Laserfiche WebLink
5 <br /> 4. SUMMARY OF RESULTS, DISCUSSION AND RECOMMENDATION <br /> 1 <br /> A summary of the analytical results from current and past well samplings is presented <br /> in Table 1 Based on the water-level data for March 6, 1996 (Table 1), Smith <br /> Environmental has interpreted the groundwater gradient and flow directions for the <br /> upper and lower aquifers, as shown on Figures 3 and 4, respectively In the local <br /> upper aquifer (Monitoring Wells MW-5, MW-6 and MW-7), the groundwater level rose <br /> an average of 1 62 feet, ranging from 1 55 feet in Monitoring Well MW-6 to 1 73 feet <br /> in Monitoring Well MW-7 In the local lower aquifer (Monitoring Wells MW-1 R, MW-2, <br /> MW-3, and MW-4), the groundwater level rose an average of 1 52 feet, ranging from <br /> 1 47 feet in Monitoring Well MW-2 to 1 56 feet in Monitoring Well MW-1R The <br /> apparent groundwater flow direction in the local upper aquifer is southeasterly at a <br /> gradient of approximately 0 003 (Figure 3) The apparent groundwater flow direction <br /> in the local lower aquifer is easterly at a gradient of approximately 0 002 (Figure 4) <br /> Laboratory analyses of water samples collected on March 6, 1996 from Monitoring <br /> Wells MW-1 R, MW-2, MW-5, MW-6, and MW-7, indicated that TPH-G and BTEX <br /> were not detected in any of these samples [because of the concentration of MTBE <br /> present in the sample from Monitoring Well MW-5 it was necessary to raise the <br /> detection limits of TPH-G to 250 parts per billion (ppb) and BTEX to 2 50 ppb] MTBE <br /> was not detected in the samples collected from upper aquifer Monitoring Wells MW-6 <br /> and MW-7, but was detected in upper aquifer Monitoring Well MW-5 at a <br /> concentration of 1,100 ppb MTBE was detected at low concentrations in lower <br /> aquifer Monitoring Wells MW-1 R and MW-2 at concentrations of 23 ppb and 6 4 ppb, <br /> respectively Monitoring Wells MW-3 and MW-4 were not sampled because they are <br /> located upgradient of the underground storage tanks, and, historically, TPH-G and <br /> BTEX have not been detected in the groundwater from these wells The next <br /> quarterly groundwater sampling is scheduled for June 1996 <br /> As can be seen in Table 1, laboratory results indicate that no TPH-G or BTEX have <br /> ever been detected in Monitoring Wells MW-1R, MW-3, MW-4, MW-6, and MW-7. <br /> of these wells, MTBE was only detected in the sample from Monitoring Well MW- <br /> 1 R at a concentration of 23 ppb. 0 <br /> MV1W 184 2731QUIK 132 RPT[23 Apr 061 SI�'TH <br />