Slag heap. Image credit: Cardiff University

Known for their ability to absorb carbon dioxide (CO2) from the atmosphere, slag heaps (an area, often a hill, made up of refuse from a mine) are being eyed as a possible tool in the fight against global warming.

Dr. Phil Renforth, from the Cardiff University's School of Earth and Ocean Sciences will be leading the investigation into whether or not the sequestration (absorbing CO2) process can be employed to remove harmful greenhouse gases from the atmosphere.

Based on previous research, it is thought that waste material could be used to pull 90 to 155 billion tons of CO2 from the atmosphere over the next century. Dr. Renforth's research will focus on expediting the process all with the goal of reducing CO2 levels in the atmosphere.

Dr Renforth said: “...we will drill into one of these old, historic slag heaps and see what has been happening there over the years and understand what chemical processes have been going on as rainwater has brought carbon dioxide into the heap."