Laserfiche WebLink
18 December 2007 <br /> AGE-NC Project No. 98-0511 <br /> Page 4 of 4 <br /> i <br /> • Ground water at the site Was inferred to flow generally toward the west and northwest under <br /> hydraulic gradients of between 0.003 ft/ft and 0.008 ft/ft,which is consistent with the ground <br /> water flow pattern for this site since AGE began quarterly ground water monitoring in 1999; <br /> • TPH-g was detected in the ground water samples collected from wells MW-1, DPE-1, and <br /> DPE-2 at a maximum concentration of 8,000µg/l(DPE-2).BTEX compounds were detected <br /> in wells MW-1, DPE-1, -and DPE-2 at maximum concentrations of 320 µg/l benzene <br /> (DPE-2), 26 µg/1 toluene (DPE-2), 190 µg/1 ethylbenzene (MW-1), and 790 µg/1 xylenes ` <br /> (MW-1). TAME and 1,2-DCA were also detected in the groundwater samples collected <br /> from well DPE-2 at concentrations of 18 µg/1 and 12 µg/1, respectively; <br /> • Concentrations of TPH-g and BTEX decreased in well MW-1 and increased in well DPE-2 I <br /> thisquarter.Concentrations ofTPH-g,ethylbenzene,and total xylene all increased inDPE-1 <br /> while concentrations of benzene decreased. Graphs illustrating concentration trends of <br /> TPH-g and benzene in the impacted wells are included in Appendix D; <br /> • Analytes of concern were not detected above laboratory reporting limits in ground water I! <br /> samples collected from wells MW-2 through MW-8; and <br /> • Hydrocarbon-impacted soil and ground water are not defined laterally along the up-gradient, <br /> eastern portion of the site. <br /> f <br /> 5.0. RECOMMENDATIONS <br /> Based upon data collected from the site, AGE recommends the following: <br /> • Continuation of quarterly ground water monitoring; and <br /> • Reduction of the monitoring/sampling of wells MW-2 through MW-8 to semi-annually to <br /> eliminate unnecessary costs. <br /> 6.0. LIMITATIONS <br /> Our professional services were performed using that degree of care and skill ordinarily exercised by <br /> environmental consultants practicing in this or similar localities.The findings were based upon field <br /> measurements and analytical results provided by an independent laboratory. Evaluations of the I <br /> hydrogeologic conditions at the site for the purpose of this investigation are made from a limited ' <br /> number of available data points (i.e., ground water samples) and subsurface conditions may vary <br /> away from these data points.No other warranty,expressed or implied,is made as to the professional <br /> interpretations, opinions, and recommendations contained in this report. <br /> Advanced GmEnvitonmental,Inc. i <br />