Solve pollution. Save lives. Protect the planet.

Pure Earth implements award-winning solutions to manage and reduce mercury contamination from gold mining tailings

Through these efforts, we are actively working to reducing the amount of mercury that is released into the environment. Join us in our commitment to safeguarding our planet’s health and well-being.

About Tailings Management

At Pure Earth, we advocate for the responsible management of mercury from artisanal and small-scale gold mining (ASGM) operations and implement award-winning technologies to capture mercury from tailings, a waste byproduct of mining. 

Tailings are the wastes produced from gold extraction and they contain high amounts of heavy metals, such as mercury. Mercury-contaminated tailings from mining operations, especially artisanal and small-scale gold mining (ASGM), are one of the main ways that mercury is released into the environment. The lack of management and control of tailings poses a major threat to human and environmental health. 

Using Copper Plates Technology to Capture Mercury from Tailings

After a technical analysis of existing technologies, Pure Earth identified copper plates as the most viable technology for capturing mercury from tailings generated by artisanal and small-scale gold mining (ASGM).  Pure Earth then conducted research to develop simple and affordable plates that could be disseminated to artisanal and small-scale gold miners and processing centers in Colombia to remove mercury from tailings before the gold cyanidation  process.

The copper plates technology involves the use of copper plates covered with a thin electrolytic layer of silver and other metals to retain metallic mercury drops from the tailings. This technology is easy to implement and low cost, capturing up to 84% of the metallic mercury present in the tailings under ideal conditions. It requires low operating resources in order to install it in operating plants.

Learn more in our report Promoting the recovery and responsible management of mercury in contaminated tailings from artisanal gold mining in Colombia: Implementation and economic plan for the use of copper plates, which was funded by the United States Department of State. Click here for the Spanish version.

Read: Trapping a Slippery Foe in The Chemical Engineer

Pure Earth Colombia Wins Award for Copper Plates Technology

In December 2022, Pure Earth’s breakthrough copper plates technology was named one of the top winners of the global Artisanal Mining Grand Challenge competition. The solution is capable of removing as much as 84% of mercury from waste tailings from artisanal and small-scale gold mining.

The prize money will enable the team to conduct more tests to ensure that the technology can be used by miners in remote areas that do not have regular water and electricity services.


Responsible Management of Mercury-Contaminated Tailings

Pure Earth Colombia developed a technical protocol for tailings management, which presents safe alternatives for handling, transporting, storing, treating and finally disposing of tailings. This protocol is a fundamental part of the base reference for the tailings management document promoted by the Minamata Convention. 

Read the English Version

Read the Spanish Version

In June 2023, Pure Earth delivered the first temporary mercury storage unit in Colombia to the Corporación Autónoma Regional para la Defensa de la Meseta de Bucaramanga (CDMB) as an environmental authority. The delivery of the storage unit is part of the technical cooperation agreement between Pure Earth Colombia and the U.S. Department of State for the promotion of the recovery and responsible management of mercury-contaminated tailings from artisanal gold mining in Colombia.

Pure Earth’s Tailings Management Solutions By the Numbers:

Our Impact


1100 miners trained in mercury-free techniques.

3750 children, community members, health workers and government officials educated.

Miners, especially women, report increased earnings.

Latin America
Latin America

310 miners trained in mercury-free techniques

550 mining community members and health workers educated

110 mercury sites identified and assessed

10 hectares of rainforest stripped by gold mining restored


200 miners trained in mercury-free techniques

1500 government stakeholders, health workers, miners and community members educated

85 mercury sites identified and assessed

100 retorts/70 water-box-condensers distributed, reducing mercury emissions by 4750 kgs annually

Women’s Working Group organized to give artisanal women miners opportunities to earn more with mercury-free gold


250 mercury sites identified and assessed

10 communities trained to reduce mercury use