Environmental organizations in Western Australia are challenging the operating license of Alcoa’s Wagerup refinery, located south of Perth, due to concerns regarding rising mercury emissions. Alcoa attributes this increase to various factors, including a rise in bauxite processing volume.
The Office of the Appeals Convenor has yet to review the filed appeal. Alcoa, a major player in the mining sector, has dismissed the worries surrounding heightened mercury emissions as conservation groups push for the revocation of its operating license. Mercury, which poses risks to both human health and the environment, is a natural by-product of bauxite mining and processing activities.
Alcoa operates in the only jarrah forest worldwide, producing alumina at its Wagerup facility, situated approximately 120 kilometers from Perth. Recent compliance reports indicated a significant increase in mercury emissions from the refinery in 2023, as highlighted in a license review conducted by the Department of Water and Environmental Regulation (DWER) earlier this year.
The emissions reached around 400 kilograms in 2025, nearly doubling the amounts noted in 2022. This surge has raised alarms at the Conservation Council of WA (CCWA), which formally appealed the approval of Alcoa’s operating license, citing potential threats to public health and the environment.
This appeal follows a challenging period for Alcoa, which has faced scrutiny for unauthorized land clearing. An Alcoa representative stated that the rise in mercury emissions is linked to changes in recovery processes and emphasized that there was no unexpected or uncontrolled release of mercury. They explained that the volume of bauxite processed at Wagerup has increased, which likely contributes to the elevated mercury levels.
DWER’s analysis of Alcoa’s license indicated that the primary cause of the rising emissions was an increase in the concentration of mercury within the bauxite being processed, along with a decline in the performance of condensers at the site. The review concluded that the increase in mercury emissions is manageable and does not pose an unacceptable risk to the environment or public health.
However, CCWA executive director Matt Roberts contends that Alcoa has failed to provide a valid justification for the increased emissions, arguing that natural variations in ore mercury levels are not a relevant excuse. He noted that as mercury emissions rise, so does its accumulation in the ecosystem, raising concerns about the potential environmental impact on threatened species.
Roberts highlighted that Alcoa’s license application did not include any research on mercury levels in the environment or its effects on vulnerable species such as the numbat, chuditch, western ringtail possum, rainbow bee-eater, black cockatoos, and Carter’s freshwater mussel. He stressed that mercury is a harmful neurotoxin that accumulates in the environment, posing long-term risks even if immediate health effects are not apparent.
In response to the ongoing situation, DWER has chosen not to comment while the appeal process is in progress. Professor John Mamo from Curtin University noted that mercury is a heavy metal with varying exposure risks, explaining that its presence in the soil can lead to leaching into water systems when disturbed by mining activities. He remarked that the risk associated with mercury exposure is contingent upon the dosage and duration of exposure.
The Conservation Council’s appeal remains under review and awaits a final decision from WA’s Appeals Convenor.
