Mad River Union
BLUE LAKE – A state agency is reinvigorating efforts to prevent dioxins at a former lumber mill site from reaching the Mad River and the drinking water supply of 88,000 county residents.
Announced last week by the Humboldt Baykeeper water quality advocacy group, a new round of groundwater and surface water sampling at the former Blue Lake Forest Products mill site between Arcata and Blue Lake will be done by SHN Consulting Engineers and Geologists.
The firm has been contracted by the state Department of Toxic Substances Control (DTSC), which has been testing and taking actions at the site for nearly 30 years.
Of concern is potentially migrating dioxins from pentachlorophenol (PCP), a wood preservative that was used at the mill site prior to Blue Lake Forest Products’ ownership.
The old mill site is about a mile upstream from Humboldt Bay Municipal Water District intake wells and the contamination has been a lingering issue. The district has opposed the area’s industrial zoning and subsequent cannabis manufacturing permits.
Jen Kalt, Humboldt Baykeeper’s executive director, said the new round of testing will include a tributary of Hall Creek, which flows into the Mad River.
Kalt described the DTSC’s new sampling, particularly of the tributary, as “really huge.” She said the surface and groundwater testing at the site will be used as a basis for further clean-up of the site.
“We expect there will be a public process later on down the road, once they develop the next clean-up plans,” she continued.
The site’s contamination occurred when the McNamara and Peepe Lumber Mill operated there. By the time the mill changed ownership in 1986 and became Blue Lake Forest Products, use of PCP had been banned.
But contamination remained and in the mid-1990s, the state ordered remedial actions, including capping at the mill’s main operations site.
As of 2003, the former mill’s lumber storage and main operation sites were deemed to be free of contaminants. But in late 2018, the DTSC declared that contaminants in the soil beneath the capped area had seeped into groundwater, whose levels had risen.
“The fact that the groundwater elevation has risen 15 feet since 2003 is really concerning, because that could be pushing the plume of dioxin contamination toward the Mad River,” said Kalt.
Results of the sampling are expected this spring. Timing of a clean-up remediation plan is uncertain but Kalt said Humboldt Baykeeper will press for action.
“It’s been a fairly long time that this site has been threatening the drinking water supply in the Mad River and there’s just no excuse for any additional delays,” she continued.
She added, “There are a lot of contaminated sites around the state but this one is the highest priority in Humboldt County at this point, because of the drinking water.”