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' 28 April 1995 AGE-NC-95-0103 Page 2 of 11 ' Monitoring well MW-2 was sampled again in April of 1993 and slight increases in these constituents were reported In order to determine the e,,tent of petroleum hydrocarbons, further ground water assessment, in the form of at least tv�o additional monitoring wells, %%as required by ' PHS/EHD ' Two monitoring wells were installed at the site by GeoAudit on 29 and 30 September 1993, well MW-3 was established at a depth of I00 feet and A11N'-4 at a depth of 105 feet Total petroleum hydrocarbons as gasoline (TPH-g) and aromatic h}drocarbons (benzene, toluene, ethylbenzene and xylenes BTE&X) were not detected in any of the soil samples analyzed One halogenated hydrocarbon, bromomethane, was detected in soil sample MW445 at 0 43 pg/g (ppm) No other halogenated organics were detected in any of the samples analyzed ' In October 1993, ground water depth at the site was appro\imately SG feet and L_=round water flow was to the north Ground water in the down-gradient well (NNW-3) and cross-gradient well ' (MW-4) contained benzene (0 4 ppb and 4 1 ppb, respectively) No other petroleum h)drocarbons were detected in these wells Hoy\e,,er, TPH as gasoline, benzene, and toluene were detected in the up-gradient \%ell (MW-2) GeoAudit inferred that the Lground e ater flow direction may ha"e varied in the past, and recommended further monitoring and assessment of the extent of the hydrocarbon plume The monitoring wells \Here again sampled on 4 JanuiiN and 6 April 1994 Benzene ,Nas detected in samples from MW-2, MW-3 and 'QW-4 TPH-g «as detected in MW-3 (see Table 2) One or more chlor inated hydi ocarbons \4 ere also detected in each N\ell during each e\ent Oil 4 April 1995, remediation well VW-1 %%,is installed at the site near the center of the former UST The well was drilled to a total depth of 80 feet and completed as a 4-inch diameter remediation «ell with slotted casing from 22 to 72 feet TPH x%as detected in sample VN\11-25 at a concentration of 14,000 ppm 30. QUARTERLY GROUND NVATER NIONITORING - J-�,UARY 1995 3 1 GROUND WATER MONITORING AND SAMPLING On 27 January 1995, the depth to ground \cater in each monitoring well was measured relative to the top of the well casing using a Sohnst water level meter The relative around water ele\ations were calculated using this data After depth to eater measurements, a 2-inch Grundfos Isubmersible pump was used to purge AIW-2, MW-3 and MW-4 Between 50 and 70 gallons of water (minimum of 3 well volumes) were removed from each well to stabilize temperature, pH and conductivity before sampling Stabilization data were collected using an ICM water analyzer A PVC bailer was used to purge MW-1, which became dry upon removal of approximately only I