South32 Shares Tumble Almost 10% Amid Worsley Alumina Impairment

By Stuart Condie

SYDNEY--South32 shares are on course for their largest one-day fall since March 2020 after the Australian diversified miner warned that environmental conditions could impact the long-term viability of its Worsley Alumina project.

The stock was down 9.9% in early trade Monday after South32 announced US$818 million in impairments, US$554 million of which was against majority owned Worsley Alumina in response to project conditions recommended by Australian environmental regulators.

South32 reported its fourth-quarter production on Monday, but investors were likely focused on concerns over flagship Worsley asset, Citi analyst Paul McTaggart said in a note.

Lower-than-expected fiscal 2024 Worsley Alumina production was attributable to a temporary bauxite conveyor outage, which also contributed to a 6% cut to the project's fiscal 2025 production guidance.

The stock was recently at 3.08 Australian dollars (US$2.06) and on track for its third-largest decline since it was spun out of mining giant BHP Group in 2015. Its two worst days were both in March 2020, when the Covid-19 pandemic was roiling global markets.

Write to Stuart Condie at stuart.condie@wsj.com

(END) Dow Jones Newswires

July 21, 2024 20:49 ET (00:49 GMT)

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