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September 14, 1998 Page 5 As suggested by Mr, Infurna, conductor casing was placed in the vicinity of product line sampling locations P-5, P-7, and P-16 for possible future soil exploration Additionally, a conductor casing was placed in waste oil tank 1 pit Conductor casing locations are illustrated in Figure 2 See Attachment A for conductor casing specifications Groundwater or accumulation of runoff water was not encountered during any excavation, over-excavation, or removal activities Product Line and dispenser Sampling On January 8, 1998, Ms Mary Meays (SJCPHS-EHD) required additional investigation in the vicinity of the former and then current dispensers south of Boring B-5 Ms Meays specified that any piping observed must be fully located and removed, and any contamination observed must be investigated by trenching Furthermore, Ms Meays directed excavation and sampling in the vicinity of Boring B-3 due to "refusal" encountered during a previous soil investigation and the 56 ppm detection of TPH-g at 2 feet bgs On January 8 and 9, 1998, piping removal, over-excavation, and sampling activities were conducted in the vicinity of the product lines and former dispensers south of Boring B-5 (see Figure 4) Over-excavation was conducted in the vicinity of the northeast canopy support and west of Well MW-3 because several former product lines were discovered during then current product Iine removal and sampling Over-excavation activities of the former dispenser in the vicinity of Boring B-3 was performed due to the "refusal" encountered during a previous soil boring investigation All above activities were observed and approved by Mr Infurna An overexcavation-location map is presented as Figure 5 Soil samples from twenty sample locations (P-1 through P-20, Figure 3) were collected on J,.,ivary 8 and 9, 1998 from the product line excavations at depths ranging from 3 to 10 fc -, bgs The soil samples were analyzed for TPH-g, benzene, and MtBE Selected soil - - samples werq also analyzed for oxygenates (TBA, MtBE, DIPE, ETBE, and TAME) by EPA Method 8260 The maximum concentrations of TPH-g, benzene, and MtBE were reported from P-16 at 11, 0 64, and 5 7 milligrams per kilogram (mg/kg) respectively, at approximately 5 feet bgs With the exception of 15 mg/kg Tertiary amyl methyl ether in P-16 at 5 feet bgs, MtBE was the only oxygenate detected in product line samples Six dispenser samples (D-1 N, D-I S, D-I E, D-I W, D-1 C, D-2) were collected on January 8, 1998 from the former dispenser islands (Figure 4) Dispenser samples were analyzed for TPH-g, benzene, and MtBE TPH-g was reported only in D-2 at 15 mg/kg from approximately 4-112 feet bgs. Benzene and MtBE were not detected in any of the collected dispenser soil samples 16 Product line and dispenser soil analytical data is summarized in Table I Certified analytical reports and chain-of-custody documentation are presented as Attachment B 920-119 1 AIrKPULRPT DOC