In 2006, Humboldt Baykeeper, Ecological Rights Foundation, and Californians for Alternatives to Toxics successfully settled a lawsuit against Simpson Timber Company to require the cleanup of dioxin-contaminated tidal wetland channel at the former mill site adjacent to Humboldt Bay and the Del Norte Street Pier in Eureka. Dioxins are extremely toxic compounds that cause reproductive damage and cancer. Dioxins bioaccumulate in fish and shellfish, concentrating as they move up the food chain, harming humans and wildlife alike. 

At the former mill site and in an adjacent tidally-influenced channel, dioxins were found at levels tens of thousands of times higher than Environmental Protection Agency standards – some of the highest levels documented in the U.S. The test sites were near where Simpson commonly sprayed plywood in the 1960’s with the now-widely-banned wood preservative pentachlorophenol (a.k.a. “penta”).

In accordance with the 2008 settlement, Simpson Timber has excavated the contaminated sediment, restored the wetland channel, and installed groundwater-monitoring wells to ensure that residual subsurface contamination doesn’t leave the site. In addition, a Humboldt Bay Wetlands Restoration Fund was established at the Humboldt Area Foundation for restoration projects designed to offset environmental damage caused as a result of the contamination.

Humboldt Baykeeper continues to review Simpson’s groundwater and surface water monitoring being done pursuant to the settlement to determine the effectiveness of the remediation measures taken so far. Today water flows in and out of the ditch with the tides, and monitoring will continue to ensure the tides aren’t bringing toxic chemicals into the Bay next to the region’s only public fishing pier.