The Government has put in place an interim management solution to manage the water levels in historic mine voids beneath Bendigo, while it investigates a long term and enduring solution.

In identifying and implementing any long-term solution the environmental, social and economic impacts to one of Victoria's leading regional cities needs to be carefully considered.

In 2015 an immediate response to prevent further recovery of groundwater levels was put in place in 2015, followed by an interim solution in 2017, these were implemented due to the uncertainty around the most appropriate way to manage the mine impacted groundwater in the long-term given the elevated levels of metals, including arsenic, mixing with the salty groundwater. There were also concerns around the inundation of the Central Deborah Gold Mine tourist attraction and the potential of odour (rotten egg gas), which had previously been experienced in the 1980s.

Without management, the mine impacted groundwater will ultimately discharge to the environment at several points across Bendigo as result of the mining activities and the natural water table level in this area.

The Department of Environment, Land, Water and Planning has been progressing investigations into understanding the issue and is working with local stakeholders and community representatives to develop long term management options for the mine impacted groundwater.

Total EC3/4 investment to date: $24.38 m

  • 2015-16 expenditure: $5.88 m
  • 2016-17 expenditure: $7.76 m
  • 2017-18 expenditure: $5.36 m
  • 2018-19 expenditure: $2.82 m
  • 2019-20 expenditure: $2.56 m

Bendigo Creek with courthouse in background

Progress

This project is continuing to meet its objectives for the immediate, interim and long-term groundwater management options, through the following actions:

Immediate solution

The immediate solution, which involved use of alternate underground storage and mining owned evaporation basins, concluded with the commencement of Interim Solution operations in August 2017.

Interim option (5 years)

The interim option to manage groundwater commenced operation in August 2017. The solution consists of treating the groundwater at a refurbished treatment plant, to remove arsenic and heavy metals, followed by reverse osmosis to remove salt. The treated water is discharged to the Bendigo Creek or re-used, the brine (salty wastes) are sent to an evaporation lagoon at Coliban Waters Epsom Water Reclamation Plant. Sludge wastes, containing the heavy metals, are sent to prescribed waste landfill. Coliban Water are operating the interim option on behalf of the State Government.

This solution manages the volume of water pumped from the Central Deborah Gold Mine tourist attraction and is currently funded to 30 June 2021. An extension to the interim solution is being considered to allow further time to develop the long term management solution.

Long-term solution

DELWP is continuing to work with an established Community Reference Group as well as State and Local Government Advisory Group, to identify, develop and facilitate implementation of a long-term solution for this issue, which will need to be simple to manage, cost-effective and balance the needs of different parts of the community.

Page last updated: 26/11/20