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Water Quality Monitoring Report Forward Landfill 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 2-6 and cumulative tabulated data for all monitoring points and constituents for groundwater, unsaturated zone, leachate, and surface water are presented in Appendix C. 2.1.2 CIA/QC Results The quality assurance/quality control (QA/QC) program completed for the first quarter 2014 water quality monitoring event included analyses of one trip blank, laboratory method blanks, and one duplicate sample (MW -19). The trip blank was analyzed for volatile organic compounds (VOCs) by EPA Method 8260 and method blanks were 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 trip or method blanks during the current monitoring period. Inorganic constituents including chloride and sodium were measured at trace concentrations in method blanks analyzed with groundwater and leachate samples. However, these constituents were measured at very low concentrations that did not affect the interpretation of primary sample results. The results of the duplicate sample collected from well MW -19 yielded generally good correlation with a relative percent difference (RPD) of generally less than ten percent. 40 Only strontium had a RPD above ten percent (17 percent). Review of the sampling dates and laboratory analytical certificates indicates that all laboratory analyses were completed within required holding times. Based on the results of the laboratory CIA/QC analyses, it is concluded that the laboratory data generated for the first quarter 2014 monitoring period are acceptable and the water quality samples collected from the Forward Unit appear to be representative of water quality at the site. 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 on February 4, 2013 were used to generate the groundwater elevation contour map shown on Figure 2-1 for the first quarter 2014 monitoring period, which indicates that groundwater beneath the southern and central portions of the Forward Unit generally flows to the northeast at a hydraulic gradient of 0.003 ft/ft, while groundwater beneath the northeast corner of the Forward Unit flows to the southwest at a hydraulic gradient of 0.016 ft/ft. This southwest gradient was first noted during the May 2011 monitoring event and is believed to be related to M:\ 2014.0012\FA_1Q14.docx 5 4/28/2014, Rev. 0