Not so long ago, when a quarry or mine reached the end of its economic life, the operator or owner simply walked away and left it. Quite apart from the obvious safety issues this left unresolved, there were environmental issues and the impact on surrounding land values – especially with quarries, many of which are in urban environments. Who wants to live next to an unused quarry? Nobody saw any reason to hold the previous owner responsible for rehabilitation and, likewise, local governments couldn’t afford to do it – so it just wasn’t done. Consequently many locations were left with dangerous, unsightly, big holes in the ground.
These days we view things differently. Now if you take up a lease for a mine or quarry, included in the operating conditions is the requirement for rehabilitation at the end of the lease. While rehabilitating a mine or quarry site remains a complex undertaking, at least there are laws in place to facilitate this undertaking.
The catch of course are those old sites that were simply abandoned.
Toowoomba Regional Council
Fortunately, many local governments are taking up the challenge of rehabilitation. A case in point is the Toowoomba Regional Council (TRC) which is rehabilitating the Bridge Street quarry in Toowoomba.
The Bridge Street Quarry was in production for over 100 years between the 1870s until 1994 when the TRC no longer required the site for extractive purposes.
In 2001 the TRC proposed a plan to redevelop the quarry site, and while this plan did not eventuate due to funding issues, the plan was revitalised in 2020. Planning and sourcing funding from the various levels of government are now underway.
For example, Texcel was recently involved in monitoring of the quarry walls to ensure their stability prior to undertaking further redevelopment.
What will the redeveloped site look like? Well, final plans are not yet available, so we don’t know, but perhaps we can get some clues by looking at a previous redevelopment in Toowoomba. What today is the Picnic Point waterfall site, very popular with local residents and tourists alike, was the site of a quarry from the 1800s.
While considering alternatives for a redevelopment, it is worthwhile looking at the imaginative solutions some people have come up with.
A fairly common solution is the one adopted by Moorabbin in Victoria. They took an old sand quarry and transformed it into parklands capable of sustaining a diverse array of species as well as recreational activities – now known as Karkarook Park. But it is very easy to argue that an old sand quarry is much easier to deal with than a hard rock quarry, so let’s look at some of these redevelopments.
The traditional approach is to block off the site’s drainage and allow the pit to fill with water. This can create not only recreational facilities, but also significantly improve the area’s biodiversity. A different take would be to allow the “big hole in the ground” to function as a flood retention facility.
But in other cases, not allowing the pit to fill up with water can provide other opportunities – such as the development of an interesting shopping centre like the Highpoint Shopping Centre in Melbourne. For a couple from Melbourne, not allowing the pit to fill with water convinced them to purchase an old quarry to establish a large creative and education program that allowed rehabilitation to be really the key driver. Incidentally, this same couple pointed out that the quarry site was significantly less expensive than a one-bedroom apartment in St Kilda or Brunswick! Quite another way to look at the opportunity.
The moral is that what can be done with an old mine or quarry site is limited by your imagination only.
As another interesting aside, there are apparently in excess of 80,000 abandoned mines and quarries around Australia! It is estimated that many of these old mine sites contain significant amounts of the so-called critical metals – nobody had any use for these metals in the past, but today they have become a critical resource for the high-tech industries (smart phones, batteries, etc). Yet another option for old mine sites.
Then, to illustrate the size of the opportunity, of the 80,000 abandoned sites, the number of mine sites that have been rehabilitated is extremely small:
- Queensland 0
- NSW 1
- Victoria 1
- South Australia 18
- Western Australia Unknown
- Tasmania 1
Why has South Australia done so well in this area? No idea, but perhaps we will make this the subject of another blog.
The next question is, why is rehabilitation such an environmentally challenging issue?
The original ecosystems have been removed and the original topography has been significantly changed.This results in a disrupted (sometimes irreversibly) ecological relations and a reduction in biodiversity. These changes will not only be felt in the areas directly involved in the quarrying, but also in surrounding areas. Consequently, the optimal land use of the abandoned mine or quarry should be determined by the characteristics of the nearby environment.
All of this means that the planning of these redevelopments takes time – lots of time. Getting the political consensus is the first challenge and the next is the very involved process of getting buy-in from everyone concerned. Then there is the funding challenge. Local councils simply do not have the ability to fund these projects by themselves, so buy-in from the State Government is usually required – yet another major challenge.
On the up-side, when these projects are completed, the results can be spectacular.