20th September 2006 - A success from start to finish

By Clive Freeman, Contracting Recycling Director, Tarmac Ltd.

Interest in road recycling technology has never been greater and, as the country's leading national road surfacing contractor, Tarmac has been at the forefront of investment in the development of new systems and equipment in this area. Despite this increased interest in all kinds of sustainable development, take-up of road recycling solutions has been slower than might be expected and is only now beginning to gather pace.

While the capability to recover worn out roads and recycle them for use in the construction of new road surfaces has existed for some time, local authorities have been reluctant to be first to implement the new technology. Understandably, there has been some hesitation - few have wanted to apply road recycling technology county-wide or city centre-wide without some assurance that the new solution will provide a high performance and long-lasting solution.

Recognising that clients need an assurance of quality, Tarmac has been working with a number of local authorities to design and implement 'start to finish' road recycling schemes, to demonstrate how the products and processes used comply with the latest quality standards.

While some clients may view these contracts as 'pilot projects', we prefer to view them as schemes for early adopters. By choosing a road recycling solution now, these forward-thinking local authorities stand to gain efficiency and sustainability benefits in the future. But how did we get to this point?

Market takes shape

Since the start of the year Tarmac has significantly extended its road recycling capability. This began with the acquisition of the specialist national road planing business, NRP Ltd, in January and further investment in processing plant and equipment. In particular, Tarmac has recently re-branded its cold lay process, known as Tarmac FoamMaster, for use on road recycling schemes around the country.

We have a great deal of experience in the delivery of major scale road recycling contracts, not least the UK's biggest road recycling scheme completed to date on the A38 in Devon last year. In fact, this contract was a breakthrough for the road recycling industry, demonstrating that sustainable asphalt was viable and practical on a major scale. While the success of this contract undoubtedly helped to encourage take-up of road recycling technology, at the time we were reliant on working in partnership with a small number of specialist contractors to deliver the necessary on-site processing plant and equipment. Now, with a complete road recycling service in place, we are in a position to approach local authorities to see if they would be interested in a ‘start to finish' service.

Other influences have also played a role in the development of the road recycling market. This new start to finish service has come at a time when the Highways Agency and local authorities are focussing more on sustainable development. Driven by Agenda 21, for example, the statutory authorities are increasingly specifying a target level of more than 10% for the use of recycled and secondary materials in suppliers' products.

Coventry takes the lead

One early adopter scheme has recently been completed in partnership with Coventry City Council. Tarmac was contracted to resurface two, 1 km stretches of road in and around the city centre, to demonstrate its new 'start to finish' capability. With a complete road recycling service in place, we began speaking to selected local authorities to see if they would be interested in trialling the service.

The two routes selected for the start to finish challenge were well-used stretches of road, in need of resurfacing. One was at Lentons Lane and the other at Tamworth Road, which provides access to Coventry’s city ring road. These roads were selected partly because while well-used routes, they were not on a main arterial route into the city centre and therefore traffic management issues would be minimal.

Starting on site in June, the contract involved planing the existing road surfaces and re-processing the excavated material using our own on-site plant and equipment to produce around 5000 tonnes of recycled material. This was then mixed to produce a foamed bitumen-based asphalt, called Tarmac FoamMaster, which was then used to construct the lower layers of the new road surface to a depth of about 250 mm in places.

As part of Tarmac’s quality assurance, the recycled mix was tested to ensure that it met the requirement for stiffness and standards specified in TRL 611, 2004, which provides a guide to the use and specification of cold lay recycled materials.

Building on the success of these initial trial schemes, Tarmac has been working in partnership with Coventry City Council to implement further road repair and maintenance work across the city centre, using its complete road recycling solution where possible.

Winning support

Since introducing our start to finish road recycling service earlier this year, we have found that a number of local authorities around the country have been keen to take the lead and develop a more sustainable approach to road repair and maintenance work. In doing so, they have been able to include this sustainable solution within their Local Minerals and Waste Frameworks, demonstrating their commitment to conserving resources and reducing waste. In some cases we have been able to help local authorities to reduce their use of virgin aggregates by more than 10%. This has been achieved by taking a more pan-regional approach, it is easy to see how planings recovered from one road can be re-processed for use in the construction of a new road surface nearby, thus significantly reducing the amount of waste material going to landfill.

Just a few years ago it would have been unthinkable for a quarrying business such as Tarmac to talk about helping local authorities to reduce their use of aggregates and other industrial minerals. Now we have developed our own road recycling solution and we are actively promoting this service. We have all become far more conscious of the importance of minimising waste, conserving valuable virgin materials and making the most of the technological know-how we have gained.

Contract fact file:

- Value: approximately £350,000 for the resurfacing of both stretches of road.
- Location: Lentons Lane and Tamworth Road, Coventry.
- Description of contract: Road resurfacing contract.
- Principal contractor: Tarmac Ltd.
- Start and end dates: May - July 2006
- Quantities of some of the materials used: 5,000 tonnes of Tarmac FoamMaster produced using about 5,000 tonnes of planings removed from the existing road surfaces. Binder and surface courses were also applied.