Laserfiche WebLink
29 January 1996 <br /> AGE-NC Project No. 95-0128 <br /> Page 3 of 4 <br /> 4. <br /> 4.0. FINDINGS <br /> 6W <br /> 4.1. GROUNDWATER GRADIENT AND DIRECTION <br /> Ground water depth at the site ranged from 44.13 to 44.96 feet; an average ground water elevation <br /> increase of 1.19 feet since the October 1995 monitoring. The increase in ground water elevation <br /> corresponds to a seasonal trend typically observed in the region. Ground water elevations are <br /> `~ summarized on Table 1. <br /> Using data collected on 10 November and 22 December 1995, The ground water gradient and flow <br /> direction were calculated to be 0.0038 fldft directed N 55°E and 0.0038 ft/ft directed N 67°E, <br /> respectively. Ground water elevation contours for the November and December 1995 monitorings <br /> are illustrates! in Figures 3 and 4. <br /> Because of the significant rise in ground water at the site over the past two years, the water level is <br /> .., fourteen feet above the screened interval in 114'-I and six feet above the screened ;ntervals in wells <br /> MW-2 and MW-3. <br /> 4.2. PETROLEUM HYDROCARBON-IMPACTED GROUND WATER <br /> TPH-g and TPH-d were detected in VW-1 at concentrations of 250,000 and 4,300 ygll (parts per <br /> billion- ppb), respectively. BTE&X were detected in VW-I at concentrations up to 34,000 ppb <br /> (toluene). TPH-d was also detected in the sample collected from MW-3 at 57 ppb and benzene was <br /> detected in the sample collected from MW-2 at 1.0 ppb. No ether petroleum hydrocarbons vrere <br /> detected in the samples collected. Analytical results of the ground water samples are summarized in <br /> Table 2. The laboratory report and chain-of-custody are included in Appendix B. <br /> 5.0. CONCLUSIONS AND RECOMMENDATIONS <br /> The hydrocarbon plume continues to remain in the immediate vicinity of Well VW-1. However, <br /> because the screened intervals in the other wells at the site are as much as 14 feet beneath ground <br /> water depth, samples collected from these wells may not be representative of ground water conditions <br /> in the area. Thus, the lateral extent of ground water contamination at the site cannot be established <br /> with data from the existing wells. <br /> The next quarterly monitoring is scheduled for March 1995. However, based on the continually high <br /> +.. ground water elevation, relative to the screened intervals of the monitoring wells, we recommend <br /> sampling only VW-1- <br /> r <br />