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<br /> ' 21;66tober 1996 r ,
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<br /> ' ' •AGE-NC-95-01.09` I'" . • ' • . , F • ,. ., f' 'f� . -.. - ��•
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<br /> Soil gas''samples ere=collected from each monitoring point ,after'tiie well--had been purged for
<br /> approximately threI e to;f v'e-minutes, using'an,electric air pump:The gas.w1 1 . as then-drawn through the
<br /> y ' feld iA.' ' rn .. and'.the measurement'was'record'ed�after stabilizatibn'.,,.Thejresults of the soil.gas
<br /> monito4ng;are'included in'Table 3•
<br /> .r,
<br /> 2:4: HYDROCARBON MASS'BALANCE'CALCULATION•1N''SOIL'
<br /> 4%
<br /> The estimated mass of hydrocarbon-compounds rernairiing inAe•soil at the site was calculated'using-�4
<br />' ainalytical,results from, soil samples collected. from progress borings '(P 1 to P 16). The;site was,' ',
<br /> divided-into four horizontal layers with depth;iniervals of 15 to•22'fee-t•;bsg,'22'to 27'feet bsg, 27 fo�;;•-
<br /> `,38 feet bsg and 38 to 55 feet bsg.;Tl 'analytical'resuIts•of,soilsamples were•plotted on'a site map,
<br /> and the areas of impacted soil-outlined,(See Appendix'E).'The mass of hydrocarbon within-each"area
<br /> was estimated,using the.de th`interval thickness, the area of the,im acted soil and the- 'average
<br /> r' p . . P
<br /> ,hydrocarbon concentratian'As estimated from the boringsoil sarraples.'
<br /> -3.0., FINDINGS
<br /> 3.1'.- . MICROBIOLOGICAL ACTIVITY•,IN GROUND WATER
<br /> 'Microbioo1
<br /> o ical"
<br /> 1
<br /> ate counts fro
<br /> m ground Ovate-r.
<br /> les collected, u•
<br /> in the third q'uarter.of 1996sam
<br /> showeda geheral.increase.,Nutrient concentrations''hdve.also shown a'general slight increase at the '
<br /> site during the;past,quarter Cherriical,arid microbiological.data for ground water are summarized on
<br /> .N s. ' L. -
<br /> Table`1 and Table` 2.,,The laboratory reports (A: Keith Kaufman•-July 29.1996 and'Septernber 26
<br /> 1996)-,and chain-of-custody•forrr�s'are included iii Appendix B
<br /> I ,
<br /> 3.2. $ GROUND WATER GRADIENT AND:DIRECTION '
<br />� F 'The de th,to •ro�ind'w ..�•�~ ' ' � ;•�� ' >< �• �� .- . . :. •,, . •• �;
<br /> ..7 p ground ater'ranged from 58.0 feet,below'surfaceigrade,(bsg)"at the:norih end of the
<br /> site'to 60:2 feet lisg south of'the site. The ata irzdicates'arr average'drop of'ground'Water elevation "
<br /> of'3:23'feet since'June:1996.-Gro4i1nd water alevations,46 summarized<on'Table 4.. b
<br /> ' _ tai ,L 1 ' t 1 fi • 'S.' c1 { _, 1
<br /> ' :Groundwater eleya#ion contours, based upon data collected on 17� epterriber 1996,'are;depicted in ,y
<br /> Figure 3.'The flow.di rectionis to wards:the'south and;-`as"m previous.moriitoririg events,.the gradient`
<br /> steepens towards theaouth erid of the site:
<br /> '.7., ' •' 4 f '� 7 7 y 1, �. F ;I. —. •} r , i
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