Approaches and Frameworks for Managing Contaminated Sediments - A European Perspective

Abstract

Sediment is an essential, integral and dynamic part of the hydrologic system. In natural and agricultural basins, sediment is derived from the weathering and erosion of minerals, organic material and soils in upstream areas and from the erosion of river banks and other in-stream sources. As surface-water flow rates decline in lowland areas, transported sediment settles along the river bed and banks by sedimentation. However, because sediments are the ultimate reservoir for the numerous potential chemical and biological contaminants that may be contained in effluents originating from urban, agricultural, and industrial lands and recreational activities, contaminated sediments in rivers and streams, lakes, coastal harbors, and estuaries have the potential to pose ecological and human health risks. The management of sediment quality and quantity in support of ecological and socioeconomic goals is a cause of extensive research, investment and regulatory and public scrutiny, both in Europe and internationally. This chapter examines the management of sediment from a European perspective. The first section discusses the role of sediment management in achieving European ecosystem objectives. Section two summarizes the findings of the EC-funded, demand driven European Sediment Research Network (SedNet). Section three describes a framework risk assessment and management in a major European region, the Venice Lagoon. The next three sections describe aspects of sediment management in an EC accession country, and the host country for this workshop - Slovakia. Section four describes river and lake sediment contamination and related legislation in Slovakia. Section five discusses the assessment and management of Persistent Organic Pollutants (POPs), a major risk driver in Slovakia. Section six discusses a specific class of POPs - PCBS in sediments of a specific region of Slovakia. Finally, Section seven discusses some barriers to successful sediment risk assessment and management, and lists science and infrastructure needs to address these barriers. Whilst all the authors of this chapter are living and/or working in Europe, and the focus is on European perspectives, much work has benefited from international collaborations and we feel that many of the observations and recommendations will have relevance to a broader audience

Restoring Soil Quality to Mitigate Soil Degradation

“…While integrated water management alone is useful [64], the importance of the soil-water nexus cannot be over-emphasized [24]. Management of sediments, especially contaminated ones [65], is another important component of the soil-water nexus that must be critically examined.…”

Is risk-based, sustainable sediment management consistent with European policy?

“…Depending upon the stakeholder, the role of sediment can range from a potential contaminant and/or siltation nuisance to a fundamental natural substrate, providing critical ecosystem services. This variation in viewpoint may, in part, result from the current regulatory situation in Europe, in which sediment management is explicitly or implicitly included in various regulatory contexts, but not specifically on its own (Casper 2008), and in part, because sediment, as a dynamic component in the hydrological cycle, moves throughout environments and thus links various sectoral issues (Apitz 2005(Apitz , 2006Apitz et al 2006a). Unfortunately, this means that across Europe, with the exception of management of dredged material, the level of consideration afforded to sediment management has thus far been primarily left to the discretion of individual countries and agencies (Bridges et al 2006) (Casper 2008).…”

Sustainable Use of Reservoir Sediment through Partial Application in Building Material

“…In natural and agricultural basins, sediment is derived from weathering and erosion of minerals, organic material and soils in upstream areas and from erosion of river banks and other in-stream sources [1]. The sedimentation of reservoirs over multiple years causes large capacity losses of the reservoirs.…”

“…However, the favorite dredged material management options are natural options and beneficial re-use is a way to encourage the use of dredged material as a potential resource and not as a waste [18]. Management options for the dredged material depending on its physical and chemical characteristics [19][20][21] are sediment relocation and the use of dredged material as substrate for soil amendments to enhance agriculture [22] or retaining sediment within the natural sediment system to support sediment-based habitats [1,23]. With the shortage in some regions of the world of natural resources in many engineering fields, the beneficial reuse of sediments as a construction material [19,24] can optimize the management of the natural resources [25].…”