Phytoremediation’s potential in mine cleanup

Posted: September 19, 2025

Why might the world’s largest copper miner be in the business of growing cacti? Chile’s state-owned Codelco is building a nursery capable of producing a million native plants, including endangered cacti.   

It’s a region known for its prized, rare succulents. This year, Chilean police brought down a $1 million international cactus heist. But in Codelco’s case, the plants are destined not for a black market (unless crafty poachers get there first).

Codelco’s nursery initiative points to an emerging strategy known as phytoremediation: using plants to revegetate mine-impacted landscapes, and sometimes to extract contaminants. 

While a botanical approach to managing tailings may sound quaint, decades of interdisciplinary research have converged to accelerate phytoremediation strategies’ efficiency. Phytoremediation is not only an ecologically friendly and cost-effective strategy, but one increasingly applied in mining contexts worldwide.  

What is phytoremediation? A short primer

Phytoremediation refers broadly to the use of plants and their associated microorganisms to reduce environmental contamination in soil, water or air. In mining, two strategies are especially relevant.

Phytostabilization: Plants that can tolerate high concentrations of metals could be cultivated in mine tailings or waste rock, anchoring soils, reducing erosion and trapping dust. Some species can also immobilize metals in the root zone, reducing the risk of leaching into waterways.

Phytoextraction: Certain “hyperaccumulator” plants absorb metals into their tissues, which can then be harvested and removed. It is considered the most environmentally friendly way to rehabilitate contaminated soils.

Both strategies are considered especially effective for sites with lower or moderate contamination, where standard cleanup methods are either too costly or not feasible.

Why is phytoremediation emerging now?

Phytoremediation has been around for decades, but several factors are driving its increased relevance in commercial mining. 

• Advances in biotechnology and soil science
  The complex field of phytoremediation studies is receiving more and more academic attention. As a result, there is an increasing understanding of metal-tolerant species, soil amendments and plant-microbe interactions that make phytoremediation strategies more promising, even in hostile tailings substrates. 
• Economic incentives
  Phytoremediation is cheap compared to traditional, less sustainable rehabilitation methods. Commercial mines like Vale Canada’s Sudbury site have received attention for effectively using phytoremediation strategies at far lower cost than more energy-intensive methods used before. Following Vale’s success, other mining companies in Canada have pursued similar approaches.
• Regulatory and community pressures
  Scrutiny on the mining industry is up: this year, the International Council on Mining and Metals (ICMM) recently updated its Tailings Management and Integrated Mine Closure guides to emphasize environmental stewardship.
  At the same time, clients and neighboring communities demand more sustainable practices from mining companies. Codelco’s CEO has described initiatives like the company’s native-plant nursery as a direct response to public demand for stronger sustainability commitments. 

Limits and caveats

Phytoremediation isn’t a silver bullet, and is so far a complement to existing strategies. The complex field involves many challenges, beginning with finding the right species for the right metals, which vary by region.

Critics argue that phytoremediation’s benefits are a drop in the bucket compared to the scale of mining’s waste problem. In Codelco’s case, observers have labeled the cactus nursery initiative and other sustainability efforts as only marginally beneficial. And while plants in the initiative are noted to have been selected for their promise as hyperaccumulators, phytoremediation per se is not yet part of Codelco’s official sustainability directives.

Despite many promising trials, real-world implementation is in its early stages. Mining operators may hesitate to implement phytoremediation because of ambiguous ROI and the long timeframes of plant growth.

What’s next in phytoremediation?

Plants alone may not be able to clean up all of mining waste, but the fact that the world’s largest copper miner is investing in them matters. If a company of Codelco’s scale is willing to plant a million cacti as part of its cleanup strategy, that signals a shift in what’s considered viable rehabilitation—moving from academic demonstration into practical, cost-effective site management.

As the science continues to improve, plant-based solutions may grow from side projects into standard practice. At minimum, they offer a way to reduce costs and liabilities while meeting rising community expectations—and creating a more beautiful, regenerated landscape.