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Water Quality Monitoring Report Forward Landfill where: V = Groundwater flow velocity. K = Hydraulic conductivity of the water -bearing unit (0.04 cm/sec). i = Hydraulic gradient: i,& 0.001 to 0.003 at the site during the fourth quarter 2014. ne= Effective porosity (ne = 0.35); an estimated value. The estimated groundwater flow rate is calculated to be 0.324 to 0.972 feet/day (118 to 355 feet/year). 3.1.4 Detection Monitoring Program Field and laboratory results for the Austin Unit DMP wells for the fourth quarter 2014 are summarized in Table 3-1. Non -Statistical Data Analysis During the fourth quarter 2014 monitoring period, the CNSDAM was performed for VOCs detected in the DMP wells. As shown in Table 3-1, non -statistical indications of a release were identified at well AMW-6 as a result of a quantifiable concentrations of dichlorodifluoromethane (DCDFM), tetrachloroethene (PCE), and a trace -level detection of trichloroethene (TCE). In a letter dated October 1, 2014, the RWQCB was notified of these exceedances during the third quarter 2014. Forward had previously requested that well AMW-6 be reclassified as a CAP well, since historically similar concentrations have been measured in this well. There were no other VOCs detected in DMP wells for the Austin Unit. Concentration Limit Thresholds In accordance with RWQCB Order No. 115-2014-0006, the routine inorganic monitoring data obtained from the Austin Unit DMP wells during the fourth quarter 2014 monitoring period were compared to intrawell CLs established for each well. As discussed in Section 2.1.4, CLs are updated annually and the updated CLs are presented in Table 3-3. As summarized in Table 3-3, no CLs were exceeded during the fourth quarter 2014 monitoring period. A discussion of the CL statistical methods is included in Appendix G. During the third quarter 2014, CL exceedances were noted for wells AMW-6 and AMW- 7. Retest results were not confirmed for well AMW-7 and AMW-6 was not retested since this well was to be reclassified as a CAP well in the new WDR. 3.1.5 Corrective Action/Evaluation Program Field and laboratory results for CAP and EMP wells for the fourth quarter 2014 monitoring period are summarized in Table 3-2. As shown in Table 3-2, 17 of 28 CAP/EMP wells reported one or more VOCs exceeding a Practical Quantitation Limit M:\ 2014.0012\FA_4Q14.docx 11 1/28/2015, Rev. 0