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Kennedy/Jenks Consultants [formerly IC], 1996a). Past reports do not indicate whether the wells were properly abandoned in-place or removed and backfilled. In 1992, a Phase 11 Site Investigation of the OU-1 area (Phase II) was conducted to address applicable findings from the initial Level One Environmental Site Investigation for the Railyard (IC, 1992a). The Phase II entailed advancing six borings (MW-1, MW-2 and B1 through 64) and completing two (MW-1 and MW-2) as groundwater monitoring wells. MW-1 was located in the northern-central portion of OU-1, and MW-2 was located in the approximate location of the former refuse pit). Soil samples were collected from the borings and analyzed for metals; polynuclear aromatic hydrocarbons (PAHs); total petroleum hydrocarbons (TPH) as gasoline and diesel (TPHg and TPHd); benzene, toluene, ethylbenzene and xylenes (BTEX); and volatile organic compounds (VOCs). Selected samples, including those with total lead concentrations greater than 50 milligrams per kilogram (mg/kg), were also analyzed for California Code of Regulations (CCR) Title 22 metals. Groundwater samples were analyzed for TPHg and TPHd, BTEX and VOCs. Results are highlighted below, and summary tables from the previous report are reproduced in Appendices D and E, for soil and groundwater, respectively: • Lead was detected in soil samples at concentrations ranging from 19 to 2,100 mg/kg. The highest concentration was found in a sample from boring MW-1, located adjacent to the railroad tracks along Sixth Street, at a depth of 0.5 feet below ground surface (bgs). Other metals were also detected. • The highest soluble lead concentration among these samples, 110 milligrams per liter (mg/1), correlated with the highest total lead concentration, from boring MW-1. • PAHs (fluoranthene and pyrene) were detectable at trace concentrations (up to 0.3 mg/kg) in one soil sample, from boring MW-1. • TPH was not detected in any of the soil samples. • VOCs (toluene and xylenes) were detected at trace concentrations (up to 0.01 mg/kg) in samples from one boring, MW-2, which was adjacent to the former refuse pit in apparent fill material. No VOCs were detected in soil samples from underlying native soil. • None of the target analytes were detectable in the groundwater samples. • Oil was not detected in soil samples collected adjacent to the oil-filled sump previously identified in the Engeo Level One Environmental Site Investigation. The sump did not contain oil or evidence of oil residual at the time of this investigation; the sump appeared to be a utility access box. Based on these results, an additional 14 surface soil samples (SS-1 to SS-14)were collected in the vicinity of MWA and analyzed for total lead (IC, 1992b). The goal of this effort was to delineate the extent of lead at concentrations greater than a proposed action level of 500 mg/kg (but project files contain no record that approval of this goal was sought from the Regional Water Quality Control Board [Regional Board] or DTSC). Lead was detected at concentrations ranging from 120 to 1,600 mg/kg (Appendix D), and it was concluded that additional sampling would be required to characterize the extent of the lead. Remedial Investigation Work Plan Page 3 Former Tracy Railyard, Tracy, California 9:Vs-groupW6nWb\050565777.03_uprr%09-reportslwak plaMi Bnardeztdoc