Environmental impact of the Central Storage Facility
Monitoring of radioactivity in the CSF area is carried out regularly and we can confirm that the environmental impact of CSF is extremely small or negligible.
We achieve this in several ways:
- Radioactive waste is always in packages from which solid radioactive substances cannot spread into the environment, and the passage of gaseous radioactive substances through the packaging is reduced (e.g. radon).
- At work, we always follow the prescribed procedures and experience of good practice.
- We minimize the risk of an emergency event as much as possible; with physical and technical control, high professional competence of employees, promotion of safety culture and responsibility of all employees ...
- Liquids are collected in an underground reservoir, which is emptied in a controlled manner.
- Air releases from the storage area pass into the environment through filters.
Smaller amounts of non-radioactive waste are also generated when dealing with radioactive waste, for example, waste batteries, waste electronic equipment, uncontaminated packaging and protective equipment. One to two tons of solid non-radioactive waste is generated per year. Wastewater from the facility is collected in an underground tank with a capacity of 3 m3, which is emptied as needed, usually once a year. We hand over solid and liquid non-radioactive waste to authorized waste collectors.
Monitoring of environmental impact
1. Measurements of gamma radiation in the vicinity of CSF
Measurements are made at 6 points, three are at the door and on the roof of the storage facility, and the other three are 10 m, 30 m, and 50 m away from the facility. The largest fluctuations in annual doses (environmental dose equivalent H*(10)) are noticeable at the transport doors, which is the result of intake and amount of packages with RW in an individual year. Differences between individual measurement sites are also affected by soil composition, but less so by radiation from the facility.
2. Measurements of radon concentration in the air
The measurement of radon concentration in the air is carried out using the method with nuclear trace detectors in the immediate vicinity and at a distance of 50 m from the facility. The results of the measurements are comparable with each other and also with the average values typical for outdoor air in Slovenia (around 20 Bq/m3). This proves that the radon emissions from the storage area are very small.
3. Assessment of radon release from the storage space of the facility
Since radon emissions are extremely small, they cannot be measured directly. We evaluate them on the basis of radon concentration measurements in a closed storage area.
4. Measurements of the concentration of radionuclides in ground water
Groundwater is monitored in two wells, one north and one south of the facility in the direction of the Sava riverbed. Thus, possible impacts from CSF could be detected in the southern well if radionuclides were to enter the groundwater. The measurement results have fluctuated considerably in recent years, but in no sample did the measured values exceed the limit values for drinking water. Only natural radionuclides and Cs-137, the presence of which is the result of global environmental pollution from nuclear tests in the past, were found in the water from the wells.
5. Measurements of deposition of radioactive substances from the air
The measuring point for radioactivity of particles that settle from the air onto external surfaces is at a distance of 50 m from the facility. The results of the measurements show that beryllium-7 (Be-7) represents the largest share (around 90%) of the radioactivity that settles on the surface exposed to the outside air. Beryllium-7 is naturally present in the atmosphere and is formed under the influence of cosmic radiation. Environmental contamination with artificial radionuclides from the facility has not been detected so far. The measured values are within the range of normal values .
6. Soil contamination masurements on the meadow in the area of the facility
Measurements of soil contamination in a meadow south of the facility indicate that more than half of the radioactivity is contributed by naturally occurring potassium-40 (K-40). Environmental contamination with artificial radionuclides from the facility has not been detected so far. The measured values are within the range of normal values for the natural environment.
7. Assessment of the effective dose received by representatives of the population as a result of the facility
In order to protect the environment and human health, a dose enclosure is determined for each nuclear facility, i.e. the maximum additional effective dose that residents can receive in the area of the nuclear facility. For the CSF, this value is 0.1 mSv/year (100 μSv/year). The additional exposure of the population outside the fence of the Reactor Center of the "Jožef Stefan" Institute (RC) is actually much lower (0.01% of the dose fence). Even for RC employees, the estimated additional dose is only about 1% of the permitted dose or less (which is about 0.001 mSv/year). The biggest contributor to exposure is the release of radon from the storage area of the CSF.
