The mining contamination with heavy metals in Alto Mañihuales, a rural locality in Aysén surrounded by mountains and native forest, has once again become the focus of environmental concern following new information about the activity of the El Toqui operation.
Although the problems were detected more than a decade ago, complaints indicate that leakages of heavy metals continue to affect soils, watercourses, and wildlife in the region.
Since 1983, mining exploitation has left accumulations of industrial waste in various areas near rivers and streams. However, public reports released since 2015 have already warned about the presence of contamination in the environment and in biological samples taken from local inhabitants.
Additionally, residents of Alto Mañihuales claim that the lack of preventive measures and constant monitoring exacerbates a situation that directly impacts the environmental quality and the rural activities of the community.
Judicial rulings and sanctions for environmental non-compliance
In this context, the Court of Appeals of Santiago recently confirmed a sanction against the company Minera Pacífico del Sur, the current holder of the El Toqui project since 2020. The resolution requires the company to pay more than 12 billion pesos linked to guarantees for executing the environmental closure of the mine.
Furthermore, the firm will have to face another financial sanction for non-compliance related to the quotas allocated to the closure plan. The case had already been ratified previously by a civil court, although the judicial process extended over months.
On the other hand, environmental organizations and residents reported administrative delays and maneuvers that allegedly delayed the implementation of urgent measures to contain the contamination. Simultaneously, observations from the Superintendence of the Environment remain in effect due to lack of monitoring and absence of regulatory information.
The impact of heavy metals on rivers and ecosystems
One of the most concerning issues is the tailings dams used to store mining waste. A technical report revealed that the Confluencia dam accumulated up to three times more contaminating material than allowed, also operating for longer than originally authorized.
This is compounded by the results released by the Patagonia Ecosystem Research Center, which detected arsenic levels far exceeding accepted values for drinking water in the San Antonio de Alto Mañihuales stream.
The heavy metals represent a critical threat to ecosystems because they remain in the environment for decades. Substances like arsenic, lead, or mercury can accumulate in fish, vegetation, soils, and animals, altering entire food chains.
Additionally, these contaminants reduce aquatic biodiversity, affect microorganisms essential for ecological balance and deteriorate water quality used by rural communities and wildlife.
Dead livestock and growing concern among residents
Meanwhile, rural producers reported the death of animals in fields near the mining activity. A resident recounted that during 2024 he lost several cows and that veterinary professionals suspected heavy metal poisoning due to the condition of the organs analyzed.
However, the inhabitants question the lack of permanent studies that would allow determining precisely the extent of the contamination. According to them, the official controls over water and soil are insufficient and often conducted during times of the year when leakages decrease.
Finally, human rights organizations warned that the absence of concrete responses could represent a violation of basic rights for the families of Alto Mañihuales, who continue to demand
