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 SE 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.
Previous 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. ERRS will schedule the loading and delivery of contaminated soil under manifest to the Arlington landfill after the completion of contaminated soil removal.
July 28 through 31, 2008
OSC Heister, START (2) and ERRS (10) continued to work on site. During this period, ERRS focused on tasks for EPA's remedial program inside the PWPO (former Taylor Lumber) facility.
During this period, ERRS began to load stockpiled contaminated soil into trucks for off-site transportation and disposal. A total of 13 trucks were loaded during this period, and the waste was sent to the Waste Management Subtitle C landfill in Arlington, Oregon. START also collected surface water samples from the Yamhill drainage ditch and the South Yamhill River for analytical characterization.
While excavating a trench inside the containment zone in the PWPO facility, ERRS encountered soil that appeared to be contaminated with petroleum hydrocarbons. START monitored the trench excavation with a TVA-1000 flame ionization detector (FID) and photoionization detector (PID) and noted elevated readings. Therefore, the OSC directed ERRS to excavate the contaminated material from the trench and stockpile the contaminated soil for disposal along with the removal action soil stockpiles being sent off-site for hazardous waste disposal as part of the removal action. Contaminated soil from a second trench inside the PWPO facility was also excavated and stockpiled for disposal. The soil from each trench was stockpiled, and START collected a composite sample from each stockpile for analytical characterization.
August 1 through 3, 2008
OSC Heister, ERRS (10), and START (4) performed the culvert replacement and contaminated soil removal underneath Highway 18. The highway was closed to traffic at 5 PM on Friday, August 1st so that ERRS could remove the failed culvert underneath Highway 18B. ERRS began by cutting the road surface and then removing the pieces of asphalt. ERRS then excavated down to a depth of approximately nine feet to remove the failed culvert and any contaminated material encountered. The material excavated from the trench was stockpiled for later off-site transportation and disposal at Waste Management Arlington.
While excavating the trench, ERRS was careful to work around existing utility lines, including a sewer line, a water line, and two natural gas lines. To install the new culvert, the sewer line was temporarily cut and replaced, but the other utility lines were not disturbed. ERRS also used shoring boxes inside the trench to prevent trench collapse and to provide for worker safety.
During excavation, START collected a total of four samples from the trench bottom for analytical characterization. ERRS then lined the trench with the organoclay matt and placed a small amount of backfill. A new 36-inch diameter high-density polyethylene (HDPE) culvert with exterior corrugations and a smooth interior was then installed at the bottom of the trench at a sufficient slope for proper water flow. The trench was then backfilled with the Oregon DOT-approved ¾-inch minus, and the material was periodically compacted as it was being backfilled. Following the completion of backfilling, ERRS installed a water line for use as a possible future water conveyance, and then secured steel plates on the road so that traffic could drive over the highway pending future asphalt repairs. The highway was re-opened at approximately 11:30 PM on Sunday, August 3rd, which was ahead of schedule.
August 4 through 6, 2008
OSC Heister, START (2), and ERRS (10) were on site. START and ERRS excavated three test pits in the west side of the Yamhill drainage ditch to further delineate the extent of contamination. START collected soil samples from the test pits, which were submitted for analytical testing. START and ERRS then reshaped and stabilized the drainage ditch by placing rocks, rip rap, and logs to divert water flow and to prevent bank erosion during times of high water flow.
START demobilized from the site on August 6th. EPA and ERRS will stay on site to complete the work inside the PWPO facility and to load the remaining stockpiled soils for off-site transportation and disposal.
Following the completion of waste transportation and disposal and site restoration, the removal action will be completed.
-- Contaminated soil in stockpiles will continue to be loaded into trucks for off-site transportation and disposal at the Waste Management Subtitle C landfill in Arlington, Oregon.
-- Once all contaminated soil is loaded and sent off site, START will collect a composite sample of the surface soil underneath the soil stockpile locations for analytical testing to confirm that no contaminated material remains.
-- ERRS will then restore the property used for the soil stockpile and equipment storage and demobilize from the site.
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.
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