Radioactive Contamination of the Soil: Assessments of Pollutants Mobility with Implication to Remediation Strategies

Abstract

Accidental releases, nuclear weapons testing, and inadequate practices of radioactive waste disposal are the principal human activities responsible for radioactive contamination as a new and global form of soil degradation. Understanding the radionuclide distribution, mobility and bioavailability, as well as the changes caused by the variation of environmental conditions, is essential for soil rehabilitation. This chapter aims to highlight the importance of evaluating radionuclide distribution, for the selection of proper in situ or ex situ remediation strategy. Attention was focused onto remediation methods based on radioactive pollutants redistribution, for enhanced separation (chemical extraction) or containment (in situ immobilization). When the excavation and off-site leaching treatments are uneconomic, impractical, or unnecessary, in situ stabilization by the addition of appropriate reactive materials is an alternative approach. The optimization of factors in control of chemical leaching methods, selection of costeffective immobilization agents, especially among suitable wastes and by-products, and verification of long-term effects of remediating actions are the major challenges for future investigation in this field. Furthermore, the improvement and standardization of the methods for radionuclide speciation are necessary to enable comparison between studies and monitoring of the effects achieved by the soil treatments.

Integration of Processes of Radionuclide-Contaminated Territories Decontamination in the Framework of Their Ecological-Socio-Economic Rehabilitation

“…For example, the accumulation of 90 Sr by plants in most cases is inversely proportional to the absorption capacity of the soil and the amount of exchangeable Ca and for 137 Cs-K. As noted, the entry of radionuclides into plants and their accumulation in the crop is largely determined by the content in the environment of their chemical analogs. As the amount of calcium and potassium in the soil or nutrient medium increases, the supply of 90 Sr and 137 Cs to plants decreases Smičiklas et al, 2016].…”

Novel Hydroxyapatite Beads for the Adsorption of Radionuclides from Decommissioned Nuclear Power Plant Sites

“…In recent years, increasing attention has been paid to the removal of radioactive pollutants from aquatic ecosystems due to their frequent and widespread detection [1,2]. In addition to natural radionuclides, the occurrence of radioactive pollutants has become widely recognized due to their introduction through anthropogenic sources, such as nuclear power plants, weapons, medicine, industrial radiography, studies, accidental releases, and inadequate practices of radioactive waste disposal [3][4][5].…”

“…In addition to natural radionuclides, the occurrence of radioactive pollutants has become widely recognized due to their introduction through anthropogenic sources, such as nuclear power plants, weapons, medicine, industrial radiography, studies, accidental releases, and inadequate practices of radioactive waste disposal [3][4][5]. Among the various noxious radionuclides, 137 Cs, 60 Co, 63 Ni, 55 Fe, 90 Sr, 226 Ra, 232 Th, and 238 U were reported as the key artificial radioactive contaminants [1][2][3]. Remarkably, 60 Co has been identified as a significant environmental issue because it generally prevailed in aqueous wastes that are discharged from nuclear facilities [3,6].…”

Nitrification Process in a Nuclear Wastewater with High Load of Nitrogen, Uranium and Organic Matter under ORP Controlled

“…If radioactive effluents are discharged directly into the environment, they will pollute water, atmosphere, and soil, threatening the environment and human health [7]. So, radioactive effluent treatments are becoming one of the most important issues that environmental legislation has to address [8].…”