GEOCHEMICAL CHARACTERIZATION OF THE POTENTIAL TRACE-METAL MOBILITY IN COHESIVE SEDIMENTS

The Acid-Producing Potential (APP) and the Acid-Consuming Capacity (ACC) are introduced as basic parameters for long-term pollution assessment of mud disposal. They can be obtained by a four-step sequential leaching technique. The concentration of Ca extracted by the first Na-acetate step permits calculating the ACC. Both the Fe- and S-fractions deliberated by subsequent leaching steps are used to calculate the APP. When the APP of a sample is subtracted from its ACC, a negative value indicates a potential increase of the bioavailability of the toxic metal load upon disposal of this mud in oxic environments.