Picture two copper mines on the edge of a farming district. At the first mine, now at the end of its life, overburden, tailings, and waste rock is simply fenced off and left in place, while drainage slowly leaches metals and excess sulfate into the creek below. Over time, the mining company is forced to keep paying for active water treatment, decade after decade, just to keep contaminated water from reaching downstream farms and town supplies.

At the second mine, wasted production materials are carefully placed on leach pads. Drainage is directed through a series of treatment wetlands which are intended to raise pH and support metal settling, helping to filter the water before it leaves the site. The integration of lower-intensity, nature-based treatment methods reduces long-term construction and labour costs, ultimately contributing to a landscape that can be returned to its original pre-mining condition for grazing, wildlife, and cultural uses.

Where one mine becomes a stranded liability with treatment costs that never truly end; the other becomes a functioning landscape that can be safely released and re used.

As mining accelerates to meet surging global demand for critical minerals, the sector is confronting a parallel reckoning: how to manage land, water, and communities after extraction ends. The world’s 24 largest mining companies now carry an estimated US$78 billion in mine clean up and closure liabilities — a total that has grown by 82% over the past decade and now equals around 42% of the industry’s long term debt.

In Canada, closure timelines are stretching so significantly that only a small number of mines have ever been fully signed off and returned, with most remaining in care and maintenance or under indefinite monitoring. Globally, of 57 mines closed since 1945, just five have been fully released for next use. Investors are taking note: a coalition representing roughly US$18 trillion in assets has launched a 10-year plan to tackle underfunded closure and post closure liabilities and to build long-term environmental and social risks into capital allocation decisions.

Against this backdrop, nature-based solutions (NbS)—practical actions that protect, restore, and manage ecosystems and the communities that depend on them—are moving from the margins of mine planning to the centre of strategic decision making. Once treated as add-ons late in the process, NbS are increasingly recognised as essential site infrastructure, helping deliver cleaner water, more stable landforms, regulatory certainty, and post closure economic value.

But one lesson is becoming clear across markets: NbS only deliver their full value when they are designed early in the life of mine.

A Shared Platform for Nature, Mining, and Communities

This shift is prompting closer alignment within the GISI Consulting Group, between Palladium and GEI, as both teams work with mining companies on wide-ranging problems. We spoke with two of our experts who are exploring ways that both teams can collaborate in a more integrated way with mining companies to embed NbS into mine planning, operations, and closure — not as an afterthought, but as an integrated system.

“Nature-based solutions stop being ‘nice to have’ when you realize they can replace expensive infrastructure, streamline regulation, and shorten closure timelines,” says Sarah Skigen-Caird, Ecology Division Manager at GEI. “But that only happens when they’re engineered properly and introduced early — not bolted on at the end.”

The Cost of Leaving NbS Too Late

GEI’s experience across North America shows a consistent pattern: when NbS are introduced late in the project lifecycle, mine closure timelines tend to become longer and more costly. Delayed integration often leads to extended bond release periods that tie up millions of dollars in capital, higher remediation and treatment expenses, and missed opportunities to naturally achieve water quality objectives and land reclamation standards.

By contrast, when NbS—such as wetlands or natural streamside buffers— are designed early to deliver dual benefits (for example, improving water quality and meeting discharge requirements), they can replace expensive engineered treatment plants and accelerate regulatory sign-off.

“We’ve seen cases where restoring wetlands allowed a mine to meet water quality standards without building a multi-million-dollar treatment facility,” says Skigen-Caird. “That’s when NbS become real infrastructure.”

From Closure Risk to Economic Transition

For Palladium’s Meg Kauthen, the question extends beyond compliance: what should the land become, and who benefits? “Globally, our team has delivered NbS programs that combine landscape restoration, economic empowerment, and investment attraction—from large-scale reforestation and climate-smart agriculture to Indigenous-led land stewardship and blended-finance platforms.”

That experience is now being applied directly to mine closure.

In Colombia, Palladium is working with communities and industry partners to transition coal mines approaching closure into cocoa-based agroforestry systems. The model will restore soil and biodiversity while creating a new industry, supported by partnerships with major global chocolate producers seeking sustainable supply.

“Closure doesn’t have to mean walking away from land that still has value,” adds Kauthen. “By combining nature-based solutions with market access and capital, post-mine land can support new industries that are good for nature and good for communities.”

Designing Better Systems—Earlier

What differentiates the Palladium–GEI approach is not more studies, but bringing economists, environmental scientists, and engineers together early—so ecological function, community priorities, and future land use are designed in from the start, before options narrow and costs rise.

“When you understand the landscape before you disturb it, you can design closure as a transformation—not just a clean-up,” Kauthen explains. “The next generation of mining leadership will be defined not only by what is taken from the ground, but by what is thoughtfully left behind—for nature, for communities, and for the economies that follow.”