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<br />10/10/00 TUE 17:10 FAX 1 916 861 0430 SECOR-SACRAMENTO Z013
<br />Chevron Products Company 4
<br />FOr r_C.hevrpn Station #9-577$,301 West Ketticman Lane. Ukd[ Ctifumia
<br />2 is creating a capture zone on- and offsite (see attached Figure 1). This is preliminary
<br />data and will be confirmed by continued monitoring and capture zone analysis.
<br />The extent of the hydrocarbon plume in the direction of the municipal well has been
<br />defined by soil and groundwater samples collected from wells MW -8A and —8B
<br />(located between the site and the municipal well). To date, although hydrocarbons,
<br />including MtBE, have been reported in soil samples from onsite borings, no detectable
<br />concentrations of hydrocarbons have been reported in any of the offsite borings.
<br />Additionally, groundwater samples from offsite wells have been reported nondetect,
<br />with the exception of shallow well MW -9 and deep zone well MW -1 OB. MtBE
<br />concentrations reported in wells MW -9 and MW -1013 on July 24 and 25, 2000 were 3.5
<br />ppb and 5,8 ppb, respectively. Further lateral and vertical definition of the plume is
<br />discussed in the Work Plan for Additional Site AsserymentlRemedial Well Installation
<br />dated October 9, 2000.
<br />C&A Order No. 11 requires you to include analyses for erhano4 methanol, ethylene
<br />dibromide, and 1,2-dichloroethane. A 26 July 2000 letter from Secor stated that these
<br />analyses were mistakenly omitted, that monitoring wells were resampled on 24 July,
<br />and results would be submitted when all analyses are complete These analytical
<br />results were not included in the 25 August FRP, and we have not received them as a
<br />separate submittal. These are all violations of the C&A Order No. 5-00-704.
<br />During the second quarter 2000 sampling event, Chevron's sampling contractor,
<br />Gettler-Ryan, omitted analysis of the above listed fuel oxygenates (ethanol, methanol,
<br />EDB, and 1,2 -DCA). This oversight was reported to the RWQCB in a letter dated July
<br />26, 2000. The results of the re -sampling performed on duly 24, 2000 were reported in
<br />the August 25, 2000 FRP; however, nondetectable concentrations of fuel oxygenates
<br />were not included in the comment portion of the table submitted with the FRP. The
<br />results of the July 24, 2000 re -sampling indicated nondetectable concentrations of
<br />ethanol, methanol, EDB, and 1,2 -DCA (see Table 2 of Gettler-Ryan's Groundwater
<br />Monitoring and Sampling Report Third Quarter Event of July 24, 2000, dated
<br />September 5, 2000). Per the NOV, the 3rd quarter monitoring report will be submitted
<br />to the RWQCB on or before October 15, 2000.
<br />To address item number 1 of the NOV, as of this date, the following actions have been
<br />completed at the site:
<br />• August 24, 1998 —The five former USTs, hydraulic hoists, dispenser islands,
<br />and associated product piping were removed by Musco Excavators (Gettler-
<br />Ryan, Soil Sampling During Underground Storage Tank and Piping Removal,
<br />dated November 10, 1998),
<br />August 31, 1998 - The area beneath the eastern end of the middle gasoline UST
<br />was over -excavated from 16 to 22-1/2 feet bgs (Gettler-Ryan, Soil Sampling
<br />477,41991 0431october 9.2000.doc
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