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v Water Quality Monitoring Report Forward Landfill Table 2-1 summarizes site monitoring parameters, analytical methods, and monitoring frequency. Water quality samples were also analyzed in the field for oxygen reduction potential (ORP), turbidity, temperature, specific conductance, and pH and recorded on well data sheets. The groundwater monitoring wells and leachate monitoring points were sampled in accordance with the sampling and analysis plan 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 2-6 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 QA/QC Results The quality assurance/quality control (QA/QC) program completed for the second quarter 2014 water quality monitoring event included analyses of two trip blanks, one field blank, one equipment blank, laboratory method blanks, and one duplicate sample (MW -23R). The trip, field, and equipment blanks were 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 carbon disulfide was measured in field, trip, and equipment blanks at trace concentrations ranging from 0.62 µg/L to 0.71 µg/L. Accordingly, carbon disulfide has been flagged as a field/laboratory contaminant on Table 2-2. Inorganic constituents including chloride, sulfate, magnesium, and potassium were measured at trace concentrations in method blanks analyzed with groundwater 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 -23R yielded very good correlation with a relative percent difference (RPD) of less than five 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 QA/QC analyses, it is concluded that the laboratory data generated for the second 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. M:\ 2014.0012\FA_2Q14.docx S 7/29/2014, Rev. 0