The restructure had been driven by continued challenging market conditions including increasing operating costs, declining coal prices and the impacts of a strong Australian dollar, the company said in a statement.
Abel is about 25km from the Port of Newcastle, with the portal coming off the high wall of the Donaldson open cut mine.
The underground lease area extends southwards from John Renshaw Drive towards George Booth Drive and is bounded on the eastern side by F3 Freeway and by Buttai Creek to the west.
Abel is a bord and pillar operation, which uses continuous miners for first workings and secondary extraction.
The two-stage process accommodates irregular shaped coal deposits, enables adjustment to extraction for better management of subsidence and maximises the efficiency of the operation.
The Toyota “LEAN” process was introduced to the mine during 2012 with the aim of reducing costs and improving productivity.
The mine uses existing surface infrastructure and the Bloomfield coal handling and preparation plant, rail loader and rail loop for coal processing and loading.