The facility was known to use chromated copper arsenate (CCA) to treat fence rails and mine lumber. RCRA had notified the facility regarding the proper disposal of CCA tanks located on-site, but residual product remains on-site with the potential to affect groundwater and trespassers in the surrounding community.
Arsenic contamination has been determined as the main contaminant of concern at the site, and an Action Memorandum has been approved for the removal action at the site.
Site work continues. The concrete pad has been excavated, along with an additional concrete pad that was discovered beneath the top pad.
There are 2 pressure vessels on site, and seven tanks which housed CCA product. Pressure Vessel 1 (PV1) continues to be addressed to remove residual product. Due to the long duration between the facility shut down and the current actions, most of the CCA residual waste has been solidified. Metal sanding wheels have been utilized to loosen up the CCA product, and pressure washing is ongoing in an effort to collect the material for disposal. Pressure vessel 2 (PV2), in which the RP had stated was never used for wood treatment activities, has been investigated, and PV2 is almost 2/3 full of CCA product. Each pressure vessel is approximately 60 feet long.
START has collected XRF sampling to further refine the extent of contamination across the site, and preliminary data indicate that there is mass contamination across the site, which is more than anticipated. EPA has received datavalidation results from the first of three sampling events, and the areas identified as contaminated will be marked off for disposal.
Metal debris and rail line removal has been completed in the rear of the facility to allow access to contaminated soil removal activities. Also, a rail car located in the rear of the building used to house CCA product and miscellaneous debris has been cleaned of residual CCA product using a scraping, shoveling, and power washing process.
Crews will continue the tank and pressure vessel cleaning of residual CCA product.
Soil excavation is anticipated to begin following the holiday remobe back to the facility.
Soil excavation, tank cleaning, and proper disposal of soil, sediment, contaminated rail lines, concrete pad, and residual CCA product is anticipated.
Excavated areas will be backfilled and compacted with clean fill material, and the fill material will be sampled prior to delivery to the site.
A structural engineer visited the site this week to determine the structural integrity of the building where soil removal activities will occur. The building appears to be built on a separate pad and foundation, and the concrete pad that was built was built up to the existing foundation. The concrete pad was removed to allow access to contaminated soil in the subsurface. EPA will await the report from the engineer to determine how close the removal action activities can occur near and against the building.
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