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C A WB B R I: A FOURTH QUARTER 2003 ACTIVITIES; Blaine will gauge'".and sample the site wells`according to the'=existing"sampling schedule.and tabulate the data. Cambria will prepare a.groundwater.monlioring report: - `CONCLUSIONS AND RECOMMENDATIONS The analytical results-of groundwater samples collected this quarter were generally within the historical.norm for this""site..The•groundwater.flow direction ti jhe shallow zone is generally to the east'at a gradient ranging from 0.005 to 0:007. Groundwater .flow direction- in the deeper zones during the third quarter.2003 was ,to the. , southeast at.a gradient'. of 0.004. to..0.005. Based on``three quarters worth of groundwater monitoring data,.it:appears that the:groundwater flow.direction in the..80 and 120-foot zones flows.primarily:to.the south or,southeast. Analytical_Reduction Request' v Cambria.recommends reducing the `fuel oxygenate analytical suite-aU this site. Ethyl tertiary butyl:'ether(ETBE), di rsopropyl ether (DIFF), and tertiary'amy1.methyl ether(TAME) have not been detected at,this,site. The only exception to this_is one anomalous detection of TAME on May:16, 2000-in well.MW4.. Considering the number of.wells at this site;:we have analyzed for each of these three compounds.241:.,times. It,is;clear that ETBE, RIPE, and TAME are -riot a.' component of.the fuel.release associated with this site Cambria recomigends that ETBE,:DIFE, and:TAME analysis be discontinued at.thissite. ; t 'Dichloroethane (1,2.=DCA)'and) thylene dibromide:(EDB) have,rarely been' at.this site. 1,2=DCA has been:deteeted fourout'of 241':times at this site;and EDB.has been detected two out of 241 times,at this,site. 1, `A CA"has been detected awice in MW-4 and once each-in MW-11 and MW-14.. Wells MW-11:.and:MW-1,4 ate-located off site.'1The-low level,onetime detections in these wells.are:most jikely not associated with the fuel release at ahe:subject site. One.of the two detections.of'L2-DCA in 1vFW=4 was on 1VIay 16,:2000. :,The two;detections of EDB.both" occurred on May 16,`;2000 and,Were in wells MW4and_MW-3 With so many onetime, low-" level detections occurring on'thesame date (May 16, 2000) it,appears there may have been alab error or sample contamination problem on that,sampling date:. If Ve consider the May 16, 2000 data anomalous, then there have been no dete Etions of EDB.and only one detection (0.89 µg/L) of"1,2=DCA at:the subject site. It appears that EDB is not a component of-fuel releaseat the. i 4 2 1399