Sediment contamination is a major environmental issue due its potential toxic effects on biotic resources and human health. A large variety of contaminants from industrial, urban, and marine activities are associated with sediment contamination. These include: heavy metals, persistent organic pollutants, and radionuclides among others.
Contaminants such as heavy metals and persistent organic pollutants are accumulated overtime forming secondary reservoirs. These contaminants can:
- Be released to water, thus migrating to other sediments or absorbed by biota
- Accumulate in aquatic organisms and move up the food chain to fish and eventually humans.
High human pressure on water systems calls for increased dredging in:
- Maintenance works (depth for shipping and drainage)
- Construction works (flood defence, recreation, harbour enlargement)
- Supply of construction material (sand, gravels)
- Remediation works (hot spots)
This can potentially redistribute the contaminants to water, landfills, and construction materials.
European Union legislations of relevance for sediment management are:
- European Landfill Directive
- European waste legislation
- Water Framework Directive 2000/60/EC and its amendments
Several national and international Conventions deal with the quality of sediments and dredged materials:
- The Helsinki Convention on the Protection of the Marine Environment of the Baltic Sea Area: HELCOM recommendation Disposal of dredged spoils (1992).
- The London Convention on the Prevention of Marine Pollution by Dumping of Wastes and Other Matter. Dredged Material assessment Framework (2000).
- The Convention on the Protection of the Marine Environment of the North-East Atlantic (OSPAR): Revised guidelines for the management of dredged material (2004).
Due to implementation of international conventions and EU Directives, the different national authorities have developed specific dredged material guidelines and/or specific legislation on sediments. ALS Environmental has developed numerous sediment programs for the assessment of contaminated sediments, which fulfil the most stringent classification of materials.
Our portfolio for sediment contains, but is not limited to, the following compounds/tests:
- Dry matter
- Basic granulometry
- Full grain size
- Heavy metals (mercury, lead, nickel, zinc, copper, cadmium, etc.)
- Metal speciation (methylmercury, arsenic compounds, selenium compounds)
- Tributyltin (TBT) and other organotin compounds
- Total petroleum hydrocarbons (TPH)
- Radionuclides, including alpha and beta activity
- Octylphenols, nonylphenols and their ethoxylates
- PCBs, PAH, hexachlorobenzene
- DDT and isomers, lindane, chlorobenzenes
- Polybrominated diphenyl ethers
- Dioxins and furans
- Ecotoxicological tests on aquatic organisms (plants and animals)
- Microtox (Vibrio fischeri)
Project specific quotations are strongly recommended for sediment work. These quotations will clearly specify limits of quantification, compounds configuration, sample containers and sample volumes, and provide details on logistics. For further details contact your local ALS representative.