A potential source of recycled aggregates?

England’s World War II airfields still have a lot to offer. Some have been redeveloped for industrial uses and, for many sites, their historical importance has been recognized and retained.

They can also be a valuable source of materials, however, and WRAP (the Waste & Resources Action Programme) last year commissioned TRL to assess their potential to be used as a source of aggregate in England.

A typical runway may contain around 64,800 tonnes of concrete and as there are at least two runways at any site, plus taxiing and parking areas, a single airfield can contain a significant quantity of recyclable aggregate.

TRL determined the location and status of all airfields in England, to establish those with the potential to provide recycled aggregates. Information on the primary reserves of crushed rock available in all regions across England was also assessed. Many counties to the north of London and in eastern England have disused airfields with high potential for recycled concrete, while having few primary reserves of crushed rock. These areas are also scheduled for major development.

The potential quantity of concrete available has been estimated at 9.5 million tonnes, of which 5 million tonnes could arise from just five large airfields. One million tonnes of asphalt planings may also be available. Although there is this quantity of recycled material potentially available, it is still possible that the most sustainable option for these sites will be reuse rather than recycling and any developments at the identified airfields are likely to be over the medium to long term.