Enhancing communities

Brownfield remediation specialists Bruno Haerens, Cesar Asensio and Ruben Espinosa examine the opportunities for turning former industrial land into thriving urban developments across Europe.

The benefits of bringing brownfield land back into use are clear. As well as removing the risks of contaminated soil and groundwater to human health and the environment, redevelopment brings in revenue from land sales and can help revitalise communities by providing jobs, new homes and green spaces.

Yet, the European Commission estimates that every year more than 1,000 square kilometres of previously undeveloped greenfield land in Europe is appropriated for housing, roads and industry. With more than three million brownfield sites spread across Europe, why are opportunities to reuse these sites being ignored?

Challenges and legacies

For many, the simple answer is that it can present difficulties. After all, brownfields are usually large-scale sites, and clean-up efforts need to be significant and substantial. In the former communist states of eastern Europe, for example, sites tend to be old industrial facilities, with lots of waste inside. A legacy of nationalised industries, their governments may retain liability for cleaning up these sites even after privatisation. Drivers for remediation tend to be around reducing unacceptable risks to health or the environment.

Remediating sites requires considerable up-front investment, often with years before any payoff. With the type and range of contamination varying even across individual sites — ranging from (polyaromatic) hydrocarbons, aromatics, heavy metals to solvents — simply figuring out what needs to be done can take time.

Urban opportunities

Yet there are advantages to working with brownfields. Many of these sites in western Europe are already well connected, with roads and utilities in place. Many more are in desirable locations, near towns and cities, pushing the sale value up. In Malaga, Spain, for example, remediation and redevelopment of an old hydrocarbon storage facility in the centre of the city is transforming a blighted area into a desirable urban zone. While sites east of the old iron curtain may have less surrounding infrastructure, funding for clean-up from agencies like the EU and World Bank is often available, which can offset the cost.

Reducing risks

Adopting a risk-based approach is crucial. While digging out all of the contaminated material may be attractive, it is a relatively crude way to fix the problem — not to mention expensive and disruptive to people living nearby. Instead, assessing the contaminant, its pathways and its receptors, will help create an appropriate and cost-effective solution.

Impact assessments for the surrounding areas are key. For example, if there are heavy metals in the topsoil, where there’s a high risk of it coming into contact with people, extensive excavation may be required. If the contamination is buried further down where there’s a lower risk of human contact, less work may be needed.

Clean up and construct

Integrating the remediation with redevelopment can also help. If a site is being sold for a mixed-use development, there may be different levels of clean-up required for the commercial and residential elements.

Sellers may be able to come to a private agreement with their buyers, whereby the seller remediates to industrial standard, and if the buyer wants to convert to higher standards, such as that required for residential development, they’ll take responsibility for more intensive remediation.

Scheme designers may also be open to tweaking layouts to make remediation more cost effective and sustainable. Placing an underground car park in an area of heavy contamination means that excavation costs can be spread across the remediation and construction phases. Excavated material could also be reused in parts of the site. Infrastructure, such as new roads will not require the soil underneath to be cleaned to the same level as gardens, for example. As well as keeping the cost down, these measures reduce the carbon footprint of the project.

Innovative soil reuse

More than 20 years of industrial activities on a former manufacturing plant in Flanders, Belgium, left several contamination ‘hotspots’ containing volatile organic compounds, hydrocarbons and acids in the soil and groundwater, as well as site-wide soil contamination from heavy metals across six hectares. Working with the developer, the AECOM team integrated excavation and removal of contaminated soil from the hotspots within construction phases using innovative hand-held ‘soil guns’, which use X-ray fluorescence (XRF) spectrometry, to screen the soil. This provided real-time data on the soil composition, identifying how much of it could be excavated and safely reused on site, and which soil needed to be treated off-site before reuse — a time-and cost-effective process compared to waiting for lengthy and expensive lab testing.

Enabling development

Regulation varies across the continent, but in some countries, planning regulations are eased on brownfield developments. The Brownfield Covenant in Flanders, Belgium, provides developers legal, administrative and financial benefits, allowing them to streamline the permitting process and avail of exemptions from financial obligations, such as registration rights or financial warranties.

This was an important factor in delivering the initial phase of a development near Mechelen, Belgium, for example, which was extensively contaminated during nearly 100 years of industrial use.

AECOM worked closely with the regulators to agree appropriate clean-up targets for the land, enabling it to be brought into development under accelerated timescales.

Communities first

Engaging with local communities is also critical. Often this is part of the planning process, but getting the community involved can help ensure a brownfield development is much more than a revenue generator for the developer. Planning regulations may insist that community facilities are part of a new development’s design. Local people can help design these new assets — whether they are parks, playgrounds, healthcare facilities or affordable housing — so that they are in line with the needs of the whole community.

Good for everyone

Land in Europe is a finite resource. While it’s true there are challenges, brownfield redevelopment presents an opportunity for governments, developers and site owners to turn derelict and contaminated sites into cleaner, safer and more desirable places to live and work. It’s a combination of environmental, economic and social benefits difficult to ignore.