ARCHIVED REPORTS_FIRST QUARTER 2008 GROUNDWATER MONITORING REPORT

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Fox River Paper Company January 31,2007 Combined Annual and 4th-Quarter 2006 Groundwater Monitoring Report Page 8 of 9 Conclusions • The application of plant-process water for the irrigation of tree orchards and the potential infiltration from the process-water ponds and aeration basins, is thought to have caused groundwater mounding in the semiperched, upper, and intermediate aquifers (Figures 6, 7 and 8). Infiltration of plant process water is suspected to be responsible for the elevated conductivity levels measured in the semiperched aquifer(Figure 9). The sources of the elevated conductivity measured along the northern boundary of the property in the semiperched and upper aquifers are unknown at this time(Figures 9 and 10). Recommendations It is recommended that the CVRWQCB reduce the monitoring frequency at this site from quarterly to semiannual (once during the wet season and once during the dry season). This recommendation is based on previous analyses which indicate that groundwater quality beneath the site is relatively stable or only changing slowly through time as documented by fourteen years of quarterly groundwater-monitoring data. FR should begin the first phase of remedial action for the site, the importation and spreading of low TDS irrigation water in the east percolation field, during the 2007 irrigation season. Summary of work performed Depth to groundwater The depth to groundwater was measured in all wells prior to purging and sampling using an • Actat Model 300 electric well probe. The depth to groundwater was recorded to the nearest 0.01 foot(Table 4). Purging procedures All wells (except wells PW-4, PW-5, PW-6, PW-7, and PW-8, which have dedicated submersible pumps)were purged using either a submersible Grundfos MPI 2-inch pump or an Enviro-Tech ES-60 1.875-inch PVC pump set up to 20 feet below the surface of the groundwater. Prior to sampling, each well was purged of three casing volumes of water or until field parameters stabilized. Purged water from wells TH-7 through TH-10 and wells M- 7-A, M-11-A, M-11-C, and M-19-C were transported to Nestles' water treatment system in Ripon for disposal because TCE or various TCE daughter products have been detected in these wells. Purged water from all other wells was disposed by direct discharge to the ground surface and allowed to infiltrate/evaporate. Sample collection Groundwater samples were collected directly from the discharge pipe from the submersible pump. The samples were stored on ice in a cooler, and delivered under chain-of-custody to BC Laboratories, Inc. in Bakersfield, California for analyses. Field analyses Field analyses for temperature, conductivity, and pH were performed on groundwater samples using a Cole-Parmer portable pH/conductivity meter (model number 19825-00). Turbidity measurements were performed on groundwater samples using a Cole-Parmer turbidimeter • (model number A391-50; Table 4). 005194.00, Task 8 Lawrence&Associates W:IC(ientsIFoxRiverlQuarter[yMonitoring1200614Q200614th 2006reportdoc