Soil quality

As the interface between earth, air and water, and home to most of the biosphere, soil plays a key role in the carbon cycle and other chemical elements essential to life, and can therefore have a significant impact on climate change. Soil is a source of food, biomass and raw materials; it serves as a platform for human activities, is a landscape and heritage element, and plays a central role as a habitat and genetic reservoir. This essential, extremely complex and largely non-renewable natural resource is nevertheless being increasingly damaged by certain human practices. Soil protection is therefore of vital strategic and economic importance on a global scale.

This awareness is relatively recent, and means that soil protection must include an important dimension of managing the legacy of the industrial past (mining, iron and steel, metallurgy, etc.).

In its Déclaration de Politique Régionale (DPR), in line with the Marshall Plan 2.vert, Wallonia places particular emphasis on the continued rehabilitation of polluted sites, with a view to protecting the environment, improving Wallonia’s image and ensuring integrated, sustainable land management as part of its spatial planning policy.

ISSeP currently supports various government departments in soil and subsoil management.
These missions are based on ISSeP’s in-house expertise in two specific areas:
– The laboratory: analysis of potentially polluted matrices (soil, water, air);
– Expertise: field services (measurements and sampling), interpretative studies, risk studies and validation of these achievements.


Environmental studies on hazardous sites

For SPW Territoire, Logement, Patrimoine, Energie, and more specifically the Direction de l’Aménagement Opérationnel et de la Ville (DAOV), ISSeP assesses the environmental situation of disused industrial sites (SAR, SRPE) on the basis of historical surveys, usually carried out by ULg’s Centre d’Histoire et des Techniques (CHST). The Institute carries out soil surveys on these sites to monitor pollution levels. In some cases, these initial investigation phases are followed by more comprehensive studies (characterization, risks) proposing an optimal rehabilitation strategy, taking into account the site’s development project, when the operator has a preliminary design. This makes it possible, where appropriate, to guide the development project in the best possible way, taking into account the environmental situation of the site under study.
ISSeP also provides technical support to DGO4 during the rehabilitation of these brownfield sites.

Technical support for the Soil and Waste Department

As part of its mission to support the Soil and Waste Department (DSD) of SPW Agriculture, Natural Resources and Environment, ISSeP provides technical advice on studies carried out by accredited experts. These opinions concern the investigations carried out and the expert’s interpretation of the results, as well as any risk modelling. The Administration’s requests may concern any stage of the procedure: Orientation Study, Characterization Study, Sanitation Project, Final Inventory. These notices are intended for the DSD (Direction de la Protection des Sols – DPS or Direction de l’Assainissement des Sols – DAS), so that the agents in charge can have the information they need to examine the dossiers.
These requests may also concern the drafting of specific protocols, when the Administration deems it necessary.

Walloon Code of Good Practice CWBP

As part of the implementation of the “Soil” Decree, ISSeP played an active role in drawing up the Walloon Code of Good Practice (CWBP) by drafting and revising the Reference Guides for Orientation Studies (GREO), Characterization Studies (GREC), the Remediation Project (GRPA), the Final Evaluation (GREF) and by revising the Reference Guide for Risk Studies (GRER).
Both the Compendium Wallon des méthodes d’Echantillonnage et d’Analyse – CWEA and the CWBP are evolving documents. The administration plans to publish vintages of these books, to correct any shortcomings in the methodologies described, and to amend them with new protocols.
In addition, training courses for accredited experts are also planned to explain the different methodologies and directions taken by the guides. ISSeP provides technical support to the Administration in updating and organizing training courses.

Land Management Reference Guide GRGT

As provided for in the AGW “Terres”, the ISSeP, in collaboration with the Administration and stakeholders in the field, has drawn up the Guide de Référence pour la Gestion des Terres (GRGT). This Guide is intended to complement the Order in terms of practical and scientific aspects, and aims to guarantee the quality of the appraisal process, as well as to support all stakeholders in the quality control and traceability of soil.

Soil quality correspondent: Robin Lambotte – 04 229 83 59



  • Walloon Government Decree of March 1, 2018 on soil management – “Soil” Decree

Excavated soil management

  • Walloon Government Decree of June 14, 2001 promoting the recovery of certain wastes
  • Order of the Walloon Government amending the Order of the Walloon Government of July 10, 1997 establishing a waste catalog.
  • Order of the Walloon Government prohibiting the placing of certain waste in technical landfill centers (and setting the criteria for the admission of waste to technical landfill centers (modified by AGW of 11/07/2013).
  • Order of the Walloon Government of July 5, 2018 on the management and traceability of land – AGW “Land”.


Sampling (link to the Field Activities and Measurements Department)

Testing (link to the Analytical Laboratories Department)

Partners and useful links


  • DGO3, Direction Générale opérationnelle de l’Agriculture, des Ressources naturelles et de l’Environnement (activate link to website)
  • DGO4, Direction générale opérationnelle – Aménagement du territoire, Logement, Patrimoine et Energie (link to website to be activated)
  • Université de Liège, Centre d’Histoire des Sciences et des Techniques, Département des Sites industriels désaffectés (activate link to website)
  • SPAQuE, Société Publique d’Aide à la Qualité de l’Environnement (link to website)

Useful links

Walloon Compendium of sampling and analysis methods – CWEA
CWEA – Scope of application

Code de l’Environnement (Livre I et Livre II) – Coordinated version