The space occupied by the Terrera Nova is already taking shape
We have given value to the salt of the mine waste landfill, removed the mountain of rejected material and are restoring the freed land
The restoration project for Cardona's Terrera Nova, which Ercros launched in 2015 and is expected to be completed in 2027, has allowed 20 hectares of land to be recovered, decontaminated from salt and its morphology to be assimilated to the original relief. The last stage of the process is the revegetation of the area with native species. The project budget is close to 3 million euros and includes specific actions for each of the five areas that the mine waste landfill occupied.
The Terrera Nova was formed in the 1960s with the rejected material from potash mining, composed mainly of sodium chloride (common salt). Between 1990 and 2012, Ercros processed 11 million tons of this salt to use it as raw material in the production of chlorine. With this activity, at the same time as giving value to the waste material, it reduced the salt deposit until its elimination.
The extreme conditions of the released soil -due to saline contamination, the salt crusts on the surface and the high risk of soil erosion- pointed the way to the restoration project.
The salinity was reduced, on the one hand, by removing the salt remains left on the surface of the land after the exploitation and, on the other, by building a drainage network where rainwater ends up. Although the drought of recent years does not help, this is allowing the subsoil to be cleaned.
To recover the morphology of the land, Ercros has had to move more than 180,000 tons of soil and has built terraces in the areas where there were previously terraces. To shape the land, Ercros has valorised surplus topsoil from the construction of the new industrial estate in Cardona.
With the land cleared, the soil free of salt and the ground well settled, Ercros is proceeding to rehabilitate the landscape by revegetating the area. First, however, it was necessary to test in the laboratory the viability of native species that absorb salt and expel it outwards or accumulate it. Now green shoots can be seen on the Cardona landscape.
Today, Ercros consumes more than 300,000 tons of salt per year, which come mainly from Súria. In fact, although it has other suppliers to complete its needs, it consumes all the salt that the Súria plant can supply, thus continuing the environmental task of reducing the salt mine waste landfills in the Bages region.