The residents of Tierra Amarilla , a small city in the Atacama region in northern Chile , woke up at the end of July with an unpleasant surprise. A huge sinkhole 32 meters in diameter and six meters deep had emerged a few kilometers from their home.
This hole has increased its diameter to 36.5 meters in a week and has caused the mobilization of local authorities and led the mining regulator Sernageomin to suspend the operations of a mine in the Candelaria district.
This is what we know about this sinkhole.
How did the sinkhole come about?
These types of sinkholes can arise from natural causes or as a result of human activity. One of the reasons is the heavy rains that fell in the area in July.
“You have several layers in the ground and there are several ways in which the water can erode,” Chilean geophysicist Cristian Farías, director of Civil Works and Geology at the Catholic University of Temuco, told BBC Mundo.
“When a lot of rainwater falls on soils with a high level of gypsum, the water percolates and erodes the entire lower part for several days, which makes the higher part less sustainable and ends up causing a collapse,” he explained.
A second hypothesis points to the influence of mining activity in the area.
“The preliminary information that is handled points to the intervention of the mining company that overexploited minerals in that area,” explained Cristóbal Muñoz, director of the informative NGO Red Geocientífica de Chile to the British media.
The mining intervention could have destabilized the soil by diverting the groundwater from its natural course and emptying the aquifers, creating spaces that favor the ground giving way and falling under its own weight, forming the sinkhole.
The miner said in a statement that it had been informed in due time to the regulator.
“We want to be emphatic that, as reported by Sernageomin, this hypothesis has not been determined, to date, as the direct cause of the sinkhole. The hydrogeological and mining studies will provide the answers we are looking for today,” the company said.
“The different events that could have caused the sinkhole are being investigated, among which the abnormal rainfall recorded during the month of July is relevant,” added the Lundin unit.
Who owns the mine that operates nearby?
The Alcaparrosa underground belongs to the Minera Candelaria district, an operation that feeds from an open pit and three underground wells, according to the company’s website. The sector as a whole is known as Minera Ojos del Salado.
Canadian miner Lundin owns 80% of the property, while the remaining 20% is held by Japan’s Sumitomo Metal Mining and Sumitomo Corporation.
What has been the reaction of the inhabitants of Tierra Amarilla?
The huge hole surprised the nearly 13,000 inhabitants of Tierra Amarilla.
Cristian Zúñiga, mayor of Tierra Amarilla, explained to local media that the population has always feared incidents due to mining operations in the area.
“This huge sinkhole is something that had not been seen in our community. We request that it be possible to clarify why this event occurred, if the collapse is the product of mining activity or if it is of another nature,” he said.
On Sunday, 800 inhabitants of Tierra Amarilla protested to demand that the mining company be punished for this sinkhole.
The Chilean government will seek to apply harsh sanctions to those responsible for a huge sinkhole that occurred near a copper mine owned by Canada’s Lundin in the north of the country, Mining Minister Marcela Hernando said on Monday.
“We are going to go to the ultimate consequences to sanction, not only fine because sometimes the State has very few tools and the fines are insignificant, but not only the fines, but the serious consequences that this can bring to the mining company have to be exemplary “, he added.
Safety in mining, another topic to discuss
The sinkhole has brought to the table another important issue for the Chilean copper industry: safety in the mines and the impact it can have on the population.
“What if that sinkhole happened in a town? What if it happened in a job site? What would we be lamenting today? It could perfectly have happened,” said Chilean President Gabriel Boric on Wednesday.
Boric assured that the Chilean government will work on the ratification of Convention 176 of the International Labor Organization (ILO) on health and safety in mines to guarantee the well-being of workers in the sector.
For several years, trade associations as well as parliamentarians from the world’s largest copper producer have asked for government support for the agreement adopted in 1995, which includes a series of guarantees in favor of workers, establishing the duties of the State to adapt local legislation to certain standards. .
“During this ratification process of (agreement) 176 we are going to have a national policy on safety and health in the mines and that the families of miners and miners can also rest easy,” Boric said during an act to commemorate the Day of the Miner and Miner.
“Although accident rates have decreased in the last 10 years, we still have a lot to do,” he added.
The president affirmed that last year there were 20 deaths in accidents in the sector, for which he underlined the need to reach the goal of zero fatalities.
In July, two operators of the construction of projects of the state giant Codelco, the world’s largest copper producer, died in different accidents, which once again turned attention to compliance with industry safety standards in the South American nation. .
With information from AFP and Reuters