ARCHIVED REPORTS_XR0009267 - Laserfiche WebLink

Home Browse Search

I20 May 1999 • AGE-NC Project No 96-0254 ' Page 3 of 4 ' 3 2 LABORATORY RESULTS OF GROUND WATER SAMPLES TPH-g was detected in samples collected from well MW-IA and MW-1B at concentrations of 71 ' rmcrograms per liter(µg/1)and 3,600µg/1,respectively TPH-d was detected in the sample collected from well MW-1B at a concentration 290 µg/1 Benzene was detected in samples collected from wells MW-IA and MW-1B at concentrations of 81 4g/1 and 1300 pg/l,respectively Toluene,ethyl Ibenzene and xylenes were also detected in MW-lA and MW-1B at concentrations as high as 120 µg/1 (toluene, MWAB) MTBE was detected in the sample MW-1B at a concentration of 23 ,ug1l TPH-g, TPH-d, BTEX and fuel oxygenates were not detected in the other ground water samples collected during this sampling event Laboratory results of ground water samples analyzed for petroleum hydrocarbons are summarized in Table 2 and 3 The laboratory reports (MAI Laboratory ID 08193 to 08199), QA/QC reports and chain-of-custody forms are included in Appendix B The analysis of the ground water sample collected from monitoring well MW-3 at 2420 Grant Line Road did not detect TPH, BTEX or fuel oxygenates The laboratory report for 2420 Grant Line Road Well MW-3 is included in the Quarterly Report-March 1999 dated 07 April 1999, for Grant Line SGas and Food 4.0. SUMMARY AND CONCLUSIONS The following conclusions were drawn from the results of this investigation I0 Ground water at the site was encountered at a depth of approximately 7 to 8 feet bsg The prevailing ground water flow direction at the site is generally northward • Dissolved petroleum hydrocarbons and BTEX compounds were detected only in the samples from wells MW-1A and MW-1B • The 23 µg/I MTBE detected in the sample from MW-IB exceeds the State of California Action Limit of 13 ,ugll • The concentration of benzene in the sample from MW-1 exceeded the state maximum contaminant level (MCL) of 1 ppb i I • Advanced GeoEnviron mental Inc I