5:04 PM: A $6.8 million Port of Seattle project to remove 2,000 creosote pilings from the north end of Terminal 5 is about to start. Port commissioner John Creighton mentioned it in his “State of the Port” speech to the West Seattle Chamber of Commerce last month, and port spokesperson Peter McGraw tells WSB it’s about to begin:
he Port of Seattle will remove more than 2,000 creosote treated piles and 5,000 sq. ft. of overwater coverage from Elliott Bay, off the north end of Terminal 5, beginning this week.
The port has worked with the EPA, U.S. Army Corps of Engineers, NOAA Fisheries, U.S. Fish and Wildlife Service, Washington State departments of Ecology and Natural Resources and the Muckleshoot and Duwamish Tribes to plan and execute removal of the piles/overwater cover. The work is being done in advance of a Superfund cleanup project being undertaken by the Lockheed Martin Company in the same area.
Removal of the piles is required as part of a lease termination agreement with the Department of Natural Resources.
Through 2016 the port has removed 11,420 creosote treated piles and is on track to remove 80 percent of all creosote treated piles from port-owned facilities by 2026.
The Terminal 5 pile removal project is expected to be completed by the end of March, 2018.
There’s more backstory in this document from a Port Commission meeting back in June, and we have followup questions out about exactly how the pilings will be removed and disposed of.
ADDED TUESDAY MORNING: Port spokesperson McGraw has answered those questions with information from the contractor’s Demolition Work Plan – read on for the details:
We asked how the pilings will be removed:
A 60’ x 250’ long deck barge, the “Western Provider,” will be used for containment, processing, and transport of all demo piling, pier wood, and demo debris. The Provider has a new impermeable concrete wear deck and continues perimeter fences for containment, and will have heavy equipment on board for wood processing and handling.
A second barge, The crane barge “Whitehorse”, will have a certified M80 Manitowoc crane which will suspend an APE 50 vibratory hammer w/ pile boot on it for pile removal. The crane barge will remove all wood piers and piling, and place them on the Provider for handling, transport, and disposal.
The crane barge crew will first “loosen up” approximately 25 ea. piling at a time with the vibro hammer, then lay down the hammer on deck and rig & remove piling using log chokers for hoisting to the deck of the Western Provider. All piling will be hoisted and laid down on the deck of the Provider, at which time excavators w/ thumbs &/or shears; a log handler; and a loader will cut and push wood to one end of the barge. Redside’s crane crew will follow the procedures outlined in the DNR’s Best Management Practices for removal of piling (ie, attempt to remove using vibro 1st, then line pull 2nd, and pile cutoff as a last measure if necessary).
Piers 25 and 26 have deck structures that need to be cut, rigged, and removed prior to piling extraction. For these piers, Redside’s pile buck / crane crew will cut the deck and/or piling as necessary to rig and hoist sections of the pier in as large of pieces as possible to avoid chips and debris entering the water to the greatest extent possible.
Some work will need to be performed from a certified man basket suspended from the crane due to fluctuating tide elevations and/or the dilapidated state of some of the piers will be unsafe for foot traffic. Pier sections will be loaded directly on the Western Provider by the crane and set on the deck where a 2nd crew will process the wood and piling.
Piers 23 and 24 have some timber caps that will need to be rigged and hoisted directly to the deck barge for disposal prior to piling extraction & removal. All dilapidated shipway piling and broken off piling may require divers for cutoff. Redside will be providing crane barge support to the divers as necessary, and for fresh-heading shipway piling that are already too soft to clamp into the vibratory hammer. Crux Diving will dive from their own support vessel at times, and sometimes from the barge Whitehorse depending upon the operation. Divers will also rig larger debris items for crane hoisting and removal if found and as necessary.
Our question: How will they be removed and taken away, and to where?
All marine piling, pier wood, and debris will be loaded onto the deck barge “Western Provider” in attendance prior to disposal. The material will be 100% contained in a disposal processing area on the barge where it will be cut and pushed to one end of the barge as necessary to create space and a safe working environment for the disposal processing crew.
The debris will be handled primarily by machines: excavators with thumbs, log handlers, and loaders for brailing material into piles. Some hand cutting by chainsaw and/or gas powered chop saws will be necessary, but minimized to machine work as much as possible. Creosote logs will be cut into +/- 6’ lengths as required for Subtitle D landfill disposal by Waste Management prior to unloading at WM’s Duwamish facility.
Once the barge is full, it will be towed by Western Towboat the Waste Management’s Duwamish unloading facility. Due to the large size of the Provider barge, it is anticipated that approximately only 2-3 barge unloads will be necessary during the project. Upon arrival of the barge at the Duwamish facility, Waste Management is required to unload all debris for disposal using their large loaders and equipment. WM will offload the barge into containers and send the containers to their Subtitle D landfill in Columbia Ridge.