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743 Kearney Street, 4VALUE Benicia, CA 94510 Phone:707.771.9009 ENGINEERING Fax :707.747.9996 August 31, 2010 Mr. Don Litchfield Environmental Manager Forward Landfill 9999 S. Austin Road Manteca CA 95336 Forward Landfill Inc.Evaporation Basin MMU F) Leachate Collection and Recovers,System (LCRS) Gas Test Dear Mr. Litchfield: On August 27,2010,Value Engineering conducted an LCRS Gas Test at the 1.0 acre Evaporation Basin at the Forward Landfill in Manteca, California. Attached with this letter are the results of the test.The test conducted was a Pass indicating that an open-air conduit is present across the LCRS unit. The test consists of injecting a high concentration of sulfur hexafluoride gas into the far side of the LCRS system and allowing the gas to migrate through the unit to settle in the low point of the LCRS sump. The non-toxic sulfur hexafluoride gas is heavier than air that allows it to migrate to the lowest point of the sump. Once the gas has migrated through the system, it can be extracted and detected from the sump extraction pipe indicating that an open-air conduit is present through the unit. if excessive liquid is backed up into the drainage layer of the LCRS, the gas will not be able to migrate to the sump. If a significant amount of liquid is in the LCRS sump, the liquid will block the sump extraction pipe and no gas can be extracted or detected from the system.Prior to the test, your staff was requested to pump all liquids from the LCRS sump. The LCRS gas test is a qualitative test and determines if an open-air conduit exists through the unit and if liquid present in the sump is blocking the sump extraction pipe. If gas is extracted and detected,the test passes. If no gas is detected from the LCRS swop the test fails. The test is conducted in two phases: the Gas Injection phase, and the Gas Detection phase. Alt testing information was recorded on the attached LCRS Gas Testing Form. 1 www.valuengineering.us