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Mr. Mike Desso • - 3 - Is 8 May 2008 Nestle USA Inc. Pumping test and aquifer data were analyzed to estimate hydraulic aquifer parameters using both the Theis (1935) and Hantush-Jacob (1955) methods. The Theis analyses estimates for hydraulic conductivity for both extraction wells was approximately 2.5 x 10 ' centimeters per second (cm/s) and the Hantush-Jacob analyses estimates for both was approximately 1.5 x 10-' cm/s. Laboratory chemical analyses were performed on groundwater samples collected during the constant rate pumping tests. Concentrations of TCE in extraction well EU-4 ranged from 1,500 micrograms per liter (µg/L) at the start of the test to 1 ,200 gg/L at the end of the test. In extraction well EU-3, the concentrations ranged from 570 lag /L at the start to 710 µg /L at the end of the test. ECM utilized the pumping test results and the groundwater model for the site (developed in 2007) to predict flow paths and capture zones that may be achieved by pumping the new extraction wells. Based on the modeling results, they proposed pumping rates that are expected to achieve capture of the TCE plume migrating from the Former Facility in the shallow aquifer. They proposed an operational pumping rate for both extraction wells of 30 gpm. During January and early February 2008, ECM installed the treatment system piping and components necessary to bring new extraction wells EU-3 and EU-4 online with the groundwater extraction system and to take EW-1 and EI-1 offline. Groundwater Extraction System Startup Report On 14 February 2008, ECM conducted startup of the modified groundwater extraction system utilizing new extraction wells EU-3 and EU-4. During the first week of operation, water samples and system parameter data were collected daily from the treatment system, and groundwater measurements and samples from 6 nearby monitoring wells were collected at the end of the week. During weeks 2, 3, and 4, water samples were collected at the end of each week from the treatment system, and at the end of week 4, from the 6 monitoring wells. Starting with the second month, system influent samples were collected monthly, and system mid-point and effluent samples were collected twice per month. Analysis of drawdown data collected from the extraction system wells and monitoring wells during the first 5 weeks of operation show similar results to the data collected during the aquifer pumping tests. This suggests that pumping both new extraction wells at 30 gpm may be capturing the onsite TCE plume. Also, drawdown data collected from monitoring well M-1 B screened in the upper sand layer above the sand layer being pumped by the extraction wells suggests that TCE in that layer is being captured. The concentrations of TCE in ten combined EU-3 and EU-4 system influent samples collected between startup on 14 February and the end of week 5 on 18 March declined from 920 µg /L to 260 µg /L, and seems to be leveling off at approximately 200 gg /L. On the other hand, concentrations of TCE in monitoring wells have only fluctuated slightly over the same period, with the exception of up-gradient, onsite well M-46A which increased from 80 µg /L at startup to 520 µg /L at the end of week 4.