Recycling tar planings
Tar was used as a binder in UK roads until the 1980s, and when roads are renovated it is usually regarded as a hazardous waste for disposal. Tarmac National Contracting came up with an innovative solution to recycling tar planings, helping local authorities to cut waste to landfill, disposal costs and carbon emissions. Working together in the Gloucestershire Highways Partnership with Gloucestershire County Council and Atkins, we found a new way to convert tar-bound planings into a usable and safe road construction material.
While conventional road planings are regularly recycled, the challenges of recycling tar-bound road planings safely mean that the material has traditionally been sent to landfill. Drawing on their combined expertise, the team developed a new cold mix material containing tar planings. The material can be stored for up to three weeks and can be used to repair defects on lightly trafficked road networks.
Technical manager at Tarmac National Contracting, Neil Thomas, said: “As no one in the UK had used this material before, we carried out extensive tests and showed the Environment Agency that the technique was safe. We closely monitored test sites to check for failures such as cracking or rutting, while coring and testing was also done periodically from the materials laid.”
Other companies and authorities are now adopting the technology. Gloucestershire County Council asset manager, Scott Tompkins, said: “Developing this new cold mix material means we reuse 8,000 tonnes a year of tar-bound material. This saves Gloucestershire Highways around £1 million a year in disposal and transportation costs and avoids around 325 tonnes of carbon emissions.”