The company responsible for a uranium mine in the Northern Territory has announced it has lost both $54 million and its chief executive.

The Energy Resources of Australia (ERA) company released its half-yearly report today, which has said the significant losses include $21 million spent on an underground exploration decline.

ERA also said CEO Rob Atkinson will jump ship, moving to Rio Tinto after five years on deck with ERA. Mr Atkinson’s new ship is part of the same fleet however, with Rio Tinto holding a majority stake in ERA.

Earlier this year, Mr Atkinson said moving underground would extend the life of the Ranger operation by up to 10 years.

Open-cut mining at the Ranger site has wrapped up this year after digging for more than thirty. The open-air setup was moved to underground operation earlier this year, which Mr Atkinson believed would add ten years to its life.

The Ranger mine is located near Jabiru, inside the boundaries of Kakadu National Park, about 250 kilometres south-east of Darwin.

ERA says the reported decline in underground explorations is part of the company’s moves to establish the viability of other operations.