Industries that use or produce radionuclides have unintentionally released these substances into surrounding soils and sediments. To address this problem, Beautiful Environmental Construction (BEC) Co. developed the BEC’s Radioactive Soil Decontamination (BERAD) system to remove contaminants and reduce the volume of radionuclide-contaminated soils. Owing to the limited availability of radioactive isotopes such as 60Co, 90Sr, 137Cs, and uranium-contaminated soil, naturally occurring elements in soil were used in this demonstration. The soil was divided into six size fractions via manual wet sieving and the BERAD system. Then, the concentrations of uranium, cobalt, strontium, cesium, and iron in each fraction were measured. The results of both separations showed that a considerable amount of each element is retained in the finer size fractions (<0.2 mm). After BERAD separation, the corresponding values yielded 53% uranium, 45% strontium, 66% cobalt, and 53% cesium in the fine size (<0.2 mm) fractions of 35% by weight. The study found that the concentrations of these elements increased as the particle sizes decreased. Iron and micaceous minerals played a significant role in retaining the elements. The pilot scale BERAD system yielded results that were similar to those obtained via laboratory wet-sieving and was successfully demonstrated as a soil washing technology.

Economical radioactive soil treatment technology is essential to safely and efficiently treat of high-concentration radioactive areas and contaminated sites during operation of nuclear power plants at home and abroad. This study is to determine the performance of BERAD (Beautiful Environmental construction’s RAdioactive soil Decontamination system) before applying magnetic nanoparticles and adsorbents developed by the KAERI (Korea Atomic Energy Research Institute) which will be used in the national funded project to a large-capacity radioactive soil decontamination system. BERAD uses Soil Washing Process by US EPA (402-R-007-004 (2007)) and can decontaminate 0.5 tons of radioactive soil per hour through water washing and/or chemical washing with particle size separation. When contaminated soil is input to BERAD, the soil is selected and washed, and after going through a rinse stage and particle size separation stage, it discharges decontaminated soil separated by sludge of less than 0.075 mm. In this experiment, the concentrations of four general isotopes (A, B, C, and D which are important radioisotopes when soil is contaminated by them.) were analyzed by using ICP-MS to compare before and after decontamination by BERAD. Since BERAD is the commercial-scale pilot system that decontaminates relatively large amount of soil, so it is difficult to test using radioactive isotopes. So important general elements such as A, B, C, and D in soil were analyzed. In the study, BERAD decontaminated soil by using water washing. And the particle size of soil was divided into a total of six particle size sections with five sieves: 4 mm, 2 mm, 0.850 mm, 0.212 mm, and 0.075 mm. Concentrations of A, B, C, and D in the soil particles larger than 4 mm are almost the lowest regardless of before and after decontamination by BERAD. For soil particles less than 4 mm, the concentrations of C and D decreased constantly after BERAD decontamination. On the other hand, the decontamination efficiency of A and B decreased as the soil particle became smaller, but the concentrations of A and B increased for the soil particle below 0.075 mm. As a result, decontamination efficiency of one cycle using BERAD for all nuclides in soil particles between 4 mm and 0.075 mm is about 45% to 65 %.