Innovations - Developers make soil and reduce landfill

Adam Branson, Regeneration & Renewal, 30 May 2008

Paul Mathers: composting can save developers money

By encouraging developers to make their own compost from organic materials already onsite, Wrap hopes to cut down on the amount of materials that end up in landfill sites. Paul Mathers, key account manager for brownfield at Wrap, answers our panel's questions.

Q: Doesn't it slow up a project if people have to make their own compost rather than buying top soil?

A: Not at all. By making the compost onsite or giving advanced notice to a local compost specialist, you have more control over how much soil you get and when you get it. Developers often get stung when they suddenly need lots of top soil and suppliers hold them to ransom over the price.

Q: Isn't all of this an expensive process?

A: Done correctly, composting can save you money. On the projects we've worked on, we've found that we can achieve up to 50 per cent savings compared with buying in top soil. It's essential to the brownfield programme that we can show there is financial as well as environmental value in composting. We know that's the best way to persuade people to change the way they work.

Q: Using compost takes away the need to transport waste to landfill sites, but are there any other environmental benefits?

A: The problem with dumping organic waste in landfill sites isn't just the fact that it needs to be transported there and fresh top soil brought to the brownfield site. If you landfill organic waste, it decomposes differently from when it is composted because it doesn't have any contact with fresh air. The chemicals that are released from that process are more environmentally damaging than those produced by composting.

Q: Is this something that is practical to do on large projects?

A: From a technical point of view, it makes little difference how big the site is. The more organic waste that is produced, the more compost you can make.

Q: If using compost is a better environmental and financial option, then why is top soil still brought in from outside in most cases?

A: People are well aware of the benefits of composting on a local level: they've been composting organic waste to use in their gardens for ages. But it's not well known on an industrial scale. Part of the reason we wanted to do the pilot projects was so that we could go to landscape architects and developers and be able to point to proper case studies. Now that we've got robust figures, making the case should be a lot easier. The Government is committed to progressively reducing the amount of materials that are sent to landfill sites over the next few years, and we think that composting can help it to achieve that.

THE PANEL

Questions were compiled with help from Peter Heath, an associate director at consultancy Atkins, and Graham Duxbury, head of policy and communications at environmental charity Groundwork UK.

Contact us. If you know of an innovative scheme that merits closer scrutiny, email Adam Branson at adam.branson@haymarket.com.