Sediment characterization during oxidation and ripening and evaluation of its potential reuse

The environmental impact and possibilities for remediation and reuse of contaminated sediments was investigated. Water-soluble and (NH4)2-EDTA-soluble metal concentrations in sediments from three different rivers were monitored for five months after dredging. Furthermore, the pH-dependent leaching behaviour of heavy metals and the influence of elevated temperatures (900-1100 degrees C) on the release of metals were investigated in order to evaluate possibilities for remediation, through thermal treatment, and reuse of the sediments, such as for the production of bricks and lightweight aggregates. In general, the sediments investigated in this study present a relatively low risk to the environment when exposed to upland conditions. If the sediments were to be used for the production of bricks or lightweight aggregates, the increased mobility of As, Cr and V following thermal treatment of the sediments should be taken into account.