Hazard Risk Resilience Magazine Volume 1 Issue1 | Page 20

INTRO | HIGHLIGHTS | FEATURES | FOCUS | PERSPECTIVES | BIOS The problem with brownfield Brownfield carries many definitions and associated risks with it. It has been defined as land formerly used by industry that has some level of contamination, preventing it from being developed without meeting environmental and public safety regulatory standards. In the UK, however, it is simply defined as ‘previously developed land’. There is currently no universally agreed definition of brownfield in Europe. The UK currently has a total of around 76,600 hectares of brownfield land (not including Wales and Northern Ireland). In 2003, the Labour government set a target of 60 percent of all new housing to be located on brownfield land. So far the government has identified enough brownfield for 50,000 new homes. Not all of it is contaminated, but many brownfield sites in the UK do have light to heavy levels of contamination, mostly left from industry. In response to this vital problem, scientists and engineers throughout the world are researching ways to restore brownfield land at little economic or environmental cost. hectares (estimated by the EEA) and many others. According to a report released by the Concerted Action on Brownfield and Economic Regeneration Network (CABERNET) in Europe: “Brownfield land will always be with us -- it is a symptom of the process of urban land use change, seen as cities evolve to meet the needs and challenges of a changing society and economy. There will never be, nor should there be, no available brownfield land”. For developing countries such as China, brownfield land is becoming a growing problem. Much of its industrial restructuring has left many abandoned brownfield sites in mostly urban areas. As industrial expansion continues in China, more of its land will be transformed into brownfields in the future. Unless the transfer to industrialisation in China and other developing countries is done sustainably, there will be an even greater need for green, low-cost, methods to regenerate brownfield land. Brownfield density (brownfield area as % of total area of country) There are a variety of mostly expensive hightech methods being explored for remediating contaminated land, but some of the conventional ones are ‘dig and dump’, where contaminated land is moved to a landfill and ‘stabilisation and solidification’, where cement is dug into the ground to immobilise contaminants. Stabilisation and solidification, while much better than the former, has been found unsustainable in many cases and prohibitively expensive for communities who want to regenerate brownfields in their area. There is also the widely used ‘cap and bury’ method where impermeable barriers are created, such as slurry walls, in attempt to seal off contaminants from the rest of the landscape. The problem with moving soil with contaminants is that it doesn’t remediate the problem, but instead moves the source of pollution to a landfill that may even be located near places where people live. Another problem with landfills is that they are subject to the same environmental processes as the rest of the land. Contaminants, such as mercury, lead and arsenic placed in landfills have been known to leach into the groundwater over time threatening human, plant and animal health. The problem of brownfield land is ubiquitous throughout Europe. According to the National Land Use Database, other countries throughout Europe that also have large amounts of brownfield land include: Germany: 128,000 hectares; Poland: 800,000 hectares; France: 200,000 United Kingdom Brownfield Land Profile Estimated total area of brownfield land: ENGLAND: 65,760 hectares SCOTLAND: 10,847 hectares Suspected / potential number of brownfield sites: ENGLAND: 100,000 SCOTLAND: 4,222 Source: National Land Use Database ‘04 Scottish Vacant & Derelict Land Survey ‘04