Soil sampling to determine cleanup plan for Ridgefield yards dealing with Pacific Wood Treating contaminants

According to the U.S. Environmental Protection Agency, dioxins occur naturally — think forest fires and volcanic eruptions — and are also human-made — burning from fireplaces, diesel engines and industrial processes. Most people are exposed to some degree, though long-term exposure to elevated levels can cause health problems.

The continued cleanup overlaps with Ridgefield’s plan to buff up its waterfront along Lake River, a stretch adjacent to downtown Ridgefield that connects with Vancouver Lake to the south and the Columbia River to the north. Port officials finalized its waterfront business plan earlier this fall, progressing a vision that has been a priority for decades.

Redeveloping the waterfront was contingent on the old industrial site’s cleanup and, after years of work and nearly $70 million of state investments, the land is considered habitable. Meanwhile, contaminants remain in the homeowners’ yards east of the waterfront property.

Ecology’s upcoming cleanup plan will be available for public comment once completed. Soil replacement in the 15 residential yards will be divided into two phases, though the timing of each is uncertain and is dependent on the plan’s finalization.

Once a property has its soil excavated and replaced, no further sampling or monitoring is required, Penner-Ash said.

“It is impossible to know exactly how long each property or right-of-way will take,” he said. “Once the upcoming sampling work is complete, we will have a better understanding of the work required at each location.”

Previous cleanup

For three decades, Pacific Wood Treating preserved logs with a mix of oil-based solutions and other chemicals, which would eventually be cut and fashioned into utility poles and railroad ties. The company was a successful economic machine — but to the detriment of the surrounding environment, according to previous reporting from The Columbian.

Chemicals leached into soil and groundwater for years on the property. When Pacific Wood Treating declared bankruptcy and halted its operations in 1993, it left the Port of Ridgefield in a tangle of contamination.

In 2009, Ecology found that contamination extended eastward past the facility’s boundary and into the neighborhood. They reported that dioxins likely settled in the neighborhood’s soil as airborne dust that was blown from Pacific Wood Treating’s facility or from trucks hauling treated wood nearby.

The EPA reports that nationwide dioxin levels in the environment have decreased in the past 30 years, but the compounds persist because they are slow to break down.

Cleanup kicked off in 1996 and continued through 2012. At the center of this undertaking was a steam injection system that removed nearly 25,000 gallons of liquid contamination, 1.5 million pounds of sludge and a million gallons of groundwater, according to Ecology. The old stormwater system was stripped from the property and replaced with new equipment.

From June 2014 to spring 2015, the port began cleaning soil in the railroad overpass, as well as sediment in the Ridgefield National Wildlife Refuge’s Carty Lake and Lake River.

Soil in 29 properties and surrounding rights-of-way in the neighborhood east of the site were replaced in 2016 and 2017.