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r29 September 1995 . AGE-NC Project No 95-0139 ' Page 6 of 7 in Appendix E ' 4 4 GROUND WATER GRADIENT AND DIRECTION ' The relative elevation of ground water in each well was calculated by subtracting the ground water depth from the surveyed casing elevation(Table 4) Depth to ground water at the site ranges from 9 09 to 1169 feet Ground water elevation measurements made during this event are relatively similar to the measurements of the December 1994 monitoring The ground water flow direction continues to be to the north to northwest The gradient steepens from approximately 0 002 fl/ft over the'southern portion of the site to approximately 0 0045 ft/ft in the northern portion of the site (Figure 4) The gradient and flow direction are nearly identical to those measured during the December,1994 momtonng event 4 5 LABORATORY ANALYSIS OF GROUND WATER SAMPLES rw TPH-g and TPH-d were detected in MW-1 at concentrations of 3,600 and 1,400 ppb, respectively BTE&X were also detected in this sample at concentrations ranging from 7 2 ppb for toluene and 490 ppb for xylenes Sample from MW-4 was found to contain TPH-g and ethylbenzene at 280 and 1 1 ppb, respectively No petroleum hydrocarbons were detected in MW-2 or MW-3 The analytical results of the ground water samples are summarized in Table 5 The laboratory report and chain-of-custody form are included in Appendix F 5.0. CONCLUSIONS AND RECOMMENDATIONS 5 1 PETROLEUM HYDROCARBON RAPACTED-SOIL A work plan to install four soil probings to assess the extent of impacted soil was submitted to the PHS-EI-ED prior to the installation of the new USTs and discovery of additional hydrocarbon- impacted soils near the southeast corner of the property Two or three additional borings or"push points" should be installed near the southeast corner of the property Upon completion of the additional soil investigation, soil and ground water remediation methods can be considered and a Corrective Action Plan can be prepared