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not detected in the water samples taken in MW -3. MW -3 continues to show no impact by VOCs. The volatile organic compounds (VOC) have been confirmed in groundwater at well MW -3 and the VOCs that are most prevalent are Trichloroethene (TCE) and 1,1-Dichloroethene (1,1-DCE). TCE had eleven quantified detections with a maximum concentration of 4.0 micrograms per liter (g/1) and an average concentration of 0.78 g/1. l,l-DCE had six quantified detections with a maximum concentration of 0.32 g/1 and an average concentration of 0.16 g/l. 1.2.3 Run-off/Run-on Facilities Foothill Sanitary Landfill utilizes several methods to control run-on and run-off. The natural topography of the area controls run-off and run-on into the site. Run-on from surrounding properties is minimal due since the working area is a significant distance form the property boundary. The facility utilizes drainage channels along the landfill perimeter to handle storm water runoff from Module I. The channels discharge into sedimentation/detention basins for sediment control, and to reduce stormwater flows off site. 1.2.4 Containment Systems Module I is unlined and therefore does not have a leachate collection and recovery system (LCRS). Module 1 is lined with a 60 mil HDPE geomembrane with an overlying LCRS. Recovered leachate is applied to the waste surfaces or travel surfaces within Module 1. The recovered leachate is at no time applied to Module I. Module 1 is fitted with a geomembrane base liner and LCRS. Future expansions will have the same or better containment systems. Module I, on the other hand, has no base liner. For this reason, Module I has a higher probability of a release and is therefore assumed to be the source of the hypothetical release. Historic monitoring provides evidence of groundwater impacts due to landfill gas migration but monitoring data does not indicate a large release of inorganic constituents (as would be seen with leachate escaping from the bottom of the landfill). Module I is undergoing partial closure in 2006, which further reduces the chance of leachate generation. Using past performance of the module as an indicator of possible future release mechanisms, escape of landfill gas from the module is more likely than generation of leachate as a mechanism for moving contaminants from the bottom of the landfill to groundwater. 73467 3 August 9, 2006 LA 31109 Corrective Action Financial Assurance Cost Estimate Foothill Sanitary Landfill