Chevron Canada warned regulators five years ago it would be unable to clean up the vast majority of any big oil spill at a rig off the coast of Newfoundland that is poised to set a record for the deepest offshore oil well drilled in Canada.
Chevron began exploratory drilling this month in the Orphan Basin, about 430 kilometres northeast of St. John's. The project is known as Lona O-55.
At 2,600 metres below sea level, it is considerably deeper than the existing White Rose, Terra Nova and Hibernia rigs off the Newfoundland coast.
Those three rigs are the only active offshore projects in Canada.
The well at BP's Deepwater Horizon rig in the Gulf of Mexico is about 1,500 metres deep.
The unprecedented nature of the Lona O-55 project has raised concerns among environmentalists and industry observers about how Chevron would respond were the well to blow out, as it did in the Deepwater Horizon case.
An environmental assessment commissioned by Chevron and its partners in 2005 estimated there is only a 0.0086 per cent probability of an "extremely large" oil spill of more than 150,000 barrels. The probability of a "very large" spill, defined as greater than 10,000 barrels, was pegged at 0.026 per cent.
There is considerable dispute over the size of the Gulf Coast spill, but U.S. government officials believe it is leaking at a rate of 5,000 barrels a day, meaning it is approaching 150,000 barrels. The Chevron report notes that, before the Gulf Coast disaster, there were only five extremely large spills in the history of offshore drilling.
However, the report also concedes that, were a large spill to occur on the rough seas off Newfoundland, the company would be hard pressed to clean it up, even if response teams were outfitted with state-of-the-art equipment.
"Physical recovery of spilled oil off the coast of Newfoundland will be extremely difficult and inefficient for large blowout spills," the report states." First, the generally rough sea conditions mean that containment and recovery techniques are frequently not effective. Second, the wide slicks that result from subsea blowouts mean that only a portion of the slick can be intercepted."
The Chevron report estimates that only two to 12 per cent of an offshore spill could be retrieved under "typical wind and wave conditions."
The report used statistical models to determine the possibility that a large spill would hit the shores of Newfoundland. In all 14,600 trajectories examined, the oil never reached shore.
The report notes a spill could cause "relatively few" to a "very large" number of seabird deaths. But overall, it concludes a spill "will not result in any significant residual impacts" on animals.
A Chevron spokesman said the report's assessment of the company's ability to clean up a spill remains "realistic." But he noted that the same severe weather conditions that would make it difficulte to recover a spill off Newfoundland also would aid in naturally dispersing the oil.
"First and foremost, our focus for the Orphan project is on ensuring safe and incident-free operations and protection of the environment," said spokesman Leif Sollid, adding the company is confident it has the safeguards in place to drill the well in a manner that protects the environment.
The Canada-Newfoundland and Labrador Offshore Petroleum Board, which oversees drilling off Newfoundland, gave the project the green light in 2006 with an environmental assessment knows as a "screening report." Originally, the board was supposed to conduct a more involved assessment called a "comprehensive study," which involves public consultations. But in November 2005, the federal government relaxed the environmental-assessment rules for offshore projects, eliminating the need for a comprehensive study at the exploratory drilling stage.
Stephen Hazell, a lawyer with environmental-law organization Ecojustice, said big offshore projects such as the Lona O-55 should be subject to tougher reviews. "For important projects like offshore drilling, they should be subject to something more strict, especially given what we know now," he said.
A spokesman for the petroleum board, Sean Kelly, said it is "satisfied that the company identified the risk of a blowout in its safety plan and put plans in place to manage the risk, which includes focus on preventive measures."
Nevertheless, he said the board plans to announce "special oversight measures" for the project on Thursday. But he didn't elaborate. Last week, the Newfoundland government announced it had appointed a marine safety and environmental management expert to review the province's prevention and response plans.