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Mr. Mike Desso • - 3 - • 15 September 2008 Nestle USA Inc. Concentrations of COCs have been reported in the domestic well depicted on Figures 9, 10, and 11 of the Annual Report on the north side of Mid Canal'Road`, approximately 1,630 feet southeast of monitoring well M-38C and 1,170 feet=Souttiwesf of monitoring well M-32C. The domestic well is screened within the Intermediate Aquifer and the concentration of TCE on 8 May 2008 was 10 µg/L. Therefore, it is reasonable to assume that the 0.5, 5.0, and 10 µg/L TCE concentration contours on Figure 9 extend from the wastewater ponds, across the river, and beyond the domestic well. Nestle should include the 8 May data on the figure and redraw the concentration contours accordingly. The concentration of cis-1,2-DCE on 8 May 2008 was 23 µg/L in the domestic well. Therefore, it is reasonable to assume that the 0.5, 5, and 10 µg/L cis-1,2-DCE concentration contours on Figure 10 extend from the wastewater ponds, across the river, and beyond the domestic well. Nestle should include the 8 May data on the figure and redraw the concentration contours accordingly. The concentration of vinyl chloride on 8 May 2008 was 5.4 µg/l- in the domestic well. Therefore, it is reasonable to assume that the 0.5 µg/l- vinyl chloride concentration contour on Figure 11 extends from the wastewater ponds, across the river, and beyond the domestic well. (The 5 µg/L contour was not included on the figure.) Nestle should include the 8 May data on the figure and redraw the concentration contour accordingly. Nestle should record the presence or absence of water in City and Neenah Paper Company (Neenah) ponds during quarterly monitoring events. Also, Nestle should obtain data on the time and duration that water was present in each pond throughout each quarter. In addition, Nestle should indicate which of the ponds were dry on the groundwater surface contour maps presented in the Annual Report. This may allow Nestle to understand the nature of COC transport in groundwater within the Upper and Intermediate Aquifers away from the ponds. These data should be included in future annual reports. 4. City Municipal Well MW-9. As you know, in April 2003 Nestle entered into an agreement with the City. One of the conditions of the agreement was that the City would maintain pumping (with carbon filtration) of water from municipal well MW-9, screened within the Intermediate Aquifer. The City has pumped, on average, approximately 420 gallons per minute from MW-9 since the agreement was initiated. Concentrations of the COCs TCE and cis-1,2-DCE in municipal well MW-9 appear to have declined somewhat over the last decade. However, over two periods each lasting seven months during which time the well was not operated, concentrations of both CDCs rebounded somewhat. The first period lasted from September 1997 through March 1998, and the second period from July 2004 through January 2005. While the pumping of MW-9 appears to have resulted in declining concentrations of CDCs in the Intermediate Aquifer, Nestle cannot show the effect it has had on the piezometric surface, and as a result, the area of COC capture. Nestle should install a sufficient number of monitoring wells near MW-9 to evaluate the effect that pumping has on the plume migration.