Remediation dredging also requires dedicated equipment which can dredge in a way that recognises the added hazard of working with contaminated sediments. In general, fewer sediment re-handling steps lead to lower implementation risks and lower costs. Efficient coordination of each component is very important for a cost-effective clean-up. Remediation dredging must be conducted in a way that minimises the spread of contaminants to the surrounding waters.

monitoring needs before, during and after the remediation operations.

extent of biological and/or chemical testing and.

physical, chemical and biological characteristics of the sediment.

Prior to the start of the operation, a thorough site investigation should evaluate: The characterisation of material to be dredged is always important, but with contaminated sediment the need is heightened.

disposal (re-use when possible or otherwise confinement).

treatment (pre-treatment, treatment of water and sediment, if necessary), and.

Some of the key components to be evaluated when considering dredging as a clean-up method include: Removal of contaminated sediments from the waterbed is complex and demands thorough, detailed environmental assessments. Ultimately, the aim is to improve overall water quality and restore the health of aquatic ecosystems. Remediation dredging – sometimes called environmental dredging – helps responsible authorities comply with present environmental standards for the removal of dangerous contaminants. Presently national and international governing bodies have strict legislation about contaminants and their disposal, what is permissible and what is not. The whole world has become more environmentally conscious. In the last 25 years, environmental regulations have clearly changed.

Contaminated sediments are often found in industrialised countries, where, historically speaking, few regulations for heavy industries were in place.

What does it mean to dredge a lake