vvEPA

Superfund Construction Project - Funding Pending

Penta Wood Products Superfund Site

Town of Daniels, Wisconsin

Site Description

The 120-acre Penta Wood Products (PWP) site, in the town of Daniels, Burnett County, Wisconsin, is a former wood treatment
facility, which operated on the 80-acre parcel from 1953 to 1992. Operations entailed treating wood posts and telephone poles
by dipping them in an open tank of pentachlorophenol (PCP). When operating, PWP utilized a main treatment building, an
oil/water separator building; a wastewater lagoon; a wood chip pile; and several other buildings, sawmills, garages and storage
sheds. PWP was found to have PCP- and arsenic-contaminated soil and groundwater due to dumping process wastes at various
locations on the property, discharging wastewater into a gully, spilling chemicals and using poor operating practices.

In 1986, the Wisconsin Department of Natural Resources (WDNR) investigated PWP's operations due to reports of multiple
chemical spills. A 1987 investigation found that the facility's groundwater was contaminated with PCP after WDNR asked the
site owner to assess the property's environmental conditions. EPA added the site to the National Priorities List in 1996.

Site Status and Cleanup Actions to Date

•	The original cleanup took place in two phases. From 1994 to 1996, EPA removed about 28 storage tanks containing
liquid and sludge and disposed of 43,000 gallons of a PCP/oil mixture and sludge off-site. EPA demolished the main
treatment building and contaminated soil was treated on site or disposed of off site.

•	In 2000, the cleanup was completed following further site investigations. EPA demolished all remaining buildings and
equipment, excavated and moved contaminated soil and woodchips to an on-site disposal area, stabilized arsenic-
contaminated soil by mixing it with concrete and then covering it with soil, constructed and operated a water treatment
system, built a concrete infiltration basin, cleared trees and brush, installed piping for the treatment system and
groundwater extraction wells, constructed and operated a bioventingsystem, and fenced the soil cover area.

• WDNR assumed financial responsibility and oversight for the cleanup in 2014. In 2015, as part of an EPA-approved
pilot study, WDNR shut down the groundwater extraction and bioventing systems. The four-year pilot study collected
data to determine if natural processes could address the residual groundwater contaminant plume beneath the PWP
property. The pilot study concluded in December 2019 and a report summarizing the pilot study data is due in 2020.

• In 2017, WDNR took additional PWP site soil samples and found elevated PCP levels. Results indicate that soil and
sediment in wetlands require additional measures to meet the site and surrounding properties' cleanup goals. WDNR
also observed surface debris consisting of sawdust-like material, treated wood and drummed waste in three locations.
Debris samples were collected for laboratory analysis of volatile organic compounds, semivolatile organic compounds
(SVOCs), metals, polycyclic aromatic hydrocarbons and PCP concentrations. Results showed arsenic, PCP and SVOCs
levels above State standards for direct contact and groundwater protection. WDNR subsequently sampled the soil
under the surface debris and confirmed that contaminant levels met the groundwater protection standards.

Project Pending Funding, as of the end of Fiscal Year 2019

This work entails WDNR and EPA excavating affected wetlands and addressing the surface debris areas to meet the PWP site's
cleanup goals.

Funding Through Fiscal Year 2019

EPA has provided approximately $28 million for cleanup activities at the site.

May 2020


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