Recycling disused airfields in the UK could potentially yield 9.5 million tonnes of concrete plus one million tonnes of asphalt planings.
Research funded by the Waste and Resources Action Programme (WRAP) and carried out by C4S ascertained that there are 688 inactive airfields in England; however, not all are suitable for recycling.
While some have been used as industrial parks, residential developments or leisure facilities, the study found that although using such resources for aggregates may not get off the ground nationally, the idea may fly if applied locally.
The findings are particularly pertinent to the east of England, which will require considerable aggregates resources for the construction of housing, roads and community facilities.
With the four major growth areas- Thames Gateway, Milton Keynes and south midlands, Stansted and Ashford in Kent- having the least permitted reserves of crushed rock, it is a positive coincidence that the majority of airfields identified are located nearby.
WRAP technical advisor to the Aggregates Programme John Barritt said: Reserves of crushed rock in England vary from region to region and this often necessitates the transport of rock to areas where development is planned, but natural resources are low.
As airfields are dispersed across England, there is an opportunity to recycle the concrete asphalt runways to provide recycled aggregates in regions with limited reserves. WRAP funded the research to see just how practical it would be in reality, and if the quantities available were significant in the context of total aggregate demand.
Of the estimated 9.5 million tonnes available from such sites nationally, around half would come from five large airfields in the east of England.
With a single runway of 2,000 metres generally containing around 64,800 tonnes of potentially reusable material, the research concludes that disused airfields could represent an economic alternative to imported crushed rock at a local level.
While planning consent may be an issue on grounds of noise and dust and the quantities are not significant in terms of national and regional planning, the four major growth areas could reap considerable benefits.