Abstract
Abstract
At present in Japan industrial wastes are disposed in accordance with Waste Disposal and Public Cleansing Law.
For sludge produced through waste treatment process it is tested by the stipulated method to detect any hazardous substances in it, and the sludge judged to contain such substances must be disposed in a mandatory way. But in reality most of wastes are judged not to contain hazardous substances and are disposed by an ordinary reclamation method. There is no denying the possibility, however, that wastes thus disposed will threaten to pollute the environment in the future.
In this view the authors conducted several heavy metals extraction test of wastes treatment sludge. The results showed that, some of heavy metals was extracted in the experiment using the drainage taken from Inside-Central-Breakwater Waste Disposal Site, although very little of them was extracted by the stipulated method.
These findings seem to suggest that a large amount of sludge which is now being disposed ordinarily be disposed in an isolation reclamation way, and that the stipulated Criteria to judge “hazardous” be made as severe as the Effluent Standard Levels.
