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® Water levels were measured during the 1St and 2nd Semester 2012,but the water levels were not sufficient to take a sample. G-6 (Down-gradient): All concentrations of field and monitoring parameters were below established concentration limits in G-6 during the 1St semester 2012. The concentration limit for Turbidity was slightly exceeded in G-6 during the 2nd semester 2012 sampling event. However,turbidity is not a parameter that is indicative of landfill impact to groundwater. VOCs VOCs were not detected in any wells during the 1St or 2nd Semester 2012. Prior to the second semester 2010 sampling event, VOCs have not been confirmed at the North County Sanitary Landfill since January 2003, over nine years ago. Storm Water Storm water was sampled from discharge point SW-4 at the north west corner of the Unit during the 1St and 2nd Semester 2012 (Appendix Q. Results were unremarkable. Surface Water Surface water samples were not available for collecting during the second semester 2012 sampling event. Surface water samples were last collected January 31, 2011. Samples are taken if sufficient water is flowing at sampling points during the wet season. Unsaturated Zone During the first and second semester,the lysimeters did not yield enough water for sampling, indicating no detectable leaks from the liner in those areas. Unsaturated zone monitoring will continue in accordance with the WDRs. Unsaturated Zone Soil Gas The Methane concentration was zero in all wells during the 1St and 2nd Semester except SG-6, where methane was reported at 26.7% during the 1St Semester 2012 sampling event. VOCs were reported in all samples collected this year. The number of VOCs reported per event varied from 30 in the first semester to 21 in the second semester. The number and type of VOCs reported does not indicate a trend. VOCs are typically not found in the groundwater. The presence of VOCs at these concentrations in the soil within the landfill property does not apparently impact groundwater. Leachate Results of leachate monitoring are consistent with past leachate monitoring events. The first semester leachate monitoring event occurred on January 9, 2012. Twenty Six different VOCs were reported during the 1St Semester 2012 sampling event. The Highest VOC concentrations reported were the Xylenes,MtBE, TBA,the benzene compounds, and Toluene. The second semester leachate monitoring event occurred on August 1, 2012. Twenty Eight different VOCs were reported during the 2nd Semester North County RC&SL Public Works/Solid Waste 2"d Semester and Annual 2012 Groundwater Monitoring 11 County of San Joaquin—January 15,2013