PERTH (miningweekly.com) – Uranium producer Energy Resources of Australia (ERA) has revealed the anticipated rehabilitation costs for its Ranger project area, in the Northern Territory, after last year warning of "material" cost and schedule overruns.

ERA on Wednesday announced that an independent review of the Ranger rehabilitation had estimated a cost of between A$1.6-billion and A$2.2-billion for the project, compared with the 2019 cost estimates of A$973-million.

Furthermore, the review found that completion of the Ranger project rehabilitation work would be between the fourth quarter of 2027 and the fourth quarter of 2028

Production at the Ranger mine ceased, in accordance with the Ranger Authority, in January of last year, concluding processing activity on the Ranger project area after 40 years of operation, during which time more than A$500-million of royalty payments have been made to governments and Indigenous interests.

ERA said on Wednesday that a key constraint for the company was the current Atomic Energy Act, which requires the rehabilitation to be completed by January 26. The miner has been engaging with the government and key stakeholders to amend the Act, and extend the expiry date of ERA’s tenure on the Ranger project area.

The board of ERA has now requested management review further options for the completion of the rehabilitation project, including a proposed revision to the methodology for capping Pit 3 to more traditional methods that could be subject to lower execution risk than ERA’s current approved mine closure plan, the company told shareholders.

The company is also reviewing all available funding options to ensure that the increased forecast cost of the rehabilitation of the Ranger project area will be adequately funded.

Parent company Rio Tinto has advised ERA that it is committed to working with ERA to ensure that the rehabilitation of the Ranger project area is successfully achieved.

Rio told shareholders that the company was reviewing the preliminary findings of the forecast.

At the end of December 2021, ERA had A$699-million of cash funding including total cash at bank, including A$535-million in cash which is currently held by the Commonwealth government as part of the Ranger Rehabilitation Trust Fund. The Commonwealth government is also holding A$125-million in bank guarantees.