Power stations don’t just produce steam and air pollution. They also produce millions of tonnes of coal ash every year, which makes its way into coal ash dams. In Australia, coal ash is the 5th largest industrial waste stream.

Coal ash contains highly concentrated amounts of the same toxic contaminants and heavy metals that are found in coal, such as mercury, lead, arsenic and cadmium. The contaminants in coal ash can travel in surface water and groundwater and in the air as dust, so it’s important that it’s cleaned up properly.

In the Latrobe Valley, ash dams are built next to waterways and on top of groundwater. These dams are not built in a way that prevents environmental contamination and have been slowly leaching into surrounding groundwater.

A big part of the problem, is that Victoria’s Environment Protection Authority (EPA Victoria) are using guidelines for landfill sites, which are not fit-for-purpose and fail to adequately address management and rehabilitation of these sites. Additionally, there is a lack of public information available and transparency on management and monitoring.

In 2020, Engie, which owns the now closed Hazelwood mine, was issued a clean up notice after an ash dam that was not lined properly leached into groundwater.

The Environmental Protection Authority (EPA) fined the owner of the Yallourn mine and power station $7,584 after a rupture in an ash disposal pipeline in February 2015 led to 8.6 megalitres of ash liquid being pumped into the Morwell River.

In 2001, the then owners of Loy Yang A were issued with a clean up notice for groundwater contamination underneath its ash dam.

The report noted the clean-up notice did not require the company to clean up the source of the groundwater contamination. This groundwater contamination plume has not been cleaned up.

A US EPA risk assessment warns peak pollution from ash dams occurs 78 to 105 years after they first started operating.


Site visit to Hazelwood Ash Retention Area (HARA)  –  March 2022

The rehabilitation method that the Hazelwood operator Engie has proposed, is to create a full pit lake, filling the mine void using natural water sources to create a lake that flows through to the Latrobe River and Gippsland Lakes. This proposed plan is currently going through an environmental assessment called an Environmental Effects Statement (or EES) and it will investigate the likely environmental impacts of the project and how those impacts might be avoided or minimized.

The most concerning part of Engie’s plan is that they plan to submerge the coal ash dams which are inside the pit – in fact they have already started. This is because in the extreme weather events of June 2021, The Victorian Government declared an energy emergency to allow the Morwell River to be diverted away from its current path through the Yallourn coal mine so that its owners EnergyAustralia, could repair a protective wall that was at risk of collapsing. From that time, until early 2023, water from the Morwell river was diverted into the Hazelwood mine, covering the coal ash dams that are in the bottom of the pit.

Hazelwood Ash Retention Area (HARA) ash storage is located inside the pit.