Bradwell nuclear plant river walls removed by divers
Work is due to start this month to remove 730ft (224m) steel river barriers at a nuclear power station in Essex as part of decommissioning.
The offshore wing walls, at Bradwell power station, separated cooling water discharge and intake areas in the Blackwater River estuary.
Divers will cut the steel piles below the estuary bed level for removal by barge, in a 12-week operation.
Engineering specialists Costain and Red 7 Marine will carry out the work.
The river bed will be surveyed later to ensure no material has been left behind and excavated material has been placed back into the trenches.
Permission for the work was obtained from the Marine Management Organisation following a public consultation and environmental impact assessment earlier this year.
A central concrete structure will be removed at a later date after a consultation and award of a marine licence.
Gary Lott, Magnox project manager, said: "A notice to mariners has been distributed advising details of the project and the safety exclusion zone necessary for the protection of sea users and workers."
The power station stopped operating in 2002.