Since 1966, Taylor Lumber and Treating operated a wood-treating plant at 22125 SW Rock Creek Road in Sheridan, Oregon.
Wood preserving chemicals, such as creosote and pentachlorophenol (PCP), were used during operations.
EPA has conducted at least three emergency actions at the site since 1994. During the first emergency response, an underground barrier wall was built to contain the most contaminated groundwater and soil, and an asphalt cap was installed over that area. A residential yard was excavated and backfilled, as well as ditches within and next to that yard and the lumber facility.
On Tuesday August 21, 2007 the US EPA's Emergency Response Unit responded to and confirmed reports that a release of suspected historic contamination had occurred during excavation activities in the southeast corner of the former Taylor Lumber facility. Excavation activities were being conducted under the direction the US EPA's remedial program and as part of the contractor's scope of work.
START work completed in September 2007 delineated the lateral extents of contamination along the four management areas (MAs). The results from September 2007 limited removal site evaluation revealed the following:
MA - South East Tank Farm (SETF) - Soil samples collected from boreholes located in the SETF area tested negative for the presence of contamination. No additional work in this MA is required.
MA - Rock Creek Road (RCR) - Subsurface soil contamination was detected in the ditch centerline and along the shoulder of the RCR MA from the driveway entrance to PWPO south to the intersection of Highway 18B. The contamination appears to be limited to several soil horizons below the RCR ditch and extends at least partially under Rock Creek Road. The Time Critical Removal Action (TCRA) will target the ditch centerline for removal.
MA - Highway 18B (H18B) - Subsurface soil contamination was detected in soil borings near both ends of the of the culvert on the north and south sides of H18B. Soil contamination is likely spread along the length of the culvert. The TCRA will target removing as much soil contamination as is practical. The culvert will also be replaced.
MA - Yamhill Drainage Ditch (YDD) - Subsurface contaminated soil delineation in the YDD MA was completed to the extent practical. Contaminated soils were removed from the YDD and stockpiled for future disposal. Several more areas of contaminated soil likely exists in this MA. However, due to the physical constraints of large trees, steep slopes, and highway 18B, further excavation may be limited in the YDD MA.
START completed a work plan for the removal of contaminated soil from the management areas. ERRS completed a work plan for contaminated soil removal, water removal, culvert replacement and temporary stockpiling.
In March 2008, START sampled two soil stockpiles on the Taylor facility and the stockpile of soil from the YDD MA area. The soil samples were sent to a fixed analytical lab and tested for F032, F034, and F035 treatment standards, and the analytical results were used to profile the contaminated soil for disposal. The analytical results and toxicity equivalency factors (TEFs) were calculated to determine the toxicity equivalency quotient (TEQ). The TEQ confirmed the contaminated soil could be disposed under a single variance at Waste Management's hazardous waste landfill near Arlington, Oregon (Arlington). Please see the earlier site-related PolReps for further discussion on the waste variance process.
EPA and ERRS completed the work inside the PWPO facility and the remaining stockpiled soils were transported to Arlington for disposal.
Three composite soil samples were collected by START on August 22 from the areas underlying the locations where soil had been stockpiled on the residential property. Trace amounts of SVOCs including PAHs were detected in all three samples. None of the results exceeded the clean-up standards that were used to guide the removal action along the east gully Yamhill Drainage Ditch. However, some of the PAHs do exceed the residential standards at 10E-6. To mitigate exposure, a 6-inch soil blanket was layered over the entire soil staging area, hydroseeded and covered with hay. Please note that the staging area referenced above was used previously as a pole staging area. Several treated utility poles are still present.
ERRS completed site restoration by spreading six (6) inches of imported fill across the START staging area and the areas where soil was stockpiled. Hydroseeding was completed along the east gully Yamhill drainaged ditch and banks. Hay was also used as a cover over the staging areas. ERRS demobilized from the site on August 29, 2008.
The removal action is complete.
A final removal action report will be prepared and filed.
Traffic safety was a key issue. ERRS subcontracted with a company to provide traffic control (i.e., flagmen and a certified traffic control supervisor) during all removal activities, including during the period of August 1 through 3, when Highway 18 was closed for the culvert replacement.
Soil stability during trenching activities was also a key issue. ERRS provided trench shoring boxes to protect workers and the surrounding road structure during excavation activities. Excavation depths were limited; deeper excavation was halted when START personnel evaluated that continued excavation could result in trench wall failure.
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