ARCHIVED REPORTS_QUARTERLY MONITORING REPORT FIRST QUARTER 2007

Home Browse Search

Quarterly Monitoring Report Page 8 Morton-Alco&Unocal Operable Units April 27,2007 ' WKA No. 6324.02 ' ■ MW 11 at 18.7 µg/L ■ MW37 at 25.2 µg/L ■ MW38 at 39.1 µg/L ■ MW39 at 18.9 µg/L ■ 2AMW-15 at 21.4 µg/L ■ 2BMW-1 at 88.5 µg/L Tables 2, 3, and 4 summarize laboratory analytical results from the site and include the most recent laboratory results. Figures 4, 5, 6, 7, and 8 show the concentrations of TPHd, TPHmo, TPHg,benzene, and MTBE (respectively) in groundwater at the site from this sampling event. Appendix B includes the laboratory reports for this sampling event and copies of each coordinating chain-of-custody. ' 5.3 Data Quality All samples were received by the laboratory under documented chain-of-custody. United States ' Environmental Protection Agency SW-846 (EPA 2000)protocols for sample storage and preservation were followed. The results of analyses for this sampling were not flagged for holding times or dilutions. The laboratory reported the following anomaly based on their review of the laboratory results: Laboratory p Report 54688 • "Hydrocarbons reported as TPH as Motor Oil do not exhibit a typical Motor Oil chromatographic pattern for samples MW5 and MW8. There are discrete peaks present which may or may not be petroleum related." A Qualifier was attached to the surrogate 2,4,6-Tribromophenol associated with EPA Method ' 8270C, analysis for sample MW6. The laboratory reported that for those samples, "Surrogate compound recovery was out of control due to matrix interference. The associated method blank surrogate spike compound was in control and,therefore, the sample data was reported without further clarification." Ethanol was detected in RN1 and RN2 at concentrations of 6.0 µg/L and 8.0 µg/L, respectively. Ethanol was only detected in MW7 and MW8 of the environmental samples (groundwater). All rinse water was obtained from a distilled water vendor and new unused rinse-water containers ' were used for all cleaning of reusable equipment. The source of ethanol in the rinse water samples RN and RN2 is suspected to be an anomaly.