Vedanta Resources' unit Copper Mines of Tasmania (CMT) is planning to resume operations at Mount Lyell copper mine.
The mine was placed under care and maintenance following two incidents where three workers were killed and then 200 staff members were laid-off.
In December 2013, two people fell about 20m down a mine shaft, and another worker died in a separate incident involving an underground mud rush.
CMT has secured approval from its parent company to resume development work at the mine later this year, reported ABC.
During the final feasibility stage, the company intends to design the mine layout, as well as new operating and safety systems. It will also evaluate the economic prospects of the project.
Construction work for the new operation is expected to commence in October or November, and start mining in the same period next year; however, a Tasmanian union has warned that worker safety at Mount Lyell cannot be guaranteed until findings for the previous incidents are released.
ABC quoted Australian Manufacturing Workers Union (AMWU) spokesperson John Short as saying that the company should allow time for implementation of safety measures and should not resume operations until it had considered the WorkSafe's findings.
Short said: "It's a tragic event what happened there, over those six weeks, but we want to make sure that never happens again.
"And unless we know what happened, we can't foreshadow what's going to happen in the future."