CALGARY, May 24 (Reuters) - A number of crude producers restarted operations on Tuesday in Canada's energy heartland as a mass evacuation of the Fort McMurray oil town entered its fourth week, though cool weather and light winds were expected to help firefighters tamp down the blaze.
No oil facilities or communities were in the fire's path as of Tuesday morning, said wildfire information officer Laura Stewart. The fire's estimated size was unchanged from Monday, at just over 520,000 hectares (2,008 square miles).
"Firefighters are continuing to take advantage of the cooler temperatures and calm wind and making progress," said Stewart. No rain was forecast.
On Monday, authorities lifted evacuation orders for all work camps in the area, a significant step for companies eager to restart production. The fire has shut down about half of the oil sands' production capacity.
Athabasca Oil Corp resumed operations at its Hangingstone site following a shutdown on May 5, before which time production volumes reached in excess of 9,000 barrels per day, the company said in a statement on Tuesday. Athabasca said it expected to return to normal operating levels over the next several weeks with no anticipated long-term impacts.
Suncor Energy Inc said on Monday that it was preparing for a staged restart of its operations, with some workers in the area doing necessary "pre-work."
"Given our current assessment, we are confident we can safely return people to the region to begin the process of restarting operations," Steve Williams, Suncor president and chief executive officer, said in a statement. "We believe that getting our employees back to work is an important part of the process to get things back to normal in Fort McMurray."
The regional government published a pamphlet late on Monday for evacuees planning their return. Some of the area's more than 90,000 evacuated residents may be allowed in starting on June 1, depending on air quality and other factors.
The fire destroyed entire neighborhoods in Fort McMurray when it burned into the city on May 3 and 4, but most of the city remained standing.
The booklet recommended that returnees bring at least two week's worth of food, water, and prescription medication with them.
"You are returning to a community that was profoundly affected by a wildfire," it said. "Services that you are used to or rely on may be limited for some time." (Additional reporting by Allison Martell; Editing by Jonathan Oatis)