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<br /> A S S O C I A T E S I N C
<br /> GROUNDWATER MONITORING
<br /> On November 25, 1997, an ATC Associates technician measured the water levels in wells MW-1
<br /> through MW-5, well RWA, piezometer PZ-1, and vapor wells VW-1, VW-2d, VW-3, VW-4,
<br /> VW-5s, and VW-5d No floating product was noted in any site well Groundwater monitoring
<br /> data are summarized in Table 1
<br /> The depth to water measurements and the elevations of the well casings (Table 1) of wells MW-1
<br /> through MW-5 and RW-1 were used to evaluate the groundwater flow direction and gradient
<br /> beneath the site The groundwater elevation beneath the site decreased an average of 1 75 feet
<br /> since April 9, 1997 The groundwater gradient for November 25, 1997 showed groundwater
<br /> flowing to the east at a gradient of approximately 0 003 ft/ft which is consistent with previous
<br /> groundwater gradients The groundwater gradient for November 25, 1997, is depicted on Figure
<br /> 3
<br /> GROUNDWATER SAMPLING
<br /> On November 25 and 26, 1997, at the direction of Mr Steve Sasson of PHS/EBD, groundwater
<br /> samples were collected from wells MW-1 through MW-5, well RW-1, piezometer PZ-1, and
<br /> vapor wells VW-1, VW-2d, VW-3, VW-4, VW-5s, and VW-5d for laboratory analyses The field
<br /> methods used are presented in Attachment 1 Field purge logs are included in Attachment 2
<br /> Groundwater samples were analyzed by State-certified American Environmental Network (AEN)
<br /> laboratory for total purgeable petroleum hydrocarbons (TPHg) using Environmental Protection
<br /> Agency (EPA) Method 8015 modified, total extractable petroleum hydrocarbons (TPHd) using
<br /> EPA Method 8015 modified, and benzene, toluene, ethylbenzene, and total xylenes (BTEX) using
<br /> EPA Method 8020, and oxygenate fuel additives using EPA Method 8260 Copies of the
<br /> laboratory reports and chain of custody documentation are included in Attachment 3
<br /> ANALYTICAL RESULTS
<br /> Results of laboratory analyses indicated dissolved TPHg was detected in the samples from wells
<br /> MWA, RW-1, PZ-1, VW-1, VW-2d, VW-4, VW-5s, and VW-5d at concentrations ranging from
<br /> 80 parts per billion (ppb) in PZ-1 to 34,000 ppb in well VW-2d Various BTEX constituents
<br /> were detected in wells MWA, MW-2, RW-1, PZ-1, VW-1, VW-2d, VW-4, VW-5s, and VW-5d
<br /> TPHd was detected in wells MW-1, MW-2, MW-4, MW-5, RW-1, PZ-1, VW-4, and VW-5d at
<br /> concentrations ranging from 60 ppb in MW-4 to 2,900 ppb in VW-5d Methyl tertiary butyl ether
<br /> was detected only in vapor wells VW-2d, VW-4, and VW-5d No other oxygenate fuel additives
<br /> were detected in any other wells Results of laboratory analyses are summarized in Table 2
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<br /> w 19436719436754QSR97 doc 2
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