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r. 19 May 1997 AGE-NC Project No. 96-0266 Page 3 of 8 and P5 were analyzed for LUFT metals to provide "background" information. The concentrations of background levels represent the naturally occurring concentrations of any analytes, or the level which is observed prior to any release or impacted to the environment. The metals detected in near. the plating shop are similar to concentrations detected in the "background" samples. The two shallow soil samples collected from the plating area(I-1 and I-2) were also analyzed for silver and cyanide. Chromium, lead,nickel and zinc were detected in all samples analyzed. With the exception of sample I-1, concentrations of metals detected in near the plating shop are similar to concentrations detected in the "background" samples. The soluble threshold limit concentration (STLC)of lead is 5 mg/1(milligrams per liter or parts per million: ppm) and detected concentrations greater than ten times the STLC would warrant the analysis of soluble lead. Total lead was detected in sample I-1 at 110 ppm. However, after a subsequent analysis, the soluble lead was concentration detected was found to be 2.5 ppm I in'this sample. The two grab ground water samples collected in the area of Building I were found to contain LUFT metals;cadmium concentrations range from 0.008 to 0.012 ppm,lead from 0.54.to 1.3 ppm and zinc form 3.5 to 7.2 ppm. Chromium and zinc were detected at 1.5 ppm in both samples., , 2.3.2. CONCLUSIONS Hydrocarbon-impacted soil at the site is limited to the vicinity of the former UST within San Jose Street. Theimpacted soil was encountered in a somewhat narrow zone from depths of approximately 5 to 15 feet bsg. Hydrocarbon-impacted soil was not encountered southwest, north or east of the former UST area. The detection of MTBE in soil samples collected from probe boring P1 indicate the release of gasoline to be relatively recent, possibly within the past twenty years. Gasoline-impacted ground water is present around the former UST area in San Jose Street. The dissolved gasoline plume appears to extend to approximately 50 feet northeast and 50 feet southwest from the former UST location, and has an approximate width of 40 feet. Figure 3 depicts the estimated extent of the gasoline-impacted ground water. Diesel-impacted ground water appears to be limited to the southwest portion of the site; diesel fuel was not detected in grab water samples collected near the existing UST inside Building C. Since diesel fuel was not known to be used or stored on-site, an off-site source of the dissolved diesel in ground water is likely'. The laboratory analyses of the soil samples collected near the plating shop indicate that only low concentrations of metals are present in the shallow soil and ground water.