Laserfiche WebLink
eofo e 4 icaCTechnus Inc Pa <br /> � g g <br /> Grounlwater Monitoring Report <br /> Project No 507 2 <br /> June 19, 2001 <br /> All water purged from each monitoring well and not used as a sample was placed in a 55 <br /> gallon DOT approved container These drums were properly labeled and will be stored on <br />' site until their proper disposition can be arranged <br /> Groundwater monitoring field logs are included in Appendix C <br /> 1.3 Laboratoi y Analyses <br /> The groundwater samples collected on June 1, 2001, were delivered to California <br /> Laboratory Services (CLS), Department of Health Services Certification No 1233, of <br /> Rancho Cordova, California, for analysis <br /> CLS analyzed the eleven-groundwater samples <br />' • Benzene, Toluene, Ethyl Benzene, and Xylene (BTEX) by EPA method 602 <br /> + Total Petroleum Hydrocarbons as Gasoline (TPH-G) by EPA method 5030/8015 <br /> • MTBE, DIPE, ETBE, TAME, TBA, EDB and 1,2 DCA by EPA method 8260 <br />' • Methanol and Ethanol by GC-FID <br /> The results and detection limits for the above analyses are listed in Table 3 of Appendix A <br /> while the lab analytical results are presented in Appendix B <br />' 20 FINDINGS AND DISCUSSION <br /> The results of the groundwater sample analyses indicate the following <br /> b Wells MW-1, MW-2 and MW-3 remain free of detectable contamination <br /> • MW-4, MW-5 and MW-9 have significant BTEX and TPH-G contamination <br />' • MW-6 and MW-8 have slight contamination <br /> New water table well MW-7 contained 15 ug/i MTBE <br /> • MW-10 did not contain contaminant concentrations above the laboratory reporting <br /> limits _ <br /> New deep well MW-109 contained minor BTEX, TPH-G and MTBE contamination A <br /> vertical component to groundwater was recorded for the event, however additional <br /> monitoring is needed to conclude that it is not a drilling artifact <br /> s Figures 4 and 6 indicate a previously inverse relationship between groundwater <br /> elevation and contaminant concentrations in wells MW-9 and MW-6 These two <br /> . parameters have demonstrated parallel slopes for the past two events In Figure 5, the <br /> inverse tiend was consistent for well MW-5 for the first four monitoring events, but <br /> �; since the January 2001 event the relationship has been parallel <br />