundwater flow was to the east at a
<br /> gradient of 0 036 ft/ft Groundwater flow was to the east during the previous quarter
<br /> GRO and benzene were reported in wells MW-10, MW-12, and MW-15 The highest concentrations of
<br /> GRO (100,000 pg/L) and benzene (12,000 pg/L)were reported in well MW-15 MTBE, TBA, TAME, DIPE,
<br /> ETBE, EDS, 1,2-DCA, or ethanol were not reported in any of the lower zone wells Analytical results for
<br /> the third quarter 2004 are generally consistent with previous quarters GRO, benzene, and MTBE
<br /> analytical data for the samples collected on September 7, 2004, are presented in Figure 5 Analytical data
<br /> were submitted to the State Water Resources Control Board as required by AB2886 The electronic
<br /> delivery receipt is attached in Appendix C
<br /> Domestic Well
<br /> GRO, BTEX, MTBE, TBA, TAME, DIPE, ETBE, 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 third quarter 2004 are consistent with historical data
<br /> SVE System Operation and Maintenance
<br /> Stratus conducted eight site visits during the third 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 /> During the third quarter 2004, SVE unit 1 was shutdown on September 30, 2004, due to a heating element
<br /> malfunction The system has not been re-started pending replacement of the heating element The SVE
<br /> unit 2 was shutdown on September 8, 2004, due to a blower malfunction The SVE unit 2 was re-stared
<br /> on October 4, 2004, after installing a new blower
<br /> During the third quarter 2004, the influent GRO concentrations to SVE unit 1 and SVE unit 2 fluctuated in
<br /> the ranges of 7,600 to 13,000 milligrams per cubic meter (mg/m)and 6,200 to 6,500 mg/m3, respectively
<br /> The average soil vapor extraction flow rates (including the dilution air) for SVE unit 1 and SVE unit 2 were
<br /> observed to be at 148 84 cubic feet per minute (cfm) at an average applied vacuum of 10 43 inches of
<br /> water column, and 203 06 cfm at an average applied vacuum of 10 43 inches of water column During the
<br /> third quarter 2004, approximately 2,091 pounds and 3,193 of GRO were extracted and abated by the SVE
<br /> unit 1 and SVE unit 2, respectively Influent GRO and cumulative GRO mass removed from both SVE
<br /> units 1 and 2 are presented in Figures 6 and 7 Since the system start-up, a cumulative mass of 8,623
<br /> P\Bp-Arco for URS\6100\Quarterly\2004\Arco_6100_3Q04 doc ST/rA7U5
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