Lessons learned from the Aznalcóllar environmental disaster

On that April 25, 1998, the landscape was stained in black when almost all the elements of the periodic table spread through the Agrio and Guadiamar rivers, arriving at the doors of Doñana. Six million cubic meters of silt flowed through the breach in the lagoon, affecting around 6,000 hectares.

Bad maintenance facilitated the disaster, announced years ago by scientists and environmentalists. The Boliden-Apirsa company had just caused the biggest polluting accident in the history of Western Europe.

Despite initial bewilderment, recovery performances were excellent. The quick intervention to limit the affected area was successful, much more so than the idea of ​​moving the Prestige away. In this case, the damage was limited, as a much smaller leak ended up affecting a huge area.

The performance of the Superior Council for Scientific Research (CSIC) was fundamental, on the one hand, in advising the administrations on recovery tasks and, on the other hand, because it became a reliable source of information that contributed to generating the necessary tranquility to face the tremendous work that awaited us.

The lagoon still flows into the Agrio River, which gradually descends towards the national park.

In the same places that witnessed that massive transport of toxic sludge, Europe’s biggest contaminated soil cleanup operation would take place over the next three years.

Now, 25 years later, baseline contamination —although slightly higher than before the accident—is far from worrying levels. The area is clean and there are no risks arising from the accident for any living being, including people.

The recovery has been exemplary and is, in fact, a reference model at an international level. From the point of view of scientific knowledge there is a before and an after. Everything we know in the world of accidents of this type, we know about Aznalcóllar.

What still threatens Doñana

Although administrations have mostly followed the CSIC’s suggestions, two have been overlooked.

The pool continues to flow into the Agrio River which, little by little, descends towards Doñana.

Moving the Agrio riverbed away from the edge of the lagoon would be the solution that is also totally feasible from a technical point of view.

As a result of the accident, there were changes in regulations, both national and European, which today make it more difficult for something like this to happen again.

Read Also:  Low-Cost, Eco-Friendly & Long-Lasting: The Many Advantages of Bamboo in Construction

The second pendency is in the ‘Green Corridor’. Although it is a magnificent example of recovery of the contaminated riverbed and almost destroyed during depollution, from an ecological point of view it is not a functional corridor because its connection with the forest massifs to the north of the National Park has not been ensured and is, therefore, unable to connect them with Sierra Morena.

Again, this is technically possible, but not addressed at the time. Finally, it should be remembered that, as a result of the accident, there were changes in regulations, both national and European, which today make it much more difficult for something like this to happen again.

Unfortunately, as the Prestige case made clear, the intervention of CSIC investigators as advisors in crisis situations, which produced such good results in Aznalcóllar, far from becoming an example, remained an anecdote.

Today, 25 years later, the opportunity arises to reopen mining activity in Aznalcóllar. Personally, taking into account that the exploration is not foreseen in the open and that the extraction procedure does not generate those huge and dangerous rafts that were necessary in the past, it seems to me that the reopening is the only realistic opportunity for someone to pay for the inertization of sludge, assume the environmental liabilities and face the necessary challenge not only of not harming the environment, but of leaving it in a better situation, with higher levels of environmental health and biodiversity.

If that was the objective of the Junta de Andalucia and the concessionary company, the scientists who at the time worked on the accident would be very happy, because we would never have to do that again.

Miguel Ferrer is Research Professor at the Higher Research Council (CSIC) of the Doñana Biological Station, of which he was director from 1996 to 2000. He is also president of the Migres Foundation, since 2003; Member of the Council of Europe Group of Experts on Biodiversity and Global Change since 2001 and IPCC reviewer.

Recent Articles

Related News

Leave A Reply

Please enter your comment!
Please enter your name here