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K!_ FINFEI nFR On May 6, 2003, Kleinfelder's Staff Geologist arranged for the top of the septic tank to be uncovered and found the tank to be in sound condition. A single sludge sample was collected from inside the tank and submitted for laboratory analysis. The sludge sample was analyzed for total purgeable petroleum hydrocarbons as referenced to gasoline (TPH-g), total extractable petroleum hydrocarbons as referenced to diesel (TPH-d), and total recoverable petroleum hydrocarbons as referenced to oil and grease (TRPH). The laboratory results reported a concentration of TPH-g - 26 milligrams/kilogram (mg/kg), TPH-d - 900 mg/kg, and TRPH-8,500 mg/kg. Based on the results of the tank sludge sample, a workplan was requested by the EHD to conduct further soil and groundwater characterization (if needed) at the site. Kleinfelder prepared the workplan and submitted a copy to Mr. Mike Infuma from the EHD for review. Mr. Infuma expressed willingness to allow a new septic system to be re-permitted if it could be shown that leakage from the septic system has not impacted soil and/or groundwater beneath the site. FIELD ACTIVITIES Septic Tank Contents Characterization As previously summarized above, a sample was drawn on May 6, 2003 by Kleinfelder and analyzed. The septic sludge sample was analyzed for TPH-g, TPH-d, and TRPH. The laboratory results reported concentrations of TPH-g - 26 mg/kg, TPH-d - 900 mg/kg, and TRPH -8,500 mg/kg. A supplemental characterization of the tank contents was performed on September 3, 2003. The results showed small concentrations of Volatile Organic Compounds (VOC) 1,4- dichlorobenzene (0.0056 mg/kg), and metals; cadmium-1.5 mg/kg, total chromium- 4.0 mg/kg, hexavalent chromium 1.0 mg/kg, nickel- 5 mg/kg, lead- 12 mg/kg, and zinc- 400 mg/kg. Soil Sampling On August 13, 2003 Kleinfelder advanced a total of 5 hand auger borings (B-1 through B-5) to investigate the shallow subsurface soils near the septic tank, leach line, and seepage pit. A backhoe operated by Parrish and Sons Septic Service was used to excavate at predetermined intervals along the leach line. The intervals were chosen in accordance with the State of California Tri-Regional Board Staff Recommendations for Initial Evaluation and Investigation of Underground Tanks dated August 10, 1990. One of the soil samples (B-1) was collected from native soil approximately 6 inches from beneath the south end of the tank. One of the soil borings (B-2) was advanced on the northern end of the septic tank near the position of where the flange or transition from the tank to the leach line occurs. A total of two soil borings (B-3 and B- 4) were advanced at an angle along the excavated leach line, spaced at 20 foot intervals, to the area directly below the gravel pack of the leach line and into native soil. The final boring (B-5) was advanced next to the transition point of the leach line and seepage pit, and also below the gravel pack of the leach line and into native soil. See Plate 2 for the soil sampling locations. On August 29, 2003 confirmation sampling was performed by Kleinfelder with the EHD regulator (Mr. Mike Infama) present. One additional soil sample (B-6) was collected for laboratory analysis. 34202.E01 /ST03R1609 Page 2 of 7 Copyright 2003 Kleinfelder,Inc. October 31,2003