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1. 0 Introduction/Purpose As required by the Central Valley Regional Water Quality Control Board (RWQCB) , additional investigation of lead contaminated soils is proposed in conjunction with the Re- Manufacturing surface impoundment characterization and closure. The characterization and closure activities are being conducted under the jurisdiction of the RWQCB and the Toxic Pits Cleanup Act of 1984 (TPCA) . To further assess the lateral and vertical extent of soils affected by opera- tions at Re-Manufacturing, WaterWork proposes to drill, log and sample additional shallow soil borings. Soil samples will be collected in locations shown on Figure 1. The State Department of Health Services (DHS) is currently involved in an investigation at the adjacent business, which is also on property owned by Re-Manufacturing. In the interest of minimizing the investigative effort at the two sites, soil borings and samples may be used for inves- tigation of the adjacent site as well as Re-Maufacturing. Because of the rigid time schedule mandated by the RWQCB and substantial enforcement actions pending against Re- Manufacturing for failure to comply with the dictated time schedule, work must commence as soon as possible. 1. 1 Soil Sampling Methodology Up to sixteen six-inch diameter soil borings will be drilled using a hollow-stem auger drill rig under C57 license. Borings will be drilled to characterize the lead concentrations in shallow soils as well as identify soil stratigraphy (native vs. fill) . Borings will be drilled into native material (approximately 15 feet) to provide a cross-section of site lithology and valid statistical representation of lead concentration in native soils. Drill cuttings will be logged continuously for characteri- zation of soil type. Subsurface lithology will be charac- terized according to the Unified Soil Classification System by an experienced geologist or civil engineer and recorded on boring logs. Soils encountered will be monitored for organic vapors by placing a small amount of representative material in a sealed container, then measuring the concen- tration of volatiles collected in the head space of the container with a photoionization detector (PID) calibrated with isobutylene to the benzene standard . The values obtained at each measurement point will be recorded on the boring logs. Soil cuttings generated during the drilling process will also be screened for the presence of volatile organics using a PID. 1