Laserfiche WebLink
Document management portal powered by Laserfiche WebLink 9 © 1998-2015 Laserfiche. All rights reserved.
q1 <br /> Date* February S,2003 <br /> Quarter, 4`h Quarter,2002 <br /> Groundwater Samples Collected on 12/19/2002: <br /> Based on the review of the analytical and hardcopy data (chain-of-custody records, blanks,dilutions, holding times, <br /> LCS/LCSD results,MS/MSD results,and surrogate recoveries),the data are acceptable as reported by the laboratory <br /> with the following limitations <br /> • The reporting limits for tert-butyl alcohol (TBA) in samples VW-12,MS-1B,MS-2A,MS-2B,MS-3A <br /> and MS-3B have been raised due to instrument contamination which may cause false positive results <br /> • The elevated reporting limits for the Method 8260 analysis of sample VW-8 were due to the presence <br /> of high levels of non-target compounds(possibly 2-methyl pentanc) <br /> • The elevated reporting limits for the Method 8260 analysis of sample VW-10 were due to the presence <br /> of high levels of non-target compounds (probably total petroleum hydrocarbons as gasoline (TPHg) <br /> and/or benzene,toluene,ethylbenzene,total xylenes(BTEX)) <br /> • The reported results for TBA, methyl tert-butyl ether (MtBE), di-isopropyl ether (DIPE), ethyl tert- <br /> butyl ether (ELBE) and tert-butyl ether (TAME) in samples VW-2, VW-8, VW-10 and VW-1I may be <br /> biased low since the analyses for these samples were performed 2 days beyond the U S EPA <br /> recommended holding time of 14 days <br /> • The reported result for MtBE in sample MS-3B may be biased high as demonstrated by a high <br /> surrogate recovery clue to matrix interference <br /> • Although not noted on the associated sample receipt form, sample MS-lA was not received nor <br /> analyzed by the laboratory <br /> DISCUSSION: <br /> TPHg, BTEX, and the fuel oxygenates MtBE, TBA, and DIPE were reported in samples from site wells for this <br /> reporting period TPHg,ethylbenzene, and MME were reported at historic highs in well VW-7 at concentrations of <br /> 160, 13, and 11 Ag/L, respectively Historic highs of MtBE concentrations were also reported in wells VW-1 and <br /> VW-12 (6 4 and 2 6 ug/L, respectively) With the exceptions noted above, analyte concentrations were generally <br /> consistent with historic data The approximate direction of groundwater flow was to the southeast with an average <br /> hydraulic gradient of 0 002 ft/ft <br /> This report is based on data, site conditions, and other information that are generally applicable as of the date of the <br /> report,and the conclusions and recommendations herein are therefore applicable only to that time frame <br /> TABLES <br /> Table 1 Groundwater Monitoring Data <br /> Table 2 Groundwater Analytical Results for Oxygenates <br /> Table 3 Groundwater Gradient Data <br /> FIGURES <br /> Figure 1 Groundwater Elevation Contours <br /> Figure 2 Groundwater Analytical Summary <br /> APPENDICES <br /> Appendix A Field and Laboratory Procedures <br /> Appendix B Laboratory Analytical Reports,Chain-of-Custody Documentation,and Field Data Sheets <br /> K Vi BP ARC0N021301Q.=ff1YW_QTR 0M130GWM1R4Q0y doe Page 2 <br />