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L Austin Unit - In 1989 a Solid Waste Assessment Test (SWAT) performed for the Austin Unit, found significant VOC impacts to groundwater downgradient of the Austin Unit. During the 2013 monitoring year VOCs continue to be measured at quantifiable concentrations in several monitoring wells. An Engineering Feasibility Study (EFS) performed for the Austin Unit indicated that the primary source of the VOC impacts to groundwater was from landfill gas. In response to the VOC impacts to groundwater at the Austin Unit, Forward submitted a CAP to mitigate VOC impacts to groundwater downgradient of the Austin Unit. The CAP was approved by the RWQCB in June 1991 and the groundwater treatment facility (GTF) began operations in 1994. Since 1998, groundwater impacts have been identified up to 4,000 feet downgradient (northeast) of the landfill and appears to have migrated to a lower depth at the leading edge of the plume. With the exception of well A -1, trend analyses indicates statistically significant decreasing or static trends for VOCs measured in CAP wells, suggesting that the current corrective action measures have been successful in reducing facility related groundwater impacts downgradient of the Austin Unit. 2.4 Surface Water Hydrology The South Fork of Littlejohns Creek flows within confining levees in a southwesterly direction along the southern edge of the Forward Unit and along the south side of the southern expansion area of the site. Similarly, the North Fork of Littlejohns Creek flows southwesterly along the northern side of the Austin Unit. The majority of flow from these drainages is from the surrounding agricultural activities and occurs during and after relatively heavy periods of precipitation. Within the Forward Landfill, site run-on and runoff is channeled to on-site storm water/sedimentation ponds. 3.1 Landfill Gas Monitoring The LFG migration monitoring network at the Forward Landfill consists of 29 perimeter soil - pore gas monitoring probes (Figure 1), which were installed to monitor and fulfill regulatory standards for subsurface migration, as required by the applicable local, state, and federal regulations (e.g., CCR27, Section 20925). Generally compliance levels (5% methane) in perimeter soil -pore gas probes have not been exceeded. In the event that compliance levels are exceeded, Forward Inc. makes regular adjustments to the landfill gas extraction system to optimize efficiency of the landfill gas extraction system and continues to install additional landfill gas extraction wells, on an as needed basis. D:\2014-0012\FA finassur.doa 4 3/10/2014, Rev. 0