While a final decision is not expected to be made until the end of this year, in its half-year results, BlueScope confirmed that it would spend roughly $120 million on long lead-time items critical for delivery of ironmaking from 2026.

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The indicative cost of the project has now risen to $1 billion, up from the initiative indicative range of $700-800m.

BlueScope CEO Mark Vassella said that the decision secured the future of steel making at Port Kembla.

"The project ensures the supply of steel for Australia from 2026 while providing a bridge to transition to low or zero carbon technologies," Mr Vassella said.

The plans for the blast furnace, which is currently mothballed, would see the facility utilise traditional ironmaking techniques, rather than utilise green steel or hydrogen based technology.

The blast furnace would have additional abatement technology installed with an indicative lifespan of 20 years, enabling BlueScope to adopt low carbon steelmaking in line with its net zero by 2050 goal.

The Port Kembla steelworks has also achieved ResponsibleSteel certification, which recognises the sustainability of the operations across a number of indicators, including social, environmental and governance.

BlueScope is the fourth steelmaker in the world to receive the certification and the first steelmaking site accredited in the Asia Pacific.

"ResponsibleSteel is the global steel industry's first sustainability standards and certification program, which was designed by business, civil society, suppliers and consumers," Mr Vassella said.

For the business as a whole, the half year to December 2021 saw the best earnings in the company's 20 year history, with underlying earnings before interest and tax at $2.2bn and a net profit after tax of $1.64bn.

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