The Port of Tacoma has filed a federal lawsuit seeking to recover millions of dollars in environmental cleanup costs from chemical manufacturer PQ LLC, alleging the company is responsible for decades of contamination at a former industrial site on the Tacoma Tideflats.

The case, filed in the U.S. District Court for the Western District of Washington, claims that PQ and its predecessor entities operated a sodium silicate production facility on port property for many years. According to the complaint, industrial activities at the site resulted in the release of heavy metals and other hazardous substances into surrounding soil and groundwater.

Port officials allege that leaking storage tanks, chemical discharges and runoff from manufacturing processes contributed to environmental damage that exceeded cleanup thresholds established under Washington’s Model Toxics Control Act.

The port acquired the property in 2008 as part of a harbor development initiative. After conducting an environmental review, officials say additional contamination was uncovered in 2009 during work aimed at eliminating an invasive snail species. Subsequent investigations allegedly revealed the presence of heavy metals, carcinogenic compounds and other pollutants at levels requiring remediation under state law.

Since 2012, the port has worked with the Washington State Department of Ecology to investigate and address the contamination. According to court filings, more than $8 million has already been spent on assessment and remediation efforts across two parcels within the port’s boundaries. Officials estimate that future cleanup expenses could add several million dollars more.

The complaint notes that in 2016, PQ’s predecessor entered into a cost-sharing agreement with the port to address remediation expenses. However, the port alleges that the agreement fell apart in April 2025 following a dispute between the parties.

In its lawsuit, the port seeks reimbursement for past and future cleanup costs, along with attorney fees and related expenses. A representative for the port said the action aims to recover nearly $10 million in public funds already used to address contamination tied to historical industrial operations at the site.

Under Washington’s environmental statutes, property owners or operators at the time hazardous substances were released can be held financially responsible for remediation. The port argues that PQ, as successor to the prior operators, bears liability for the alleged pollution.

PQ LLC had not publicly responded to the allegations as of the time of filing.

The Port of Tacoma, located in Pierce County, ranked among the busiest container ports in North America in 2025. The outcome of the case could determine financial responsibility for one of the region’s significant industrial cleanup projects.