Laserfiche WebLink
' Based on the groundwater elevation data from February 26, 2004, the calculated groundwater GEOMATRIX <br /> flow direction for February 2004 is south-southeast at a gradient of about 0 009 (Table 2 and <br /> Figure 3) Groundwater flow direction for first quarter 2004 is relatively uniform across the site <br /> During previous quarters the groundwater flow directions have varied from southeast to <br /> southwest across the site The groundwater gradient for the first quarter 2004 is slightly greater <br /> than previous quarters <br />' 3.2 LABORATORY RESULTS <br /> The following provides an evaluation of the quality assurance/quality control results for the <br />' laboratory analyses and presents analytical results Copies of analytical reports for the <br /> groundwater samples collected for the first quarter 2004 groundwater monitoring event are <br /> included in Appendix B <br /> 3.2.1 Quality Assurance/Quality Control Evaluation <br /> Groundwater samples collected by WGR for wells MW3-1, MW3-2, MW3-4, MW3-5, and <br /> MW3-6 were received by Precision Enviro-Tech Analytical Laboratory on February 26, 2004 <br /> Holding times for the requested analyses were met Benzene was detected at a concentration of <br /> 7 60 micrograms per liter in the trip blank, however, most monitoring well results were either far <br /> above this level or not detected, indicating the analytical results were not comprorrused <br />' Recoveries of surrogate spikes were within laboratory quality control limits <br /> 3.2.2 Analytical Results <br /> Analytical results for quarterly monitoring parameters are presented in Table 3 During first <br /> quarter 2004, groundwater samples from the five sampled wells had detectable concentrations of <br /> TPHg or BTEX <br /> Groundwater wells MW3-4 and MW3-5 are background wells, MW3-1, MW3-2, and MW3-3 <br /> are completed near the former UST, and well MW3-6 is a downgradient well Groundwater <br />' samples from the downgradient well and the wells near the former UST consistently have <br /> detections of TPHg and BTEX compounds (Table 3) Low concentrations of TPHg and BTEX <br />' compounds have been detected 1n the background wells (Table 3) <br /> During first quarter 2004, the highest concentrations of TPHg, toluene, and xylenes were <br /> detected in the groundwater sample from well MW3-2, the highest concentration of ethylbenzene <br /> was detected in the groundwater sample From MW3-1, and the highest concentration of benzene <br />' was detected in the groundwater sample from well MW3-6 <br /> I TROJECA6000c16437 000/6437 19 doc 3 <br />