SITE INFORMATION AND CORRESPONDENCE

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Mr. Mike Desso - 2 - • 8 May 2008 Nestle USA Inc. (up to 7,800 pg/L) and largest lateral extent of dissolved TCE occurs between approximately 50 and 65 to 70 feet beneath ground surface (bgs). The other sand layer is less extensive, is between approximately 30 to 45 feet bgs and has TCE concentrations up to 2,500 µg/L. The primary objectives presented in the IRAP were to stop continued migration of VOCs in shallow groundwater away from the Former Facility and to reduce dissolved concentrations of VOCs in groundwater. The IRAP presented an evaluation of four methods to achieve the objectives, and selected groundwater extraction and treatment from the sand layers within the upper zone onsite. To accomplish this, The IRAP proposed to modify an existing treatment system that ECM operated at the Former Facility. Two groundwater extraction wells, screened deeper than the targeted sand beneath the Former Facility were proposed to be replaced by two extraction wells screened within the sand. Treated water would continue to be conveyed to the City of Ripon wastewater treatment plant. The Work Plan proposed to install and develop two groundwater extraction wells (EU-3 and EU-4) and four groundwater monitoring wells (M-46A, M-47A, M-48A, and M-49A) screened within the sand layer identified in the IRAP as the layer containing the largest mass of dissolved TCE. The screens were to be placed between approximately 50 and 60 feet bgs. Also, the Work Plan proposed aquifer testing by performing pumping tests on the newly installed groundwater extraction wells. Following aquifer testing, remediation system modifications were to be made; the existing extraction wells EW-1 and EI-1 were to be taken offline and the new extraction wells placed online. A startup and prove-out sampling schedule was proposed for the first month of system operation; influent, intermediate, and effluent discharge samples were to be collected daily for the first week and weekly for the remainder of the month; after the first month, the Work Plan proposed monthly influent and bimonthly intermediate and effluent sampling of the system discharge. Well Installation and Aquifer Test Report On 20 December 2007, ECM completed installation of four groundwater monitoring wells and two extraction wells. All four of the monitoring wells were screened within sandy material between 50 and 60 feet bgs. Both extraction wells were screened within sandy material between 50 and 65 feet bgs. Between 7 January and 10 January 2008, ECM performed aquifer tests on the new extraction wells. By conducting step-drawdown tests, ECM established a constant pumping rate of 42 gallons per minute (gpm) for extraction well EU-4. After 20 hours of constant rate pumping at 42 gpm, the drawdown measured in EU-4 was 2.72 feet. Maximum drawdown in monitoring well M-47A, located approximately 18 feet from the pumping well was 0.57 feet. Also, drawdown in monitoring well M-1 B, located approximately 19.5 feet from the extraction well was up to 0.5 feet. Well M-1 B is screened in the sand layer above the targeted sand layer. By conducting step-drawdown tests, ECM established a constant pumping rate of 60 gpm for extraction well EU-3. After 20 hours of constant rate pumping, the drawdown measured in EU-3 was 19.9 feet. Maximum drawdown in monitoring well M-46A, located approximately 54.3 feet from the pumping well was 0.63 feet.