Amsterdam-based architect Angelo Renna has proposed a 90m-high "sponge mountain" to absorb air pollution in Turin, an industrial city with one of the highest levels of particles in Europe.
The idea is to heap up 6 million tonnes of sand and soil excavated from the construction of a 57km railway tunnel, part of the project to build a high-speed rail link between Turin and Lyon. This would then absorb carbon and pollutants from the air.
The project is being supported by the Success Project, a multidisciplinary body based at Newcastle University that has been researching the use of urban soil to capture carbon and support ecosystems. It says quarry soil has the best capacity to absorb carbon dioxide.
The mountain is not the first idea for reusing spoil created during construction. Earlier this year, Elon Musk’s Boring Group announced that it was planning to sell "Lego-like interlocking bricks" made from tunneling waste that could be used to create sculptures and buildings.
Images courtesy of AngeloRenna/Success