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a WESTERN GEOLOGIC; ESOURCES , INC , r I.Rendall/14 November 1969 3 During the period from 27 February 1989 to 2 March 1989,five borings,B-1 through 13-5,were drilled and completed as flinch diameter monitor welts MW-1 through MW-5,respectively. Welts MW- ® 1 and MW-5 were screened from 8 ft below grade to 32.5 ft and 24.5 ft, respectively. Wells MW-2 through MW4 were screened from between 16 R and 17 ft to between 20 ft and 24 ft. Thr screen was terminated at the top of the confining layer,below the fust water.bearing zone. Screens were brought up higher in wells MW-1 and MW-5 to capture any liquid hydrocarbons that might be present. Soil samples were collected from all five borings at approximately 5-ft intervals and rent under lk+� chain-of-custogty to Central Coast Analytical Services(CC 45)of San Luis Obispo,California for analysis by EPA Methoc`524.2. TPPH were detected 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};r+;und surface. The TPPH concentrations ranged from 4 ppm to 390 ppm. BTEX were not detected in soil samples collected from borings B-3 and B-4. BTF-X were detected in soil samples collected from boring.%B-1,13-2 and B-5,with benzene concentrations ranging from 0.2 ppm to 0.84 ppm. Groundwater samples were taken from the �- completed monitor 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 MW-J,MW-2 snd MW-3 at 30,000 ppb,9,000 ppb,and 4,000 ppb,respectively. .RTEX were detected in samples from wells MW` 1,MVV-2,and MW-5 with the highest concentrationof 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:ve 11 MW-5. Historic analytic results are included in Table 1. GROUNDWATER SAMPLING Wells MW-1 through MW-5 were sampled on 7 September 1989 by WGR eaviroamental technicians according to WGR's standard operating procedure for groundwater sampling included as Attachment A. All purged water%km collected and temporarily stored on-site in holding tanks pending results of laboratory analyses. The groundwater samples and laboratory supplied travel blanks,made Up of dcionized water at the laboratory,were sent under chain-of-custody to CCAS. The chain-of- custody forms are included as Attachment B. ANALYTIC RESULTS All groundwater samples,collected on 7 September 1989,were analyzed by CCAS for TPPH, BM and halocarbons by EPA Method 8260. The analytic results are presented in Table I. The laboratory reports are included as Attachment C. 104R3%'09