SAVING CENTRAL DEBORAH GOLD MINE FROM FLOODING
In December 2011, Unity Mining advised Central Deborah Gold Mine and the City of Greater Bendigo that it would no longer work its “Swan Decline”, which runs under much of Bendigo. Unity’s draining of the Decline for their own work had maintained water levels at Central Deborah Gold Mine since 2001. When the Swan Decline was abandoned and the pumps pulled out, this interconnectivity between the Deborah line of reef and the Swan Decline that had benefitted us since 2001 became our enemy: with no practical way to isolate Central Deborah Gold Mine from the Swan Decline, and all the other reefs it is connected to, keeping Central Deborah Gold Mine dry in future will mean keeping much of Bendigo dry as well.
The Unity Mining workings underneath Bendigo have opened up huge areas underground, and also connected many of the formerly separate lines of reef. This has allowed much more water to flow freely, and turned a fragmented system of underground waterways into a single huge system. If nothing were done arsenic and salt-laden groundwater would fill every low-lying mine across the southern half of Bendigo and flow into local creeks and gullies. This isn’t table salt either, it’s heavy metal salts that are not welcome in public waterways. Hydrogen sulphide gas (smells like “rotten eggs”) will form in old workings and seep out causing much of the city to stink. This water would then flow downstream past agricultural landholders who have rights to use creek water and ultimately into Kow Swamp and on to the Murray River. This is a much larger matter than just saving the Central Deborah Gold Mine, which is why we have been working tirelessly to resolve the situation.
We have consulted with the Environmental Protection Authority, Coliban Water, Department of Primary Industries and Goulburn-Murray Water to ensure that while seeking to save Central Deborah Gold Mine, we are also putting in place a plan that takes into account an environmentally responsible solution that is in the best interests of the Bendigo community as a whole.
Currently, we have designed a system of two pumps that will be placed in the smokebox compartment of the Central Deborah Gold Mine shaft and set between Levels 10 and 11. Each pump will be rated to handle the maximum anticipated volume of water we could have to pump (we won’t know the actual pumping requirement until we are pumping). We will pump mostly at night, on off-peak power rates, and will be able to discharge water to the Londonderry Shaft for discharge to the Woodvale Evaporation Ponds. The Victorian Government has provided $300,000 in funding for new pumps to be installed at Central Deborah Gold Mine and this project is now in full swing as we race against time, with water expected to hit our tourist levels by September 2012.
MINE ORE BINS RESTORED
Restoration and stabilisation works were carried out on our historic 1945 original ore bins in May 2012.
The work involved installing new structural supports within the confines of the bin structure, whilst maintaining the historic appearance of the original structures. This work will ensure that these bins are preserved for the future and allows us to continue presenting the whole story of the history of gold mining in Bendigo and Victoria.
We are grateful to the City of Greater Bendigo and the Australian Government who provided funding for this project as part of the National Historic Sites Program which is managed by the Department of Sustainability, Environment, Water, Population and Communities. The work was carried out by Central Deborah Gold Mine staff, a local contractor and our consulting Engineer.