News: RIO UPDATE 1-Rio Tinto's legacy uranium mine sees rehab cost blowout

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Sept 26 (Reuters) - Energy Resources of Australia (ERA) , Rio Tinto's (RIO) majority-owned uranium unit, on Tuesday forecast a material cost overrun and delays related to the rehabilitation of its Ranger mine in the Northern Territory.

The total rehabilitation costs related to the Ranger mine would "materially exceed" the previous forecast range of A$1.6 billion ($1.03 billion) to $2.2 billion, ERA said in a statement.

"The company is unable to confirm the estimated complete project schedule and total rehabilitation costs at this time, due to a number of uncertainties including the outcome of final 2022 Feasibility Study."

The final feasibility study for the site, which was due this month, will be postponed to October, ERA said, adding that the study will include a revised estimated schedule and cost for the Rangers project site through to September 2027.

The Ranger mine was closed in 2021, and ERA has been looking to raise funds for the sustainable rehabilitation of former mine assets.

Rio Tinto said in April it would buy A$319 million worth of shares in the company to help fund the cost of cleaning up the former uranium mine, which is surrounded by the Kakadu national park.

The uranium mine and the planned development of the nearby Jabiluka uranium concession were the target of some of the biggest environmental protests across Australia in 1998.

Shares of the Darwin, Northern Territory-headquartered company were down 2.6% by 0137 GMT, while the benchmark index (xjo) fell 0.3%.

($1 = 1.5571 Australian dollars)