Submission guide: Have your say on Yallourn and Hazelwood’s Declared Mine Rehabilitation Plans

• The Latrobe River is already under immense pressure - The river system has been degraded by a century of coal mining, pollution and over extraction of the water it needs to function as a healthy living waterway. Taking more water — even from “high flow” periods — will cause further damage unless carefully regulated. Long-term climate trends point to less water availability, meaning we must prioritise resilience of the rivers and lakes which support us. 

• Using alternative sources of water - Alternative water sources – such as recycled water piped from the Eastern Treatment Plant and desalinated water - for rehabilitation have previously beenruled out as being financially unfeasable. But the analysis that led to this decision relied on river water being priced upon what coal mining companies have historically paid, which is almost nothing. These alternate water options were dismissed on cost grounds — but the comparison priced river water at an absurdly low $11.55 per megalitre. (A new independent report recommends raising  the price to $250-$300 per megalitre)This artifically low price has skewed the assessment at the cost of our rivers. 

• The Morwell River Diversion (MRD) is a levee which runs through the Yallourn Mine, running between two giant coal pits on Energy Australia Yallourn mine land. It has collapsed before and local community and experts expect that it WILL fail again.  Another failure would likely mean a significant loss of water and, due to contamination, risks to other water users and the health of the Latrobe River. 

• The MRD was designed so that fish and sediment nutrients could still flow from high in the Strzelecki’s through to the Latrobe River and downstream, feeding the life in the lower wetlands and beyond. However since the repair works to the MRD in 2021, the structure can no longer support high flows floods, which are essential for river resilience and flushing of the Latrobe River through to the Gippsland Lakes. High flows are now diverted into the mined-out Township field of the Yallourn mine, with Energy Australia planning for an engineered spillway to divert water via a coal pit before it enters the Latrobe River when they begin the full pit rehabilitation
   
  The Morwell River Diversion Collapse Issue 

  The Morwell River Diversion (MRD) was constructed to redirect the Morwell River around the Yallourn coal mine during active mining operations. It now runs between two giant coal pits on Energy Australia Yallourn mine land. Energy Australia Yallourn has acknowledged in their rehabilitation planning documents that this diversion infrastructure faces significant collapse risks as the mine pit is filled with water. The company has stated it cannot guarantee the long-term structural integrity of the MRD and plans to replace it with a substantially smaller levee system designed only to carry minimal environmental flows, with flood waters being redirected through spillways into adjacent fields.  

  The primary concern is the permanent loss of Morwell River flows to the broader Latrobe River system. Under the proposed rehabilitation plan, this ‘flood-skimming’ would divert a majority of the Morwell River's water to be captured within the mine pit rather than continuing its natural flow path to the Latrobe River and Gippsland Lakes. This represents a fundamental alteration to the catchment's hydrology, eliminating the variable seasonal flows and flood events that are essential for maintaining downstream ecosystem health, supporting aquatic biodiversity, and preserving the ecological values of the internationally significant Ramsar-listed wetlands in the Gippsland Lakes system. 

  The implications extend beyond immediate environmental impacts to include potential breaches of environmental legislation and existing water allocation frameworks. Climate change projections indicate that water yields across the Latrobe catchment may decrease by up to 30%, making the retention of natural river flows increasingly critical.  

  Current government risk assessments have not adequately considered these long-term hydrological changes, therefore approving mine rehabilitation plans without guaranteeing continued river connectivity could compromise existing water entitlements and environmental obligations under both state and Commonwealth legislation. 

• Coal ash contains concentrated levels of the toxic chemicals and heavy metals found in coal, these include lead, mercury and arsenic. The contaminants in coal ash can travel in surface water and groundwater and in the air as dust. We know that there are contamination issues at the HARA ash dump, as it isn’t lined properly and is already leaching contamination into the groundwater underneath it.  

• In 2023, our friends at Environmental Justice Australia commissioned an independent coal ash expert to examine Engie’s plans to flood the mine without removing the coal ash waste stored within the mine pit.  

• The report found that flooding the mine pit without the coal ash dump being removed would likely result in floating coal ash visible as a white film of ash on the rising pit lake. The ash would likely leach toxinswhich could  become mobile in the lake. The report suggested that that coal ash should be removed from the coal mine prior to any flooding.  

• The report also found that installing a ‘cap’ on the coal ash dump would be ineffective if the mine is filled with water. And that with or without a ‘cap’, chemical leaching when the Hazelwood mine pit becomes flooded with water is inevitable. 

• This is in contrast to Engie’s assessment of this risk in their Declared Mine Rehabilitation Plan. Their Risk Assessment and Management document (available to download from this page) lists the risk of water contamination from the Hazelwood Ash Retention Area (HARA) alongside the risk of contamination from the exposed coal, and considers this risk ‘eliminated’ but the explanation for why it’s no longer considered a risk relies on ‘capping’ which independent experts have advised is not sufficient. We’d like to see them remove the coal ash waste so that its toxins will not leach into the Lake water. If they don’t do that, the risk should not be considered ‘eliminated,’ and ongoing water monitoring and contingency planning should be established. 

Infrastructure Resilience 

Call for robust engineering solutions to ensure long-term structural integrity of river diversions and water management infrastructure and designs that prioritise durability over short-term cost savings. 

Environmental Flow Protection 

Demand critical environmental flows are returned to the Latrobe system before any water diversion or ‘flood-skimming’ for mine rehabilitation. Oppose excessive flood capture systems and call for enforceable limits and costs applied to any water losses to natural waterways. 

Transparent Governance 

Push for clear resolution of infrastructure ownership and responsibility between government and private operators before major water allocation decisions. Advocate for decisive management of water resources to address existing shortfalls. 

Regulatory Oversight 

Challenge inadequate water entitlement conditions that fail to account for infrastructure risks. Highlight obligations under environmental protection legislation and international agreements for management of RAMSAR listed Gippsland Lakes and wetland conservation. 

Precautionary Approach 

Advocate for protecting natural water flow patterns rather than accepting unproven engineering solutions that may compromise long-term environmental and community water security.