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Therefore, a hypothetical the release scenario includes: 1. Newly constructed cell is lined with geomembrane and subjected to construction quality assurance including liner leak detection after installation of operations layer over liner and LCRS. Penetrations detected during leak detection are repaired. 2. During placement of initial lift of waste over operations layer, heavy equipment operator inadvertently penetrates base geomembrane at the side of the landfill. Based on our experience in repairing such damage, the damage consists of rips and tears in the geomembrane that are usually less than 10 feet long. 3. Landfill gas escapes through the penetrations and ultimately carries VOCs to the groundwater. Hypothetical Corrective Action The following corrective action response was developed to mitigate the impacts envisioned under the hypothetical release scenario. The extent and complexity of the corrective action response is proportional to the environment threat of the release and is consistent with the type and magnitude of corrective action mandated by the RWQCB at the time this document was prepared. The corrective action envisioned is based on the following assumptions and premises: The focus of the corrective action is source control. 2 The low level release of VOCs to groundwater will not require active groundwater cleanup (pump and treat, air sparging, etc.). This approach is justifiable given the remoteness of the landfill and absence of surrounding residences. The performance objective of the corrective action is to primarily stop increases in VOC concentrations in groundwater and secondarily to reduce VOC concentrations in groundwater over time. Corrective action taken to mitigate the hypothetical release scenario will include the following activities: 1 A geoprobe investigation to estimate the location of the release will be conducted. This process of location will not be very exact and may be limited to identifying a suspect module. 2 Install nine additional LFG extraction wells designed to draw preferentially from deep within the waste. The wells will be located according to the apparent location of the release. Corrective Action Financial Assurance Cost Estimate 4 September 30, 2008 North County Recycling Center and Sanitary Landfill Public Works/Solid Waste Div.