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<br /> N_- !"`J i. , '� 'II -�' 1 r 7- x � ! �`� L 3 F �. J 1 1�-{., 11Y� �! Gil '��•�n, J- 16 Febru 200 1. + N 14 1' f 1•' r.. fi y , - r s'1 m f, i •r f:n 1 it' 4 t' �f i•,,?r } ii
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<br /> AGE-
<br /> age,.
<br /> GE NC�ProJectYNo?95 011�;4�
<br /> i. + �� 1 ^I �Lt'nlp} I I y' S I ln� "ilI'j Ylf.
<br /> age 4 of 5: t. Y _, ,a� Il t �.
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<br /> .SUMMARY".'
<br /> In summary, A GE found'that:
<br /> Between June
<br /> and,December 2000;the relahve•groundtyater elevation decreased anaverage
<br /> of 2:4.feet at the site: ` rl
<br /> TPH=ss was not detected irithe down gradient ground 'water monitoring well,sarnple IVIW 5' {
<br /> ' TPH-,§s+was detected.in the sam 1'es collected from well`s 1VIW-band MW-7 extendiin 'the
<br /> p g,
<br /> ''lateral'limits`of the.dissolved TPH-ss.'pluine off site;to-thio east.i BTEX compounds were
<br /> detected in six of tlie''seven'of the ground waiensairiples.
<br /> Conceritrations'ofPCE reported in the watersarriples:collected fro`in:wells MW6 and-MW7
<br /> !I
<br /> exc`eeded.the Maximum.ConWninant Level.(MCL)'of 5,µg/1 established by.the'state of
<br /> California - Department of Health Services.
<br /> m Concentrations of cis 1,2'di6hloroethene reported in MW6 (840 µg/1) and�MW3 (120µg11),
<br /> exceeded the MCL 6f-6 ,ccg11. -
<br /> Concentrations of vinyl chloride reported,in MW3 (130 4gll) and.MW6.(80,ug/1)'exceeded
<br /> 'i r the MCL df 0.5 µg/1:
<br /> 5.0 CONCLUSION . J .•. ` . ;
<br /> ' Based'upon the results of the'invcstigation,:AGE�concluded that ;
<br /> +
<br /> Wells at.the site are"drowned°'with well'screen'intervals as much,as 1'1,feet.below present
<br /> ground water,surface:, V
<br /> The lateral extent of the.dissolved halogenated-hydrocarbon plume has'not been definedeast
<br /> of well MW-6 and MW-7.
<br /> • As soil results'indicate from the previous drilling event,the,vertical'extent of the dissolved"
<br /> hydrocarbon plume as not been defined'in the former UST area.
<br /> 6-0 RECOMMENDATIONS i
<br /> Based'upon.the results of the investigation; AGE recommends:'
<br /> _ Installation of 2-'cone penetrometer,testirig,soil.borings to define the groundwater flow units s
<br /> and vertical extent of impacted',soil'and.groun_d'.water. Installation of additidnafground'water' ' W'
<br /> ' . ' s 1' ' •AdvancedrGeoEnviromaent
<br /> al;•Inc.
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