Alcoa has confirmed it will be shutting down its Kwinana refinery after 60 years of operation.
Production at the alumina plant is set to cease by September this year at which time the 1200 strong work force will be scaled back to 250.
Staff numbers will then be reduced to just 50 in 2025.
Alcoa has stated the plant's age, operating costs and current market conditions as the reason for the closure.
However, the Kwinana facility will remain in care and maintenance for the foreseeable future and will continue to support Alcoa's Wagerup and Pinjarra operations via it's port facilities.
Production at both Pinjarra and Alcoa’s Wagerup refinery will not be affected by the decision.
The State Government has responded to the closure and said they are committed to supporting the impacted workers.
"My Government will step up to provide supports for local workers to retrain, reskill and look for new career opportunities in the local area," Premier Roger Cook said.
"We will continue to work with Alcoa to ensure its other operations in Western Australia - including its Pinjarra and Wagerup refineries - support local jobs into the future."
Mr Cook has pointed affected workers towards the Rockingham Jobs and Skill Centre, who are ready to work with Alcoa to match staff with employers in the Kwinana and surrounding areas.
In addition, a dedicated team at South Metropolitan TAFE is on standby to support displaced workers with tailored free career and training advice.
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