Huge toxic mine water spill hits Andalucia

Spanish environment minister promises "immediate action" after leak engulfs farmland

Thousands of hectares of Spanish farmland were engulfed by highly acidic, toxic waters over the weekend, after a reservoir holding 5m cubic metres of liquid waste from pyrite mining operations ruptured. The leak has sparked international interest as waters have threatened to poison the Coto Doñana nature reserve, a UN world heritage site, on the coast of Andalucia.

"A sad day for nature conservation" was the description of Isabel Tocino, Minister of Environment, as she visited the devastation caused by the failure of the mine's earth dam near the village of Aznalcóllar, 45km from Seville. The Minister promised immediate action and a thorough analysis of the causes of the disaster.

The mine is operated by a Spanish subsidiary of the Canadian-Swedish Boliden company, and the reservoir has already been the subject of legal complaints by conservation organisations. Juan Carlos de Olmo, secretary general of WWF, claimed that the suits, which were filed as long ago as 1995, had become stuck in Spain's "saturated" judicial system and that nothing had been done.

Both the national environment ministry and the Andalucian regional government are now launching inquiries into the causes of the ecological catastrophe and the mining company is being investigated by the Guardia Civil, the police organisation responsible for the environment.

Most of the contents of the storage reservoirs, a mixture of highly acidic water and heavy metal salts, poured out of a 50 metre-wide breach in the dam and across agricultural land into the river Guadiamar, which borders the Doñana national park. One of the most important wetland sites in Europe, Doñana is the breeding ground for hundreds of thousands of birds and a stopover for millions more on their annual migrations.

The worst of the toxic floodwaters have been diverted from the channels linking the Guadiamar with the wetlands. However, the region's tidal nature means that flushing the waste out to sea via the River Guadalquivir, of which the Guadiamar is a tributary, will be a long-term process. It is very unlikely that the Doñana ecosystem can avoid being affected sooner or later, say environmentalists.

The 4-5,000 hectares inundated by the muddy water with a pH value of about 2 are expected to be unusable for generations to come. Orchards, cotton plantations and rice paddies are covered in sulphurous mud laden with copper, lead, silver and zinc salts. Villagers have been warned not to drink water from wells, and cattle and sheep have been moved from the area.

Follow Up:
Spanish environment ministry, tel: +34 1 597 7000; Andalucian environment ministry, tel: +34 95 448 0216.

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