Alcoa's environmental impact on Perth's water supply is under review. 

American mining giant, Alcoa, could face scrutiny from Western Australia's environmental authority for the first time, as concerns grow over potential effects on Perth's vital drinking water supplies.

The Western Australia Environmental Protection Authority (EPA) has confirmed the validity of the referral regarding Alcoa's mining operations, marking a historic opportunity for the agency to assess the company's activities. 

Alcoa's bauxite mine in Jarrahdale is located near the Serpentine drinking water catchment, a critical contributor, accounting for around 18 per cent of Perth's crucial drinking water resources during the previous fiscal year.

Notably, this marks the first instance, spanning the company's six-decade-long presence in the region, where the EPA will examine Alcoa's annual Mining Management Plan. 

Normally, this plan is reviewed discreetly by the state government behind closed doors.

The initial impetus for the EPA's intervention emerged from concerns expressed by the Western Australia Forest Alliance, an environmental advocacy group. 

The alliance raised a valid referral, prompting the EPA to embark on a week-long period of soliciting public input to decide on the scope of the assessment.

Alcoa's operations fall under the jurisdiction of the Alumina Refinery Agreement of 1961, enabling the company to bypass the state's environmental regulatory processes. Instead, Alcoa submits its yearly mining plan to a select group within the state government for approval.

This process, characterised by its lack of public consultation, has drawn criticism, especially given its potential implications for critical water supplies. 

The Water Corporation's request in August 2021 for Alcoa to halt operations near the Serpentine Dam underscored the water-related concerns. 

The dam sits a mere 100 metres away from Alcoa's mining activities, heightening fears of toxic runoff contaminating the water body.

Alcoa Australia's president, Matt Reed, has conveyed the company's willingness to transition into the EPA's assessment process. 

Reed emphasised the importance of collaboration with stakeholders and regulators to meet evolving requirements and expectations.

Campaign director Jess Beckerling of the WA Forest Alliance has expressed optimism that the review would lead to improved environmental outcomes, enabling public scrutiny of Alcoa's practices. 

Alcoa, in response, published a statement affirming its commitment to protecting drinking water and promoting responsible operations, highlighting its six-decade-long contributions to the region's economy.