(Adds details from police in paragraphs 7-8)
By Eric M. Johnson
SEATTLE, June 8 (Reuters) - Police dismantled a tent onMonday used as a staging area for protests in Seattle over RoyalDutch Shell Plc's use of the city's port as a home basefor a drilling rig that could depart this week for the Arctic.
Over the last month, activists have staged demonstrationsagainst the oil company's Arctic drilling plans, including onMay 16 when hundreds of protesters in kayaks and small boatsfanned out on a Seattle bay.
Seattle police dismantled but did not seize the 16-foot(5-meter) by 32-foot (10-meter) logistics tent central toorganizing the launch of a planned rig-stopping flotilla, saidBackbone Campaign Executive Director Bill Moyer.
He said discussions with the U.S. Coast Guard suggest thePolar Pioneer rig could begin its voyage to Alaska this week,possibly on Wednesday, though neither Shell nor shipping companyFoss Maritime has commented publicly on the schedule.
Environmental groups say drilling in the Chukchi Sea offAlaska could lead to an ecological catastrophe.
"We would like Seattle to mobilize as many craft on thewater as possible to be a flotilla through which this rig is notallowed to attempt to pass through," Moyer said.
Seattle Police Department spokesman Drew Fowler said thetent was taken down in a West Seattle park that doubles as aboat launch and returned to its owner, though he was not surewhether Seattle or parks officers dismantled it.
"Folks had been camping in the tent, which is not allowed inany Seattle park," Fowler said. There were no arrests.
Activists say they want to get boats on the water as soon asthey learn the rig is leaving the terminal. A mandatory safetyzone keeping watercraft at least 100 yards away from the rigwill expand to 500 yards when it hits the broader Puget Sound onits way to Alaska.
Activists are asking people to sign up for protest shifts sothey can be called upon to quickly mobilize when the rigprepares for departure.
The Coast Guard will enforce the safety zone in the PugetSound, spokesman George Degener said, adding that it can be"almost impossible" for the rig to stop if a boat were tosuddenly enter its immediate path.
Shell did not immediately respond to a request for comment,nor did Foss Maritime. (Reporting by Eric M. Johnson; Editing by Eric Beech)