Polluted sites and soils

The European Commission surveyed European citizens on the problems related to soil degradation. Two questionnaires were made available, one for citizens and one for organisations (specialised and/or public and private organisations). The replies received ?{ 1,206 for “citizens” and 662 for “organisations” ?{ clearly show that the leading concern of Europeans is soil contamination. As for the other threats, citizens and organisations had differing points of view. For example, biodiversity loss was the second most serious threat for citizens, while organisations ranked it only fifth.

Turnover in the rehabilitation of polluted sites and soils market was 340 million euros in 2003 (turnover for the sector – BIPE forecasts).
The market grew steadily from 1992 to 2000, but saw some variations in annual growth, particularly between 1995 and 1996 when it remained relatively stagnant.

Contractors, site cleanup professionals, enter into contracts for cleanup operations for :

• Sites that pose a threat to human health and the environment,
• Real estate construction or service projects (such as the Stade de France),
• Business stoppage,
• Business transfers, accidents.

Carbon is an essential component of soil organic matter which in turn plays an important role in the global carbon cycle. Research shows that some 1,500 to 2,000 gigatons (Gt) of carbon are trapped (enclosed) in soil organic matter each year. This quantity can be related to the 750 Gt of anthropogenic carbon emitted into the atmosphere each year, which highlights the importance of soil organic matter in relation to climate change. There is, however, a limit to the amount of organic matter, and therefore carbon, that can be stored in soils. Moreover, maintaining or increasing soil organic matter content requires particularly attentive management.

In France, the joint scientific study conducted by INRA (2002) showed that, for the 0 to 30 cm layer, the overall carbon stock of soils in France can be estimated at no less than 3.1 million tons. These stocks vary greatly depending on the region and soil use and management (e.g. estimates are very low in very intensive farming areas, moderately high in forest or forage regions and very high in mountainous areas). The maximum additional storage capacity of carbon in the soil could be around 1 to 3 million tons per year.

From : Sols et environment. Cours, exercices et études de cas. Under the supervision of Michel-Claude Girard, Christian Walter, Jean-Claude Rémy, Jacques Berthelin, Jean-Louis Morel. Dunod. Collection Sciences Sup - 832 pages - 2005. ISBN: 2100055208.

The Réseau de Mesure de la Qualité des Sols (French soil quality monitoring network - RMQS) monitors 16km square grid cells in 2,180 sites spread out evenly across France based on the European Network for Forest Damage Monitoring. A total of 1,640 sites are therefore being added to the 540 sites of the pre-existing forest network. Measurements and observations will be noted on a regular basis at each grid cell’s centre. This configuration was chosen to cover most of the soil-occupancy combinations in France and to optimise costs. The network was officially launched in the spring of 2000, since which time more than 750 sites have been set up. Thanks to this network, it is already possible to map soil quality and show gradients (particularly those related to large-area pollution).

Large-area soil contamination generated by human activities comes from a variety of sources. According to estimates made in 1998, the amounts of Cu, Zn, Cd and Pb were 5,300, 3,200, 68 and 8,300 tons per year, respectively. The following graph shows the respective contributions of the various sources. The figure for Pb must undoubtedly be reviewed since lead has, for the most part, been eliminated. These data are in the process of being updated.

Relative contribution of various sources to agricultural soil contamination according to "Soil Contamination by Rare Elements: Risk Management" - Report published by the French Academy of Sciences No. 42, August 1998. Coordinators: P-H. Bourrelier and J. Berthelin.

Measures aimed at soil protection and management first require in-depth knowledge of the methods used to sample and characterise the soils (physiochemical and biological parameters), along with a definition of appropriate, standardised terminology. This information is essential to all those wishing to assess and manage soil quality. Standardising the vocabulary and methods allows all stakeholders to understand each other and to accept and interpret the results of the measurements on the same basis. More than 150 standards exist in the area of soil quality.