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stipulated in RWQCB Order No. R5-2003-0049. Table 2-1 summarizes site monitoring parameters, analytical methods, and monitoring frequency. Water quality samples were also analyzed in the field for dissolved oxygen, turbidity, temperature, specific conductance, and pH and recorded on well data sheets. The groundwater monitoring wells, surface water monitoring points, and leachate monitoring points were sampled in accordance with the sampling and analysis procedures detailed in Appendix B. The well data sheets, laboratory data, certificates of analyses, and chain-of-custody records for the sampling program are included in Appendix C. The laboratory analyses and field results for groundwater monitoring wells, lysimeter and leachate sampling stations are summarized in Tables 2-2 through 2-7. 2.1.2 QA/QC Results The quality assurance/quality control (QA/QC)program completed for the fourth quarter 2007 water quality monitoring event included analyses of five field blanks, four trip blanks,one equipment blank, five laboratory method blanks, and one duplicate sample. The trip, field, equipment, and laboratory method blanks were analyzed for volatile organic compounds (VOCs) by EPA Method 8260. The results of the QA/QC program indicate that carbon disulfide, chloroform, methyl t-butyl ether, and toluene were detected in one or more of the QA/QC field, equipment, and laboratory method blanks; and bromodichloromethane and chloroform were detected in one of the equipment blanks during the fourth quarter 2007 monitoring event. Review of the primary sample results indicates that none of these VOCs were detected in the primary samples collected from the Forward Unit. Review of fourth quarter 2007 sampling dates and laboratory analytical certificates indicates that with the exception of the nitrate as nitrogen and hexavalent chromium concentrations measured in lysimeter samples, the laboratory analyses were completed within required holding times. During the fourth quarter 2007 monitoring event, a duplicate sample was collected from well MW-19 and labeled MW- DUP. As shown on Table 2-2, the duplicate sample analyses yielded good correlation (within 5%) with the primary sample results. Based on the results of the laboratory QA/QC analyses, it is concluded that the laboratory data generated for the fourth quarter 2007 monitoring period are generally acceptable. 2.1.3 Groundwater Elevations and Contours Prior to purging and sampling, each well was sounded for water depth using a weighted electronic sounder to an accuracy of 0.01 foot, and the static water level was recorded on a Well Data Sheet(Appendix C). The groundwater elevations were calculated for each well by subtracting the depth-to-water measurement from the top-of-casing reference elevation. The current groundwater elevation data for the Forward Unit is summarized in Table 2-3. The groundwater elevation data obtained during the fourth quarter 2007 monitoring period were used to generate the groundwater elevation contour map shown on Figure 2-1. Historically, groundwater generally flows to the north and northeast towards the Austin Unit, at an average hydraulic gradient of approximately 0.001 ft/ft. However, D:\2007-0043\FomardAustin_4QO7.doc 4 Geologic Associates