VALVERDE DEL CAMINO – Experts are warning of a potentially catastrophic situation at the colossal mining dams of Riotinto in western Andalucia. The dams, nearly 42 metres high, currently hold 182 million cubic metres of toxic sludge.
Atalaya Mining, the mining company, has recently submitted plans to raise the existing dams, which would result in an increase of 107 million cubic metres of waste material from the copper mine. If these dams were to fail, it would cause a flood of 63 million tons of toxic sludge. That is ten times the volume of the infamous environmental disaster in Aznalcóllar in 1998, where a dam break released 5.5 million cubic metres of toxic sludge and 1.5 million cubic metres of acidic water containing high levels of heavy metals and other toxic substances into the Agrio and Guadiamar rivers, spreading over a distance of 40 kilometres before being contained.
Safety of the dams questioned
The safety of the Riotinto mining dams has long been a cause for concern. El Pais reported in 2019 that researcher Steven Emerman from the University of Utah predicted a 95% likelihood of the dams breaking within the next 20 years. He emphasised that authorities should evacuate the area to prevent potential loss of life and an ecological disaster.
Experts also point out the latent risk of “liquefaction,” where the stored material transitions from solid to liquid, increasing pressure on the dam walls. This can eventually lead to a structural failure. Ecologists claim that “Atalaya Riotinto discharges sludge into the dams with a liquid content of 70%,” even though “environmental and mining permits require the sludge to be thickened below 50%.” This accelerates “the possibility of dam wall failure.” Additionally, the same organisations state that “the company has not even built the planned sludge thickening plant.” Moreover, this leads to accelerated deterioration and insecurity of the dams holding the sludge.
Fear and concern among the population
The threat of a potential environmental disaster at the Riotinto mines has caused fear among the population of nearby towns and villages. In an article in El País, they express concerns about the consequences for the environment, tourism, and fishing, fearing that the region’s economy will be severely impacted.
If the Riotinto dams were to fail, it would lead to a catastrophic flood spreading over a distance of 111 kilometres. The toxic sludge would flow through the Odiel River, inundating various areas, including parts of the city of Huelva.
Experts estimate it could take approximately just 10 hours for the sludge to reach the mouth of the Huelva River and the Atlantic Ocean. The consequent impact on the environment would be devastating, with potential significant damage to the flora and fauna of the affected areas.
Furthermore, the economic impact of such an environmental disaster would be enormous. The Huelva region is known for its tourism and fishing, both of which would be severely affected by the flooding of toxic sludge. Local businesses are concerned about the consequences for their establishments, including Antonio Bonilla, owner of a brewery near the mouth of the Huelva River. He emphasises that the arrival of the sludge would not only ruin his business but also harm the entire city of Huelva.
Mining Company’s response to criticism
Atalaya Mining, responsible for the operations at Riotinto, claims that the dams are “100% safe” and that they have complete confidence in the design of the expansion. They criticise the “false catastrophic predictions” and “unfounded accusations” that, according to them, cause unnecessary panic. Atalaya Mining is collaborating with the Consejo Superior de Investigaciones Científicas (CSIC) of the government to develop a platform that integrates various technologies to detect potential incidents early.
Government emergency plan
Meanwhile, local authorities have developed an emergency management plan for Riotinto in the event of a dam breach. This plan is currently in the final stages of completion, but its contents have not been disclosed yet.
“The government is not listening to the warnings from independent experts, they will find out and be held accountable if a breach occurs,” criticises Isidoro Albarreal, a mining activist at Ecologistas en Acción.
Riotinto as a symbol of sacrifice
The situation in Riotinto raises broader questions about the price paid for mining activities. Lucas Barrero, a researcher at the Autonomous University of Barcelona, calls Riotinto a “mirror of sacrifice areas.” He highlights the direct consequences of mining and the pollution generated by the industry, referring to other problematic sites in the region such as the landfill in Nerva and the fosfoyesos ponds near Huelva. Barrero states that the economic benefits often go to multinational corporations, while local communities bear the burdens.