Stormy seas kept containment crews at bay Monday as estimates of an oil spill off the coast of Newfoundland increased dramatically.
As much as 170,000 litres of oil could have dumped into the ocean during a malfunction aboard the Terra Nova oil platform.
Original estimates said about 40,000 litres had spilled.
"It's a large spill," said Fred Way, acting chairman and CEO of the Canada-Newfoundland Offshore Petroleum Board, which monitors the industry in the province. "It's not an Exxon Valdez category, but it's a large spill."
The board has suspended operations at Terra Nova until further notice.
Bob O'Brien, of the environmental group Ocean Net, said the area is home to many nesting birds and there will be habitat destruction.
"You're dealing with nature and its forces," he said. "I think the infrastructure that we have in place to clean up spills is probably very adequate, but you can't fight nature and its forces."
Mr. O'Brien said he's comfortable that Petro-Canada has been diligent in preparing for such a spill.
"We just need a weather break right now," he said.
The spill was the largest yet for Canada's East Coast offshore industry. But it was tiny when compared with other major spills around the world. In 1989, the oil tanker Exxon Valdez leaked 42 million litres of oil when it ran aground on the coast of Alaska.
Rough seas Monday prevented crews from containing the slick, which had been driven 24 kilometres south of the platform by wind.
Aerial surveillance Monday showed the oil was beginning to break up and officials did not expect to have containment barriers in place until Tuesday at the earliest.
There is some containment equipment on board the platform but crews struggled with high winds and waves as high as six metres.
"That's beyond where you would expect containment barriers to be effective," said Dave Burley, manager of environment for the board.
Supply vessels were also tracking the spread of the spill.
The likelihood that a slick from Terra Nova, located on the Grand Banks 350 kilometres southeast of St. John's, would ever reach shore is very low, said Mr. Way.
Petro-Canada said this did not affect its response.
"Any spill is significant for us and we are treating this incident with the highest priority," said Ed Martin, incident commander for the company.
Petro-Canada said an outside response team had also been deployed to the area with additional containment and cleanup equipment.
"Sea conditions have been not ideal for putting spill equipment in the water so we've not been able to do a lot of that at this point," said John Downton, spokesman for Petro-Canada, operator and 34 per cent interest-holder in Terra Nova.
Petro-Canada said the spill occurred just after 1 a.m. local time Sunday morning.
Oil that would normally be separated from water was released into the ocean as a result of a mechanical problem.
"It was related to a problem with the separation process," Mr. Downton said.
Oil is brought to the surface mixed with water.
"In this instance, effectively what happened is the oil and the water weren't completely separated - there was still some oil in the water that was discharged," Mr. Downton said.
Petro-Canada estimates only about 20 to 25 per cent of the oil will be recovered. Most of the rest will dissipate into the ocean and eventually break down.