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in accordance with CCR Title 27, Section 20937, Forward continues to install additional landfill gas extraction wells, as needed. Concentration Limit Thresholds As specified in the RPCMP and RWQCB Order No. R5-2003-0049 for the Forward Landfill, the routine inorganic monitoring data obtained during the fourth quarter 2013 monitoring period were compared to established intrawell concentration limits (CLs) calculated for the Forward Unit. The CLs are summarized in Table 2-4 and compared to the analytical results collected during the fourth quarter 2013. As summarized in Table 2-4,the following CLs were exceeded during the fourth quarter 2013 monitoring period. • Chloride at wells MW-2A and MW-13 • Nitrate-N at wells MW-14 and MW-23R • Sulfate at wells MW-14,MW-15, and -23R Trend analyses were performed for wells and constituents that exceeded respective CLs. Statistically significant increasing trends were identified for chloride concentrations in well MW-2A, nitrate-N concentrations in well M -14, and sulfate concentrations in well MW-15. Trend analyses are included in Appendix D. The increasing trends in wells MW-2A,MW-13, and MW-15 appear to coincide with the groundwater gradient reversal in the northeast corner of the landfill since the Spring of 2011. Vadose Zone Monitoring The current vadose-zone monitoring network at the Forward Unit consists of 17 lysimeters. The lysimeter locations are shown on Figure 2-1. As recorded in the field notes for lysimeters (Appendix C) and summarized on Table 2-5, lysimeters were reported dry, and as a result,no soil-pore liquid samples were collected during the current monitoring period. Of note, there was no access port to inspect pan lysimeters WMW- DO1N,WMW-DOLS, and WMW-D02. GLA and Del-Tech will be working with Forward to access these pan lysimeters for future monitoring. Leachate Monitoring Leachate sumps are inspected for the presence of leachate and observations are recorded at least weekly by Forward Landfill personnel. If leachate is detected in a sump, it is pumped into the surface impoundment(WMU F)for evaporation. During the fourth quarter 2013, leachate was observed at all of the holding areas except WMU D-87 and WMU D-88 A/B. Freeboard at WMU-F ranged from approximately 3.25 to 8.50 feet during the fourth quarter 2013 monitoring period. Appendix A presents copies of the leachate logs and the freeboard observation logs. Leachate samples were collected on a monthly basis and analyzed in the field for pH, specific conductance,temperature, and turbidity. In addition to monthly monitoring, leachate is sampled annually during the fourth quarter monitoring period for the c:U013.0021Wn_4Q13.aa 6 Geo-Logic Associates