Projects at Valero Energy Corp.'s (VLO) refineries in Quebec, Canada and Port Arthur, Texas have been pushed back to 2011, the company said.

"We are still very active in those," Chief Operating Officer Rich Marcogliese told analysts during a conference call Tuesday.

A project to install a new hydrocracker and expand the asphalting unit at the Quebec refinery is seen as making the refinery more efficient, but will not come online until 2011, after several other projects at the plant have been completed.

A plan to expand coking capacity - the processing of the heaviest part of crude oil - at the Port Arthur refinery - has also been delayed. A plant-wide turnaround has been scheduled for the refinery in 2009, and will include replacement of six drums on the existing coker.

The delay at Port Arthur is partially due to the large amount of work already under way at the refinery. The project will come online approximately one year after the coking project at the company's St. Charles refinery in Norco, La.

Valero shares recently rose 3.4%, or $2.40, to $71.81.

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