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r + . Groundwater Monitoring Well Installations Results Report Flag City New West#1003,6437 West Banner Street,Lodi,California Page 2 site The Chevron site installed monitoring wells approximately 30-feet south of the New West site which showed significantly higher concentrations of methyl tertiary butyl ether(MTBE) than the Chevron onsite wells July 15, 2005 --Apex submitted a workplan titled, Workplan for Preliminary Site Assessment, proposing the installation of eight-soil borings July 15, 2005 — The SJCEH issued a letter to New West requiring a workplan addendum to define the lateral and vertical extent of the petroleum plume coming from the site utilizing monitoring wells (Appendix A) July 22, 2005 — Apex submitted a workplan titled, Workplan for Preliminary Site Assessment (Monitoring Wells)Addendum, proposing four first zone wells and two second zone wells on and off site The SJCEH accepted the workplan in a letter dated July 27, 2005 (Appendix A) WELL INSTALLATIONS AND SAMPLING Monitoring Well Installations On August 1, 3, and 11, 2005, Apex personnel supervised drilling, sampling and the installation of six groundwater monitoring wells (MW-1, MW-2, MW-3A, MW-3B, MW-4A and MW-4B) (Figure 2) Wells MW-1 through MW-3A and MW-3B were drilled and constructed by Woodward Drilling of Rio Vista, California and wells MW-4A and MW-4B were drilled and constructed by Cascade Drilling, Inc of Rancho Cordova, California according to the Apex standard operating procedures (SOP) included as Appendix B All soil samples were collected at 5 foot intervals and at obvious lithologic changes Soil samples were screened in the field with the use of a photo ionization detector(PID) Soil was logged using visual and olfactory observations according to the unified soil classification system Groundwater was encountered at approximately 15-feet below ground surface (bgs) Wells MW- 1 through MW-3A and MW-4A were installed to a total depth of 25 feet bgs with 20 feet of screen, well MW-3B was installed to a total depth of 40 feet bgs with 5 feet of screen, and well MW-3B was installed to a total depth of 48 feet bgs with 5 feet of screen Boring logs detailing the construction of the wells and the lithology encountered during drilling are included as Appendix C Well construction details are summarized in Table 1 Soil Sampling All soil samples were submitted, under chain-of-custody(COC) documentation for chemical analysis to California Laboratory Services Inc (CLS), a state-certified analytical laboratory, of Rancho Cordova, California