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2.5 SCOPE OF WORK The scope of work covered under this Health and Safety Plan includes the following: At the 14 March 2000 meeting, it was decided that the DTSC will act as the lead agency for this investigation and the PHS-EHD will provide regulatory oversight of field activities to minimize regulatory expenses. AGE reports will be submitted to both agencies. An authoritative sampling strategy will be followed to assess areas of known or suspected activities for contaminants most likely to impact the subsurface media. To meet the objectives of the DTSC, the following scope of work was derived from the 14 March 2000 meeting. Miscellaneous Storage and Tank Storage Area Advancement of two soil borings to 25 feet bsg in the vicinity of the previously excavated and backfilled soil in the driveway to obtain soil samples for confirmation analysis for lead, nickel, cobalt, copper, chromium, and cyanides(the target metals);this is an area that has had a known release of waste water that required excavation. The two borings are required to collect soil samples directly beneath the former floor of the excavation and at greater depth for analysis to confirm removal of potentially impacted soil.The first encountered native soil sample from each boring will initially be analyzed for pH and target metals. • Advancement of one soil boring to 20 feet bsg in the vicinity of the sump hole in the former tank storage area to collect soil samples for analysis as noted above. The sump hole was located under a valve in the tank. The unlined sump hole provides a potential vertical migration path for contaminants to enter the subsurface from any releases from the tank or tanks formerly located in the area. A continuous core will be collected from the boring to aid establishment of the site stratigraphy. Selected samples will be analyzed for pH,cyanides and the target metals note above. Only one shallow sample will be initially analyzed. • Advancement of two additional soil borings randomly located to sample shallow soil for pH, the target metals and cyanides. Total depth of borings will be 15 feet, with a continuous core collected from one boring and samples collected at projected points of contact of contrasting soil compositions in the second boring. Municipal Well Area • Advancement of one soil boring to first water in the vicinity of the municipal well to obtain a continuous core from surface to total depth and to collect soil and ground water samples. The water sample will be analyzed for the target metals,volatile organic compounds(VOCs) and pH; the continuous soil core will be utilized to identify permeable subsurface pathways from the site to the well bore. Samples form each soil type encountered in on-site borings will be analyzed as background samples as the soil on the adjacent site is not likely to have been impacted by operations on the RV Circuits site. Analyses will be for the same analytes tested for in on-site samples. As noted above, the measured depth of static water level in the inactive municipal well on the adjacent property was 30 feet Also as noted in Section 2.2 above,the drilling log for the California Water Service well on the adjacent site shows yellow clay from near surface to 26 feet below surface grade (bsg); from 26 feet to 30 feet bsg the log shows 'boulders'. The 'boulders', if encountered, may make obtaining the proposed total depth and a grab ground water samples difficult. A shallow zone of'boulders', if horizontally widespread, could act as a preferred horizontal migration route for impacted fluids during periods of high ground water elevation. Sample water produced from the municipal water well and analyze for metals,VOCs. Page 11