CO0020059 - Laserfiche WebLink

Home Browse Search

C A M B R I A Mr. Bob Gondek March 11, 2004 discernible oil-impacted soils, then collected confmnation samples from the floor(PI through P4) and sidewalls (SWI through SW3) of the excavation. Photographs 8, 16, and 17 show the receiving pit before, during and after over-excavation. Soil samples were analyzed for TPH in the gasoline range (C4- C12) and TPH extended range (C13- Coo) by EPA Method 8015M, and for BTEX by EPA Method 8021. No hydrocarbons were detected in confirmation samples SWI, SW2, and P2 through P4. TPH(C,3- C40) were detected at 9.9 and 7.8 mg/kg in samples PI and SW3, respectively. These sample results indicate that there is no significant oil impact due to oil recovery via the receiving pit. Soil sample results are summarized in Table 1 and the analytical © laboratory reports are included as Attachment D. CONCLUSIONS AND RECOMMENDATIONS CPL'S environmental efforts, conducted as part of the emergency response, successfully recovered over 400 bbl of crude oil between the vacuum truck recovery and disposed oil- saturated soils. Since CPL estimates that 750 bbl were released, approximately 350 bbl of crude oil remains in the site subsurface. Based on the results of the environmental emergency response activities: • The lateral extent of impact to vadose zone soils is well defined since oil impacted surficial soils were visually identifiable.In addition, all oil-saturated surficial soils and all standing oil has been excavated and stockpiled or removed from the Site. • Test pit excavation in the locations where vertical infiltration of crude oil appeared most likely found crude oil to between 5 and 9 ft bgs with evidence that the oil was still mobile.Therefore,the vertical assessment of crude oil impact is not complete. • Over-excavation of the receiving pit successfully removed all crude oil impacted soils to non-detect concentrations, except for two locations where minor concentrations of TPH (C13 - C40) were detected at less than 10 mg/kg. No significant impact remains in this area, and no further action relating to the receiving pit is necessary. • Hydrocarbon concentrations in soil samples collected along the pipeline trench floor indicate that only soil immediately beneath the rupture point was significantly impacted. The additional soil samples collected beneath the exhumed pipeline (approximately 250 ft in length) contained only TPH(C13 - C40) at a maximum concentration of 54 mg/kg. This indicates that the release did not flow along the buried pipeline, and that there are no other pipeline leaks at the Site. Cambria understands that Mr. Russell Kagehiro's insurer, Allied Insurance, recently retained Kleinfelder, Inc., to prepare a workplan for limited soil assessment at the Site. The assessment workplan is the first step toward remediation of the Site.Following Kleinfelder's soil assessment, a remediation workplan will be prepared and implemented with San Joaquin County oversight. The remediation workplan will include a protocol for post-remediation confirmation sampling. Planned future sale and commercial development of the Site should be considered as part of any future risk evaluation or site cleanup activities. 6