On 25 April 2017, the operator responsibilities for the Asse II mine as well as the Konrad and Morsleben repositories were transferred to the Federal Company for Radioactive Waste Disposal (Bundesgesellschaft für Endlagerung mbH, BGE). This website of the Federal Office for Radiation Protection (BfS) will therefore no longer be updated and displays the status as on 24 April 2017. You will find current information at the BGE: www.bge.de

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From iron ore mine to final repository (text version)

Text version of the video "From iron ore mine to final repository"

Early morning mist swirls around the Konrad One mine, where - until 1976 - iron ore was mined. On the other side of the Salzgitter branch canal is the Konrad Two mine. A provisional winding tower has been erected above the shaft formerly used for mine ventilation and as an emergency escape route. On completion of the repository it will be used to transport radioactive waste underground. Beforehand, parts of the mine require remedial work and Shaft 2 has to be prepared for encasement operations.

The Konrad mine will become a final repository for radioactive waste with negligible heat generation, which includes all low-level and the majority of intermediate-level radioactive waste. Waste, produced during 40 years of operations in German nuclear power plants and research reactors and also from decommissioning these facilities. Waste that previously was stored in interim surface storage depots - such as here in Karlsruhe. In contrast to high level radioactive waste, it contains only 1 percent of overall radioactivity, but accounts for more than 90 percent of the total volume of radioactive waste. Everyday articles - such as protective clothing and packaging material - become contaminated through use in nuclear facilities and are also classed as radioactive waste. When nuclear power plants or research reactors are dismantled, components and tools must also be carefully disposed of, due to surface contamination. In an intermediate stage, the waste - packed in drums - is reduced in volume. The contaminated, compacted material is then sealed in another drum, in preparation for final storage in the Konrad mine.

A number of local residents - who were against the repository - clearly expressed their opposition. Questions were asked. What types of radioactive waste will be stored here? Are we to become Europe's Number 1 rubbish dump? For more than 20 years, experts assessed the suitability of the mine as a repository for nuclear waste. Opponents challenged their findings and the legitimacy of waste disposal. During the planning approval procedure, numerous voices raised objections. In the 75 day public hearing their views were discussed and - where appropriate - incorporated in the planning process. In 2002 the Ministry of the Environment of Lower Saxony approved the plans to build and operate the Konrad final repository.

The planned facility at Shaft 2. The emplacement galleries are protected from groundwater and from the Salzgitter branch canal located above the mine - by an approximately 400 meters thick, impervious rock and clay-bearing barrier. The first storage fields will be excavated more than 800 meters underground, relatively close to Shaft 2, with the aid of huge road-heading machines. The machines are able to penetrate roughly 10 meters a day into the rock strata. The emplacement galleries will extend up to 800 metres into the iron-ore rock. Later, these galleries will serve as the final storage place for low and intermediate-level radioactive waste - packed in containers. Before the drums with the radioactive waste are transported to Konrad, they are additionally sealed in steel containers. Intermediate-level waste is packed in containers with concrete-walls, to protect the surroundings against higher radiation levels. Before being transported to the repository, the containers are filled with concrete. Exterior surfaces must comply with official threshold values for packaged radioactive waste. In this measurement, direct gamma radiation is one hundreth of the statutory threshold. The concrete and container walls reduce radiation; complete shielding is not possible. With increasing distance, radiation becomes significantly less and is, eventually, hardly measurable.

The area surrounding the final repository and a look into the future. Every week, an average of 10 trucks - each carrying one container as well as a train with 20 freight-wagons - transporting up to 40 containers - will arrive at the site. The waste is encased so securely, that even in the event of an accident, no inadmissable release of radioactivity into the environment is possible. For road and rail transport there are strict threshold values. The maximum radiation dose rate measured on the surface of a freight wagon must not exceed 2 millisieverts per hour. 2 meters away, it must not exceed 0.1 millisievert per hour, a twentieth of the maximum value. In practice, calculations show that the dose will probably be approximately 0.03 millisievert per hour. However, even assumming the maximum values, radiation at a distance of 30 metres from a freight wagon, will be the same as the cosmic radiation a person in an aircraft is exposed to. The radioactive waste will arrive at the repository via a new rail spur and a new access road.

The transfer station. Only a limited number of transport vehicles will be allowed in here at any one time. Even the impact of a plane crash or a terrorist attack will not have any serious radiological consequences. A 30 tonne gantry crane lifts the container from the road vehicle or freight wagon and places it on a flatbed truck, specially built for transport within the mine. At the Incoming Monitoring Station, various tests ensure that each container meets the acceptance criteria. A Scanner registers the data and compares them with the accompanying documentation. Afterwards the surfaces of the containers are checked for possible contamination in what’s known as a "wipe test". In a third step radiation levels are measured to determine the "local dose rate".

Just a few hundred meters from the transfer station, is the village of Bleckenstedt. The site will later be visible from here. But a relevant dose of radiation will only be measurable in the immediate vicinity of the transfer and buffer facilities, and may not exceed 1 millisievert per annum. Even if someone spent a whole year there, the maximum radiation dose they would be exposed to, would be considerably lower than the statutory threshold. Any waste water arising during transfer operations, is collected on site and - only after passing stringent safety checks - is it discharged into the Aue riverlet. There are no restrictions for local agriculture or on any foodstuffs produced in the region.

In the long term the only way to prevent the radioactive waste from coming into contact with the biosphere, is by storing it deep underground in geological formations. In the Konrad mine this is ensured by the up to 400 meter thick layer of clay and rock strata above the storage site. To minimize risks underground - for example fire hazards - transportation in the mine is subject to stringent safety precautions. During each shift, 17 containers can be transported and stored underground. In single-shift operation that's roughly 4,000 per year.

At the entrance to the emplacement gallery, a stacker lifts a container off the flat-bed truck. It will take decades before all the waste - planned for the Konrad mine - has been stored and emplaced. Approximately 7,000 containers, for example, are in the interim storage depot in Karlsruhe. By 2040 it is estimated that the volume of radioactive waste in Germany will amount to 50,000 of these containers! That is the amount of waste that Konrad is licensed to handle. Inside the containers, certain atoms - called radio nuclides - are in a constant state of decay. Direct gamma radiation is already partially stopped within the containers and is also unable to penetrate layers of clay and rock. However, small amounts of gaseous radioactive particles can be emitted into the exhaust air. Radioactivity carried in this way, is constantly monitored and measured by sensors installed in the exhaust air stream. Above ground, sensors near the transfer facility continually monitor the current "local dose rate". To maintain the highest degree of safety both above and below ground, the emplacement galleries will be filled section by section. Each section will first be closed with a concrete wall before being backfilled with excavated material, mixed with concrete. This means that the radioactive waste can never be recovered but no radioactivity can be released. Once all the sections have been filled, each gallery will be permanently sealed and at the end of storage operations both Shafts 1 and 2 will be backfilled. Computer simulations have shown that fossil water, which originated when the rock strata were created, could slowly migrate in a north-easterly direction. Any radioactive substances carried with it, would gradually further decay. In the worst case scenario, after approximately 300,000 years, the water could possibly reach the surface. By then, contamination would be negligible.

So much for the look into the future. What will remain, is the uneasy feeling of living above a final repository, but also the knowledge of the protection offered by hundreds of metres of clay and iron-ore rock.

State of 2015.06.01

Transfer of operator responsibilities

On 25 April 2017, the operator responsibilities for the Asse II mine as well as the Konrad and Morsleben repositories were transferred to the Federal Company for Radioactive Waste Disposal (Bundesgesellschaft für Endlagerung mbH, BGE). Previously, the responsibility for the projects was with the Federal Office for Radiation Protection (BfS). The foundations for the change of operatorship are laid down in the "Act on the Realignment of the Organisational Structures in the Field of Radioactive Waste Disposal", which became effective on 30 July 2016. The BfS focusses on the federal tasks of radiation protection, for example in the field of defence against nuclear hazards, medical research, mobile communication, UV protection or the measuring networks for environmental radioactivity.

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