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' 16 December 2005 • AGE-NC Project No. 04-1214 Page.7 of 8 1 4.3. ANALYTICAL RESULTS OF GROUND WATER SAMPLES VOCs were not detected in the ground water samples from the wells at Ripon Farm Service. ' Additionally, chlorinated pesticides, herbicides, ammonia and nitrates were not.detected in the groundwater samples collected from monitoring wells MW-101 through MW-104 at RFS. The pH values were normal for ground'water in the shallow alluvial areas. ' Analytical results are summarized in the laboratory report (CTEL Project No.: CT214-0510104) .included in Appendix D. Also included are quality assurance/quality control (QA/QC)reports,and the chain of custody form. 1 • 5.0. SUMMARY AND CONCLUSIONS Based on the data collected from the site, AGE finds: • The stratigraphy consisted of fine to medium silty sands and minor silt units above the water table with coarse poorly graded sands at a depth of 35 feet bsg, comprising a semi-confined • shallow aquifer. The ground water flow direction was inferred to be northeast at a low hydraulic gradient north of well MW-101. • Dissolved VOCs,chlorinated pesticides,herbicides,ammonia and nitrates were not detected in the ground water samples collected from the wells at Ripon Farm Service. The pH values were normal. The general lack of detection for the ammonia and nitrate in the four on-site monitoring wells, all ' completed within the first water bearing aquifer at the site,indicates that the Ripon Farm Service site is,not the main source for the regional nitrate detected in deeper screened domestic wells,including the on-site drinking water well. 6.0. RECOMMENDATIONS ' Based on the findings of the environmental activities recounted in this report and previous investigations, AGE recommends continuation of the quarterly ground water monitoring program; ' the next monitoring event is scheduled for January 2006. -As documented by multiple domestic wells in the vicinity of Ripon with excessive nitrate, ' concentrations, the regional-nitrate-impact (regional plume) to the primary drinking water aquifer should be further investigated through additional sampling of off-site shallow monitoring wells and ' Advanced GeoEnvironmental,Inc.