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® 2012 sampling event. The Highest VOC concentrations reported were the Xylenes, MtBE, TBA,the benzene compounds, and Toluene. The quantities of leachate indicate that the LCRS is able to maintain the level of leachate below regulatory limits. GROUNDWATER DIRECTION AND FLOW RATE The groundwater elevations indicate that groundwater flow is to the east during third and fourth quarter of 2012 (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 15.30 ft/yr in the third quarter and 19.23 ft/yr in the fourth quarter(Appendix G). STANDARD OBSERVATIONS Site inspections were performed weekly this semester(Included as PDF on CD). 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). The 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 were no breeches in any of the run-on/run-off facilities during this semester. These facilities will continue to be monitored. 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 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 2nd Semester and Annual 2012 Groundwater Monitoring 12 County of San Joaquin—January 15,2013