The Port of Tacoma began dredging contaminated sediments in Blair Waterway on September 15 in preparation to expand Pier 4.
The Port detected a marine biocide, called tributyltin, while completing a dredging inspection for the site evaluation to expand Pier 4 for larger ships.
The Port of Tacoma has agreed to complete the cleanup of the sediments, which the U.S. Environmental Protection Agency will oversee.
During the project, the Port of Tacoma will dredge an additional 500,000 cubic yards of clean sediment to make the base of the pier deeper as part of the pier expansion.
“In an effort to contain costs and remain competitive, shipping lines are increasing the size of the container ships, providing economies of scale. The planned upgrades to Pier 4 will allow Husky Terminal to handle two of the world’s largest ships simultaneously,” said Don Johnson, president of the Port of Tacoma Commission.
“Today, an estimated 1,500 jobs in Washington State are connected to the movement of cargo through Husky Terminal. These berth improvements will add capacity, creating the demand for additional family-wage jobs in the region.”
The contaminated sediments will be dewatered and trucked to a waste disposal facility. The Superfund phase of the work is expected to be completed by April of 2016 with an overall cost of $19.3 million.