FIELD DOCUMENTS - Laserfiche WebLink

Home Browse Search

i.r k" KLEINFELDER 1 EXECUTPVE SUMMARY This is a report of Kleinfelder's soil assessment conducted at the former Aboveground Fuel Oil Storage Tank facility at San Joaquin County General Hospital in French Camp, California. The County of San Joaquin, Department of Capital Projects, retained Kleinfelder to conduct a subsurface soil investigation at the location of the former aboveground fuel oil storage tanks to assess the presence of petroleum hydrocarbons previously noticed in the surface soil adjacent to the tanks. Eight borings were drilled and sampled in the vicinity of the former fuel oil storage tanks on ., September 27 and 28, 1993. The borings were drilled to a maximum depth of 31.5 feet below ground surface. Soil samples were collected at approximate 5 foot intervals and screened in the field with an organic vapor flame-ionization detector (FID). Total Petroleum Hydrocarbons (TPH) as extractable were detected in only 1 Of 17 soil sample. A sample from Boring B-4 collected at a depth of 6 feet contained a TPH extractable concentration of 11,000 mg/kg; TPH gasoline and benzene, toluene, ethylbenzene, and xylenes (BTEX) were below laboratory reporting limits. Analysis of all other samples from the remaining seven borings and the deeper sample from Boring B-4 were below laboratory ,., reporting limits. Based on the analytical results and field evidence, the near surface soil (0 to 6 feet) in the vicinity of boring B-4 has been impacted with fuel oil. The depth of contamination should not extend beyond a depth of 11.5 feet, this illustrated by the clean soil sample in boring B-4 at 11.5 feet. L- Considering the results in the surrounding borings, the lateral extent of fuel oil should not exceed beyond a non-detectable area of approximately 25 by 25 feet. It is not known if r r contamination migrated beneath the concrete footing of the adjacent building; however, the depth of contamination should not exceed much beyond a depth of 11.5 feet. Based on the soil boring results, the total volume of fuel oil contaminated soil is calculated to range approximately 12 to 230 cubic yards. Kleinfelder recommends that the soil containing fuel oil be excavated and removed from the site and that clean import material be used to backfill the excavation; the excavated material should be disposed of at a proper disposal facility. 24-220152-E00/GR1-01(1993) Page 1 of 7 October 27, 1993 r.+ Copyright 1993 Kleinfelder, Inc.