Wesfarmers (ASX:WES) and joint venture partner Sociedad Quimica y Minera de Chile approved a final investment decision to expand the Mt Holland lithium project in Western Australia, including the construction of a new integrated ore sorting facility, according to a Wednesday filing with the Australian bourse.

Wesfarmers said its share of capital expenditure for the project is estimated at between AU$645 million and AU$715 million in nominal terms.

The expansion will increase nameplate spodumene concentrate production to 760,000 tonnes per year from about 380,000 tonnes per year on a 100% basis, while reducing unit operating costs and accelerating cash flows, per the filing.

Meanwhile, the new ore sorting facility will recover stockpiled material that is unsuitable for processing, adding about 3 million tonnes of spodumene concentrate production over the life of the operation.

The construction of a second concentrator is expected to start in the second half of calendar 2027, with the first spodumene concentrate production volumes from the expansion due in the first half of calendar 2030, the company said.