Industrialization, mining activity, urban densification, agriculture intensification, and war have contributed to soil contamination. This pollution is said to be responsible for some 500,000 deaths worldwide in 20151, due to chemicals and pathogens transmitted to humans through direct contact (skin exposure or inhalation of polluted soil particles) or the consumption of food and water having accumulated large amounts of pollutants from soil.
An overview of soils
According to FAO, at present “about 33% of all soils are degraded, and the state of soils is deteriorating at an alarming rate.” For example, Australia counts almost 80,000 polluted sites, while there are three million in the European Union plus the Western Balkans. In the United States, at least 1,300 sites appear on the list of polluted spots identified as a national priority. Last but not least, China recognizes that 16% of all its soils are polluted. This worrying inventory also includes numerous derelict sites (mines, industries, military bases): 450,000 in the United States, 200,000 in Canada, 300,000 in the United Kingdom, and 400,000 in France2. In other words, hundreds of hectares that could be treated and restored, then reused for agricultural, real estate, or other purposes. However, despite these identification efforts to estimate the scale of the phenomenon, the absence of a global assessment represents an obstacle to harnessing the necessary economic resources and powerfully engaging public and private players in this fight.
Urgent action is required worldwide to tackle this pollution and the many threats that it poses to food security and public health.
A global resolution, national strategies
During the third session of the UN Environment Assembly (UNEA3) in 2017, the member countries adopted a resolution calling for faster action and collaboration to treat and manage soil pollution: measures must be taken on a national and regional level to understand the extent of soil pollution in their countries and strengthen policies aiming to prevent, reduce and manage soil pollution. In this respect, research to develop new scientific decontamination methods is continuing. Increasingly expensive physical decontamination techniques, such as inactivation or the sequestration of chemicals in landfills, have been replaced by biological methods, such as microbial degradation and phytoremediation. Maintaining soil health and preventing and reducing soil pollution is achieved by promoting ecologically reasonable management practices and environmentally friendly industrial processes, reducing waste production, recycling and reusing products and materials, and sustainably storing waste.
A combination of skillfully mastered expertise
In this international context, Veolia — a world leader in water, waste and energy — is bringing its expertise to bear on soil decontamination with a broad array of (chemical, thermal or biological) treatment technologies. The choice of one in particular or a combination depends on multiple criteria: the level of reduction and/or stabilization required (according to future use), the type of pollutant concerned, the time available, the environment of the site, the volume to be treated, and finally the cost.
“Soil remediation is an expertise that Veolia has already been developing for a long time through its different subsidiaries: Sarpi with GRS Valtech and Sede,” explains Cédric L’Elchat, CEO of Sarp Industries, a Veolia subsidiary.
“Depending on the case, we can treat both soils and phreatic groundwater. Each situation requires one or more specific techniques, as sites polluted with explosives, chemicals, heavy metals and hydrocarbons are treated differently. The solutions chosen may be in situ, where the soil is treated on the spot with treatment methods using heating tips or intrusive techniques. Depending on the need, we use thermal desorption3, chemical or biological soil treatment. However, the solutions may also be ex situ, such as excavating soil and transporting it to dedicated centers in Veolia’s channels.” Jean-Christophe Taret, Senior Vice-President, Strategy, believes that this could become a rapidly expanding market:
“The vast majority of our activities are based in France, pending our next development in China, a part of the world so concerned by this issue that the government has put in place strong legislation on the treatment of soils to make them fit for industrial, agricultural or urban use.”
Exploring the field of the possible
To complement the arsenal of traditional technologies at its disposal, Veolia is exploring a whole field of innovations, which are all the more promising as they are more natural, resource-efficient and inexpensive. The Group is taking a particular interest in treatments using phytoremediation4 and microbacteria5, which are currently at the R&D phase. Both are transpositions of know-how and technologies that already exist at Veolia to treat water. “With phytoremediation,” explains Jean-Christophe Taret, “we are breaking away from chemical treatment, but we still have to find a way to treat the plants in turn, once the post-remediation work has been done. As they are loaded with metals, they must be incinerated to prevent them from contaminating the environment again. The same applies to biological treatments: it’s a matter of identifying the right bacteria, making them proliferate so that they become more insatiable and absorb more pollution and, finally, knowing how to treat bacterial residue.” As soon as they are able to treat heavy metals and compounds such as PCBs (polychlorinated biphenyls), these solutions may be applied to all kinds of soil uses: urban planning, industry and agriculture.
Changing the scale of regulatory standards
The international roll-out of standards and methods for diagnosing or characterizing polluted soils and sites is a key challenge to be met by Veolia. “The parameters to be analyzed in soil treatment, identifying the nature or source of the pollution, how the pollution is spreading in the soil, and the impact on the population and biodiversity are all complex data that require a standard methodology across the board,” argues Jean-Christophe Taret. “Starting with the countries most concerned — the United States and Europe — in other words, the most industrialized.” This point of view is shared by Jean-François Nogrette, Senior Vice-President of Veolia Technologies & Contracting and CEO of Veolia Water Technologies, who underlines the importance of a widespread regulatory framework to ensure the traceability of the treated soil: “There is an important need for regulation applicable on a wide scale and, without a doubt, the water sector will be the one to trigger a stricter view of Environmental law.” With a soil remediation methodology in place since 2017, France is leading the way in this area. And other countries are tackling the issue, including China, which has already enacted a number of laws.
Prevention rather than cure
As is true of many sectors, it is much more expensive to repair damage than prevent it. For this reason, one of the developments on the site and soil remediation market will be supporting companies and local authorities upstream in anticipating pollution risks. This approach will be reinforced by the introduction of preventive regulations, along with increasing pressure due to citizens’ growing environmental awareness — which garners broad media and social media coverage — and CSR policies, which have become a must.
This heightened preventive role already preempted by Veolia could also be facilitated by technological progress. “Our ace card on this market is access to polluted water and phreatic groundwater. By combining our soil and water treatment technologies and expertise, and drawing on digital tools, we are going to upskill to model the condition of soils, control the spread of pollution in phreatic groundwater, etc.,” envisages Jean-Christophe Taret. “We will have all the data to anticipate health crisis risks linked to soil pollution and implement appropriate solutions.” For Veolia’s Senior Vice-President, Strategy, “in the years to come, prevention will become a major issue at stake, along with the question of having to feed a constantly growing population.”
Kindling a promising market
With its 2.7 billion euros, the soil remediation market is still in its infancy.
However, “in the context of a growing global — and especially urban — population, the need for available land areas will also increase,” explains Jean-Francois Nogrette.
Veolia must therefore be able to provide solutions that are entirely acceptable from an environmental and health point of view, regardless of the problem or the client in question. In order to have the right to carry out their activities, industry must take this issue into account, prevent the risk, and be able to handle it if it arises. In order to develop, cities must offer land that can be used. While farmers must be able to work on the healthiest possible soils. “Under combined pressure from the public authorities (regulations) and private players (particularly industry), we should expect the market to double in size over the next twenty years,” predicts Jean-Christophe Taret.
- The Lancet, October 2017 $
- L’Usine Nouvelle “Dépolluer les sols, un travail de fourmi,” April 2018
- This decontamination method, well suited to both light and heavy hydrocarbons, consists in heating land to between 400 and 600°C so that pollutants are volatilized. The dust is removed from the gases emitted and they are purified by a bag filter.
- Plants absorb pollutants from soil, especially metals (nickel, arsenic, lead)
- Microbacteria feed on pollution (e.g. PCBs, among other powerful pollutants) and accelerate its breakdown