|
h_ =s t W—_: — "• II�* r _..� �r _ � ..�, —� — —_ a" _ s i— — c — .,k _ _ _ � i z O-�— .�,t>.
<br /> I L r l r 5
<br /> 17 July 1997 T�
<br /> AGE-NC Project No 95-0142
<br /> „ Page 2 of 4 `I `
<br /> 22 GROUND WATER SAMPLE COLLECTION
<br /> r I V iY r r d 7 ,y
<br /> Water samples were collected from each purged well (MW-3, MW-4,-MW-5, VW-1 through VW-4)
<br /> using new, clean, disposable plastic bailers Immediately upon retrieval, the samples were,rtransferred ,�
<br /> into 40-m1 VOA vials containing 0 5'milliliters of 18% hydrochloric acid,as a preservative and were
<br /> 'L °y `then placed inra chilled container The samples were transported in under chain-of-custody to
<br /> IMcCampbell Analytical, Inc , (MAI) in Pacheco, California for analysis
<br /> All samples' were analyzed in, accordance, with EPA Method 8015/5030 for total petroleum ,
<br /> hydrocarbons quantified as gasoline (TPH-g), and in accordance with EPA Method 602 for volatile`
<br /> organic compounds (benzene,,toluene, ethylbenzene and xylenes BTE&X) and methyl-tert-butyl
<br /> 1
<br /> ether (MTBE)
<br /> I 1
<br /> +}I 1 I I r L
<br /> 23 COLLECTION OF PURGED WATER SAMPLES F
<br /> Two drums of purged ground water from the March 1997 monitoring events`were on the site At the s,
<br /> request of Stockton Plating, a water sample was collected from each drum, for disposal
<br />' characterization The samples were collected using a disposable plastic bailer Two 40-m1 VOA vials ,
<br /> 10
<br /> of water were collected, labeled, placed in a chilled container_and transported under chaifi-of-custody
<br /> to MAI for analysis The sample was-analyzed for TPH-g and for BTE&X and MTBE in accordance
<br /> with EPA methods noted above r ,
<br /> I'
<br /> t r
<br /> 3.0. FINDINGS �' t,'� n ;�` <
<br /> I a
<br /> 1 GROUND WATER,GRADIENT AND DIRECTION
<br /> Ground water at the site ranged from 30 40 feet to 31 52 feet below,the well casing tops;The'average ,
<br /> ground water elevation decreased approximately 0 5,feet between March and June 1997 1 "
<br /> ,k During the June 1997 monitoring event, they hydraulic gradient'was 'approxi mately 0025 ft/ft, }
<br />' directed toward the southeast from TKI-90 The'relahve ground water elevation data is,depicte'd in ,,,
<br /> Table 1 -Relative Ground Water Elevation The relative elevation of groundwater surface at the'site �
<br /> i is illustrated on Figure 3 -Relative Ground Water Eleyatao�r
<br /> 3 2",� ANALYTICAL RESULTS OF,GROUND'WATER STAMP I°ES
<br /> TPH-g was detected in samples collected from wells.VW-1 through VW-4 at concentrations ranging i
<br /> from'320 to'160,000 parts per,biIIion (ppb, reported as micrograms per liter) BTE&X,compounds
<br /> I ,
<br /> 1 i
<br />
|