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.
9/10/2007 0700-1900
OSCs Callaghan, (6)START, (5)ERRS personnel arrived on site.
South Fork Yamhill DD- ERRS crew piled soil below the excavation in the South Fork Yamhill DD as a temporary berm to prevent contaminated water discharge. ERRS staged cyclone fencing around contaminated stockpiles and placed orange snow fencing along the roadway. START collected one stockpile sample near South Fork Yamhill DD to confirm that imported fill materials were not contaminated.
Highway 18B H18- START collected 16 Geoprobe soil samples from 4 boreholes collected on the SE and SW shoulders of H18B.
Rock Creek Road Ditch RCR- ERRS personnel began to “pothole” with an excavator to determine if contamination was visibly present in the ditch parallel to Rock Creek Road. START collected 2 field screening samples and conducted field screening with a TVA-1000 FID/PID. Pothole #4 revealed obvious visual contamination at 18”-36” below bottom of the culvert outfall, and a 100ppm field screening result on PID.
Southeast Tank Farm SETF- No additional activity had occurred at the time this report was written.
9/11/2007
OSCs Callaghan, (6)START, (5)ERRS personnel arrived on site.
South Fork Yamhill DD- START collected a total of 12 samples during daily operations. START collected 4 confirmation samples from the sidewalls of the excavation in the South Fork Yamhill DD. START also collected 8 soil samples from the two soil stockpiles- 4 samples from the contaminated soil stockpile and 4 samples from the clean soil stockpile.
Highway 18B H18- No additional activity had occurred at the time this report was written.
Rock Creek Road Ditch RCR- No additional activity had occurred at the time this report was written.
Southeast Tank Farm SETF- START collected 12 Geoprobe soil samples from three boreholes inside the former Taylor Lumber facility.
- FOSC Callaghan decided to demobilize START and ERRS for the remainder of the week (9/12-9/15/2007). START will develop a comprehensive work plan for additional sampling and oversight of the culvert replacement.
-Disposal Optons:
EPA has used two critical pieces of "environmental" data to characterize the waste encountered at the Taylor Lumber's Yamhill DD management area: (Environmental data includes surficial grab samples in the Yamhill DD they may not be representative of deeper more contaminated soils.) 1) The data from the Remedial programs effort in 2006 that identifies dioxin findings and 2) the analytical data resulting from ER activity on August 22, 2007 (which covers other necessary data gaps including: metals, SVOC's and VOC's).
These shallow wastes are being considered "warm" wastes. EPA is working with disposal facilities and our state counterparts in Oregon and Idaho to seek a variance for "warm" dioxin contamination encountered at the Yamhill DD. The variance is based on actual health threats posed by Dioxin/Furans (D/F)as a group instead of a strict interpretation of individual D/F levels per RCRA. This approach has been successful used by EPA in the past. Most recently it was used at the Coville Pole and Post site under the direction of OSC Mike Boykin with assistance by EPA's RCRA Technical Expert Dave Bartus. More specifically the dioxin congeners that exceed the land disposal standards had acceptably low toxicity equivalency factors (TEFs), which are the weighting factors that are used to calculate the toxicity equivalency quotient (TEQ).
This same approach seems appropriate for the Taylor "warm" dioxin data from 2006. At Colville when the concentration of each D/F (dioxin / furan) congener was adjusted based on the TEF, OSC M.Boykin was able to demonstrate that the stockpiled soil samples did not exceed the land disposal standards, based on the adjusted results.
EPA is proposing that this may be a viable disposal option for the "warm" contamination initially discovered in the ditch at the Taylor Lumber site.
START contractors have calculated the maximum and average values for all D/F congeners, and have compared these to the land disposal restrictions and TEFs. EPA has discovered that if the D/F samples are averaged an acceptable TEQ is reached. This requires a variance for the D/F congeners that are individually exceeded.
EPA's RCRA Senior Policy Advisor's Dave Bartus and Tim Brincefield "are in agreement that the variance approach as outlined is sound, consistent with similar site responses, and seems an appropriate way to manage the contaminated soil remediation waste at the Taylor site given the facts/data provided. [They further advised that] US Ecology will need to request the variance from IDEQ, since Idaho is authorized for the RCRA program and it appears to us a letter along the lines of the variance request Waste Management made of Oregon last year would be appropriate, but US Ecology should consult with IDEQ as to the form the request should take and the info they need to make a decision."
There is the possibility that deeper subsurface contamination discovered on Thursday and Friday of last week are likely "highly" contaminated, represent the bulk of the 175 tons excavated so far and may need to be incinerated because it is doubtful that the variance will work for such highly contaminated soils. A compounding factor here is that dioxin sample analysis typically takes two to three weeks to compete. If time delays are unacceptable the only option for disposal may be incineration. Incineration costs are likely to be $1000 per ton. Material acceptable through a variance can be disposed for $175-250/ton.
-Potential HWY 18 contamination removal and excavation:
EPA met with ORDOT on Friday August 10th. ORDOT has agreed to a 50/50 cost share for up to $20K in the event that EPA decides to go after contamination under HWY18. The culvert running under Hwy 18 has failed, is rusted out and has allowed contamination to saturate underlying soils. This culvert will need to be replaced now or at some future time. If EPA determines it is appropriate to excavate soils under the highway ORDOT will be responsible for drafting all the specs, permitting the work (EPA is not required to submit for permits but to meet the substantive requirements only) and paving the topmost layers (8inches). EPA does not want to be held liable for the specifications but will conduct the construction per ORDOT oversight.
-Continue geoprobe to determine extent and degree of contamination.
On Monday one lane of Hwy 18 will be closed. EPA will geoprobe in the south lane of the Hwy. This will allow EPA to determine the east and west migration of contamination.
Late Monday or early Tuesday EPA will Geoprobe North of Hwy 18 in the Rock Creek DD MA and within the SETF MA (the SE portion of the Facility property) to determine North and Westward contaminant migration. This should complete EPA's extent and degree of contamination providing all the data needed to make further removal decisions.
-Submit selected soil samples to fixed laboratory for confirmation and waste disposal
-Traffic safety
-Identify proper disposal options. EPA's RCRA experts will advise on disposal
-Site access for geoprobe equipment
-Complications associated with Excavation need to be considered.
Excavation of further contaminated soils are complicated by roadways (Hwy 18 and Rock Creek Road), Facility buildings (Large 30 bbl above ground storage tank at SE corner of facility), and well established heavy vegetation. The easily reachable contamination on the South side of HWY 18 has already been excavated during EPA's investigation into extent and degree of contamination. Further excavation in the Yamhill drainage ditch will require the removal of well established trees and will begin to compromise the integrity of the river's shoreline. Chasing the soils too far to the east and west of the Yamhill drainage ditch management area will require extensive shoreline management and reconstruction. Shoreline reconstruction is estimated at $250-300K per an initial ERRS assessment.
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