Environmental Risk Assessment of Sediments Deposited in Stormwater Treatment Facilities: Trace Metal Fractionation and Its Implication for Sediment Management

Dissolved metal adsorption capacities and fractionation in filter materials for use in stormwater bioretention facilities

“…4). The high percentages of potentially leachable fractions imply an obvious risk of adsorbed metals being desorbed by changes in the ionic composition of ambient water or development of oxidizing conditions (Tessier et al., 1979), for instance during extended dry periods (which have been shown to affect metal removal in bioretention; Blecken et al., 2009) and/or after maintenance (Karlsson et al., 2016). The latter becomes evident considering that metals primarily accumulate in the top 5 cm of bioretention filter materials (e.g.…”

“…Previous studies have found that percentages of most metals in exchangeable fractions of stormwater sediments (pond sediments, gully pot sediments, road dust etc.) are low or non-detectable (Marsalek and Marsalek, 1997; Karlsson et al., 2016; Jayarathne et al., 2017). However, Jayarathne et al.…”

“…Relatively large amounts of metals may be present in potentially available fractions in analogous materials from other stormwater treatment facilities, e.g. pond sediments (Karlsson et al., 2016). Only one study has addressed such fractionation in bioretention systems.…”

Urban Stormwater Characterization, Control, and Treatment

“…However, the presence of heavy metals in runoff can result in accumulation of metals in these retention structures and potentially the flora which populate them. of Pb were found to be present in mobile forms which represent a greater potential for ecological harm (Karlsson et al, 2016). Two studies were published in 2016 that looked at bioaccumulation in fauna and sediments (Søberg et al, 2016;Stephansen et al, 2016).…”

Discussion of “Wastewater Effect on the Deposition of Cohesive Sediment” by Milad Khastar-Boroujeni, Kazem Esmaili, Hossein Samadi-Boroujeni, and Alinaghi Ziaei

“…However, the most important characteristic of wastewater, i.e., the amount of organic matter, was not reported. It has been shown in numerous papers that the presentation of the results of laboratory analysis of the soil, sediment, or any material added to the soil is necessary because this information makes it easy to interpret the results and understandable for the reader (Mousavi et al 2017b(Mousavi et al , 2018Karlsson et al 2016). On the other hand, the biological properties of wastewater are equally important if not more so because the biological properties of wastewater significantly affect the breakdown and settling of the sediment (Wang et al 2014).…”