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Inspection Report ® 21 November 2014 Foothill Landfill San Joaquin County modules where Module 1's side slope liner was anchored. The Discharger plans to fill further up the southern slope of Module I, but would like to do so without having to install an impermeable barrier layer, which was required in the previous phase as part of the 2006 Site Improvement Program. This issue will need to be addressed in the updated WDRs. See Photo 6. Later in the inspection (after viewing Module I and the gas control facilities), we drove up a service road along the eastern side of the site to view the module's leachate handling facilities. The module's leachate collection and recovery system (LCRS) sump is located in the southeast corner of the module. Leachate levels in the sump are continuously monitored by sensor equipment in an instrumentation riser and the sump is automatically pumped down to a minimum level by a dedicated, submersible pump installed in main LCRS riser. Leachate volumes pumped are recorded at a meter station at the sump. Liquid pumped from the sump is then either re-injected back into the unit at two infusion points near the top of the module or pumped to a 10,000 gallon leachate storage tank near the LFG flare station for later application to M-1 (i.e., infusion and/or dust control) depending on needs. The LCRS is also equipped with a secondary sump (i.e., a trench) that is monitored using a bubbler line. A small amount of leakage from the overlying sump (e.g., 300 gallons) usually occurs each year and is automatically pumped back into the primary sump. See Photos 7 and 8. Module Next we visited Module I, which is unlined. The module stopped accepting wastes in 2004 and was partially closed with an evapotranspirative (ET) cover on the top deck under the 2006 Site Improvement Program. The Discharger pointed out a rectangular, bermed area where the ET demonstration project had been conducted. See Photo 9. The ET cover generally appeared to be in good condition, except for a couple of maintenance issues (e.g., small rodent burrows, cover crack). The side slopes of the module had well established vegetative cover. The drainage controls for the module, including top deck berm and overside drains, also appeared to be functional and in good condition overall. This module drains to the unlined storm water pond east of the site. See Photos 10 through 12. 1 mentioned to the Discharger that a preliminary review of Title 27 regulations indicates that Module I is a separate landfill unit from Module 1 because it pre-dated Chapter 15 regulations. Module I therefore appears to be an "existing unit" under Title 27 regulations, while the expansion landfill modules (M-1. M-2 etc.), comprise a "new unit" under Title 27. (This distinction is important because as a separate unit, Module I would need to have its own groundwater monitoring system.) I also indicated that the tentatives will likely refer to expansion areas as modules, as-imthe current WDRs. We drove along the access road separating Module 1 and Module I to look for compliance monitoring wells immediately down gradient of Module I. This access road between the two modules is approximately 20 feet wide. No groundwater monitoring wells were observed in this area. See Photo 6. Module 2 Area We also viewed the area south of Module 1 where the Discharger plans to construct the next landfill expansion module, Module 2. The Discharger plans to construct the module in two phases -- Module 2A (M-2A) in the spring 2015 and Module 2B (M-213) about three years later. - 2 -