Residents of Gainford, Alta., are now allowed to return to their homes after a tanker train derailed in the area on the weekend.

A total of 126 residents were displaced early Saturday morning, when a CN train carrying liquefied petroleum gas and crude oil derailed.

Over the last two days, officials had been conducting controlled burns on some of the tanker cars in order to get rid of the flammable and dangerous cargo.

At a press conference on Tuesday, Parkland County Fire Chief Jim Phelan said all tankers have been burnt out, and CN spokesman Warren Chandler said crews have been deployed to the site to remove the remaining tank cars.

Chandler said CN has also begun a process of rebuilding the track, and hopes to have the railway operating by Tuesday night.

Highway 16, however, will remain closed for an undetermined length of time in order to facilitate work around the site, said Parkland County Mayor Rod Shaigec.

Shaigec said public safety is a “paramount concern” and the highway will reopen once the area is deemed safe.

Chandler apologized for the inconvenience, and said CN will remediate any damage that was done.

“As hard as we work to make CN safe and in spite of all the progress that we’ve made, accidents still happen from time to time,” Chandler said. “When they do, CN has the ability and the resources to respond promptly and effectively, as we believe we have done over the past four days.”

Environment Minister Diana McQueen said that no water bodies were affected, and that the air quality remained good.

Earlier Tuesday, county officials told The Canadian Press that water was being pumped into a tanker car, which still contained nearly 70,000 litres of propane.

The new approach came after the controlled burns failed to use up the gas that remains inside the derailed train's cars.

Residents were ordered out of their homes immediately after the derailment, which caused two explosions and a massive fire. They were told they would remain out of their homes for at least 24 hours, as a fire from three of the tankers carrying liquefied petroleum gas burned itself out.

The company said Monday the first controlled burn that took place Sunday night did not remove all the propane in the derailed tank cars and as a result, investigators had not been able to remove the freight cars. CN officials undertook a second controlled burn on Monday night.

The derailment is the third this month involving CN trains, raising new safety concerns for trains carrying flammable and explosive materials.

CN said no issues were found when the tracks were tested last week and train inspections were performed on Friday.

With files from The Canadian Press