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• - 2 - • February 10, 2012 Objective The objective of the proposed scope of work is to identify potential releases to shallow soil (i.e., less than 15 feet below ground surface [bgs]) in the areas of the four existing septic systems, as well as potential releases from chemical handling activities that may have impacted downgradient groundwater. Field screening procedures and Environmental Protection Agency (EPA) analytical methods will be used to assess the potential for subsurface impacts Scope of Work Prior to initiating field activities, ENVIRON will prepare a site-specific health and safety plan (HASP) in order to protect the health and safety of field personnel. ENVIRON will also obtain a drilling permit from the SJCEHD as required, which includes the preparation and provision of a work plan, HASP, site map, and other information. ENVIRON will mark the locations of proposed soil borings and notify Underground Service Alert at least 48 hours prior to the start of drilling and sampling activities. ENVIRON will retain a private underground utility locating subcontractor, who will use non-intrusive geophysical instruments to clear boring locations for underground utilities. ENVIRON will retain a C-57 licensed drilling subcontractor to conduct direct-push technology (DPT) drilling for shallow borings in proximity to the septic system locations, and hollow stem auger drilling equipment for installation of the temporary borings for grab groundwater sample collection. Lastly, ENVIRON will retain a California-certified analytical laboratory to conduct analytical testing of soil and groundwater samples collected from the site. Following underground utility clearance, ENVIRON will direct the drilling subcontractor to advance seven soil borings at the site. Soil cores (from the four shallow borings) will be logged for lithology by an ENVIRON geologist and soil headspace readings will be collected using a photoionization detector(PID) to screen for the presence of volatile organic compounds (VOCs). Four soil borings will be advanced to a depth of approximately 15 feet bgs in the area of each septic system leach field. Up to two soil samples will be collected from each boring. The number and depth of soil samples may be adjusted in the field based on observations and field soil screening results. It is not anticipated that groundwater will be encountered in these shallow borings. Soil samples will be sealed in glass jars or in sections of the acetate drilling liner, labeled, placed on ice in an insulated container, and transported to the analytical laboratory under chain-of-custody documentation. The soil samples will be requested to be analyzed for CAM 17 metals (EPA 6010B and 7400 series), polynuclear aromatic hydrocarbons (PAHs), and VOCs. Following sample collection, the borings will be backfilled in accordance with SJCEHD guidelines. The remaining three soil borings will be advanced to 70 feet bgs, and temporary wells installed (PVC casing, with a pre-wrapped filter pack screened interval positioned to intersect the groundwater table). Soil sampling or logging from these borings is not anticipated. Grab groundwater samples will be collected from each of the temporary wells, and the samples will be analyzed for CAM 17 Metals (dissolved; EPA 60108 and 7400 series), PAHs, and VOCs. The water samples for dissolved metals analysis will be filtered at the laboratory within 24 hours of sampling. Each temporary well will be removed after sampling and the borehole abandoned in accordance with SJCEHD guidelines. HAWAM126969A RLATracyBhm 1pBonng Pemt ApplicationNoik Plan.Docx