Suncor Energy’s Commerce City refinery is returning to full-scale operations after a shutdown that lasted more than two months.

The company is restarting Plants 1 and 3 in the coming days, according to an alert Friday from its community notification system. Suncor restarted the refinery’s Plant 2 on Feb. 9.

Suncor described the renewed operations as a “progressive restart” because it can take several days for equipment to heat up and run at full capacity.

“Over the coming weeks, we’ll be safely and steadily increasing production with an expected return to full operations by late March,” Suncor spokeswoman Loa Esquilin Garcia said in an email to The Denver Post.

Suncor announced in late December that it would cease operations to repair equipment that was damaged during a deep freeze and subsequent fires around Christmas. The shutdown drove up gas prices in Colorado, and it caused the refinery to commit multiple violations of its air and water permits that regulate how much pollution it can release.

Those permit violations remain under investigation by state and federal officials. The company also is investigating its shutdown, Garcia said.

When it operates at full capacity, Suncor’s Commerce City location refines about 100,000 barrels of oil per day and produces about 40% of the gasoline used in Colorado. The refinery also makes diesel, jet fuel and a primary ingredient used in asphalt.

Earlier this week, the U.S. Energy Information Administration blamed Colorado’s expensive gasoline prices on the refinery’s outage. Typically, gas prices drop during the winter because people drive less, but this year a gallon of gas in Colorado has risen 51% since the shutdown, the Energy Information Association reported.

The average price for a gallon of gas was $4 in Colorado on Friday, the fifth highest in the nation, AAA reported.

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