Remediation strategies for contaminated sediments in The Netherlands
Type:
Presented during:
WODCON XVII: "Dredging in a Sensitive Environment" - 2004, Hamburg, Germany
Authors:
Pieter de Boer, Pol Hakstege
Abstract: Due to water pollution in the past (and to a lesser extent also at present) a substantial part of the sediments in The Netherlands are contaminated. In the last decades the water quality and subsequently the sediment quality has tremendously improved by the reduction of industrial point sources of pollution. Point sources of pollution are since 1970 controlled by means of the Dutch Pollution of Surface Water Acts. In transboundary rivers also international co-operation on point source control has lead to water quality improvement in The Netherlands. The European Water Framework Directive probably will intensify the international cooperation.
As sediments are an essential part of watersystems, the Dutch policy on water management addresses both water and sediments. The Dutch Soil Protection Act became in 1997 relevant to water systems (and of course to the terrestrial environment) because the waterbed is regarded as an "aquatic soil". The Soil Protection Act is divided in a prevention section and a remediation section. Prevention of sediment pollution however, is regulated by means of the Pollution of Surface Waters Act. Therefore especially the remediation section of the Soil Protection Act is relevant to water management. The Soil Protection Act enforces the remediation of contaminated sites.
General goal of remedial actions is to restore a good (in situ) sediment quality to ensure that contaminated sites will not cause risks to humans, ecology, surface-water quality and/or groundwater quality. This general goal is in accordance with the objectives of the European Water Framework Directive (EWFD).
This paper focuses on the strategies and decision making on remediation of in-situ sediments in The Netherlands.
The present situation will be briefly discussed to demonstrate the Dutch approach on remediation and to present the lessons learned.
Keywords: Bioavailability, Sediment Quality Criteria (SQC), Risk Assessment, Ecological effects, Remediation Strategies, European Water Framework Directive