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Work Plan For Soil Boring and Monitoring Well Installation,City of Ripon/Madsen Sunrise Dairy,Ripon,California December 2,2010 In Geoprobe GP-4, no detectable concentrations of TPHd were detected in samples GP-4-25 and GP-4- 29. TPHd was detected in samples, GP-4-5 and GP-4-10 at concentrations of 880 ppm and 9.9 ppm, respectively (reported by the lab to be higher boiling point hydrocarbons than typical diesel fuel). In sample GP-4-15, TPHd was detected at 2.4 ppm. In sample GP-4-19.5, TPHd was detected at 1.5 ppm (reported by the lab as discrete peaks in the diesel range). Groundwater samples collected from Geoprobes GP-1 through GP-4 did not contain detectable concentrations of TPHg, except for GP-3-W, in which a concentration 75 parts per billion (ppb) of TPHg was detected (reported by the lab as compounds not found in typical gasoline). TPHd was detected in groundwater samples GP-1-W, GP-2-W and GP-3-W at concentrations of 430 ppb, 260 ppb, and 420 ppb, respectively (reported by the lab to contain discrete peaks and higher boiling point hydrocarbons atypical for diesel). Groundwater sample GP-4-W, showed a concentration of 1,600 ppb diesel (reported by the lab to be higher boiling point hydrocarbons than typical diesel fuel). The results of the Geoprobe investigation are presented in GR's report 25-948223.1-3, Limited Subsurface Investigation Report, dated September 30, 2010. PROPOSED SCOPE OF WORK To further evaluate soil and groundwater conditions beneath the subject site, GR proposes to install one soil boring and one groundwater monitoring well at the locations shown on Figure 2. Field work will be conducted in accordance with GR Field Methods and Procedures which are included in Appendix A. To complete the proposed scope of work, GR proposes the following tasks: Task 1. Pre-Field Activities GR will update the site-specific safety plan and obtain the necessary well permits from the SJCEHD. Underground Service Alert (USA) will be notified a minimum of 48 hours prior to drilling. Task 2. Drilling Activities GR will install one soil boring and one groundwater monitoring well and at the locations shown on Figure 2. A California-licensed well driller will perform the drilling and install the well. A GR geologist will observe the drilling activities and prepare logs of the borings. Prior to drilling, the boreholes will be hand augered to 5 feet bgs to confirm that the locations are clear of underground utilities. The soil and well borings will be drilled with 8-inch-diameter hollow-stem augers. One soil boring will be advanced at the location shown on Figure 2. The boring will be drilled at a 60 degree angle from horizontal and will terminate at a depth of 27 feet bgs below the location of UST excavation soil sample TW-13. Soil samples will be collected at 5 foot vertical intervals beginning at 7 feet bgs. After soil sampling is completed, the boring will be sealed with neat cement grout to within 5 feet of surface grade and finished with native soil to surface grade. 3