Towards a better identification of contaminant retention mechanisms in SUDS soil: Zr deficit as a tracer of sediment accumulation

Damien Tedoldi (1) , Kelsey Flanagan (1) , Ghassan Chebbo (1) , Philippe Branchu (2) , Daniel Pierlot (3) , Marie-Christine Gromaire (1)

1 LEESU - laboratoire Eau Environnement et Systèmes Urbains
2 Cerema Equipe-projet TEAM - Centre d'Etudes et d'Expertise sur les Risques, l'Environnement, la Mobilité et l'Aménagement - Equipe-projet TEAM
3 SEPIA Conseils (entreprise)

Among the processes governing contaminant retention in soil-based SUDS, the relative contribution of particle settling and filtration is not always properly identified. Since zirconium is a well-documented invariant in pedology, the present work aimed to assess whether its use might be extended to sediment identification in SUDS. Extensive sampling and analysis were carried out in 11 infiltration systems. Zr contents were found to be significantly lower in road-deposited sediment than in soil. A deficit of this element could also be observed in the most contaminated area of most devices, indicating a "dilution-like" mixture of soil and sediments, the fraction of which could be calculated.

Mots clés: Sediment; Spatial distribution; Sustainable Urban Drainage Systems; X- ray Fluorescence; Contamination; Runoff infiltration

Domaines: Sciences de l'environnement; Ingénierie de l'environnement; Planète et Univers [physics]; Sciences de la Terre; Hydrologie; Sciences de l'environnement

Damien Tedoldi, Kelsey Flanagan, Ghassan Chebbo, Philippe Branchu, Daniel Pierlot, et al.. Towards a better identification of contaminant retention mechanisms in SUDS soil: Zr deficit as a tracer of sediment accumulation. International Conference on Urban Drainage, 2017, Prague, Czech Republic. ⟨hal-01621458⟩