Meet our guests
Annaliese Mitchell, Kobie Johnson,Tania Hall, Amanda Stones, Mitchell Thompson
Host: As we manage the state's precious resources, we acknowledge the traditional custodians of this land and their connection to country.
A dark tunnel on the side of a hill with bats hanging from every surface. This is the image of an abandoned mine that we've come to expect from the movies. But the truth about abandoned mines is much more complex. From gold rushes to ghost towns, the legacy of an abandoned mine can have lasting impacts on the environment, on communities and on the social licence of the resources industry at large.
Hi, I'm Rachell Hansen and welcome to On the Ground, a podcast brought to you by the Department of Resources that unearths the rich stories of our people, showcasing how the work we do, drives sustainable prosperity for Queensland.
The department's role is to undertake works to make abandoned mines safe, secure, durable and productive. This work is prioritised based on the risk to community health and safety, the environment and property. And at the same time, repurpose and where we can, recommercialise abandoned mines to unearth previously undiscovered treasures. So how does this all happen? Today we're talking to the experts to find out more. Here's Annaliese Mitchell from Technical Services to break this down for us.
What types of mines are abandoned and why?
Annaliese: I guess they're sort of are those sites that are horizontal openings into what I can only imagine is something like out of an Indiana Jones movie. But I guess the other sites that everyone probably forgets about are the ones where I guess physically, you're looking at a site that sometimes they can be as small as someones had to scratch around with machinery. And maybe in the course of doing that, they've run out of money or found out that it's not viable.
So they leave the equipment lying around or, you know, they've left their big hole in the ground. Three small mines that might just be classed as a quarry. But they’re still a significant void or feature in the landscape that surrounds, and obviously there's different scales of that. We have our priority sites, which are the ones that pose a risk to health and safety and the environment.
Kobie: Hi I'm Kobie Johnson. I'm a Project Officer, as part of technical services. There's a data source called me MinOC, which is mineral occurrences that identifies about multiple thousands of abandoned mines. But they're not necessarily what most people would think of as an abandoned mine. So a lot of the time it's a shaft. It's a one metre little divot in the ground. What we're interested in are the more contemporary things that are, you know, tailings, dams, open pits, underground workings. Often you'll just you'll pull up to these sites and everything's it's like times just stood still. You know you'll see a cup of coffee sitting there, or someone's filled out the pre start board, and it's just sitting there, and obviously they've come up and done their pre start signed off, and then someone told them that that's it.
Host: An abandoned mine site is one where tenure no longer exists. But what does that actually mean to be an abandoned mine?
Kobie: I guess it has to have been an operating mine, obviously, first one and then to become abandoned by our definition, it needs to have a non-current resource authority i.e. mining lease or mine development, um, licence, and then it also needs to have an non-current environmental authority. So there's 2 parts to that. There's the mining mining lease, which allows you to mine the environmental authority, which binds you from an environmental point of view. If you have one and not the other.
So you have a mining lease and no environmental authority or that's been suspended, then you technically can't even mine. You need both of those things current at once.
Host: What are some of the alternative purposes or second lives of an abandoned mine?
Kobie: My background’s in geology. So a lot of the stuff I look at with these mines is the potential to recommercialise some of them i.e. see if we can get them back on the market and mining again.
Tania: There are quite a few sites that we have across Queensland, where there is opportunities for technology minerals that could be extracted from mine waste materials.
Host: This is Tania Hall, Director of Resources Remediation.
Tania: So, for example, we've got a site in Northwest Queensland, which was the Mary Kathleen Uranium mine. They extracted the uranium, and there is a significant amount of rare earths that were associated with the ore. And these rare earths were extracted as waste and deposited in the tailings storage facility, and they can be used for technology industries such as solar and renewable energies.
Host: What are tailings?
Annaliese: Tailings are what's left over after you process the ore and got everything that you want out of it. What's left over is usually still rich in other metals and minerals. That may not have been the target. When we talk about reprocessing tailings, we have these tailings, which looks like dirt and you go in, grab it and through some other process other than what was first used, you may get another mineral out of it or another metal. The Mount Morgan mine has been said that those tailings, they're still have quite a bit of gold in them. But it's just more of a metallurgical problem in terms of how you can actually get that gold. There's Kidston gold mines up north, and they've got open pits there.
But they've turned it into a solar farm, and they've got a pumped hydro project, and I think there probably will be a lot more renewable energy projects on, on these sites because they’re cleared already, they're quite open.
Host: Remediation in the mining context refers to the reparation of the damage caused to the environment during mining operations and to ensure there is no risk to safety around the site. Technical services is the name of the branch within Resources whose job it is to take on these remediation projects. Here's Amanda Stones to tell us more about what the team does. How do you determine which approach to take with each site that requires remediation?
Amanda: Every site is very different. They’re very individual, even 2 gold mine sites might have different challenges. So the first thing we do is do a risk assessment at the site. And, you know, for example, if there is tailings, is it contaminated? What's the biggest risk of the site? Um, and it's always something that we deal with first because it's prioritised. And then once we work out, what the biggest risk are, we sit down and go. “Okay, how can we manage this? That it's a cost effective way to manage this risk and to reduce the risk?” As I'm an Ecologist, a lot of work around how our work may impact the environment. For example, we quite often have micro bats living in abandoned mines. Particularly shafts and adits and my work is to work out how’s best to close or make safe those sites but incorporate the animals or plants or anything like that that might be in and around those sites.
Mitchell: A very, very important part of working on abandoned mine sites is the interactions with the various stakeholders.
Host: Here's Mitchell Thompson from Resources Remediation within Technical Services.
Mitchell: So very, very important to find out what they want, find out what their aspirations are and see if we can tie in those wants and aspiration is with the science behind rehabilitating mine sites. So for me at Collingwood Tim on a regular basis, we would call a stakeholder engagement meeting with the traditional owners and the elders. I spend a lot of time, particularly with the traditional owners on the ground as well, doing the ongoing rehabilitation of the mine. So that could be anything from water monitoring, basic civil earthworks, flora and fauna monitoring, basically whatever is required on site.
Amanda: The final part of the work that we're doing at Collingwood Tin is making safe the tailing storage facility and to make this a little bit more complex, the northern qual, which is an endangered species, is living in and around the tailings storage facility. So we've engaged an Ecologist to survey the population. Make recommendations on how we can protect the population and make sure there's habitat preserved into the future.
Host: Annaliese – what's it like to visit an abandoned mine site? Take us there!
Annaliese: So at the moment I'm looking at one of our mine water dams on the Baal Gammon mine site, and it's a beautiful turquoise blue. We're currently putting some lime in there to increase the pH. It's quite acidic. So we can hear in the background the pump that's pumping the water and mixing that lime in. And then we've also got an evaporator fan in the background that's just blowing water up into the air, trying to get nature to do as much as possible and help us out. So on this side, it's a lot about big focus at this time of year, is water management obviously far North Queensland coming into the wet season.
Um, and it's rumoured to be quite a big wet this year, so we've got to manage our water to make sure that when that rain does come, we've got a capacity to store it.
Host: What are some of the environmental outcomes as a result of this work?
Tania: One that comes to mind is a site up in Croydon, up in the Gulf of Carpentaria.
Amanda: One of the other challenges that we face what many of our sites is metal rich acid water. Um, that leaves the site, and that has the potential to impact downstream water use and have impacts on the environment.
Tania: We undertook some remediation works to reduce the contaminated water that was going into a downstream environment. A couple of years later, the landholder came to me and told me that he had seen a lot of Red Claw go back to a permanent waterhole which was downstream and a lot of fish life come back, which they hadn't seen for many, many years.
Amanda: If we were to release that water at a lower water quality like, what does that say about how the government as a whole regulates the industry? We've got to be able to stand up to that scrutiny as well.
Host: So, Tanya Mining in Queensland has been around for more than 100 years. How has the legislation changed over time?
Tania: The Environmental Protection Act was introduced in 1994 in 2000 and one with the amendments of the Environmental Protection Act. There was a lot more stringent requirements put on mining companies for rehabilitation and for their environmental operations. But despite that, 30 mines been abandoned in the last 20 years is still a significant amount. So because of that, there has been additional reform to the legislation that will lead to further improvements within the mining industry. So these reforms really deal with the financial risk to the state of sites becoming abandoned.
The reforms ensure that there is adequate financial provision set aside for operating mine sites across Queensland and also they ensure that progressive rehabilitation is done on operating mine sites as well.
Mitchell: It's not an overnight process, it's an expensive process and it's very resource demanding. The rehabilitation of a mine site needs to be incorporated into a functioning mine site, so as it's producing and as it's removing that resource, that rehabilitation needs to be factored in, because it's also significantly cheaper to progressively undertake the rehabilitation if you've already got machines and you've already got manpower on the ground.
Tania: It reduces the risk essentially of the site, defaulting and walking away. If you've undertaken progressive rehabilitation on the site.
Host: So why is it up to us to do this work? And why is it so important?
Annaliese: Resources releases the land for mining. We have DES who regulate the licence agreements or the licence obligations under that environmental authority.
Host: DES or D.E.S. stands for the Department of Environment and Science.
Annaliese: And then when the miner’s no longer able to satisfy the obligations of that environmental authority or that licence and they disclaim it, it kind of comes full circle and comes back to us.
Tania: There is a separation of duties for us to undertake the works. Regulators should be focusing on ensuring operators meet their requirements. And it is a conflict of interest, really, for a regulator to undertake those those works and engage contractors. Another reason why this work is really important is if mining communities see that there's legacy issues that haven't been dealt with, then they are unlikely to support future mining in their communities as well.
So it's really important that we clean up these legacies from the past to ensure that social licence into the future. We are leading in terms of the amount of financial investment and the size of the programme and the works that we do, and in saying that there's globally, there's a lot more work to do. And so, some of the work that we're doing in Queensland is being used to help inform the development of that international standard so that we can share out learnings across the world.
Host: I imagine for some people their curiosity gets the better of them. Do people actually seek out these old mine sites?
Amanda: Absolutely. Everyone goes to Mary Kay to get a photo because it was quite a bustling little town when the mine was in operation there in the eighties.
Host: What are the dangers for people who hang around an old mine site?
Amanda: Mary Kay in particular. There's residual radiation at the site, which you know if you're visiting for 20 minutes, it's probably not going to have any major health impacts, but it's certainly a risk. But with any of those open pits, you know they've been worked many years ago, and because they're not maintained or anything, there is risk: A of someone falling or there's rocks that fall, which can happen because it's not maintained, certainly something that the department don't want to promote.
Host: Is there a take home message that you'd like our audience to know today?
Amanda: The most challenging part of our role is to come up with those solutions that is going to make the site safe and address any of the issues.
Tania: I guess it's those little positive outcomes and the feedback from from landholders and community members, which is which is a highlight.
And I think the best part of our work is making those improvements on the ground and seeing change to these contaminated sites and improving these sites in terms of environmental outcomes but also improving the safety for our communities as well.
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Each podcast episode is produced for educational purposes only. The views, information or opinions expressed during the podcast are solely those of the individuals involved and do not necessarily represent those of the Queensland government
Last reviewed 25 September 2022