ARCHIVED REPORTS_FIRST-HALF 2010 GROUNDWATER MONITORING REPORT 07-27-2010

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Neenah Paper,Inc. July 27,2010 First-Half 2010 Groundwater-Monitoring Report Page 3 of 7 irrigation water had the additional benefit of creating a hydrologic barrier between ASB-2's TDS plume and the production wells. Improving the quality of water in the vicinity of the production wells ultimately improves the quality of water discharged by the mill as effluent. According to L&A's groundwater model, the infiltration of 67 acre feet of water annually to the east percolation field, over a five year period, will bring TDS levels in the semiperched and upper aquifers into compliance with the site's WQPS. Groundwater quality improved in the immediate vicinity of the east percolation field in the semiperched, upper, and intermediate aquifers following the application of SSJID water.3 The third season of applying low TDS water to the east percolation field began on August 3, 2009, and ended on September 23, 2009. A total of 21.77 acre feet (7.1 million gallons) of water from production well PW-6 were placed on NP's east percolation field. First-Half 2010 Groundwater Monitoring Findings, first-quarter 2010 First-quarter 2010 groundwater levels were measured on January 11, 2010, and are presented in Table 3 (following text). Mounding was present within the semiperched aquifer in the vicinity of wells OB-9 and OB-18. The direction of the semiperched gradient was away from the mound then generally towards the northwest at magnitudes ranging between 0.002 and 0.00084 feet/foot (ft/ft; Figure 3). Mounding was present within the upper aquifer in the central and southeast corner of the site. The direction of the gradient was away from the mound then generally towards the northwest at magnitudes ranging between 0.001 and 0.00094 ft/ft(Figure 4). Mounding was present within the intermediate aquifer north of the City of Ripon MWWTF and in the vicinity of Neenah monitoring well TH-11; additionally, the influence of production well PW-6 was evident from the depression of the groundwater gradient in the southeastern corner of the site as well as the Nestles' extraction system on Stockton Avenue. The magnitude of the gradient ranged between 0.002 and 0.0027 ft/ft(Figure 5). Findings, second-quarter 2010 Second-quarter 2010 groundwater elevations were measured on April 5, 2010, and groundwater samples were collected between April 6 and 7, 2010. Field and laboratory results are presented in Table 4 (following text). The direction of the semiperched aquifer groundwater gradient was generally towards the northwest at a magnitude of 0.0013 ft/ft(Figure 6). The direction of the upper aquifer groundwater gradient on April 5 was generally towards the northwest at a magnitude of 0.0011 ft/ft(Figure 7). The direction of the intermediate aquifer groundwater gradient was generally towards the northwest at magnitudes ranging between 0.00032 and 0.00043 ft/ft(Figure 8). The areas of highest Specific Conductance (SC) in the semiperched aquifer were in the northeast quadrant of the NP site in well OB-4 (2,438 µmhos/cm), along the northwestern property boundary in the City of Ripon's monitoring well MW-7 (2,038 µmhos/cm), adjacent to 3 L&A,February 8,2008, Combined 2007 Annual Summary Report, 4th-Quarter 2007 Groundwater-Monitoring Report,And Preliminary Corrective Action Evaluation,Neenah Paper Company,Ripon, California. 005194.04 Task 4 Lawrence&Associates W.•I CLIENTSIFoxRiver-NeenahlQuarterlyMonitoringl201011st half 2010 reporkdoc