COMPOSITION FOR MANUFACTURE OF BARRIER FOR PREVENTION OF DIFFUSION OF CONTAMINANT AND MANUFACTURE OF BARRIER

摘要

PURPOSE: To manufacture a long-life barrier by making it contain soluble basic salt, which buffers an aqueous phase of a composition at a specified pH or above for a specified long period, and activated carbon. CONSTITUTION: A composition contains a basic salt of sufficient concentration to guarantee action, while a pH value of an aqueous phase above 9, during at least about 10 years, desirably for a long period of 50-100 years. An activated carbon may be a well-known type. As a buffering salt, for example, a sodium carbonate or a sodium hydrogencarbonate is used, or sufficient quantity of a quick lime or a hydrated lime to guarantee a buffer effect may be comprised. As weight ratio of the composition, water 1000, cement or binder 402000, clay 25-1000, activated carbon 5-500 and soluble buffering salt, whose pH value is above 9, 30-500 are desirable.