Terra Nova slick 9 km long
The oil spill at the Terra Nova platform could be four times larger than first estimated.
Petro-Canada had estimated Sunday morning's spill involved about 40,000 litres of oil.
On Monday afternoon, the company said the spill could be as large as 160,000 litres.
The spill has created a slick about nine kilometres long and one kilometre wide.
Crews are hoping to start a cleanup operation Tuesday, when seas are expected to be more calm.
Two vessels are on the site, ready to deploy booms and skimmers, and a third vessel is on the way.
However, Petro-Canada says it may only be able to recover about a quarter of the oil.
A mechanical failure has been cited as the cause of the spill, the largest in the province's six-year history of oil production.
The oil was pumped directly into the ocean Sunday morning at the Terra Nova platform.
John Downton, director of communications with operator Petro-Canada, says production on the platform was suspended when the incident was reported.
"Our operating principle is that we don't discharge," Downton says.
"We take it very seriously. We are looking into it to trying to find out what happened to make sure it doesn't happen again."
The Canada-Newfoundland Offshore Petroleum Board has ordered a suspension of production operations at the Terra Nova platform, located 350 kilometres southeast of St. John's.
The CNOPB is investigating the incident.
Downton says a failure occurred in the machinery used to separate fluids brought up to the platform. The fluids contain water and crude.
Bill Montevecchi, a Memorial University scientist who studies seabirds, says even a small amount of crude oil is often fatal to wildlife.
"This crude oil is the kind of stuff where the bird gets that black heavy, kind of sludgy stuff on it," Montevecchi says.
"It's just lethal. Period."
Montevecchi says company and CNOPB officials should not be the only sources reporting spills.
He would like to see independent observers stationed on offshore platforms.
Terra Nova has been producing oil since 2002. It is the second-largest field offshore, behind Hibernia.