Iron mineralogy as a fingerprint of former steelmaking activities in river sediments

Abstract

Submerged sediment cores were collected upstream of a dam in the Orne River, northeastern France. This dam was built in the context of steelmaking to constitute a water reservoir for blast furnace cooling and wet cleaning of furnace smokes. The dam also enhanced sediment deposition in the upstream zone. This study was performed to unravel the contamination status of sediments and to evidence possible contribution sources. The sediment layers were analyzed for water content, grain size, chemical composition, crystalline phases at a bulk scale and poorly crystalline and amorphous phases at a sub-micrometer scale. Visual aspect, texture, color, and chemical and mineralogical analyses showed that the settled sediments were mainly composed of fine black matter, certainly comprising steelmaking by-products. Those materials were highly enriched with Fe, Zn, Pb and other trace metals, except for a relatively thin layer of surficial sediments that had settled more recently. Bulk mineralogy revealed crystalline iron minerals, such as magnetite, goethite, wuestite and pyrite, in the deep layers of the sediment cores. Furthermore, microscopic investigations evidenced the presence of ferrospheres, goethite nanoparticles and newly formed Fe-aluminosilicates; all originating from the former steelmaking facilities. The variation of iron mineralogy, combined with specific chemical profiles and other sediment features, demonstrate the different contributions that constitute the sediment deposit. Furthermore, chemical and mineralogical features of goethite and Fe-aluminosilicates could be used as a fingerprint for such contaminated sediments.

Suspended Materials in River Waters Differentially Enrich Class 1 Integron- and IncP-1 Plasmid-Carrying Bacteria in Sediments

“…The riverbed was strongly modified for industrial purposes. Indeed, two dams were built in the 1958–1965 period and the river was calibrated and channeled in the very last kilometers ( Abuhelou et al, 2017 ; Kanbar et al, 2017 ). Fifteen pairs of river raw water and SM samples were collected along the last 23 km of the Orne River and over an 11-month period from November 2014 to October 2015 (four pairs on 2014/11/04, three pairs on 2015/02/02, two pairs on 2015/02/03, three pairs on 2015/05/05, and three pairs on 2015/10/06).…”

“…Samples were systematically ultrasonicated for 20 s before measurement, and each measurement was duplicated or triplicated. Mineralogy of sediment and SM samples was investigated using X-ray Diffraction and Transmission Electron Microscopy (like in Kanbar et al, 2017 ). A synthesis of those analyses is available in Supplementary Table 1 and Supplementary Figures 2 , 3 .…”

Sediment transport modelling in riverine environments: on the importance of grain-size distribution, sediment density, and suspended sediment concentrations at the upstream boundary

“…In this context, several rivers in north-eastern France were strongly modified (e.g. rectification of riverbeds and dam building) and received high amounts of domestic and industrial effluents linked to steel-making activities located near water sources (Kanbar et al, 2017). As a consequence of these past effluent emissions, riverbed sediments often remain contaminated, although part of the settled material has been dredged and removed (Kanbar et al, 2017).…”

“…rectification of riverbeds and dam building) and received high amounts of domestic and industrial effluents linked to steel-making activities located near water sources (Kanbar et al, 2017). As a consequence of these past effluent emissions, riverbed sediments often remain contaminated, although part of the settled material has been dredged and removed (Kanbar et al, 2017). The remobilization of these riverbed sediments during flood events can subsequently affect water quality and contaminate floodplains (Carter et al, 2006;Hissler and Probst, 2006) and therefore requires thorough investigations (SEDNET, 2003).…”

Sediment transport modelling in riverine environments: on the importance of grain-size distribution, sediment density and boundary conditions

“…dredged and removed from them (Kanbar et al, 2017)., During flood events, the remobilization of these riverbed sediments can strongly impact water and even soil quality (Carter et al, 2006;Hissler and Probst, 2006;Martínez-Carreras et al, 2016).…”