Endesa : fills its old mines with colour

As Pontes: the largest lake in Spain

During the mining period in As Pontes, Endesa designed and worked towards the future of the natural space occupied by the mine. This site in Galicia is, without doubt, the most emblematic restoration project, receiving numerous international awards and accolades.

The area once occupied by the mine pit is now the largest lake in Spain: 865 hectares and 547 cubic hectometres of water, with various swimming and leisure areas, where water sports can be enjoyed. The exterior spoil tip, where the sterile material from the site was accumulated, is now a natural area with a biologically diverse vegetation cover that has been colonised by autochthonous fauna in a natural process. Recent studies identified 217 plant species and 205 animal species.

In the other mining centres, the restoration work has enabled 2,360 hectares to be recovered for agriculture or the development of autochthonous vegetation and local fauna, despite being semi-arid environments in which reforestation is difficult.

Puertollano is particularly significant, where, once restored, 560 hectares have once again been used for agro-farming purposes, with a higher productivity than the surrounding unaltered land. Today it has a plantation of 28,000 olive trees, producing on average 250,000 kg of olives per year, which in turn yield an excellent quality olive oil. Of the 560 hectares restored, 244 have been used for pastureland and cereals, 126 for olive groves, 9 for fruit trees, 77 for Mediterranean forests, 96 for mining lakes and 27 for autochthonous reforestation and the introduction of fauna in these areas has already been identified.

In Andorra, despite the aridity of this area, cereal crops were grown here during an initial stage, a solution which was then replaced with plantations of fruit trees, olive groves and vineyards, where the area's own wine is being made under the label of 'Viña Alloza'.

Of the total area restored in the old mining centre of Peñarroya (835 hectares), there are 92 hectares of mining lakes, which have become an important haven for water birds.

A sustainable restoration

In order to guarantee the sustainable restoration processes, the chosen mining method was the back-filling method, which enables simultaneous mining and restoration works to be carried out. This means the mining project does not have to be completed before work can commence on restoring the entire affected area.

During this process, both the exterior and interior spoil tip have been shaped in such a way that they blend into the surrounding topography. They are then covered with topsoil, fertilised and planted with autochthonous vegetation. The final restoration phase for the mining project is the recovery of the final pit, normally by storing water.

The success of sustainable restoration lies in striking a balance between the mass of water, the development of the vegetation on the shores and the colonisation of autochthonous fauna. This balance has been achieved at As Pontes, Peñarroya, Andorra and Puertollano, four natural restored spaces that are perfect examples of sustainable development; the details of this project can be found in the aforementioned book, introduced by the well-known environmentalist, Joaquín Araujo.