Two mechanical failures led to the loss of about 1,000 barrels of oil from the Terra Nova offshore oil production vessel, Petro-Canada said on Friday.

The oil company, which operates the project on behalf of a consortium of companies, said it's trying to fix problems at the field about 350 kilometres southeast of Newfoundland.

Petro-Canada vice-president Gordon Carrick said there was no evidence of human error.




Two equipment failures caused a major oil spill last weekend, he said:

  • An oil and water separator did not work properly.
  • A chemical injection system that is supposed to aid the separation process malfunctioned.
Petro-Canada's own investigation showed oil may have been flowing straight into the Atlantic Ocean for up to four hours before it was detected early Sunday morning.

However, Carrick said he doubts oil flowed that long. A tanker was being loaded at the time and there was a constant watch, he said.

Crew members returning from a meal break first noticed the spill of about 165,000 litres of oil.

"[They] didn't notice anything and didn't smell anything. It was only after midnight, when they came back, that they smelled something and observed it on the ocean," Carrick said.

On Thursday, another 1,000 litres of oil spilled at a separate rig at the Terra Nova site. Much of that oil was recovered.

Production still suspended at oilfield

Production at the field – the second-largest oilfield off Newfoundland behind the Hibernia site – is suspended while the Canada-Newfoundland Offshore Petroleum Board continues its investigation of the spills.

Meanwhile, attempts to recover the oil spilled on Sunday have been suspended.

The slick is now so thin that it is more like a sheen on the water covering about 12 square kilometres , said Ed Martin, another Petro-Canada manager.

About five per cent of the oil has been recovered, Martin said.

"We had a lot of heavy weather at the outset," he said. "There was dispersion, there was breakup, there was evaporation ... and that continued until the weather broke and we got right on it."