The draft remediation plan for the ore basin recommends mechanical dredging and off-site disposal of the contaminated sediment.
The Remedial Action Options Analysis, prepared by a Bellingham, Washington-based consultant for the White Pass & Yukon Route, was reviewed at a borough assembly work session Sept. 24, with officials from WP&YR and Anchor QEA, along with representatives of Golder Associates, which prepared a risk assessment of the ore basin for WP&YR in 2018, and the state Department of Environmental Conservation.
“We have decent understanding of accessible areas in the ore basin,” said Derek Ormerod, of Anchor QEA.
The draft plan lists as goals for the project: cleaning up the significant concentrations of ore spilled into the water, reduce risks to people and wildlife, remediate sediment that could spread, and do it all without impairing use of the harbor.
Under the plan, sediment would be dredged, placed on a barge and transported to an approved landfill. The location would be determined by the contractor. The plan would remove up to 75 percent of the contamination, in part because no dredging would be done under the ship loader or pier.
The proposed work focuses on the seafloor around the loader, where past studies have shown the highest concentration of contaminants. A 2018 report for the railroad determined there is lead, zinc and mercury contamination in the harbor sediment, mostly concentrated around the ore terminal.
During a work session in June, Skagway residents were asked to give feedback on the plan, which was based on mechanical dredging. Some residents suggested using hydraulic dredging to reach the area underneath the pier, essentially using suction hoses to reach areas inaccessible to a dredging bucket.
Anchor QEA’s presentation Sept. 24 explained that hydraulic dredging would be unfeasible, due to dock pilings and other access issues. The borough owns the ore dock, which is leased to WP&YR. The ore loader on the dock is owned by the Alaska Industrial Development and Export Authority (AIDEA).
The report did not provide any cost estimates for the work, with WP&YR and AIDEA expected to share in the expenses.
“Attempting under-pier removal is likely to be favored by some members of the community,” the Anchor QEA report said. However, it likely would result in “ineffective removal results and/or contractor safety considerations,” the report said in a comparison table of different cleanup and remediation options.
The plan is undergoing final review by the state, and Anchor QEA has begun the application process for permitting as it continues engineering design.
The dredging could begin as early as next spring, but most likely will start next fall to avoid cruise ship season.
During the June meeting, Assemblymember Tim Cochran suggested the dredged sediment be mixed with cement and sold as blocks, as to not pollute someone else’s backyard when it is hauled to an out-of-state landfill.
Even when the dredging is complete, the site will likely be under controls from DEC, to prevent further contamination and any spread of remaining ore sediment. “A closure with institutional controls is the only option for this site,” said Kara Kusche, with the DEC contaminated sites office in Anchorage.
Kusche said the controls would not block improvements or building at the site, but would add an additional protection to ensure that any future development considers health risks to people.
The work does not require municipal approval. The dredging would occur in the basin area leased by WP&YR.
Mayor Andrew Cremata said it was good to see the plan moving forward, but expressed disappointment that the plan does not include cleaning up the sediment directly underneath the ship loader. “Hopefully, there’s some 11th hour arrangement that allows us access underneath the docks,” Cremata said.