Innovative technologies along with proven techniques mean fast and efficient on site soil treatment. By Ian Gatenby
A new code of practice – Definition of Waste: Development Industry – from geoenvironmental think tank CL:AIRE (Contaminated Land: Applications in Real Environments) and supported by the Environment Agency, positively encourages developers and contractors to consider site based processes for the re-use of soil that would otherwise be classed as waste.
The economic argument supporting on site treatment of soil is becoming much more compelling. Landfill tax currently stands at £40/tonne and continues to escalate by £8/tonne each year. More significantly, the government has introduced legislation to phase out landfill-tax exemptions; applications for landfill-tax exemption were not accepted after 1 December 2008 and existing exemptions will only be valid until 31 March 2012.
Add to this haulage costs to transport contaminated soil to landfill, often inconveniently located many miles away from a development, along with paying for and transporting natural materials to replace the soil removed, and the figures just don’t stack up.
Think about soil management strategies early on in the development process, for example, as a potential site is being selected or put forward for planning permission, when it is possible to consider whether there is a suitable area for a soil treatment centre. Early involvement in the design process can also ensure that there is sufficient flexibility in the cut and fill strategy for the proposed development to allow soil to be re-used.
The CLUSTER programme, again led by CL:AIRE, enables contaminated materials from a number of developments to be treated at a central, shared hub site. After treatment, some or all of the soil may be suitable for use on either the originating site or on another site within the group.
Above all, we need to consider what soil is worth and not how much it will cost to dispose.
Ian Gatenby is director of Balfour Beatty Geoenvironmental