Superfund site in St. Croix region one of first to get Infrastructure Bill funding

Federal dollars will clean up toxic pollution at former wood treatment site.




3 minute read

Aerial view of Penta Wood Products Superfund site. (EPA)

The Wisconsin Department of Natural Resources has received nearly $1.4 million from the Environmental Protection Agency to clean up a polluted site near Siren. The funding will support work at the former Penta Wood Products Site, where extensive environmental damage was done during 40 years of operation. It is located in the Clam River basin, draining to the Clam and ultimately the St. Croix River.

Penta Wood Products treated wood posts and telephone poles at the site from 1953 to 1992, dipping them in an open tank of pentachlorophenol, or PCP. The dangerous chemical, as well as arsenic and other harmful substances, contaminated the soil, surface waters, and groundwater throughout the 80-acre property.

“For more than 100 years, the upper Midwest was the nation’s industrial center. But when factories and mills closed they left behind a legacy of toxic sites that are challenging to clean up,” said EPA Regional Administrator Debra Shore.

The EPA says the Penta Wood Products pollution was caused by “poor operating practices.” One of the key points of contamination occurred at a gully on the site, where the company discharged wastewater from its treatment facilities for decades. Today, soil is contaminated as far down as 100 feet below the surface, and a sheen of oily chemicals “floats on the aquifer.”

Plagued by pollution, the company abandoned the site in 1992, agreeing to pay $37,000 to the clean-up effort. So far, the federal government has spent $28 million.

“Additional work is needed to restore the environment. Since the entities responsible for the contamination no longer exist, the state and federal governments have had to step in,” said Christine Haag, Director of the DNR Remediation and Redevelopment Program. “This funding will be critical to cleaning up contaminated wetlands on neighboring properties and bringing us closer to achieving our ultimate goal, clean up and closure of this Superfund site.”

Penta Wood Products was declared a Superfund site in 1996, one of 40,000 sites across the country and one of 1,300 considered high priority.

At the Penta Wood Products site, the EPA removed nearly 30 tanks full of liquid and sludge and disposed of 43,000 gallons of a PCP/oil mixture and sludge. It also excavated and safely disposed of soil and other waste, mixed arsenic-contaminated soil with concrete and covering it with soil to XXXX, and built and operated water treatment and bioventing systems.

The first phase of clean-up at the site concluded in 2000, and monitoring has shown it’s protecting the environment and public health. But testing in 2017 found more areas with high levels of PCP, including soil and sediment in wetlands, surface debris consisting of sawdust, treated wood, and drummed waste.

Additional clean-up is needed to prevent any future problems, but the EPA couldn’t pay for it. The site has been part of a backlog of 49 across the country where clean-ups are incomplete. The new funding comes from the Bipartisan Infrastructure Law passed last year, as part of a renewal of taxes on chemical manufacturers, with an expected $3.5 billion in revenue dedicated to Superfund.

“Wisconsin is grateful for this significant award of federal infrastructure funding,” said Gov. Tony Evers. “This funding will help the DNR clean up our state’s rural environment and protect the health of nearby residents.”

The $1.4 million for the project will be used by Wisconsin DNR employees and contractors to remove the contaminated soil and sediment from a wetland, and cover other contaminated debris with clean soil. The work will begin this summer and continue into next winter.

The only other Superfund site in the St. Croix’s watershed is the contamination caused by 3M’s industrial waste dumps in Lake Elmo and Oakdale.


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5 responses to “Superfund site in St. Croix region one of first to get Infrastructure Bill funding”

  1. Mark Hove Avatar
    Mark Hove

    That’s great news!

  2. Glen Nelson Avatar
    Glen Nelson

    We must do better. Including siting laws that recognize current expansion threats. Weak law puts the bulk of cleanup expense onto the back of the public. Wisconsin’s siting laws are intentionally antiquated. Most businesses try to do their best, but the bottom line often overrules best intentions.

  3. Michael J Gallagher Avatar
    Michael J Gallagher

    This exactly why sulfide mining should never be allowed on the doorstep of the BWCA. The people always end up paying for the pollution caused by companies who go bankrupt after they damage it the land.

  4. Nate Johnson Avatar
    Nate Johnson

    The posts and poles were not treated in an open tank as was stated. The treating was done in a tghly sealed long cylinder that treated the wood under pressure for a timed process and the chemical was pumped back out before the cylinder was opened.

  5. […] projects include initial clean-up for a Superfund site in St. Croix County, an expansion of the Apostle Islands National Lakeshore trail network, funding for Great Lakes […]


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Superfund site in St. Croix region one of first to get Infrastructure Bill funding