Remediation of Radium from Contaminated Soil.

摘要

The U.S. Environmental Protection Agency is charged by Congress with protecting the Nation's land, air, and water resources. Under a mandate of national environmental laws, the Agency strives to formulate and implement actions leading to a compatible balance between human activities and the ability of natural systems to support and nurture life. To meet this mandate, EPA's research program is providing data and technical support for solving environmental problems today and building a science knowledge base necessary to manage our ecological resources wisely, understand how pollutants affect our health, and prevent or reduce environmental risks in the future. This report presents a discussion of the application of a physico-chemical separation process for the removal of radium from a sample of contaminated soil from the Ottawa site near Chicago. The size/activity distribution analyzed among the particles coarser than 5 micron showed that the activity was uniformly distributed. Almost 50% of the Ra-226 activity was associated with particles of size 5 micron and less. These size fractions are: coarse (+300 micron), medium (300 x 10 micron), and fine (-10 micron). On the basis of the test work conducted in this project, a flowsheet was developed which can be used for on-site demonstration, Figure 38. The report concludes with an outlook of possible future efforts needed in this research area. It is published and made available by EPA's Office of Research and Development to assist the user community.