Volcanic rock and sedimentary rock often contain heavy metal. Heavy metal gives bad influence to health of human body. In general, excavation gravel containing heavy metal is processed by interception using sheet. But durability of sheet is not eternity. We examined chemical tecnique by rock or clay replacing with sheet. Some materials such as sandstone or kaolin clay reduce quantity of dissolution of heavy metal from excavation gravel. In the future, it is important to use materials of nature in order to intercept the diffusion of heavy metal.