Statement

Full text: Can contaminated soil be left in place and, if so, under what circumstances? The contaminated soil problem is typical for nuclear power plants shut down after an accident. Such is the case of the A1 nuclear power plant at the Bohunice site. The safety principles for liquid waste storage were introduced only in 1987, and thus there are hot spots of contaminated soil, predominantly because of poor liquid waste storage practices in the past. The worst contaminated soils have already been removed and are stored in drums nowadays; however, some hot spots still remain. As a mitigation measure, water is being pumped out of the aquifer underneath and discharged into the river. This questionable decision is to prove to the public how environmentally considerate the operator is because the groundwater is seen as a potential source of drinking water and discharge into the river within the concentration limits is not in conflict with legislation. Most recently, a project for contaminated soil landfill has been launched. It is the intention of this project to collect all the contaminated soil stored in drums, remove the hot spots from around the old leaky tanks and dispose of them in a controlled manner. The location for the landfill has been chosen within the Bohunice nuclear site. I have been putting together the safety analysis/performance assessment of the landfill. From the assessor's point of view, I challenge the above mentioned decision on groundwater extraction and discharge into the river. The safety analysis proves that there is sufficient dispersion and retardation of the contaminants in the aquifer before it gets to the nearest well. Quite a large amount of the contaminated soil removed during excavation of the groundworks for the new waste processing centre in Bohunice has been tentatively stored in old unused concrete basins and landscaped to a 'green field' condition. Yet, it is still part of a nuclear facility under regulatory control. A side effect of this safety analysis is that it proved that even the tentative solution to the contaminated soil problem can be requalified as a final solution with no further remediation activities, and the basins can be taken out of regulatory control. So the answer to the question posed above in Slovakia is: Yes, the contaminated soil can be left 'in place' if it is done in a controlled manner with sufficient safety measures in place. That means that the soils will be accumulated in a single place - the landfill with appropriate cap, and some institutional control will be introduced to prevent human intrusion for a certain period of time. In our case the minimum institutional control period being considered is 100 years, which correlates approximately with the time required for decommissioning all of the nuclear facilities on the site (if no new ones are built in place of the existing facilities). (author)