6 myths about tailings reprocessing (and why they’re wrong)

Tailings reprocessing is a hot topic in boardrooms at the moment. The risks of tailings storage are clear, and the financial burden is massive and growing. That’s why many miners are now considering reprocessing to reduce liabilities and find new sources of value within their business. 

Recovering metals from tailings is now more attractive than ever because of the range of technologies and processes that are available and proven to work. 

However, when we talk to mining executives, they often tell us “We looked into it, and it wasn’t viable because…” 

What follows is usually one of the many myths that get repeated in the industry as if they were fact. 

“Often myths get created within the business that become the reason why tailings reprocessing won’t work for them,” says Brent Slattery, COO of Future Element

“But when we examine their business more closely, we typically find that the assumptions they made aren’t accurate. Reprocessing is much more valuable than many people realise.” he explains. 

Here, we look at the 6 biggest myths around tailings reprocessing and explain why they are myths. 

Myth 1: You need high metal content to reprocess tailings profitably

“We just don’t have enough metal in our tailings to make it worthwhile”. 

This is the most pervasive myth we encounter.  

Everyone has a different idea about what metal concentration they need in their tailings for reprocessing to work at their operation. 

Why it’s a myth: 

“They usually have a preconceived idea of what the economic threshold is, and this is always different for different mines,” explains Brent. 

It can be a mistake to compare the metal content in your tailings to what you process in the mine.  

For example, people might think if their current ore is 1% copper and they’re only just making money with that, then they can’t possibly make money with tailings that have 0.3% copper. 

What they overlook is this: there’s more than one value lever to be considered. The value isn’t just in the metal. It’s also tied to the water, land, liability, insurance, and environmental bonding.

New Century Resources case study is explained further here. 

Even if a reprocessing project generates a negative net present value based on the lower metal content, you can still win because it reduces your liabilities. 

Also, the mistaken assumption is that you would always process the tailings in your current process plant. New technologies and processes can unlock metals and minerals in tailings that were assumed to be too low in grade to be viable. 

Myth 2: We already looked into it and don’t think it can be done

By now, most mines with large amounts of legacy tailings have investigated tailings reprocessing. They have conducted studies, collected the data and made a decision. It’s just not viable.  

Why it’s a myth: 

Usually, these studies are tightly constrained and lack the full suite of value levers to deliver value. The people conducting the study often don’t consider all the options and are too focused on one aspect of reprocessing or closure to see the potential value to the business. 

Brent says that the structure of business often limits these studies. “The study manager may know what needs to be done to deliver a successful tailings strategy, but it will often fall outside their role and scope.”  

Tailings reprocessing is often viable, but it could require changes to how a mine operates, for example. Changing the operating philosophy of their mine to introduce a new technology could seem impossible or unreasonable to a study manager focused on one narrow goal, such as mine closure. 

“Their job is to close the mine, not change how the mine operates. So, there’s no incentive for mine rehabilitation to happen early and make it economic. They’re not incentivised or measured on that,” says Brent. 

Similarly, mine closure or rehabilitation teams—constrained within specific engineering disciplines—often lack the visibility to evaluate a company-wide strategic option and understand the downstream value creation potential. 

Good tailings reprocessing studies require a confluence of tailings, water, closure, and operations, and most people lack the breadth of experience to tie all those aspects together. 

“We recommend that mines establish ‘economic rehabilitation’ teams with experience and expertise in business development, finance, metallurgy, technology, and conventional tailings disciplines.” 

If given a clear mandate to access all available value levers, this type of team can conduct a study process that recognises and solves the challenges of economic rehabilitation concurrently with ongoing operations.  

That’s how the business can create more value, far beyond simply minimising closure costs and liabilities. 

Myth 3: If there was value to extract, someone would have done it already

You can understand why people might think this. Many very smart and capable people have worked at the mine over the years. Surely, if reprocessing was worth doing, someone would have already done it. 

Another comment we hear with a similar sentiment is: “Our process plant is extremely efficient, so it’s not worth looking at what’s left over.” 

Why it’s a myth: 

Most processing plants aren’t run for maximum efficiency. That’s because extracting the highest recovery possible doesn’t always deliver the best economic outcome using the plant and infrastructure in place.  

Operators always make a trade-off between throughput and recovery. For example, let’s say maximum recovery is 90% and your mine processes 1Mt of copper p.a. You get 900kt of copper p.a. But what if at 85% recovery you can put 1.2Mt through? That’s 5% less recovery for 20% more throughput.  

This was exactly the rationale for the previous owners of the Century mine, which created the initial tailings opportunity for New Century Resources. 

When you commission a new plant, there’s often pressure to maximise cash flow to recover the capital cost and repay debts quickly. Tailings reprocessing isn’t constrained by that – its business case has different success metrics.  

For example, the payback period of tailings reprocessing could be 10 years if it’s achieving another strategic objective such as progressive rehabilitation. When you know how much material is there and it’s easily accessible, you can process it slower and get a higher recovery rate. 

There are also technology changes that make it worth considering. There may be new technologies to apply to the tailings that the current process plant can’t use. It often makes good financial sense to design a new plant to maximise efficiency for the tailings reprocessing, which creates an entirely new proposition. 

And finally, there are changes in macroeconomic conditions, with new industries and new focuses on metals that didn’t exist when the mine was originally developed. This creates opportunities for additional value to be generated. 

Myth 4: My current plant doesn’t have the capacity to reprocess tailings

Everyone assumes that their current plant is the only way to reprocess their tailings.  

“But we don’t have enough capacity and the tailings would displace the primary feed,” is something we hear a lot. 

There’s an implicit assumption that they couldn’t just build a new plant for reprocessing. 

Why it’s a myth: 

The assumption that they can’t build a new plant is just that, an assumption. 

“When miners think this way, it’s mainly a mental constraint,” says Brent. “If the value is big enough you can make a business case for it.” 

New technology can make a new plant viable, especially when a plant is designed and tuned only for tailings. 

“We’ve looked at many business cases where you can build tailings reprocessing plants up to $250M and they’re still viable.” 

This is further enhanced if tailings are reprocessed and rehabilitated progressively, as the tailings reprocessing plant benefits from established infrastructure of the operating mine, which lowers the capital and operating costs required. 

Myth 5: We can’t build an investment case internally

We’ve seen this many times. When comparing potential projects, expansion projects always win over a tailings project on IRR, so they get prioritised.  

A tailings reprocessing project may look attractive but still can’t compete with other projects within the business as they all compete for capital. 

Why it’s a myth: 

This is a myopic view. Tailings reprocessing is still an attractive investment, but in comparison, mines usually have other higher returning options. The return on tailings reprocessing is usually good enough that other businesses would invest in these projects if given the chance. 

“Mining operations are built around maximising net present value, so the competition for capital means economic recovery of metals from tailings is deprioritised,” explains Brent. 

Future Element has a track record of raising funding for tailings projects and has cultivated a base of investors who are interested in the financial and ESG outcomes created by tailings reprocessing projects. 

This opens up opportunities for external investment that allows miners to fund economic rehabilitation without compromising on returns from their capital constraints. 

Myth 6: Our core business is mining, not reprocessing

You might be thinking: “Yeah, this all sounds great, but we don’t want to be distracted by reprocessing. Our core business is mining.” 
And you’re right. This one isn’t a myth. It’s a sound business strategy to focus on core revenue activities.  

However, it doesn’t have to be a choice between the two. 

Why it’s a myth: 

The myth here is that you need to make a binary decision to do either reprocessing or mining.  

Can you do both well? Yes.  

With a specialist partner to run the reprocessing operation, you can focus on mining and benefit from tailings reprocessing without distraction. 

Reprocessing can operate autonomously and in parallel to the main operation. 

Brent explains how this works in practice: “When we partner with you, Future Element is responsible for the entire tailings reprocessing operation. We understand the interfaces and inputs and understand how it all contributes to the sale of the final product.” 

In a stand-alone economic rehabilitation operation, we can handle all of the following so there’s no disruption to your existing operations: 

  • Tailings remaining & transport 
  • Metal & mineral recovery 
  • Tailings dewatering 
  • Tailings deposition 
  • Water treatment 
  • Rehabilitation 

Myths busted?

There are plenty of reasons you might think that tailings reprocessing can’t work at your site. Hopefully we have shown you new ways to consider these from a fresh perspective.  

Tailings are an essential part of mining and that isn’t going anywhere, but the way the industry approaches tailings management is changing rapidly. 

We help forward-thinking mining companies move towards a future without tailings dams. So they can clean up the water and land while creating strong economic growth in their business. 

Reach out for a confidential discussion to find out what the possibilities are for your operation.