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i A S S O C I A T E S I N C ANALYTICAL RESULTS TPI-Ig and BTEX were detected above laboratory method detection limits in the samples collected from wells MW1, MW3, MW5, MW6, and MW7 The samples collected from wells MW2, MW4, and CW contained no detectable concentrations of petroleum hydrocarbons Groundwater samples from wells MW1, MW3, and MW7 continue to contain elevated concentrations of TPHg and BTEX A summary of analytical results is presented in Table 1 Laboratory data sheets and chain-of-custody documentation are contained in Attachment 2 GROUNDWATER FLOW DIRECTION Water level measurements were collected from wells MW1 through MW7, and CW on August 19, 1999 Water levels ranged from 20 49 to 23 66 feet below the tops of the well casing elevations, representing an average increase in the water table elevation of approximately 0 11 feet since March 1999 The water level data were used to develop the groundwater elevation contour map (Figure 3) Assuming that horizontal isotropic conditions prevail, groundwater in the uppermost aquifer beneath the site flowed towards the northeast The average hydraulic gradient on August 19, 1999 was calculated to be 0 008 ft/ft or approximately 42 ft/mile A summary of groundwater monitoring data is presented in Table 1 . CONCLUSIONS Concentrations from wells MW1 through MW7 and CW remain consistent with the results from previous sampling events It appears as though there are petroleum hydrocarbons remaining in the soil The direction of groundwater flow and the magnitude of hydraulic gradient are consistent with the previous event Groundwater elevations have increased since March 1999 RECOMMENDATIONS Based on the results of the Second quarter 1999 monitoring episode, we recommend the following o Conduct the Third Quarter 1999 groundwater monitoring and sampling wells MW1 through MW7 and CW and analyze samples for TPI-Ig and BTEX by EPA Method 8020 w 1625961quan1yUgr-1999 doe 3