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• _ K L EIN'' FEE DER at Lincoln Center are perch loroethylene (PCE), trichloroethylene (TCE), and 1,2- dichloroethylene (1,2-DCE). According to the August report, groundwater flow direction beneath the site was generally east by northeast. Depth to water in the shallow A-Zone Wells during the June 2007 sampling event ranged from 15.12 feet in MW-118A to 39.38 feet in MW-113A. MW-118A is located on West Benjamin Holt Drive, approximately 4,900 feet southwest of the Lincoln Center boundary. MW-113A is located approximately 175 feet north of the intersection of Benjamin Holt Drive and Inglewood Avenue. Depth to groundwater for most of the wells located in the A-Zone is approximately 30-40 feet. The closest A zone monitoring wells to the subject site are approximately 650 to 800 feet west to north of the site. The nearest up to cross- gradient A-zone well to the subject site is MW-103A. Based upon review of the most recent groundwater analytical results for this well, PCE, TCE, cis-1 ,2-DCE, trans-1 ,2- DCE and Vinyl Chloride were not detected above laboratory detection limits during the July 2007 sampling event. The nearest A-zone piezometer with groundwater sampling data is PZ-002A-1 and PZ-002A-2, which are located about 600 north of the subject site. Review of analytical tables from the August 2007 report showed relatively low values in 1999 of PCE, TCE and cis-1 ,2-DCE at total concentrations ranging from 0.39 to 2.96 parts per billion (ppb). The nearest B zone well (MW-204B) is located approximately 700 north by northwest of the subject site. The analytical tables show none detect results over the last four sampling events between June 2005 to July 2007 for volatile organic compounds (VOCs) of concern. Prior to June of 2005, TCE, PCE and vinyl chloride have been detected in this well at total values for these compounds ranging from 0.33 to 9.61 ppb. The highest total concentration of these three compounds in this well from the most recent sampling event was 8.3 ppb in August of 2004. Task 1 — Permitting and Pre-Field Activities The San Joaquin County Public Health Services Department Environmental Health Division (EHD) requires completion of a well permit and payment of fees prior to advancing soil borings. Kleinfelder will prepare drilling permit applications for submittal to EHD along with the required fees. The permits must be approved prior to drilling and sampling activities. EHD usually requires up to approximately two weeks to issue the permits. The geoprobe subcontractor will contact Underground Service Alert 48 hours prior to conducting fieldwork to notify local utilities of our proposed subsurface work. Kleinfelder will additionally prepare a health and safety plan prior to proceeding with field activities. Task 2 — Advancement of Push Probes Based on the most recent groundwater monitoring report prepared by LFR, Kleinfelder assumes depth to groundwater is approximately 35 feet bgs. This depth to groundwater has been used in evaluating how many probe locations can be completed in a given day and associated costs. Please note various groundwater zones have 02001 PROP.ENVISTO7P271/DGD:Iv/ra Page 2 of 8 ©2D07 Kleinfelder October 31,2007