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i Leachate was sampled at collection point L-1, L-3, and L-4 (Table 5). Twenty Five different VOCs were reported in the leachate samples. The highest VOC concentrations reported were the Xylenes, MtBE, TBA,Acetone,the benzene compounds, and Toluene. Results are consistent with past leachate monitoring events. Presence of VOCs in the leachate does not indicate groundwater contamination, but rather the success of the liners at North County Landfill in preventing groundwater contamination. Secondary Sump Monitoring The liquid level in the secondary sumps of Area 3 and 4 are monitored quarterly. No liquid was found in either secondary sump since monitoring began in July 2010. This lack of liquid indicates that the primary liners are not leaking. Area 1 is not provided with a secondary Sump. * GROUNDWATER DIRECTION AND FLOW RATE ■ The groundwater elevations indicate that groundwater flow is to the south-southeasterly direction during first and second quarter of 2014 (Figures 3 and 4). These are unusual groundwater flow conditions, as flow is historically in a westerly direction. It appears that starting in 2009 the regional flow pattern has shifted to the south-southeasterly and sometimes to the easterly direction. This change in flow direction may be due to changes in regional agricultural groundwater pumping. The average calculated groundwater velocity is 26.93 ft/yr in the first quarter and 19.24 ft/yr in the second quarter (Appendix G). STANDARD OBSERVATIONS Site inspections were performed weekly (Included as PDF on the CD, attached). An electronic signature on the form certifies that all observations were performed and are accurate. RUN-OFF/RUN-ON FACILITIES The NCRC&SL utilizes several facilities to control run-on and run-off. A perimeter berm around the waste management unit prevents any run-on to the unit. This perimeter berm, along with a series of ditches, also controls all surface run-off during storm events, and directs surface run-off from the landfill to a retention basin on the east side of the site (Figure 3). lThe primary path for water entering the site is from a tributary of South Paddy Creek east of the site. Water entering from this source is diverted into the wetlands on the north end of the site and around the unit(Figure 3). There was no run-on or run-off during this monitoring period. LEACHATE COLLECTION AND RECOVERY SYSTEM Leachate is collected in the Leachate Collection and Recovery Systems (LCRSs) of the three landfill Areas. This leachate is returned to the refuse in accordance with the WDRs for this site. Landfill gas I condensate is pumped into the LCRS of Area 4, and is handled as leachate also in accordance with the WDRs. The semi-arid climate of the North County Landfill and the waste shed from which the refuse is collected provides dry refuse in which the leachate can be absorbed. North County RC&SL Public Works/Solid Waste 15`Semiannual 2014 Groundwater Monitoring 8 County of San Joaquin—July 31,2014