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The sump pump within Module 4 operates automatically, pumping leachate based on leachate levels within the sump. Control points for the leachate sump pump are: Action Indicated Depth inches Actual Depth inches Pump Off: 8 32 Pump On: 18 42 High Level Alarm: 24 48 The leachate pump intake is located 24 inches above the floor of the sump to avoid pulling soil from sump into the pump. Operation of the Module 4 pump is conditional upon sufficient water in the sump (indicated by the level sensor on the pump) and available capacity in the Module 4 leachate tank (indicated by the float switch in the tank). The high-level sump alarm is set to alarm at the upper lip of the sump, thus alerting the operators before the one -foot leachate limit is exceeded at the Module floor beyond the sump. Normal operation of the leachate system at the North County Landfill calls for leachate to be pumped directly from the Module 4 sump to the refuse at a diffusion point. Leachate may also be pumped to the 10,000 -gallon storage tank near Module 4 prior to return to the landfill. From the leachate tank, leachate can be removed either by the return pump (which returns leachate to the refuse) or by the transfer pump (which pumps into a water truck, that truck used to transfer the leachate to the refuse). Under low-level conditions in the tank, the return pump and transfer pump are deactivated, preventing the operation of these pumps with insufficient fluid. Under high-level conditions in the tank, an alarm will activate and the leachate sump pump will be deactivated, preventing overflow of the tank. Ell 0 Testing the leachate system consists of monitoring the pumping rate of each sump pump, and comparing that data to past performance. Flow rate is calculated by the operator while observing the flow meter. Leachate pumps that are operating at the rate consistent with past performance are considered to be operating normally. The liquid level in the secondary sump of Module 4 is measured by "bubbler tube" once quarterly. The level was first measured in the last quarter of 2009, and was found to be 0.5 inches. This small amount of water, accumulated since installation in 2004, is consistent with condensation, and does not indicate a liner leak. Module 1-3 LCRS Pump Control Upgrade 3 North County Recycling Center and Sanitary Landfill May 26, 2010 San Joaquin County