Posted July 11, 2019
A crew out of Virginia wrapped up their work on the Jekyll Creek dredging process June 24, so the curious-looking dredge and associated equipment seen around the north end of Jekyll Island will be gone before too long.
At the Jekyll Island Authority board meeting June 18, JIA Conservation Director Ben Carswell said the team from Cottrell Contracting will be on-site for a little while as they demobilize and pack up. As The News reported in March, the plans called for some experimental methods for dealing with the pluff mud brought up from the bottom.
“The closest disposal options are about seven miles offshore, and that’s very costly,” Jonathan Broadie, project manager for the pilot project and acting chief of navigation for the Army Corps of Engineers, said in a Corps report June 12. “So not only are we finding a place to put the material, but we’re also finding ways to help protect the marsh.”
Also, the mud has a tendency to move around a bit and not stay put like some other sediments.
A whole mess of it was targeted for a spot roughly 800 feet south of the St. Simons Pier.
“The majority of it — there’s 200,000 cubic yards, total — a majority of that is being pumped to a location that’s very simply referred to as the ‘deep hole,’ between Jekyll Island and Brunswick,” Carswell said. “It’s over 60 feet deep, some of the fastest currents in the sound, there, and I anticipate that majority will be dispersed. The Army Corps is doing a tracer study to monitor where the sediments go, to see if this is feasible and advisable enough for dredge spoil management for the future.”
According to the Corps, the contractors ran a line running 40,000 feet to place the spoil material around three feet from the bottom of the hole.
About 5,000 cubic yards sprayed out over a nearby marsh area in thin layers in an experiment to see if the process will strengthen the marsh and provide a new method for coastal resiliency against effects of climate change like sea-level rise and carbon sequestration.