Canadian regulators looking at the social and environmental impacts of a proposed natural gas pipeline down the Mackenzie Valley are again delaying hearings. That setback came earlier this week. It¹s on top of word from Imperial Oil Ltd., Calgary, the project's lead proponent, that the cost estimates have jumped to $14 billion from $6.5 billion. New estimates include $3 billion for the gas gathering system, $6.7 billion for the Mackenzie Valley Pipeline and $4.2 billion to develop the anchor fields.

Imperial also postponed the project's finish date by three years to 2014. The changes were released in a filing with National Energy Board and Joint Review Panel in mid-March.

"The Panel is unable to schedule its remaining four topics until it receives and assesses additional information from Imperial," says Joint Review Panel spokeswoman Annette Bourgeois-Bent. New information from Imperial, detailing costs and timeline changes, is expected in May. That could push the hearings' completion to the fall, a year later than originally scheduled.

In a conference call after the regulatory filing, Randy Broiles, an Imperial senior vice president said the producer remains committed to the project, but "is concerned about its competitiveness." Broiles said he expects to hear from Canadian officials about aid in the next couple of weeks. "We look forward to discussing the fiscal framework with the federal government," he said.

Imperial said engineering and excavation work on the project are on hold until regulatory questions are answered and fiscal talks completed.

The 750-mile pipeline would ship up to 1.9 billion cubic feet of gas daily to southern markets from the Beaufort Sea coast in the Northwest Territories.