sydneyrio tinto plc said it is seeking the resignation of the chairman of energy resources of australia ltd citing differences over the approach to rehabilitating the tappedout ranger uranium mine in northern australia rio tinto said era chairman peter mansell should step down as the small mining company had failed to put forward an acceptable funding solution to meet its obligations to rehabilitate the ranger site rio tinto owns around 86 of eras stock rio tinto has remained deeply concerned that the opposition to further uranium mining on the land of the mirarr people the traditional owners of the area has not been appropriately recognised in any funding proposals put forward by the independent board committee of era said rio tinto on monday the openpit ranger mine surrounded by the kakadu national park in the northern territory produced more than 132000 metric tons of uranium oxide across four decades before mining ceased in february era estimated the cost of rehabilitating the mine at between 16 billion australian dollars us896 million and a22 billion the rehabilitation cost has strained eras finances in july era said it had been engaging with major shareholders about a possible a300 million capital raising to continue its rehabilitation work through 2023 with new shares to be offered at a 1015 discount to its share price however rio tinto balked at the terms there remains a strong difference of opinion between rio tinto and the ibc on the terms of rehabilitation funding with the ibcs view that successful rehabilitation could underpin potential future growth opportunities despite the mirarr peoples longheld opposition to further uranium mining on their country said kellie parker rio tintos country head in australia rio tinto has become more sensitive to its relationships with traditional land owners following the destruction of two ancient rock shelters in australias mineralsrich pilbara region in 2020 that were culturally significant to a local indigenous group the juukan caves disaster led to the removal of jeansébastien jacques as chief executive and the ouster of other senior executives