Britpave: The British In-Situ Concrete Paving Association

Soil Stabilisation Could Save England's Ancient Woodland

Click here to visit the LinkedIn Group Britpave Soil Stabilisation / Stabilization Task Group

With housing need and demand outstripping supply, the Environment Secretary Owen Paterson has suggested building on Britain’s ancient woodlands. Rather than concreting over the countryside, the use of cement to remediate brownfield land could help save our ancient woodlands.

Paterson argued that developers could be granted permission to build on ancient woodland if they agree to offset the damage by planting new trees elsewhere. Ancient woodland is classed as areas that have been continuously wooded for over 400 years. A third of woods in England are ancient, covering 350,000 hectares.

“Before building on ancient woodlands the full potential of building on brownfield land should be realised”, said Al McDermid, Chairman of the Britpave Soil Stabilisation Task Group. “According to the Campaign to Protect Rural England, government figures show that the amount of brownfield land becoming available for re-development is far outstripping the rate at which is it being used. There is enough for 1.5 million new homes.”

By its very nature, brownfield land is often more difficult to use than greenfield sites particularly if the site has been contaminated by previous industrial use. The traditional approach to this has been to simply dig up the problem soil and dump it elsewhere. This is not the most sustainable or cost effective approach. “A far better approach is to deal with the problem there-and-then”, explained McDermind. “Insitu remediation and improvement of poor quality brownfield land using cementitious materials to solidify and stabilise the soil removes the cost of lorry movements, landfill taxes and importation of virgin aggregate. It also has a significantly reduced environmental impact.”

Using cementitious binding materials such as cement, lime fly ash or ground granulated blast furnace slag (GGBS) renders potential contaminants immobile and unleachable. Stabilisation of the soil treats the contaminants to produce a soil that is less toxic. Solidification improves the physical properties of the stabilised soil to provide a strong engineered construction material.

“Soil stabilisation/solidification is a most effective way to bring brownfield land back into productive use,” said McDermind. “Of the estimated 61,920ha of brownfield land in England, 54% is derelict or vacant. Soil stabilisation/solidification could help bring this land back into use and so negate the need to dig up our ancient woodlands.”