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laboratory under contract to Forward. During the second quarter 2008 monitoring period, samples were analyzed for the monitoring parameters stipulated in RWQCB Order No. R5-2003-0049, and the full suite of COCs, which are sampled every five years. 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, surface water stations, lysimeter and leachate sampling stations are summarized in Tables 2-2 through 2-8. 2.1.2 QA/QC Results The quality assurance/quality control (QA/QC) program completed for the second quarter 2008 water quality monitoring event included analyses of five field blanks, five trip blanks, five laboratory method blanks, one equipment blank, and one duplicate sample. The trip, field, and laboratory method blanks were analyzed for volatile organic compounds (VOCs) by EPA Method 8260. Laboratory method blanks were also analyzed for all of the analytes included in the monitoring program. The results of the QA/QC program indicate that no VOCs were detected in QA/QC blanks during the monitoring period. Review of the primary sample results indicates that mercury and manganese are suspected laboratory contaminants since similar concentrations were also detected in the laboratory method blanks for several samples collected at the Forward Unit. Review of second quarter 2008 sampling dates and laboratory analytical certificates indicates that with the exception of the nitrate as nitrogen concentrations measured in two lysimeter samples, the laboratory analyses were completed within required holding times. The holding times for nitrate as nitrogen was missed by less than 36 hours and are believed to be representative of the water quality conditions measured at the site. During the second quarter 2008 monitoring event, a duplicate sample was collected from well MW -19 and labeled DUP. As shown on Table 2-2, with the exception of hexavalent chromium, the duplicate sample analyses yielded excellent correlation (within 5%) with the primary sample results. Of note, concentrations less than the practical quantitation limit (PQL) were not included in the duplicate comparison, since these are estimated values. Based on the results of the laboratory QA/QC analyses, it is concluded that the laboratory data generated for the second quarter 2008 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 Q. The groundwater elevations were calculated for each well by subtracting the depth -to -water measurement from the top -of -casing reference D:\2008 0010\FA_2".doc 4 Geologic Associates