Mine Tailings Storage: Safety Is No Accident

The tailings dam at the Los Frailes gold-copper-lead-zinc mine, located at Aznalcóllar near Seville, failed in April 1998 Case study: Los Frailes, Spain, 1998

(Figure 19). It released approximately 5.5 million cubic metres of acidic, metal-rich water and approximately 1.3 to 1.9 million

Valverde del Camino

Aznalcóllar mine storage facility failure

A slab of soil beneath the dam slid approximately one metre towards the Río Agrio. The front of the slide was about 20 metres wide, and it was located in the area of the junction of the two impoundments.

Aználcollar

The dam cracked and broke.

Sanlúcar La Mayor

La Palma del Condado

Niebla

Bollullos Par del Condado

Aznalcázar

Almonte

Between five and seven million m 3 of contaminated slurry spilled through the gap.

This caused the bed of the Río Agrio to rise locally by three metres.

S PAIN

Parks designed after tailings spill Parks present at time of tailings spill Location of Los Frailes tailings spill Area of spill

Sanlúcar de Barrameda

Jerez de la Frontera

L ÓPEZ , 2017 6 km

Rota

Source: El País of May 14, 1998, WISE 2015, UNEP-WCMC.

Figure 19. The tailings dam failure at the Los Frailes gold-copper-lead-zinc mine

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