The $9-billion mine northeast of Fort McMurray, Alta., is expected to eventually produce 110,000 barrels of crude a day, doubling Kearl's target capacity.
During peak construction, the Kearl expansion had a workforce of more than 5,000 people.
CIBC World Markets analyst Arthur Grayfer says the mine is starting up on budget and about a month earlier than expected.
The first phase of Kearl, also with a targeted 110,000-barrel-a-day production rate, started up more than two years ago.
During the first quarter of this year, the first phase of Kearl averaged output of 95,000 barrels a day.
The initial development cost $12.9 billion — $2 billion more than expected as the company ran into delays transporting huge South Korean-made modules to the mine site.
Kearl is a partnership between Imperial (TSX:IMO) and its U.S. parent, ExxonMobil Corp.
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