It's been almost a year since the Mackenzie Valley Environmental Review released its final report on Giant Mine's environmental assessment, but the federal minister of Aboriginal Affairs has yet to sign off on the $1 billion cleanup plan.

In the Northwest Territories’ legislative assembly yesterday, MLAs asked what's taking so long.

The territory's Environment Minister Michael Miltenberger is one of four ministers involved in the project.

“We're going to encourage him to get the response sooner rather than later,” Miltenberger said. “That's about all I can tell the minister at this point. The federal minister marches to his own drum.”

In December, AANDC Minister Bernard Valcourt accepted the majority of the cleanup plan, but asked for some changes.

The review board responded in February.

There's been no response from the federal government since then.

It's been about six years since the environmental assessment for the cleanup started.

The cost of the cleanup has been estimated at close to $1 billion.

However, further recommendations, including an independent monitoring body to oversee the cleanup, could push those costs even higher.