In the period from 22nd September to 24th October 2019, a scheduled outage was carried out on Unit 6 at Kozloduy NPP. The total amount of radioactive waste (RAW) generated during the outage was transported for processing and storage to SD “RAW – Kozloduy”. This RAW is low- and intermediate level radioactive waste: solid RAW – equipment, protective clothing, metals, construction and insulation materials; liquid RAW – aqueous solutions, suspensions, concentrates, oils. The safe transportation of the RAW to SD “RAW – Kozloduy” is of particular importance to the process of management of RAW from outages.
Each transportation operation is performed according to an order or permit to work registered in a “Logbook of permits to work and orders” of the shift supervisor at the Radioactive Waste Processing Plant (RAWPP). For the purpose of ensuring RAW transportation and receipt, a rigorous organisation has been established for implementation of the activities and coordination between the different organisational units, with all the responsibilities precisely allocated. The transportation of solid RAW on the site is in fact carried out in 2 m3 and 6 m3 reinforced concrete containers, as well as in bioshielded containers in a closed loading compartment (radwaste shipping container) of a specialized transport vehicle, which is equipped with a system for securing the load to the floor or the loading section’s walls. The common integrated structure consisting of the package and the system for management thereof shall not break the integrity during normal transportation conditions.
Type of containers
Metal radwaste containers – 2 m3 (load capacity – 0.9 t) and 6 m3 (load capacity – 2.7 t) are transported by a specialized transport vehicle with a closed loading compartment for one or two containers simultaneously.
Bioshielded radwaste containers – 0.2 m3 (load capacity – 0.25 t, tare weight 2.25 t and 2×0.2 m3 (load capacity – 2×0.25 t, tare weight 2 t) are transported one at a time by a specialized transport vehicle of load capacity larger than the weight of the bioshielded container, with closed loading compartment.
The radwaste containers are placed in transport corridors or other temporary collection points for RAW.
Specialized RAW transportation equipment
Any specialized transport vehicle transporting RAW, for the purpose of ensuring safety and protection of personnel, is escorted by a car of the Site Monitoring Section (SM), equipped with a radiation monitoring equipment, personal protective equipment and decontamination equipment, fire extinguishing equipment and portable radiation hazard warning signs, equipment for cordoning the contaminated area off in case of emergency event, prohibitory signs, emergency stop warning signs, audible and light alarm. When transporting RAW, the accompanying Radiological Safety Officer from SM section is responsible for radiation protection outside the Controlled Area.
RAW transportation documents
For each RAW transportation operation, a record containing information about the radiation parameters of the packages, radwaste containers, shipping container and the transport vehicle, is drawn up. Compliance thereof with the RAW transportation criteria is thereby ensured. Transportation activities under special programmes of Kozloduy NPP related to outages of the Units, are staffed by an order of the SERAW’s Executive Director; based on the order, schedules are prepared to ensure twenty-four-hour preparedness for the implementation thereof.
Amount of RAW during the outage of Unit 6 of Kozloduy NPP in 2019
The amounts of RAW received at SD “RAW – Kozloduy” from Kozloduy NPP during the outage, are:
- Compactible solid RAW – 127.89 cubic metres;
- Metal RAW – 7.94 tonnes.