Yanzhou, whose subsidiary Yancoal Australia is seeking to merge with Gloucester Resources to create an $8 billion company listing on the Australian Securities Exchange, was reportedly studying data on Integra and might make final offers as early as this month, Bloomberg said.

Yanzhou already agreed in September to acquire two coal units of Wesfarmers in Western Australia for $296.8 million and was seeking to apply its specialisation in underground mining – especially longwall top coal caving – beyond China.

A spokesperson from Vale told ILN: “Consistent with company policy, Vale does not respond to market or media rumours.”

Last March, the New South Wales Department of Planning and Infrastructure cleared Vale’s proposed extension of its Integra mine complex despite earlier problems in the past with safety at the underground mine.

The director general allowed Vale to modify its project approvals to extend the north open cut out-of-pit dump to the east and south and increase the maximum height of the north open cut emplacements from 135m to 141m.

The department’s assessment found the proposed modification would lead to minor additional dust impacts for residences, with levels remaining below relevant criteria and resulting in a slight increase in noise levels which were unlikely to lead to perceivable differences.

The open cut coal mining operations are located south of Integra underground and comprise the north open cut and south open cut, including the recently approved western extension.

The open cut operations produce both semi-hard and semi-soft coking coal (70%) and thermal coal (30%) for export.

The underground operation produces high quality, semi-hard coking coal for export, with the current approved production level set at a maximum of 4.5 million tonnes per annum of run of mine coal.

Current approved maximum production levels are 1.5Mtpa of ROM coal from the north open cut and 4.5Mtpa of ROM coal from the south open cut.