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Y w� - � �.-rte-. w ItN G1: 0t, 0t, IC ]Z F. Stll: ItCIiS , J.Randall/15 SCPCCMher 1989 the former location of the pump islands. i During the period from 27 February 1989 to 2 March 1989,rive borings,B-1 through 13-5.were g drilled and completed as 4-inch diameter monitor wells MW-1 through MW-5,respectively, Wells MW- 1 and MW-5 were screened from 8 fl below grade to 328 ft and 24.5 ft, respectively. Wells hiW-2 through MW-4 were screened from between 16 ft and 17 ft to between 20 ft and 24 ft. The screen was terminated at the top of the confining layer,below the first water-bearing zone. Screens were brought up higher in wells MW-1 and MW-5 to capture any liquid hydrocarbons teat might be present. • y, Soil samples were collected from all live borings at approximately 5-ft intervals and sent under chain-of-custody to Central Coast Analytical Services (CCAS) of San Luis Obispo, California, for analysis by EPA Method 524.2. TPPH were dctected only in borings B-1,B-2 and B-5,on the southern half of the site, and primarily in the first 16 ft of soil below the ground surface. The TPPH ® concentrations ranged from 4 ppm to 390 ppm. BTEX were not dctected in soil samples collected from borings B-3 and B-4. BTEX were detected in soil samples collected from borings B-1,B-2 and B-5,with benzene concentrations ranging from 0.2 ppm to O.94 ppm. Groundwater samples were taken from the completed monitoring wells MW-1 through MW-5 on 22 March 1989 and sent under chain- of-custody to CCAS for analysis, TPPH,reported as gasoline,were detected in wells MXV-1,MW-2 and MW-3 at 30,000 ppb,9,000 ppb,and 4,000 ppb,respectively, BTEX were detected in samples from wells MW-1, MW-2,and MW-5 with the highest concentration of benzene detected in the sample from well MW-1 at 3,600 ppb. In addition,1,2-dichlorobenzene(1,2-DCB)was detected at 10 ppb and Freon-113 was detected at 20 ppb in the sample from well MW-5, historic analS,ic results are included in Table 1. The estimated direction of groundwater flow was based on depth-to-water measurements taken on y the 22 March 1989(Table 2). GROUNDWATER SAMPLING W--IIs MW-1 through MW-5 were sampled on 12June 1989 by WGR environmental technicians Beverley Ualdwin and Madeleine Stanger.according to WGR's standard operating procedure(SOP-4) included-as Appendix A. All purged water was collected and temporarily stored onsite in 55-gallons drums pending results of laboratory analyses- The groundwater samples and laboratory supplied travel blanks,made up of deionized water at the laboratory,were sent under chain-of-custody to Central Coast Analytical Services(CCAS) of San Luis Obispo,California. The chain-of-custody forms are included i as Appendix B, 3 10112SC7