As a participant in this year’s Environment Analyst Business Summit in the U.K., convening environmental consulting and management professionals from across the region, I wanted to look back on how far we’ve come, both in our thinking about how we view contaminants in our environment and how we tackle the challenges of mitigation and clean up.
How environmental consulting began
Manufacturing processes and the control of waste and emissions have significantly improved since the advent of industrialisation when processes went largely unchecked without much thought given to the impacts on human health or the environment.
It’s been over half a century since Rachel Carson, a prominent nature writer of the 20th century, published her seminal book ‘Silent Spring’ in 1962, documenting the adverse effects on the environment due to the haphazard use of pesticides. Carson challenged the orthodoxy that pollution was an acceptable by-product of development and this thinking became more widespread, eventually informing a shift in discourse and practice.
Even so, for the next decade, much of environmental consulting was limited to academic institutions undertaking post-mortems on the aftermath of private and public entities’ use of chemicals. The U.S. government led in regulatory action, setting up the Environmental Protection Agency in 1970. And the United Kingdom followed with the 1974 Control of Pollution Act, the first comprehensive U.K. legislation that set out what pollution and pollutants were and how they should be managed. With a law in effect, manufacturers had to comply, hence modern-day environmental consulting as we know it began.
As the law developed, so did the consultants, and a patchwork of threshold values were used to classify whether land was contaminated. However, a more thorough approach to clean up had yet to be developed and put into practice, meaning that material was excavated and hauled to landfills in an indiscriminate manner.
Over the past two decades, the manufacturing industry has become more sophisticated, using American expertise to develop risk-based approaches to determine whether there was “significant risk of significant harm,” as required under the U.K. Environment Protection Act 1990. It also became the norm to consider the future use for proposed land that needed remediation. For example, whether the area would be an industrial setting or a public park would determine the level of clean up required.
The source-pathway-receptor model was widely used during this time to govern whether land was deemed to be contaminated. If it was, instead of everything going into a landfill, in-situ techniques were used. We also saw the rise of the industry’s most cost-effective method — monitored natural attenuation, where nothing was added or taken out, and natural processes were left to do the work, with scientists monitoring on a regular basis.
Where we’re headed
Recent reports by the Belgian government predict the whole country will be clean by 2030 as industrial sites are being remediated much faster than new contamination is occurring. However, Belgium is one of the exceptions — and a success story to emulate. With more than a century of pollution caused by industrial activities in other countries, there’s still work to be done. And we do so now with new, innovative approaches and technologies to aid us in this task.
Additionally, we have the opportunity to deal with more complex and heavily contaminated sites that have impacted communities for decades, as well as pollution stemming from the developing world.
Now the consultant’s armoury is tailored to the site. Examples include constructing unseen cement walls in the ground to funnel contaminated water to a treatment zone, or applying electricity to the soil to mobilise contaminants, or using telemetry for constant monitoring of important parameters. As well as enhancing the technical solutions, consultants have become more aware of other impacts, such as the carbon footprint and effects on communities, which help determine what techniques to use.
Finally, the contaminants we must deal with have changed. Previously, oil, asbestos, coolant fluids and heavy metals were the primary concern. Today, perfluorinated chemicals are the top priority, specifically poly and per fluoroalkylated substances (PFASs). These chemicals have been used in various industries, from waterproof clothing and photography to firefighting foams and fast-food packaging. They’re extremely heat stable, resistant to breakdown and potentially toxic to humans. Thus governments around the world, using the precautionary principle, where it’s better to be safe than take the risk of harm, are now insisting on remediation of PFASs.
The stability of PFASs and their very low levels of acceptability make detection and remediation difficult. To tackle this challenge, AECOM is working at the cutting edge of research developing new methods to actively destroy these compounds, with one technology in particular showing promising signs of achieving this goal (DE-FLUOROTM).
Over time, our knowledge and understanding of contaminants has improved considerably, and we’ve reached a stage where we’re much better able to mitigate the impacts or prevent them in the first place due to the development of new methods and technologies.
Today, best practice for industrial companies involves devising tailored solutions that address the individual circumstances of a remediation effort. The vocabulary has changed from “dig it up and dump it in a landfill” to “we need a sustainable, flexible, robust and cost-effective solution.”