The Port of Seattle plans to add underwater lands to its ongoing investigation into past environmental contamination at its Terminal 91 Complex under a proposed amendment to a cleanup agreement with the Washington Department of Ecology.
The investigation would coincide with a project slated for this winter to maintain the depth needed to continue mooring ships along one of the site’s half-mile-long piers.
A shoal – a buildup of sand and sediment – has formed along Pier 91. The port proposes to remove the shoal and at the same time test sediments for contamination.
Ecology seeks public comment on the proposal through January 5, 2016.
The port and Ecology signed an agreed order in 2012 under Washington’s cleanup law, the Model Toxics Control Act. The agreement sets up a process to study the 216-acre site to locate potentially contaminated areas and, if needed, propose cleanup alternatives and develop cleanup plans.
The terminal began more than a century ago as a cargo facility. It later was home to oil company bulk fuel facilities and a U.S. Navy supply depot before the port purchased the property in the 1970s.
The port completed an environmental cleanup of soil and groundwater contamination at a four-acre former tank farm site on the property last year.