Fixation and remobilization of trace contaminants in simulated subsurface aquifers

The adsorption and remobilization of radioactive trace elements in porous water-bearing media is of great significance in subsurface waste disposal. Experiments have been done to demonstrate the role of fine particulates and bacteria in the movement and retention of trace contaminants in a model sand bed. Addition of phosphates or complex detergents has been shown to remobilize previously 'fixed' particulates. Organic complexing action, similarly, may be responsible for subsequent movement of originally retained trace materials. (author)