ARCHIVED REPORTS_1ST QUARTER 2008 SITE STATUS REMEDIAL SUMMARY AND GROUNDWATER MONITORING REPORT

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S E C O R • Dissolved metals by EPA 6000/7000 Series (during first and third quarters only per the MRP) Groundwater samples were collected at the UOU and MOU by Wallace-Kuhl. Groundwater samples collected from the wells sampled by Wallace-Kuhl were submitted under separate COC to Kiff Analytical and analyzed for the following: • TPHd and TPHo by EPA Method 8015M • TPHg, BTEX compounds, fuel oxygenates (MtBE, TAME, DIPE, EtBE, TBA, ethanol, and methanol), and VOCs by EPA Method 8260B K� • SVOCs by EPA Method 8270C • Dissolved metals by EPA 6000/7000 Series (during first and third quarters only per the MRP) Monitoring well construction details are presented in Table 2. Groundwater elevation and analytical data are presented in Tables 3 through 7. Certified laboratory analytical reports, SECOR Laboratory Validation forms, COC documentation, and field data sheets for the first quarter 2008 monitoring and sampling performed by SECOR and Wallace-Kuhl are presented as Appendices C and D, respectively. • 4.3 First Quarter 2008 Shallow Groundwater Results 4.3.1 Shallow Zone Groundwater Gradient Groundwater elevations for shallow zone wells at the L&M OU, MOU, and UOU, ranged from 5.90 feet below mean sea level (MSL) in well MW-3 to 2.79 feet above msl in well MW-30 (Table 3 and Figure 2). Groundwater flow direction during the first quarter 2008 was generally towards the northeast across the Site. In the western portion of the site, groundwater flow direction was to the north/northeast at an approximate hydraulic gradient of 0.004 foot per foot (ft/ft). In the northeastern portion of the site, groundwater flow direction was to the south/southwest at an approximate hydraulic gradient of 0.006 ft/ft. In the southeastern portion of the site, groundwater flow direction was to the southeast at an approximate hydraulic gradient of 0.01 ft/ft. The overall historical trend of the groundwater flow at the site is to the northeast. Historical gradient data are summarized in Table 8, vertical gradients are summarized in Table 9. A groundwater elevation contour map of the January 21", 2008 monitoring event is included as Figure 2. 4.3.2 Shallow Zone Groundwater Quality Data During the first quarter 2008, groundwater samples were collected from 25 shallow zone wells between January 21 and 25, 2008 (Table 1). Groundwater analytical results are presented in Tables 4 through 7, and are summarized below. TPHg, TPHd, TPHo, benzene, MtBE, and TBA isoconcentration contour maps are attached as Figures 3 through 8, respectively. The certified laboratory analytical reports for the coordinated groundwater sampling events conducted by • SECOR and Wallace-Kuhl are included in Appendices C and D, respectively. In addition, SECOR has attached laboratory validation forms for each individual report submitted by the 1Q08QSSRQRSRQMR.F1na1.doc 10 April 30,2008 77TW.26397.42.1307