Holding a paddle up means "halt," as Zarna Joshi with Rising Tide Seattle explains to kayakers on the beach at Seacrest Park in West Seattle before the group heads out to protest the Polar Pioneer, Shell's giant oil rig, which is moored at the Port of Seattle's Terminal 5 on Saturday May 16, 2015.(Alan Berner/The Seattle Times via AP) SEATTLE OUT; USA TODAY OUT; MAGS OUT; TELEVISION OUT; NO SALES; MANDATORY CREDIT TO BOTH THE SEATTLE TIMES AND THE PHOTOGRAPHER OUTS: SEATTLE OUT, USA TODAY OUT, MAGAZINES OUT, TELEVISION OUT, SALES OUT. MANDATORY CREDIT TO: Alan Berner / THE SEATTLE TIMES.

SEATTLE | Organizers say hundreds more people opposed to Arctic oil drilling are expected to protest Monday in Seattle, where a massive floating drill rig is parked on the waterfront.

The Polar Pioneer, which Shell hopes to use to drill off Alaska’s northwest coast this summer, arrived in Seattle on Thursday. Hundreds of protesters in kayaks and other vessels turned out on Saturday for a protest dubbed the “Paddle in Seattle,” and on Monday, organizer say they expect hundreds to flood the Port of Seattle’s Terminal 5 and Harbor Island.

They say they’re planning to flood Terminal 5 and engage in civil disobedience to stop any work on the rig.

The protesters say they are concerned about the risk of oil spill in the Arctic as well as the effects of burning fossil fuels on climate change. Officials in Alaska have touted the money the drilling could bring the state, as well as economic benefits to the Pacific Northwest, which uses much of Alaska’s oil.