A concept to minimize the negative effect of heavy metal leaching on geo-environment from bottom sediments due to dredging/reclamation works is discussed, based on the experimentally evaluated leaching characteristics of Zn from the clay slurry. Batch leadcing tests are conducted on Fukakusa Clay (LL = 47.4percent, PL = 26.0percent, CEC = 23.6 meq/100g) suspension doped with Zn (Zn(NO_3)_2 6H_2O) as an index heavy metal. Also, the consolidation leaching test is proposed to examine the leaching mechanism in the dehydration process. These experimental results show that (1) the relationship between Zn adsorption per 1 g soil and equilibrated concentration of clay suspension varies with extracting volume ratios (L/S), (2) Zn adsorption per 1 g soil is depndent on the doped mass of Zn per 1 g soil regardless of L/S, and (3) consolidation has no effect on the leachign of Zn. Based on the above results, leaching mass of heavy metals associated with dredgign, dehydration, and reclamation is prametrically predicted to assess the effects of water contents before/after dredgign and dehydration.
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