A family from Toowoomba, Australia, has worked eight years to develop a concrete mix that doesn't include portland cement. The recipe, which they now plan to export to regions such as the Middle East and other markets that have corrosive soils, has been used in portions of precast tunnels in Malaysia and Qatar. The Earth Friendly Concrete incorporates slag and fly ash reclaimed from steel manufacturing operations and coal-fired power stations. One of the most visible uses of the concrete is found in a Brisbane airport's aprons and taxiway pavements.