ARCHIVED REPORTS_FIVE-YEAR WATER QUALITY REVIEW REPORT 11-17-2008

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Five-Year Water-Quality Report November 17,2008 Neenah Paper FR LLC Ripon Mill Page 16 of 19 As in the semiperched zone, groundwater in the upper zone moves to the northeast in the northeastern corner and to the southwest in the southwestern corner. Unlike the semiperched zone, however,there does not appear to be movement of water from the Stanislaus River into the upper zone. In the intermediate zone,the direction of the groundwater gradient is generally towards the southwest and northwest, defining a local groundwater divide(Figure 5). This is possibly a reflection of the groundwater mounding in the semiperched zone,but also may reflect groundwater mounding beneath the wastewater ponds to the west. GROUNDWATER QUALITY TDS Maps As with groundwater elevation,the effects of discharge at the site are shown most directly in the semiperched zone. Figure 6 shows a TDS-contour map for the semiperched zone for October 2007 (the same period as the groundwater elevation maps). Elevated TDS concentrations (>1,000 mg/L) occur beneath ASB-2, in the southwestern part of the site, and in the northeast corner of the site beneath the East Orchard. Elevated TDS beneath ASB-2 can be attributed to infiltration from ASB-2. The City of Ripon sewage ponds are located immediately west of the site and may contribute to the elevated TDS concentrations found in the semiperched zone in the southwest, along with application of process water on the upper west field. The area of elevated TDS in the northeastern corner of the site likely is attributable to uptake of water by the eucalyptus trees in that area,with the resulting concentration of constituents in the groundwater there. Figure 7 shows a TDS-contour map for the upper zone for October 2007. TDS contours in the upper zone show the highest concentration in the south-southwestern portion of the site and the lowest concentration in the southeast corner near the active pumping wells. This pattern reflects the movement of the high-quality SSJID water towards the active pumping wells in this area. Figure 8 shows a TDS-contour map for the intermediate zone for October 2007. The highest TDS values occur in the northeastern and eastern parts of the site, and decrease across the site from there. Unlike the semiperched and upper zones, TDS in the intermediate zone has not always been directly related to the direction of the groundwater gradient(e.g., higher TDS in areas of higher groundwater elevations). Previously,pumping wells in the intermediate zone showed higher TDS than monitoring wells, suggesting that pumping induced flow of lower-quality water from higher zones into the intermediate zone. Currently,however,the active pumping wells (PW-6, PW-7, and PW-8) have among the lowest TDS values (370, 570, and 530 mg/L, respectively) of all the monitored wells. 003044.02 Lawrence&Associates W:UientslFoxRiver-Neenahl5 year review reports15 Year Review 2008Weenah_SYearReview Aug2008.doc