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2.3. PREVIOUS INVESTIGATIONS On 25 September 1997, at the request of Mr. John Hinkel,AGE advanced eight soil borings on the site to assess soil for pH, chromium, copper and zinc.Four borings were advanced in the eastern portion of the plating bath area and four borings were advanced in the treatment/chemical storage area,as shown on Figure 2. Soil samples were collected from depths of 2 feet and 5 feet below surface grade (bsg) in each of the eight borings. The borings were reentered on 24 May 1999 to collect additional soil samples at approximately 6 feet bsg for analysis for lead. The borings were advanced by hand-augering through holes cut in the concrete-flooring. The samples were collected utilizing a harnmer-driven metric soil sampler loaded with pre-cleaned brass sleeves. The samples were properly preserved and shipped to a California Department of Health Services(DHS)-certified analytical laboratory under chain-of-custody.The results of the analysis are presented in Table 1. The pH of the soil samples ranged from 6.7 to 9.0 except for two samples from boring B7, which had pH values of 4.5 and 3.6 at 2 feet bsg and 5 feet bsg, respectively. Chromium concentrations ranged from 18 milligrams per kilogram(mg/kg) to 69 mg/kg. Copper concentrations ranged from 27 mg/kg to 60 mg/kg,except for the samples from boring B7 with 780-mg/kg copper at 2 feet bsg and 380 mg/kg at 5 feet bsg. Zinc concentrations ranged from 40 mg/kg to 485 mg/kg. Lead concentrations for soil samples collected at approximately 6 feet bsg ranged from 6.9 mg/kg to 9.6 mg/kg, except for the 6-foot sample from B7,which contained 110 mg/kg(samples from 2 feet bsg and 5 feet bsg were not analyzed for lead). The data is suggestive of an impact to the subsurface soil in the area of boring B7, which was advanced next to a small, circular, cement-filled sump in the eastern plating area. Samples from B7 had lowered pH and elevated concentrations of copper and lead. The pH levels of 6.7 and 6.8 in the 2-foot bsg samples from B6 and B8 may be within the normal range of soil PH for the area,but may also indicate a minor impact by low pH fluids; the soil samples from B6 and B8 did not contain obviously elevated concentrations of the analyte metals.The areas north and west of boring B7 are not assessed. The vertical extent of the impacted soil and the extent north and west of B7 are not known. The tank storage area east of the building has not been assessed. 2.4. SCOPING MEETING At the scoping meeting held at the site on 14 March 2000 between representatives of the DTSC, AGE, Mr. John Hinkel and the PHS-EHD, the site history, existing data and a scope of work for the site was discussed. The areas of potential concern and the proposed scope of work presented in this document resulted from these discussions and agreements.Areas of concern that require assessment for the DTSC include: A previously excavated and backfilled area in the driveway near the tank storage that had been impacted by a spill of liquids from a large poly tank; Soil in the vicinity of the small sump hole that accommodated valving for a former aboveground, poly tank in the asphalt-paved tank storage area; Soil and ground water characterization in the vicinity of the inactive municipal well on the adjacent property with identification of migratory pathways for water entering the well; Definition of impacted soil around boring B7, particularly north and east of the boring location and along the former drain line;and Assessment of soil in the vicinity of a concrete-filled floor drain in the material preparation area. Page 10