The rupture of the Riotinto Project dam could cause a toxic spill 10 times higher than the 1998 Aznalcóllar catastrophe

The rupture of the Riotinto Project dam could cause a toxic spill 10 times higher than the 1998 Aznalcóllar catastrophe

Ecologists in Action denounces that the mismanagement of the dam by Atalaya Mining is accelerating its deterioration and insecurity and demands that the Junta de Andalucía not look the other way.

Populated areas of Gibraleón and Huelva could be flooded by a toxic discharge wave of up to 5 meters, not ruling out the loss of human lives.

Ecologistas en Accion warns that the Riotinto Project's sludge dam has already overflowed with the past rains in April. In the event of a rupture, it could discharge a combined volume of contaminated water and sludge of 66.28 million m3, according to calculations made in October 2014 by the company AYESA for the mining company Emed Tartessus, currently Atalaya Mining. This would be more than 10 times the amount of toxic sludge that the Boliden pond dumped in Aznalcóllar 20 years ago, which put the Doñana National Park at serious risk.

The Riotinto Project dam, at the time of the stoppage of mining activity in 2001, occupied 530 hectares and contained 340 million tons of waste. It is made up of three sections arranged in a cascade, called Gossan (already clogged), Cobre (started in 1970 and increased in 2016) and Aguzadera (started in 1987 and increased in 2016).

The breakage of one of these three sections could cause a chain break of all. In any case, the mud would fall from heights between 46 and 64 meters (depending on the breaking point), into the Rejoncillo stream and / or the Aguzadera ravine, and in just over 30 minutes the Odiel river would arrive.

The 2014 failure study only foresees breaks, separately, of the Copper or Aguzadera section. However, the current mismanagement carried out by Atalaya Mining is causing a high-risk situation in the Aguzadera section, the failure of which could drag copper sludge by suction.

The content of these sections includes -in addition to mining waste- other highly toxic waste from the Huelva chemical pole, which were illegally deposited during the past decade of the 90s, in the same way that these chemical waste appeared in the Aznalcóllar spill on 25 April 1998.

Ecologists in Action denounces bad practices by Atalaya Mining in the management of the dam, which is accelerating its deterioration and insecurity. They are not respecting the safe distance of 50 meters of beaches between the water and the retaining walls, which indicates that they have far exceeded the allowed capacity, and the water is eroding those walls very dangerously.

This is due to the fact that Atalaya Mining is not thickening the sludge before dumping it into the dam, in breach of the obligation established in the environmental authorization of March 2014 and in the authorization for the restart of mining activity of January 2015. Both require reducing below 50% the water content in the sludge.

To save costs, Atalaya Mining have not even built the sludge thickening plant and is pouring it into the dam with a liquid content of 70%. It has also modified the sludge discharge system in the dam, reducing costs to the detriment of safety.

The 'spigotting' system used causes these excessively liquid sludge to fall very close to the retaining walls, which have also been re-built with techniques and materials similar to those used in the battered Aznalcóllar raft. In this way, the physical system of dumping by means of ‘sand cyclone’ is violated, which guaranteed greater consistency of the re-growth.

Ecologists in Action also denounces the actions of the Junta de Andalucía in relation to these events and asks it not to look the other way. The Junta de Andalucía knows and allows the breaches of Atalaya Mining. In April 2016, the Huelva mining authority agreed to stop the sludge dumping activity, due to non-compliance with the thickening conditions, but in just three weeks the General Directorate of Mines lifted this stoppage, allowing for the last two years the discharge of liquid sludge, and thereby becoming jointly responsible for the future catastrophic consequences that may occur.

Access to infographics and the chronology of the Riotinto dam:

More information: Isodoro Albarreal, 626 745 403

Video: Bento Rodrigues Mine (October 2020).