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	Phytoremediation of Radionuclides
	Traditional Methods for Cleanup of Radionuclides
Home Overview of Radionuclides Traditional Methods Plant Species Soil Phyto-remediation Rhizofiltration Disposal References
		The traditional methods for remediation of radioactive contamination involve the removal and off-site minimization of the material or in-situ methods that stabilize, vitrify, or solidify the radionuclides within the soil matrix. Cleanup methods should be directed by the health risks of the contamination, future land use goals, economics, and the feasibility of achieving the stated goals of the remediation. Excavation of soils with unacceptable levels of radionuclides is a common activity, although it can be expensive and movement of the material has inherent risks, including the dispersal of soil material via wind or erosional processes during the excavation and transportation to an off-site facility. Once the material is removed, several processes are available to segregate highly contaminated soils and minimize the contamination prior to disposal in an appropriate facility, usually a low-level waste (LLW) depository for radioactive material. Common methods to segregate and minimize waste include: detector based segregation, soil washing by particle separation, soil washing by chemical leaching and extraction, flocculation, reverse osmosis ultra-filtration and electroremediation (Negri and Hinchman 2000, Pearl 2000).



			http://www.frtr.gov/matrix2/section2/2_9_4.html#fig

		Traditional in-situ methods for remediation of radioactive contamination are based upon limiting the movement of radionuclides and their exposure to organisms. Phytoremediation of radionuclides is gaining attention as a practical and cost-effective in-situ method (Doty 2008) and is discussed in other sections of this website. Capping and covering pollution to prevent water infiltration or access by animals is common, although it is not a solution to the problem and is limited by the land use goals and future risk of exposure. Stabilization, solidification, and vitrification are potential methods to contain radioactive pollution both in-situ and ex-situ. Vitrification is based upon heating (1600-2000°C) of the contaminated soil, possibly with additives, until the mixture melts and reforms as a glassy mass that is resistant to leaching (Pearl 2000). Solidification and stabilization use mixing agents, such as cement or polymers, to contain the radionuclides and prevent movement (Pearl 2000). These methods can result in soils that are extremely stable from an engineering perspective, but the methods do not remove the radioactivity of the materials; therefore proper storage and monitoring of the treated material is necessary.