Laserfiche WebLink
GROUNDWATER GRADIENT AND FLOW DIRECTION <br /> Figure 4 shows the groundwater elevation gradient and flow direction determined from <br /> depth to water measurements at the four on-site monitor wells on March 5, 2002 The <br /> groundwater elevation has increased by an average of 1 32 feet since the previous <br /> quarterly monitoring round on December 12, 2001 The flow direction is to the <br /> northeast The overall gradient is 0 001 feet/linear foot <br /> RESULTS OF CERTIFIED ANALYSIS OF GROUNDWATER SAMPLES <br /> The i esults of the certified analyses of groundwater samples collected from the four <br /> monitor wells on March 5, 2002 are shown in Table 1 Copies of the laboratory reports <br /> are included as Appendix C of this report <br /> TPH-G concentrations in MWI-MW3 ranged from a maximum of 4200 ug/l at monitor <br /> well MWI to 2000 ug/I at monitor well MW2 Monitor well MW4, completed in a lower <br /> aquifer, showed a TPH-G concentration of 150 ug/l <br /> Benzene concentrations in MWI-MW3 ranged from a maximum of 1700 ug/l at MWI <br /> and MW3 to 510 ug/l at MW2 Monitor well MW4 showed a benzene concentration of <br /> 2 8 ug/l <br /> MTBE concentrations in MWI-MW3 ranged from a maximum of I I ug/l at MW3 to <br /> ibelow the laboratory detection limits of 2 0 ug/1 and 10 ug/l at MW2 and MWI <br /> respectively MTBE was not detected above 0 5 ug/l in MW4 <br /> Figure 5 shows the distribution of TPH-G, BTEX, and MTBE in groundwater and the <br /> estimated lateral limits of the TPH-G in groundwater as determined from ,groundwater <br /> samples collected on December 12, 2001 The lateral limits of TPR-G in groundwater to <br /> the northeast are not yet determined, however, the preliminary results from Advanced <br /> Geo-Environmental, Inc CPT testing (December 2001) to the northeast suggest that the <br /> TPH-G in groundwater plume at the first groundwater depth of 25 feet bgs most likely <br /> extends beyond the property limits <br /> RECOMMENDATIONS <br /> • Coordinate the resurvey of all monitoring well elevations with AGE at the 1211 <br /> South Turnpike and 1201 South Center sites <br /> • Prepare a workplan for the installation of offsite monitoring wells at 1211 <br /> So Turnpike Rd following the implementation of AGE's workplan to install <br /> additional groundwater monitoring wells at 1201 South Center Street <br /> 3 Arc Pump QM 1-3, 2002 <br />