Thousands of Alcoa workers in Western Australia face an uncertain future as the global aluminium giant conducts a major review of its smelting and refining operations.

The US-based giant is reviewing its global smelting and refining capacity over the next 12 months as it looks to cut costs, divest assets, reduce plant sizes or shut them. Alcoa’s Kwinana refinery, south of Perth, is now in the spotlight as it is the company’s least profitable and oldest…