Radioactive Solid Waste Storage Research Articles

HOLDER DESIGN EVALUATION OF GAMMA AREA MONITOR IN SOLID RADIOACTIVE WASTE INTERM STORAGE ROOM OF RADIOMETALURGY INSTALLATION

HOLDER DESIGN EVALUATION OF GAMMA AREA MONITOR IN SOLID RADIOACTIVE WASTE INTERM STORAGE ROOM OF RADIOMETALURGY INSTALLATION . Radiometalurgy Installation (RMI) is one of Non-Reactor Nuclear Installation where post-irradiation examination (PIE) take place, which give gamma radiation ranged from one µSv/h to the order of mSv/h. The PIE activity produce high-activity radioactive waste as a by-product that stored temporarily in RMI Building. The temporary solid radioactive waste storage room is equipped with in situ gamma area monitor (GAM) as a mean of external radiation protection for radioactive waste operator. This research is conducted to understand the characteristic of GAM Detector and evaluate the positioning of detector, the design of detector holder, and the threshold setting of radiation detection alarm in The temporary solid radioactive waste storage room. The research is conducted by measuring a standard radiation source Cs-137 with the activity of 1 µCi using GAM Detector with variation of position in 4 point, which are in the middle-front of detector, the front-side of the detector vessel, the middle of detector vessel, and back-end of detector vessel, along with variation of source to detector distance, which are 0 cm, 10 cm, 20 cm, 30 cm, 40 cm, and 50 cm. The measurement done in the middle-front of the detector give the highest dose of gamma radiation measured which are 5.63, 4.20, 0.58, 0.28 μSv/h. The result of gamma radiation dose measurement by the detector shows that the closer the source to middle-front part of the detector the higher the radiation measured. The holder design of the gamma radiation detector used in the current GAM device provides information on the gamma radiation dose rate of 74.26% of the actual dose rate. The detector holder currently positioned the middle-front side of the detector upwards therefore the design of detector holder needs to be modified in order for the detector to measure the dose more effectively and give the true number of dose measured

Approaches to rehabilitation of radioactive contaminated territories

AbstractBACKGROUNDAccidents at nuclear fuel cycle plants may lead to contamination of areas of land and water. Cheap and available sorbents including natural aluminosilicates can be used for rehabilitation and decontamination of large volumes of radioactively contaminated water, including drinking water, prevention of migration of radionuclides into ground and surface waters through the soil and returning contaminated soil to farming.RESULTS AND DISCUSSIONA comparative study of sorption properties of various natural and surface‐modified aluminosilicates with respect to caesium is made. It is shown that sorption features of surface‐modified aluminosilicates for Cs were improved by 100–1000 times compared with respective natural aluminosilicates. It is shown that surface modification of glauconite by a mixed nickel–potassium ferrocyanide phase allows it to considerably increase its specificity (caesium distribution coefficients (2.9 ± 0.8)×103 mL g‐1 for natural and (4.5 ± 0.5)×105 mL g‐1 for modified glauconite) as well as making it selective to caesium in the presence of other alkaline ions and also provides irreversible caesium sorption.CONCLUSIONSDue to improved features, modified aluminosilicates can be more successful than natural ones when used for rehabilitation of radioactive contaminated territories (including agriculture) and water areas, as well as for decontamination of liquid radioactive wastes and for creation of geochemical barriers in solid radioactive waste storage. © 2013 Society of Chemical Industry

On-site radioactive soil contamination at the Andreeva Bay shore technical base, Northwest Russia

The radioactive waste (RAW) storage site at Andreeva Bay in the Russian Northwest has experienced radioactive contamination both as a result of activities carried out at the site and due to incidents that have occurred there in the past such as accidental releases of radioactive materials. The site is an interesting case study for decommissioning due to the extremely large amounts of radioactivity present at the site and the conditions under which it is stored; very little has been previously published in the scientific literature about this site. This paper complements the paper describing dose rates at Andreeva Bay which is published in this issue of Journal of Environmental Radioactivity by the same authors. This study presents new data related to the activity concentrations of 137Cs and 90Sr in surface soils and measurements of α- and β-particle fluxes taken at different areas around the site. Limited data on 60Co is also presented. The results of the study indicate that the main areas of site contamination are associated with the former spent nuclear fuel storage facility at Building 5, due to accidental discharges which began in 1982. Substantial contamination is also observed at the solid radioactive waste storage facilities, probably due to the ingress of water into these facilities. More than 240 samples were measured: maximum contamination levels were 1 × 10 6 Bq/kg 137Cs (mean value 4.1 × 10 5 Bq/kg) and 4 × 10 6 Bq/kg 90Sr (mean value 1.2 × 10 5 Bq/kg). Localised patches of α and β contamination were also observed throughout the site.

Seasonal Trends in Environmental Tritium Concentrations in a Small Forest Adjacent to a Radioactive Waste Storage Area

Tritium (HTO) concentrations were studied for an entire year in a floodplain forest adjacent to a low-level radioactive solid waste storage area (SWSA No.5) at Oak Ridge National Laboratory (ORNL) near Oak Ridge, Tennessee, USA. Tritium in soil was the principal source of HTO to the deciduous forest. Evaporation from the surface soil along with transpiration from tree leaves both contributed to HTO in the forest atmosphere. During the growing season, transpiration was the principal contributor of HTO to the forest atmosphere, while during the dormant season, the main source of atmospheric HTO was evaporation from the surface soil. Seasonal changes and the characteristics of vegetation will influence die relative importance of evaporation and transpiration as sources of atmospheric HTO near the ground in temperate deciduous forests.

Radiological safety assessment for a low-level radioactive solid waste storage facility: preliminary risk evaluation by reliability techniques.

Radiological safety assessment for a low-level radioactive solid waste storage facility: preliminary risk evaluation by reliability techniques.