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Inspection Report 21 November 2014 Foothill Landfill San Joaquin County The M-2A area, formerly operated as a borrow area, was several feet below natural grade. M-2A's containment system will tie into M-1's liner along a lower side slope bench (used as an access road) currently separating the two areas. See Photo 13. M-2A's LCRS sump will be constructed in the southeast corner of the M-2A area north of a planned drainage basin. The M-213 area will be used as a staging area during M-2A construction. I informed the Discharger that I had received, and was currently reviewing, the design report for M-2A. Landfill Gas Controls Landfill gas (LFG) is extracted from the landfill modules by vertical wells at Module I and horizontal wells at Module 1. Lateral and header piping then conveys the gas to a gas-to- energy plant in the southeast corner of the site. At the plant, the gas is converted to electricity and exported for commercial use. Prior to start-up of the gas-to-energy plant, the gas had been flared at a nearby LFG flare station. Condensate removed from a knock-out sump in the gas-to- energy plant and condensate removed from a knock-out sump in the header pipe near the flare station are pumped back to Module 1's LCRS sump via separate lines. See Photos 14 through 16. Other Areas We also viewed the long term borrow area west of Module 1 where the Discharger obtains cover soil for landfill operations and construction. The top soil in the area had been removed, exposing a variety of sedimentary rock units containing cobble, quartz, conglomerates, clay, silt, and black sands. The Discharger indicated that because the landfill unit is being developed in a counterclockwise sequence, it will be many years before the borrow area is developed into a landfill module. We also viewed the locations of the down gradient groundwater monitoring wells along the southern site perimeter (MWs-5 and 6). See Photos 17 and 18. We left the site at about 12:30 p.m. CONCLUSIONS: 1. Overall the landfill units appeared to be in good condition and repair. A few maintenance/repair issues were noted, however, including unvegetated upper slopes on the east side of Module 1 and rodent burrows and a thin crack in the ET cover on top of Module L 2. All landfill control systems observed during the inspection (i.e., leachate, landfill gas and storm water) appeared to be functioning and/or functional at the time of the inspection. 3. A follow-up inspection of the site during wet season conditions is recommended to evaluate the functionality of the facility's storm water controls and drainage systems. 4. Assuming Module I is a separate landfill unit under Title 27 regulations, as discussed during the inspection, it will need to comply with Title 27 requirements applicable to waste management units (e.g., water quality protection standard, closure). For example, Module I would need to have its own groundwater monitoring system, including a Point of Compliance well directly down gradient of the landfill between Module I and Module 1. The unit would also likely need to be closed, since it is no longer accepting waste. Required - 3 -