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�..� � Mr Michael J. Infurna Jr. P.G., S.R.E.H.S. August 2, 2006 Page 5 3. Upon completion of well purging, a groundwater sample was collected from the spigot in laboratory-provided sample containers. The samples were immediately labeled, recorded on a chain of custody form, placed into an ice-filled cooler for transport to Calscience Environmental Laboratories Inc. in Garden Grove, California, a state-certified analytical laboratory. The groundwater samples were submitted under chain-of-custody protocol for analyses in accordance with the following analytical program: • TPHg, BTEX, and MTBE with sample preparation by EPA Method 5030B and DHS LUFT analytical method, • TPHd and TPHmo with sample preparation by EPA Method 3510C and DHS LUFT analytical method, and • Volatile organic compounds with sample preparation by EPA Method 5030B and analytical method EPA 8260B. RESULTS Soil Profile The soils encountered in all seven borings were similar. The top 6 to 10 inches consisted of aggregate base/gravel that was underlain by a mainly silt-rich horizon (silt, slit with clay, clayey silt, silt with sand, and silt with gravel) to a depth of approximately 3.3 to 3.75 feet bgs. The silt horizon was underlain by a hard pan at a depth ranging from approximately 3.3 to 3.75 feet bgs. The hard pan was encountered in all of the borings except the two shallow borings HA-6 and HA-7. No soil discoloration or hydrocarbon odors were apparent in the any of the borings except HA-5. Trace-level or no PID readings were measured during field screening of the sol samples from all borings, except HA-5 (Table 1). Some slight discoloration and hydrocarbon odors along with elevated PID readings were observed in the soils encountered in boring HA-5 (HA-5-S-1.5' at 68 ppm and HA-5-S-3.5' at 58 ppm) (Table 1). Soil Analytical Results Analytical results and PID readings are included in Table 1. TPHd was detected in 6 of the 13 (including the duplicate) soil samples at concentrations that range from 6 to 24,000 milligrams per kilogram (mg/kg). The two highest concentrations of TPHd were detected in both samples from boring HA-5 (HA-5-S-1.5' at 24,000 mg/kg and HA-5-S-3.5' at 17,000 mg/kg). TPHmo was detected in 3 of the 13 soil samples at concentrations that range from 67 to 15,000 mg/kg. The two highest concentrations of TPHmo were detected in both samples from boring HA-5 (HA-5-S-1.5' at 15,000 mg/kg and HA-5-S-3.5' at 13,000 mg/kg). TPHg range hydrocarbons were also detected in the same 2 of 13 soil samples at 1:\PG&E\2nd Pz 11veport\Final PGE French Camp 2nd Phase 11.doc