SITE INFORMATION AND CORRESPONDENCE

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Three Former Vapor Extraction Wells October 12,2010 Former Nestle USA,Inc.Facility,Ripon,CA • Fall 2008: The current property owner installed a concrete driveway over an area formerly occupied by a narrower asphalt driveway. The new concrete driveway was wider than the older asphalt driveway, and therefore extended into a landscaped area. This landscaped area was the former location of VE-11,though VE-11 was not located at the time. • Spring 2009: ECM hand excavated in the landscaped area near former VE-11 to approximately 3 feet below ground surface (bgs) and found shattered PVC VE laterals. ECM searched the entire landscaped area with a metal detector and traced along the PVC laterals throughout the landscaping, hand-excavating along the way, but did not locate VE-11. • September 30, 2009: ECM notified SJC-EHD about the three missing VE wells while preparing permits to decommission eight other VE wells. SJC-EHD requested more research, preferably in the form of a Ground Penetrating Radar(GPR) survey. • February 19, 2010: A geodetic (land) survey was completed by Subtronic Corporation in an attempt to locate the three missing VE wells. The former well locations were identified using historic survey data from a licensed surveyor and a known (current) well point as a lateral reference. Once the land survey locations were established, a GPR survey was completed by Subtronic using a GSSI SIR-3000 and a Schondstedt GA-72-CD, which can accurately detect to a depth of 10 feet bgs and receives reflected radar waves directly above any anomaly, thus creating little to no lateral imprecision. The GPR survey was completed in a 25-foot by 25-foot grid encompassing each of the three survey locations. The GPR survey indicated radar anomalies of unknown material at approximately 18 inches bgs within one-foot of the surface well survey points for both VE-11 and VE-12. No visible radar disturbance was identified in the vicinity of the surveyed location of VE-4; however, Subtronic reported a GPR anomaly next to VE-4. The GPR locations were marked on the ground and photographed for future investigation. The eastings and northings of the survey points were also recorded. r� From left to right, GPR/survey locations for VE-11, VE-12, and VE-4, facing north/northwest towards Hwy 99 overpass. This photograph was taken prior to the installation of a new fence in May 2010. The new fence runs east-west from VE-11 along the concrete driveway and overtop of the location of VE-12. 2