What is RWTF?

• RWTF, Radioactive Waste Treatment Facility supports nuclear R&D by safe treatment and management of radioactive wastes generated during R&D and makes continuous efforts to protect public health and the environment around KAERI from the radioactive wastes generated in KAERI. RWTF was constructed in Dec. 1985 and has been operating since Mar. 1991. RWTF collects, treats and manages all the radioactive wastes genereated in KAERI
  
  
• RWTF consists of an integrated treatment facility (1 basement and 3 stories, 5,940m²), solar evaporation facility (1 basement and 3 stories, 330m²), radioactive waste form examination facility (1 basement and 2 stories, 1,338m²) and 3 storage facilities.
  
  
• For the treatment of liquid waste, there are an evaporation process and a bituminization process in RWTF. Also, for the treatment of solid wastes, a compactor with 90 ton capacity has been installed. At the solar evaporation facility, there is a storage pool with 860 ton capacity and using 1,032 units of evaporation media, very low level liquid waste is treated. 1 concrete hot cell installed in radioactive waste form examination facility is used for the test of waste form integrity. In addition to that, 3 storage facilities with total capacity of 16,018 drum (of 200ℓ drum) are used for interim storage of low and intermediate level solid waste.
  
  
• Radioactive wastes generated in KAERI are extremely varied in radionuclides, form and radioactivity due to the wide objectives of nuclear R&D. Also generation time and amount of radioactive waste are unpredictable. As a result, an appropriate treatment method will be applied to each radioactive waste stream. RWTF staff members do their best for safe management of all the radioactive wastes in KAERI by continuous improvement of the treatment and process. In addition to the all, the radioactive wastes in KAERI will be safely transported to the final repository in economic and efficient manner by RWTF.
  
  

Schematic diagram of the radioactive waste treatment process

• The radioactive wastes are treated and managed based on their characteristics. The very low-active liquid waste is directly transported to the solar evaporation facility and treated there. On the other hand, low- and medium- active liquid waste is collected at different tank, based on the radioactivity level and treated at the treatment facility. The low-active liquid waste is evaporated while the medium-active waste is bituminized with concentrate generated at the evaporation process and spent resin. Condensate generated at the evaporator is classified as very low-active liquid waste, and then transported to solar evaporation facility. Low level solid waste is compacted or cut and then stored. In addition to that, there are decontamination processes for reuse or regulatory clearance of slightly contaminated equipment.
  
  
  
  
  
  
• Treatment process of the liquid radwaste
  • The liquid radioactive waste is collected and stored based on the radioactivity level. At RWTF, there are 3 storage tanks for very low-active liquid waste, 3 storage tanks for low-active liquid waste, 1 tank for medium-active liquid waste and 1 tank for corrosive-active liquid waste. The liquid waste is treated using an evaporation process, bituminization process or solar evaporation process, and there is no liquid effluent from KAERI to the environment.
    
    
  
  
  
  
• Treatment process of the solid radwaste
  • The solid radioactive wastes generated in various forms are collected in 200ℓ drum or 50ℓ container based on their radioactivity level. While low level wastes stored after volume reduction, intermediate level wastes are stored in concrete well for 5~6 years and then reclassified for treatment or further storage.
    
    
  
  
  
  
• Volume reduction and Decontamination process of the solid radwaste
  • Compressible solid radwastes are compacted using a 90 ton compactor and then stored. Slightly contaminated equipment is decontaminated for reuse or regulatory clearance. A soaking tank, sand blaster and dry ice pellet blaster are used for the decontamination.
    
    
  
  
  
  

Characterization of radwaste form´s integrity

• The radioactive wastes at KAERI will be finally disposed after the operation of therepository in 2009. The schematic diagram of radioactive waste management from collection to disposal is as shown.
  
  
  
  
  
  
• Hot cell
  • Hot cell is a concrete cell(14m (L) × 6.5m (W) × 6.5m (H)) and a multipurpose cell to handle high activity materials equipped remote controlled devices, CCTV, radiation monitoring system
  
  
  
  
  
• Coring waste form
  • To identify mechanical, physical and chemical characteristics, test specimens are taken out of 200 ℓ wast form.
  
  
  
  
  
• Characterization of radwaste form
  • Radwastes are disposed in a disposal site as solidified waste forms for their complete isolation from the human environment. The waste forms serve as the first protection against the release of radionuclides.
  • The properties of waste forms are variabl depending upon the waste types, and physicochemical properties of waste. Therefore, radwaste forms must be held to sufficient degree of strength to maintain its structural safety in the disposal site and be better anti-leaching properties not to be leaked by free-standing water, rainwater and underground water.
  
  
  
  
  
  

Safety of radioactive waste management

• To secure the safety of radioactive waste management, monitoring cameras are installed in the storage facilities and the solar evaporation facility. Using the cameras, facility inspections and fire prevention efforts are monitored. Additionally, to secure the transparency of the management, the storage status of radioactive wastes is opened to the public.