Suncor Energy says it has taken a step toward transforming one of its ugly duckling oilsands tailings ponds into an environmentally benign swan.

The oilsands giant is to announce next week that it is the first company in Alberta to successfully reclaim a tailings pond. The 2.2-square-kilometre area has been filled in and landscaped with 630,000 newly planted trees, bushes and shrubs.

“This has not been done before,” Suncor spokes­man Dany Laferriere said. “We have said that we could do it and this goes to show that reclaiming tailings ponds is possible and we are doing it.”

Suncor says it will continue developing the site over the next 10 to 15 years into a mixed forest with wetlands that can support wildlife, including waterfowl.

The company acknowledges that it has moved much of the toxic liquid tailings to some of the other eight ponds it operates.