AVR (Jülich)

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AVR (Jülich)
AVR Jülich (2009) with material lock for dismantling
AVR Jülich (2009) with material lock for dismantling
location
AVR (Jülich) (North Rhine-Westphalia)
AVR (Jülich)
Coordinates 50 ° 54 '11 "  N , 6 ° 25' 16"  E Coordinates: 50 ° 54 '11 "  N , 6 ° 25' 16"  E
Country: Germany
Data
Owner: Working group Versuchsreaktor GmbH
Operator: Working group Versuchsreaktor GmbH
Project start: 1961
Commercial operation: May 19, 1969
Shutdown: Dec 31, 1988

Decommissioned reactors (gross):

1 (15 MW)
Energy fed in since commissioning: 1,506 GWh
Was standing: July 25, 2007
The data source of the respective entries can be found in the documentation .
f1
Reactor building (only the material lock is visible)

The experimental nuclear power plant AVR Jülich (Arbeitsgemeinschaft Versuchsreaktor Jülich) was the first German high-temperature reactor (HTR). The system was used to generate electricity; it was not a research reactor for neutron production.

The AVR is based on a concept by Farrington Daniels , the inventor of pebble bed reactors , from which the name “ Daniels pile ” goes back. Rudolf Schulten is often referred to as the spiritual father of the AVR .

The facility is located in Jülich directly next to the site of the Jülich Research Center (FZJ) on an area leased by the state of North Rhine-Westphalia. The operator and owner was a consortium of 15 municipal electricity companies. The AVR had a net electrical output of 13  megawatts and was operated from 1966 to 1988. Several defects and incidents occurred; Critics see evidence that the reactor is even damaged . The AVR operation and possible hazards during operation were examined by external experts from 2011 to 2014; According to the final report from April 2014, there were serious hidden problems and misconduct. For example, in 1978 technicians deliberately manipulated the reactor control so that an emergency shutdown of the reactor was avoided; They did not shut down the reactor until six days after an incident began. FZJ and AVR publicly admitted negligence in 2014.

The dismantling of the AVR is considered to be extraordinarily difficult, lengthy and cost-intensive. Since the operators were overwhelmed, dismantling and disposal are commissioned and paid for by government agencies. In 2003 the public authorities also formally became the owner of the AVR and its nuclear waste. The interim storage of 152 castors with AVR fuel elements in the FZJ castor storage facility has been a source of controversy since 2009: its permit expired in 2013 because sufficient safety evidence could not be provided and it did not pass a stress test; it was tolerated by the authorities until mid-2014. On July 2, 2014, the nuclear supervisory authority issued an evacuation order for the interim storage facility. In 2014 it was provided with a massive concrete wall to protect against terrorist plane crashes. Since 2012 there have been plans to export the AVR castors to the USA because of the extraordinarily high disposal costs. Since 2015, the public prosecutor's office has been investigating Forschungszentrum Jülich on suspicion of unauthorized handling of nuclear fuel in connection with the AVR castors.

history

In 1956, an interest group was set up to prepare the AVR for construction. In 1959 this became the "Arbeitsgemeinschaft Versuchsreaktor GmbH" (AVR GmbH), a consortium of 15 local electricity suppliers under the leadership of Stadtwerke Düsseldorf as the builder and operator (other shareholders, including Stadtwerke Aachen, Bonn, Bremen, Hagen, Hanover, Munich, Wuppertal). The feasibility and functionality of a gas-cooled, graphite-moderated high-temperature reactor for electricity generation should be demonstrated. The AVR was built by BBC and Krupp from 1961 . The AVR planning and construction took place on an almost purely industrial basis, until 1964 under the direction of Rudolf Schulten. There was federal financial support. The prerequisites for building the AVR were essentially created by Leo Brandt .

From 1964 (in that year Schulten became director of the FZJ), the FZJ began to focus more on the pebble bed reactor. The AVR became critical for the first time in 1966, and in 1967 the power plant fed electricity into the public grid for the first time. Information on the construction costs fluctuates between DM 85 and 125 million (added up during the construction period, without inflation adjustment). The AVR GmbH was formally an independent company until 2003, but from around 1970 it was de facto dependent on the FZJ: The FZJ paid high operating subsidies to the AVR GmbH in order to ensure continued operation, since the electricity generated in the AVR was only a small part of the Operating costs covered. In the mid-1970s, for example, electricity revenues of DM 3 million per year were offset by operating costs without fuel supply and disposal of DM 11 million per year. FZJ's support for the AVR also included the procurement and return of the fuel element balls: FZJ was and remained the owner of the AVR fuel elements until September 1, 2015. In contracts between AVR GmbH and FZJ, details of the AVR operation were specified. In addition, the AVR operation was scientifically supported by the FZJ.

In the first years, the AVR was operated with cooling gas outlet temperatures of 650 ° C to 850 ° C, from February 1974 to the end of 1987 nominally up to 950 ° C. The latter high temperatures are described in Jülich as the world record for nuclear plants, but they were far exceeded in the US test reactor UHTREX . They should demonstrate the AVR suitability for coal gasification and thus contribute to a longer-term perspective for coal production in NRW. The planned electrical efficiency of 38% could not be achieved despite the high gas temperatures achieved (real efficiency gross 32%, net 29%), probably due to gas bypasses around the steam generator. After the discovery of AVR core areas with extremely high temperatures, however, 810 ° C could not be exceeded in the last year of operation. The planned conversion of the AVR into a plant for coal gasification was not approved, nor was the construction of an advanced AVR-II in Jülich. After 21 years of operation, the reactor was shut down on December 31, 1988. In total, it produced around 1.7 billion kilowatt hours of electricity (gross) and fed 1.5 billion kilowatt hours of electricity into the public grid. The VDI in 1990 presented a review of the trial operation of the AVR from the point of view of the proponents of this technology . According to critics, the condition of the AVR at the end of operation corresponds to that of a wrecked reactor with core damage . The strontium contamination in the reactor vessel is then comparable to that of the TMI reactor after its core meltdown .

In the years that followed, the decommissioning concept was changed from “ safe enclosure ” to “ gutting ” to “complete dismantling”. For this purpose, the AVR was integrated into the federally owned company Energiewerke Nord (EWN) in 2003 , which has specialized in the dismantling of nuclear power plants. This was preceded by a report by the Federal Audit Office , which massively criticized the inadequate progress of the AVR disposal project 1989–2002 under Jülich management and recommended other project managers than FZJ and AVR. The EWN CEO saw the demolition of the AVR as one of the most difficult tasks his company had to face to date. Preparations are currently underway for the complete removal of the facility. In 2006 a 60 × 40 meter material lock made of steel was built in front of the reactor building to enable the reactor container to be discharged.

According to the schedules from 2009, the dismantling work should be completed by 2015 and the state of "green field" should be established, while the reactor vessel is temporarily stored 200 m away for at least 60 years. Currently (2014), the Template: future / in 2 yearsend of the redevelopment of the AVR site is not expected until 2022 . Due to the high level of contamination of the cooling circuit, the dismantling causes considerable problems. In 2000, the operators admitted that the β-contamination ( 90 Sr ) of the AVR reactor is the highest of all reactors and nuclear plants in the world and is also present in the most unfavorable form, namely dust-bound. The content of long-lived 14 C, which was created through extensive use of contaminated but cheap coal stone instead of graphite and careless handling of nitrogen in reactor operation (see here ), as well as 137 Cs, 60 Co, is also extraordinarily high and a hindrance to disposal and tritium.

construction

Construction of the AVR reactor

In contrast to the normally used arrangement of the steam generator next to the reactor core, the steam generator in the AVR was arranged above the reactor core, which results in a particularly small amount of space required. The shutdown rods are retracted from the bottom of the reactor in separate graphite columns that penetrate the reactor core. The cooling fans and the ball extractor are also located on the underside of the reactor. Derived from the vertical arrangement and the small space requirement, BBC / HRB had plans for an HTR-100 industrial power plant that was to be used directly in industrial plants for process heat and electricity generation. During the operation of the AVR, however, it became apparent that the design must in any case prevent water from penetrating into the reactor core and a vertical arrangement consequently being risky. During the construction of the commercial prototype THTR-300 in Hamm-Uentrop, the steam generators were therefore arranged next to the core and the control rods were moved directly into the pebble from above without graphite columns, which enables a more compact core structure. However, these control rods, which move directly into the pebble, turned out to be a faulty design, as too many fuel elements were destroyed, so that newer concepts in this regard are again based on the AVR. The arrangement of steam generators in separate containers next to the core container reduces the likelihood of liquid water penetrating the core, but increases the risk of air ingress with graphite fire due to the connection line between the containers as a weak point. The integrated container concept of the AVR was not completely abandoned, but lives on in some project proposals.

The AVR reactor vessel is roughly the same size as that of the Krümmel nuclear power plant , but its electrical output was 100 times greater.

Technical specifications AVR experimental reactor
thermal performance 46 MW
net electrical power 13 MW
Medium power density 2.6 MW / m³
Reactor core height / diameter 2.8 m / 3 m
Fuel and breeding material 235 U and 232 Th
Average fuel temperature 642 ° C
Maximum fuel temperature 1041 ° C
Height of reactor pressure vessel 24.9 m
Reactor pressure vessel diameter 5.8 m
Material reactor pressure vessel steel
Moderator material graphite
Coolant Hey
Inlet temperature 275 ° C
Average cooling gas outlet temperature up to 720 ° C (up to 1970),
up to 760 ° C (1970–1974),
up to 950 ° C (1974–1986),
up to 810 ° C (1986–1988)
pressure 10.8 bar
Live steam temperature 505 ° C

Accidents

Pebble bed reactors have the fundamental disadvantage that real-time measurements cannot be made in the reactor core - unlike in conventional NPPs. As far as the incident related to the AVR core, it could only be detected with a time delay and only imprecisely. In the opinion of critics, this circumstance was and is used to conceal or disguise incidents.

On July 1, 1973, "Increased discharge of radioactive tritium into the atmosphere" was registered as a reportable event at the Federal Office for Radiation Protection . In the years 1967 to 1973 tritium got into the area because the tritium filter was not functional during this time. Specific emission values ​​were not published. The tritium production in the AVR was unusually high due to lithium contamination in some components (coal stone), so that significant emissions could have occurred. An extensive turbine oil fire occurred on February 11, 1971 after a leak in an oil line had only been temporarily sealed. As a presumed consequence of an air ingress (100 m³) on May 10, 1971, fuel element damage occurred in the mid-1970s (so-called jacket potato effect ). On September 7, 1971, 50 liters of corrosive hydrochloric acid found its way into the feed water of the secondary circuit. In 1974 it was discovered that due to the lack of upward radiation shielding - a serious misinterpretation by the BBC - considerable radiation exposure from Skyshine (gamma rays and neutrons reflected in the air) occurred up to approx. 100 m outside the fence (see bio-sign 1 in the illustration of the structure of the AVR reactor missing in the upper spherical cap). Total dose rates of more than 10 mSv per year were measured within the premises, and up to 4 mSv / a at the fence. On the roof of the reactor, the dose rates even amounted to 2 mSv / h, i.e. 17 Sv / a. After the supervisory authority threatened to shut down the reactor in mid-1975, provisional shielding measures were taken with which the neutron radiation could be reduced by half. Because of the remaining pollution, part of the forest outside the AVR site had to be closed to the public. In the first half of 1976, the release of cesium and strontium from the fuel elements into the cooling circuit increased by more than a thousand times. There is still no satisfactory explanation for this. Critical observers suspect a previously hidden incident in which the reactor was not adequately under control due to excessive fissile material concentrations in the outer core area, which led to very high temperatures. On October 31, 1980, a shutdown rod stuck during a test reactor shutdown. In 1982, 120 liters of oil flowed from the helium blowers into the main cooling circuit, where large amounts of soot and deposits formed due to the breakdown of the oil. On June 11, 1987, radioactivity reached the area through a leaky drain valve in the containment.

Until 1982, the combustion measuring system in the reactor, with which the residual fissile material content of the removed spheres was to be determined, actually did not work, after that it was only unsatisfactory. Therefore, the distribution of fissile material in the reactor, which was supposed to be influenced by the targeted return of balls of suitable burn-up to the edge or inner area, could only be poorly controlled. In 1984 it was also found that the reactor core was loaded asymmetrically due to a design error in the ball feeder, which resulted in an unbalanced load. Both should have led to considerable deviations from the intended operating parameters. However, since pebble bed reactors cannot be equipped with continuously working measuring devices in the core, no precise information can be given. The errors in the burn-up measurement also mean that the contents of the individual castors with used AVR fuel assemblies are only known imprecisely.

From May 13-22, 1978, as a result of a leak in the superheater section of the steam generator, 27.5 t of water entered the primary He circuit and thus into the reactor core. At that time, this accident was only declared as (at that time the lowest) category C (no or only minor safety significance) , although it was due to the positive reactivity effect of the water (possibility of immediate supercriticality of the reactor) and the possible chemical reaction of the water with the graphite with formation explosive gases is one of the most dangerous accidents for a high temperature reactor. The accident was probably only without serious consequences because the core only had temperatures below 600 ° C after larger amounts of water had penetrated and because the leak remained small. Nevertheless, the reactor remained switched off for a long time and then had to be "dried" for almost a year by driving at a reduced temperature in order to remove the residual water. Since then there has been radioactive soil and groundwater under the reactor from the accident. As a result of the accident, the foundation chamber water, which is in direct contact with the environment, was significantly radioactively contaminated with 90 Sr and tritium . While strontium is still present in the area of ​​the reactor, tritium has probably (this is no longer traceable) removed with the groundwater. The activity of tritium in the accident water was by a factor of 70 to 300 higher than that of strontium. This groundwater contamination by tritium at the AVR was, according to Rainer Moormann , a former employee of the FZJ, the largest radioactive groundwater contamination by a civil nuclear facility in Western Europe to date. As a result of this incident, precautions were taken in subsequent designs of high-temperature reactors to prevent the core from being flooded with liquid secondary coolant. However, these precautions increase the risk of leaks in the primary circuit enclosure and thus of air ingress with reactor fire.

In 2008, an FZJ report was published by Moormann, according to which the excessive radioactive contamination of the reactor can be attributed to insufficient monitoring of the reactor core and to prolonged operation at impermissibly high temperatures. This u. a. led to the fact that fission products could escape from the graphite spheres. Moormann emphasizes that these are inherent problems of pebble bed reactors (i.e. not just an AVR problem) and asks whether the pebble bed principle is feasible or justifiable at all. Moormann later contributed to the discovery of further irregularities and incidents in the AVR.

It was only discovered in 1999 that the AVR floor reflector on which the pebble rests broke during operation and that around a few hundred fuel assemblies got stuck in the crack that had formed or fell through as fragments. Most of these fuel elements could not be removed. There are no investigations into possible safety-related effects of this event.

A former (1964–1969) leading employee of the then construction consortium, Urban Cleve , who worked closely with the controversial LaRouche movement , denied incidents at the AVR and any dangers from the AVR from 2008. At conferences, including the LaRouche movement, claimed Cleve continue in the AVR reactor was even deliberately twice the GAU even or meltdown brought about without anything had happened. The then head of reactor technology at RWTH and FZJ, Allelein, also described AVR operation as sufficiently safe in the course of the Fukushima discussion in April 2011. The independent AVR expert group to investigate the AVR incidents did not follow Allelein and Cleve's positions, but confirmed serious hidden incidents and agreed with Moormann on almost all points.

An expert report from 1988 has been available to the NRW state government since 2011, which names serious safety deficiencies in pebble bed reactors - especially at the AVR. Above all, this includes the risk of prompt overcriticalities discussed above in the event of accidents with ingress of liquid water into the core in the case of a critical reactor, which can result in catastrophic destruction of the plant. The risk of prompt overcriticality has been confirmed by other authors. This safety report speaks of the Chernobyl syndrome of the pebble bed reactor and refers to the fact that the operating team made the AVR reactor nuclear critical for three days when liquid water flowed into the reactor during the accident in 1978 Reactor protection system manipulated inappropriately. Although this was a serious process, AVR GmbH was only warned by the NRW nuclear supervisory authority. The report also criticizes the inadequate shutdown system of the AVR: The shutdown rods installed outside the ball pile alone were not sufficient for shutdown, instead a minimum temperature of 130 ° C had to be maintained in the reactor core via an electrically heated auxiliary boiler, or several thousand fuel elements had to be maintained to prevent uncontrolled recriticality: On March 28, 1977, the AVR became unintentionally critical due to excessive cooling of the pebble with the reactor switched off, despite the shut-off rods being completely retracted; it was possible to return it to a controllable state without damage. According to the expert opinion, the AVR is completely inadequately protected against plane crashes and terrorist attacks. Presumably this safety report contributed significantly to the decision to shut down the reactor at the end of 1988.

Rainer Moormann's statements are predominantly viewed as destructive by proponents of pebble bed technology. Moormann received the 2011 Whistleblower Prize for his revelations, which were made against considerable opposition from supporters and in part by the FZJ .

AVR expert group

FZJ and AVR GmbH did not come to terms with the AVR past for a long time, despite the increasing evidence of concealed massive irregularities at the latest since the beginning of 2006. It was not until immediately after the Fukushima nuclear disaster that the FZJ and AVR GmbH set up an independent group of experts to review the history of the AVR and, in particular, to comment on the revelations by Moormann. A report was prepared in March 2014, which was publicly discussed with the authors on June 10, 2014.

The expert group notes, among other things, that

  • it has no information that would refute Moormann and Benecke's assessments of water ingress accidents in the AVR and their high risk potential; This also applies to Moormann's assessment that the AVR design accidents with water ingress could not be controlled because of the overheated core areas
  • overheated core areas were suspected as early as 1977, and criticized that this problem was only investigated ten years later
  • there is still no satisfactory explanation for the overheated areas in the AVR
  • the overheated areas in the AVR presumably led to the high contamination of the reactor; she considers the particularly strong increase around 1976 to be unexplained
  • illegal manipulations of the reactor protection system took place during the water ingress accident in 1978
  • not all reportable events were reported by AVR GmbH to the supervisory authority and reports often contained overly optimistic assessments
  • in particular, the classification of the real water ingress accident 1978 in the least dangerous category C was inappropriate; rather, a classification in category B, possibly even the highest category A, was appropriate
  • the allegedly favorable properties of the spherical fuel element for retaining fission products, which represent a crucial pillar of the HTR concept, have not been adequately proven, in particular with regard to diffusion-related permeability
  • the environmental monitoring of radioactivity - measured against the possibilities of the operating time - was inadequate
  • there is presumably no connection between AVR operation and leukemia cases around Jülich .

In a statement on the report, the FZJ regrets that there have been serious errors and omissions in the past, as well as inadequacies in compliance with the rules of good scientific practice. On May 14, 2014, FZJ announced that it would stop work on pebble bed reactors (except for disposal) as soon as possible and shut down the large-scale experiments that were still in progress.

The expert group's report essentially confirms the critics of pebble bed reactor technology. HTR supporters criticize the report as "defamatory".

Cases of leukemia among children in the Jülich region

Around 1990 there was a significant increase in leukemia cases in children in the neighboring towns of Titz and Niederzier. The FZJ ruled out radioactive emissions from FZJ and AVR as the cause. However, the processing of the AVR water ingress accident of 1978 and the AVR operation indicates that uncontrolled radioactive tritium emissions could have occurred on a large scale, especially via the groundwater (see accidents ). Before 1995, there were no analyzes for tritium either at the groundwater measuring points or in the waterworks, so that the tritium contamination of the population at that time is no longer clearly traceable.

In a report in 2010, the Düren district examined the potential health risks in relation to the operation of the AVR test reactor from a radiological point of view. In conclusion, the report states that there is no evidence of a connection between the operation of the AVR test reactor and health impairment. However, the report only covers the period from around 1995, i.e. not the aforementioned leukemia cluster.

The AVR expert group largely rules out a connection between leukemia cases and AVR operation. However, critics do not follow this, but point to a methodological error in the examinations of the expert group: The expert group has estimated the maximum conceivable dose during AVR operation on the basis of the most unfavorable measured values ​​and drew their conclusions from this. For tritium, which played an important role in the 1978 water ingress accident, this estimate used, due to the lack of older values ​​(see above), measured values ​​from 1997 in groundwater and drinking water, which are not representative of the period during which leukemia developed and the AVR water ingress accident and therefore a far too favorable picture could have generated. If this is accepted, a causal relationship between the leukemia cases and the tritium emissions could not yet be derived, but the exclusion of radioactive emissions from AVR / FZJ as the cause of the leukemia would falter.

Dismantling, disposal

The reactor vessel is not initially dismantled, as this is considered to be practically impossible for the next few decades due to its high level of contamination . In November 2008 it was instead filled with 500 cubic meters of lightweight aerated concrete in order to fix the highly radioactive graphite dust particles and to stabilize the container. Energiewerke Nord had already tried this procedure many times when securing ailing Russian nuclear submarines near Murmansk . Originally planned for 2011, in reality from November 2014 to May 2015, the 2100 ton container was lifted from its position by seven cranes and transported with a multi-wheel transport sledge for temporary storage via a few detours to a newly built hall 300 meters away. so that the soil radioactively contaminated with 90 Sr or the groundwater under the reactor can be cleaned. The delays in the dismantling resulted in around 1.3 million euros per month in personnel costs alone. After the aboveground structures have been removed, sheet piling must be rammed 17 m deep into the ground before the reactor foundation is demolished and the groundwater in the reactor area must then be pumped out to prevent the radioactive contamination from spreading during the demolition work on the foundation. A decision can only be made about the actual procedure for soil / groundwater purification if more detailed information about the contamination situation is available after the foundation has been demolished. Only then can a corresponding approval procedure be started. Previous measurements in less contaminated areas have already shown that the strontium concentration of 1200 Bq / kg is up to a factor of 2 above the safety threshold (clearance value for excavated soil according to the Radiation Protection Ordinance, since October 2011: 0.6 Bq (Sr) / g). In 2008, experts discussed the possibility of not cleaning the entire soil completely for cost reasons, but only the upper layers. For the deeper layers, only calculations should show that they do not pose a risk. It plays a role here that a sufficient number of analyzes to prove that strontium has been removed would be associated with unacceptably high costs. While this would be legally permissible, it would contradict AVR / EWN's public promises. In this context, the low intervention levels for strontium in water (3 Bq 90 Sr / l) and for soil surfaces according to the Radiation Protection Ordinance (2 Bq 90 Sr / kg soil) must also be taken into account. In the opinion of critics, the AVR site will remain a radioactive contaminated site in the long term, despite the renovation.

Another problem was the very strong radiation from the reactor vessel, which according to calculations will practically reach the permissible limit values ​​on the fence of the plant during the transport phase. Preliminary measurements on the container filled with concrete showed that the radiation could be up to a factor of 130 higher. More recent results show that the last-mentioned strong radiation was not emitted from the container, but from components outside the container. In January 2011, AVR GmbH applied for a change in the transport permit for the reactor vessel with the aim of being able to use a multi-wheel vehicle instead of an air-cushion sled. Since this could be controlled remotely and the transport time would be reduced, it is hoped that it will reduce radiation exposure. The federal government estimates the cost of the partial dismantling, which is originally to be completed by 2015, at more than 600 million euros. In 1988, it was assumed that only 39 million DM, which roughly corresponded to the operators' reserves for disposal. It soon became apparent, however, that the disposal costs would be considerably higher and would exceed the financial strength of the AVR owners and shareholders; in addition, because of the legal form of the AVR as a GmbH, the AVR shareholders could not have been forced to assume the costs through liability enforcement. The federal government (90%) and the state of North Rhine-Westphalia (10%) assumed the disposal costs in the first dismantling phase. During this period from 1988 to 2003, i.e. before the AVR was taken over by Energiewerke Nord, dismantling costs of EUR 200 million had already been incurred without any significant progress being made. These older costs are usually not included in current EWN cost statements, which has occasionally led to misinterpretations regarding the total costs. From 2003, when EWN took over the AVR, the assumption of costs was changed to 70% federal and 30% NRW. The dismantling costs will significantly exceed those of the Stade NPP , which had 40 times the output and generated around 100 times the amount of electricity: The Stade NPP, which was decommissioned in 2002, will be dismantled by 2023 at a cost of (as of 2017) 1 billion euros. Only after a further decay period of at least 60 years should the AVR container finally be dismantled by robots and transferred to a repository . The problem with regard to the final storage of the reactor vessel is the very high content of 14 C in the graphite and coal stone internals (half-life = 5730 years), as this would exhaust the total 14 C activity permitted in the Konrad repository by at least 75%. The source of 14 C is mainly nitrogen, which was mainly present as an impurity in the coal rock and was also used to shut down the reactor: Nitrogen reacts through (n, p) -reaction (neutron capture and proton release) with high yield to 14 C. A final disposal of the container in Konrad shaft is practically out of the question. The 14 C problem only became apparent in 2000 after sampling: the Jülich information on the AVR inventory based on invoices had previously underestimated the 14 C amount by a factor of 25. Critics see this as proof of insufficiently intensive and careful preoccupation of the FZJ with questions of disposal of pebble bed reactors. Bringing the dismantled AVR container (500 m³ without packaging) to the final repository planned in Germany for heat-generating waste would, according to preliminary estimates, at least fivefold the final storage costs compared to the Konrad mine. A separate repository for the AVR reactor container, based on the model of planned French repositories for 14 C nuclear waste , is therefore also being discussed . In addition, the FZJ with the support of the BMBF, as part of the CarboDISP project, checked with negative results whether the approved limit value for 14 C in the Konrad shaft (400 TBq) could still be increased subsequently. The costs from 2015 (2022) are not yet known.

AVR nuclear waste in the damaged Asse-II test repository

101 barrels with approx. 50,000 to 55,000 irradiated AVR graphite spheres without nuclear fuel (only the number of drums was documented, the total number of spheres contained in them was subsequently estimated by the FZJ in 2010) and 8 drums that contained, among other things, AVR fuel element spheres irradiated for test purposes in research reactors (Number of fuel element balls still unknown), were stored in the Asse test repository as early as 1973–1978 . The stored AVR graphite spheres contained far more tritium and long-life 14 C than was permitted in the Asse. However, Jülich did not correctly declare this when it was stored ; instead, it disposed of the graphite ball containers as low-level radioactive substances in the Asse. When the inadmissibly high radioactivity inventory was noticed from 2008 due to outgassing tritium, FZJ had to make late reports for the radioactivity disposed of in the Asse. This increased the known tritium inventory of the Asse by more than a factor of 10. FZJ justified this in 2010 with the fact that it was not yet possible to measure tritium and 14 C during storage . In the meantime, however, documents have become known that prove that Jülich had precise knowledge of its high activity inventory before the Asse emplacement and therefore possibly carried out deliberate and large-scale unauthorized storage in the Asse. In addition, there is a suspicion that broken AVR fuel elements could have been brought into the Asse, possibly as the content of the aforementioned 8 drums with medium-level waste. During the storage in the Asse, Jülich was noticed during random checks due to incorrectly declared barrels.

Since it was clear from 1974 that the originally planned reprocessing of the AVR fuel elements in the Jülich JUPITER plant would not be feasible, but on the other hand that there were insufficient storage facilities for the spent fuel elements, Jülich tried to achieve disposal through storage in the Asse . A storage permit was applied for on October 6, 1975, and on March 4, 1976, the permit from the Physikalisch-Technische Bundesanstalt and the Clausthal Higher Mining Office for the storage of 100,000 AVR fuel elements with a total activity of a maximum of 81,000 TBq in the Asse became legally binding June 1978 expired. A permit for a further 60,000 AVR fuel elements has been applied for. The spherical containers should be composed in such a way that, according to the legal situation at the time, they were at the upper limit of medium-level waste. Large-scale storage of the AVR fuel assemblies was only avoided at the time because the population around the Asse, under the leadership of the deputy district administrator of Wolfenbüttel , Reinhold Stoevesandt , defended themselves politically and legally, as well as through publicity campaigns. The storage would have multiplied the radioactive inventory in the Asse.

Further details on AVR nuclear waste in the Asse can be found in the results reports of the investigation committee of the Lower Saxony state parliament on Asse (2012).

AVR castors: interim storage and further procedure

Since 1993, around 290,000 spent fuel element balls have been stored in 152 Castor casks in an interim storage facility on the FZJ site. Its approval expired, as has long been predictable, in mid-2013, as the necessary safety evidence for an extension is difficult; In addition, the majority of the FZJ supervisory board feared that the continued presence of nuclear contaminated sites in the FZJ could damage its reputation. The research center therefore intended to transfer the Castor containers (by truck or train) to the Ahaus interim storage facility. From 2010 onwards, this led to massive protests throughout North Rhine-Westphalia. A citizens' initiative against these plans was also formed in Jülich . In March 2012 it became known that the permit for storage in Ahaus could not be granted in good time because the quality of the application documents from Jülich was insufficient. The FZJ decided to apply for an extension of the Jülich camp until 2016 [out of date] . In July 2012, the FZJ's plans to dispose of the 152 castors in the USA became public. The background to this is the willingness of the USA to take back nuclear fuel that is problematic from a proliferation point of view if it has been delivered from the USA. This is especially true for typically low-burned fuels from material test reactors , the spent fuel elements of which contain even larger amounts of highly enriched uranium. Given the relatively high burn-up of AVR fuel, however, it is questionable whether there is still a significant risk of proliferation and whether this argument is only used to justify an export of nuclear waste. This is also supported by the fact that the AVR - although the determination according to and in the classifications of the IAEA and BfS is not a research reactor, but a test NPP - has been referred to by the FZJ as a research reactor since 2012; The background is probably that, according to the EU directive, nuclear waste export is only permitted for research reactors, but not for test NPPs (except for reprocessing, which is not permitted for NPPs under German law). An expert report by the US proliferation authority that became known in 2015 denies, in contrast to FZJ information, a proliferation risk in the AVR castors and therefore sees no need to transfer the castors to the USA for reasons of proliferation. The low-burned fuel element balls from the THTR-300 , which are located in Ahaus , have an undoubtedly higher risk of proliferation . In November 2012, the FZJ's supervisory board also formally decided not to move the castors to Ahaus, which was planned until mid-2013, and to start planning a new interim storage facility in Jülich. The transport plans to the USA as an alternative are retained with high priority. The 152 castors contain almost all of the fuel element nuclear waste from AVR electricity generation (1.5 billion kWh); however, this electricity generation only barely corresponds to a current German daily requirement (2011). This underlines the extremely high generation of radioactive waste in pebble bed reactors. The Jülich Castorenlager was the only German interim storage facility that did not pass a stress test in 2013. Since the license for the interim storage facility expired on June 30, 2013, storage was initially tolerated due to temporary nuclear regulations issued by the Düsseldorf supervisory authority, whereby FZJ had to report monthly on the status of the work for the license. Attempts by FZJ to prove the safety of the interim storage facility were unsuccessful within a set deadline. In order to meet the minimum security requirements, the interim storage facility was provided with a massive concrete wall from the beginning of 2014 to protect against terrorist plane crashes. On July 2, 2014, the nuclear supervisory authority issued an evacuation order for the interim storage facility and refused a further toleration because a sufficiently safe state no longer appeared to be achievable in the medium term. This no longer complied with the law, which prompted the public prosecutor to start investigations against the FZJ on suspicion of culpably causing the storage of nuclear fuel without a permit. The FZJ had to submit a concept for the evacuation by September 30, 2014. The background to this is the potential soil liquefaction at the storage site due to earthquakes , which was insufficiently taken into account during construction . This FZJ concept was requested and published by the environmental movement through the Environmental Information Act . The FZJ detailed concept is criticized both by the environmental movement and by the expert from the supervisory authority as being ineffective. In particular, the critics see a drastic underestimation of the problems and risks of the proposed US export. Improvements are expected by the end of 2015. The FZJ detailed concept shows that the FZJ crane system for loading the castors, which is subject to a separate permit, was not kept up to date and therefore lost its permit at the end of 2013. Up until the end of November 2016, when the crane system was renovated, it was therefore impossible to remove the castors from the warehouse. Critics accuse the FZJ of “sloppiness” in dealing with nuclear fuel. On September 1, 2015, the ownership of the Castors changed: Together with parts of the nuclear sector, they were spun off from the FZJ into the newly founded "Jülich Society for Nuclear Plants" under the umbrella of the federally owned EWN.

The first results of an environmental impact assessment for a possibly new interim storage facility in Jülich became known in May 2014: After that, no obstacles are recognizable. This option is favored by the environmental movement.

If the USA option mentioned above does not apply, the following must be taken into account: The Castor casks are only approved as transport and intermediate storage casks with a useful life of around 40 years, not as final storage casks. Before final storage, the balls must be reloaded into a container suitable for final disposal. Because of their flammability and leachability, the spheres must also be conditioned prior to final storage, i.e. they must be brought into a shape suitable for final storage . The previously proposed embedding in concrete is no longer likely to meet the increased security requirements. That is why embedding in SiC ceramic was suggested. This conditioning must also be carried out for the 600,000 THTR fuel elements located in Ahaus, so that planning of a joint conditioning system for the entire fuel element waste from pebble-bed reactors is necessary. According to the BMU , the PKA (pilot conditioning system) built in Gorleben is also conceivable as a conditioning system for the spherical fuel elements , which is met with resistance from local citizens' initiatives . According to information from the BMBF , the USA is demanding around 450 million euros for the takeover of the AVR castors. In the USA there is growing opposition to taking over the AVR nuclear waste in South Carolina; US regulators have announced that they will only accept nuclear waste from non-commercial facilities.

The application for storage of the Jülich castors in Ahaus was resumed in 2014 in view of the unsuccessful export efforts, and the storage permit was granted at the end of 2016. A transport permit that has also been applied for is currently (March 2018) not yet available. According to press reports, the federal government and state of North Rhine-Westphalia have agreed to initially transport the Jülich castors to Ahaus in 152 individual transports by the end of 2020. It is not denied by the federal government that a later shipment to the USA, together with the THTR castors, can still take place. Funding for development work to ship the ball to the United States continues.

Atomic sphere affair

In April 2011, a small request from the Greens revealed that 2,285 radioactive fuel element balls had been lost. This led to considerable media coverage throughout Germany and became known as the "atomic ball affair". The NRW Science Minister Svenja Schulze suspected that these fuel element balls could also have been brought to the Asse test repository. However, this is no longer comprehensible, as the "stored quantities in the test repository are not known". It was also reported that no fuel elements were allowed to be stored in the Asse test repository, as it was only approved for the storage of low and medium level radioactive waste . However, the inadmissibility of the storage of AVR fuel elements in the Asse is a misjudgment, as explained in the Asse chapter .

The research center contradicted the allegations about missing fuel elements and assured that the inventory of fuel element balls was documented "down to the milligram". Harry Voigtsberger (SPD), Minister of Economics in the Kraft I cabinet , admitted that the state government had flawed communication and said: "For the state's nuclear supervision, it is crucial that no amount of fissile material is missing." In mid-July 2011, an investigative committee of the NRW- Landtag to clarify the questions about the AVR fuel elements that may have disappeared. The committee became aware of documents that prove that the casks in Jülich had been mixed up with AVR fuel assemblies and that random samples showed a different content of the fuel elements in the casks than declared. Furthermore, it became clear that there is no precise documentation on the whereabouts of a few thousand spent fuel elements that had been destroyed for experimental purposes or in the reactor. The number of fuel elements that could not be removed from the reactor is also only vaguely known (see accidents ). Both state ministries and representatives of the Federal Ministry of Research criticized the research center's negligent, "nonchalant" approach to documenting the balls , which ultimately led to uncertainty about the whereabouts of the balls. An internal AVR document examined by the committee on the accounting of the AVR and FZJ for the IAEA concludes: “The above statements (...) may give the impression that the fuel element detection at the AVR was a complete mess. It should be noted, however, that the AVR reactor was the first of its kind. "

Overall, the committee did not find any evidence that 2285 AVR fuel elements were brought into the Asse, but that the fuel elements were handled carelessly. Because of the early NRW state elections in 2012, the committee of inquiry ended without a final report. Since the essential aspects had been clarified, the opposition from the CDU and FDP, which had set up this committee, decided not to reinstate it in the new legislative period.

Significance for HTR development

The AVR was originally only intended as a test reactor, which should demonstrate the basic feasibility of pebble bed reactors. Since the larger THTR-300, designed as a prototype of a pebble bed reactor, failed spectacularly, the AVR is still marketed by proponents of HTR technology as an allegedly successful reference system for a pebble bed reactor. All current pebble bed reactor projects and concepts are therefore based in large parts on the AVR. From the point of view of the globular HTR proponents, the following applies: AVR is the synonym for plausible nuclear safety; it is the reference system for transparent safety technology for the next generation of nuclear power plants. Therefore, the clarification of the AVR history and the confirmation of some of the generic problems of pebble bed reactors suspected by critics by the AVR expert group is of great importance.

The Chinese HTR-PM , which is due to go into operation in 2018, is being advertised as a Generation 4 reactor , it is based in part on the AVR, but can only reach a maximum useful temperature of 750 ° C and is therefore unsuitable for high-temperature process heat applications. Critics call the HTR-PM a medium temperature reactor and do not see it as a generation 4 prototype.

Web links

Individual evidence

  1. cf. z. B. Jülich experimental power plant in December 1969 , spiegel.de, July 24, 2009
  2. Patent US2809931 : Neutronic reactor system. Applied on October 11, 1945 , published on October 15, 1957 , inventor: Farrington Daniels.
  3. spiegel.de April 27, 2014: Jülich report: operators are said to have covered up reactor breakdowns ; Aachen News ; Flying blind through a highly dangerous experiment
  4. B. Mittermaier, B. Rusinek: Leo Brandt (1908–1971) Engineer - Science Funder - Visionary Scientific conference on the 100th birthday of the North Rhine-Westphalian research politician and founder of the Jülich Research Center ( Memento from February 2, 2014 in the Internet Archive ) p. 20 ff
  5. U. Kirchner The High Temperature Reactor Campus Research Vol. 667 (1991)
  6. Will Jülich's reactor turn into a nuclear ruin? World on Sunday 9th July 1978
  7. a b c VDI-Society for Energy Technologies (Publ.), AVR-Experimental High-Temperature Reaktor - 21 years of successful operation for a future technology , VDI-Verlag GmbH, Düsseldorf 1990
  8. PowerPoint presentation - timeline 1956–2006: February 27, 1974 World record: The Jülich high-temperature reactor AVR reaches 950 ° C (PDF) fz-juelich.de. P. 15. Archived from the original on January 29, 2012. Retrieved January 26, 2014.
  9. J. Elder, M. Salazar: Decommissioning the UHTREX Reactor Facility at Los Alamos, New Mexico; Chapter 1.1 . osti.gov. August 1, 1992. Retrieved January 26, 2014.
  10. Schulten wants to save the coal. In 1980 the 'black gold' will turn into industrial gas with reactor heat. Westphalian News July 3, 1968
  11. Conversion of the AVR reactor into a process heating system: results of the preliminary planning. Internal report KFA Jülich (1985)
  12. a b c Heinsberger Nachrichten, November 26, 2008
  13. a b c d e Rainer Moormann: The Jülich atomic debacle March 8, 2014 pdf ( Memento of the original from March 11, 2014 in the Internet Archive ) Info: The archive link was automatically inserted and not yet checked. Please check the original and archive link according to the instructions and then remove this notice. @1@ 2Template: Webachiv / IABot / www.westcastor.de
  14. ↑ Expenses for the demolition of the Jülich nuclear reactor explode . vista verde news. June 24, 2002. Archived from the original on March 4, 2016. Info: The archive link was automatically inserted and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. Retrieved January 26, 2014. @1@ 2Template: Webachiv / IABot / www.vistaverde.de
  15. Demolition of the nuclear reactor in Jülich. ( Memento from April 15, 2013 in the web archive archive.today ) Süddeutsche Zeitung from February 15, 2003
  16. ^ German Atomic Forum e. V .: Annual Report 2008 - Time for Energy Responsibility . Berlin 2009, ISSN  1868-3630 . Page 32
  17. Rene Benden: The nuclear reactor is ready for the move. Aachener Nachrichten April 4th, 2014; Short version: https://www.aachener-nachrichten.de/lokales/juelich/avr-reaktor-vor-umzug-ins- Zwischenlager-1.798583
  18. Mark Hibbs, Decommissioning costs for German Pebble Bed Reactor escalating, NUCLEONICS WEEK, Vol. 43, no. 27, p. 7 (July 2002)
  19. a b E. Wahlen, J. Wahl, P. Pohl: Status of the AVR Decommissioning Project with Special Regard to the Inspection of the Core Cavity for Residual Fuel (PDF) wmsym.org. Retrieved January 28, 2014.
  20. a b Brochure high temperature reactors BBC / HRB publication no. D HRB 1033 87 D
  21. Safety revaluation of the AVR pebble bed reactor , Moormann, Rainer (2008) A safety re-evaluation of the AVR pebble bed reactor operational and Its Consequences for future HTR concepts . Reports from Forschungszentrum Jülich JUEL-4275, Forschungszentrum Jülich (ed.) (There PDF, English)
  22. Reportable events with activity taxes without exceeding limit values ( Memento from February 26, 2015 in the Internet Archive )
  23. a b Special incidents in nuclear power plants in the Federal Republic of Germany (PDF) bfs.de. P. 12. Archived from the original on January 23, 2012. Info: The archive link was automatically inserted and not yet checked. Please check the original and archive link according to the instructions and then remove this notice. Retrieved January 28, 2014. @1@ 2Template: Webachiv / IABot / www.bfs.de
  24. a b c d e Egon Ziermann, Günther Ivens: Final report on the power operation of the AVR experimental nuclear power plant, FZJ report Jül-3448 (1997)
  25. ^ MAGS Düsseldorf, Atomic Supervision: Dose rates in the AVR site and at the reactor building, reference number III A 4–8944.65 from January 23, 1975
  26. ^ Letter from AVR GmbH to MAGS / Atomic Supervision (Düsseldorf) of July 17, 1975, Az. H4-S5a4 Ku / Lö
  27. a b Andreas Langen: Give us the ball . kontext-wochenzeitung.de. December 2011. Archived from the original on February 26, 2015. Info: The archive link was automatically inserted and not yet checked. Please check the original and archive link according to the instructions and then remove this notice. Retrieved January 28, 2014. @1@ 2Template: Webachiv / IABot / old.kontext-wochenzeitung.de
  28. a b Andreas Langen: Radiant masterpiece . kontext-wochenzeitung.de. January 2012. Archived from the original on February 2, 2014. Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. Retrieved January 28, 2014. @1@ 2Template: Webachiv / IABot / old.kontext-wochenzeitung.de
  29. Summary report on reportable events 1977/1978 ( Memento from January 17, 2012 in the Internet Archive ) (PDF; 1.2 MB), Federal Ministry for Radiation Safety
  30. Report Safety-Related Experiences With The AVR Reactor KJ Krüger, GP Invens, Arbeitsgemeinschaft Versuchs-Reaktor GmbH
  31. Reiner Priggen : The almost nuclear disaster in the "inherently safe" reactor in Jülich (PDF; 382 kB)
  32. Publication Fission Product Transport and Source Terms in HTRs: Experience from AVR Pebble Bed Reactor (2008) Rainer Moormann, FZJ, Jülich
  33. a b c Special report of the NRW state government on AVR soil / groundwater contamination (2001)
  34. Frank Dohmen, Barbara Schmid: Dismantling of the Jülich reactor: Hot Meiler . In: Spiegel Online , July 24, 2009. Retrieved January 28, 2014. 
  35. Presentation Graphite Dust in AVR (PDF; 2.6 MB), Bärbel Schlögl, FZJ, Jülich
  36. http://www.solidaritaet.com/neuesol/2013/17/konferenz.htm
  37. The technology of high-temperature reactors, described by Dr.-Ing. Urban Cleve, Dortmund
  38. "The operation of the AVR was probably a unique success story" . In: New Solidarity . November 10, 2010. Retrieved January 28, 2014.
  39. Lecture U.Cleve at RWTH Aachen / Eisenhüttenkunde, celebratory colloquium for the 75th birthday of Prof. Gudenau, July 15, 2011. The text of the lecture can be found on the website of the controversial EIKE organization, which is considered spam in Wikipedia and therefore cannot be quoted is
  40. ^ WDR3 television, current hour, contributions to the AVR by Astrid Houben and Martin Herzog, April 6, April 7, April 8, 2011
  41. ARD Tagesthemen, April 8, 2011
  42. J.Benecke, P.Breitlohner, D. Maison, M.Reimann, E.Sailer: Review of nuclear facilities in NRW: Criticism of the safety devices and the safety concepts of the THTR-300 and the Jülich experimental reactor (AVR), expert opinion for the NRW state government , March (1988). The report was treated confidentially for a long time, but could be viewed at the end of 2011 in accordance with the Environmental Information Act at the nuclear supervisory authority in the NRW Ministry of Economics in Düsseldorf. It is now available under Archive Link ( Memento of the original from July 16, 2014 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. @1@ 2Template: Webachiv / IABot / www.westcastor.de
  43. J.Szabo et al .: Reactivity effects of water ingress in HTGRs - a review . In: Technical committee on reactivity transient accidents. Proc. of the first technical committee meeting organized by the IAEA and held in Vienna, November 17–20, 1987. Document IAEA-TC-610
  44. J.Szabo et al., Nuclear safety implications of water ingress accidents in HTGRs, Nuclear Society of Israel, Transactions 1987, IV-13 ff
  45. Note III C 4–8944 AVR – 3.12.1, MAGS, Düsseldorf, July 21, 1978. NRW nuclear supervision ( Memento of the original from April 6, 2014 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. @1@ 2Template: Webachiv / IABot / www.mweimh.nrw.de
  46. M. Taubner, Can truth be sin? Brand eins , May 2012 pp. 106-109.
  47. it caused Chancellor Merkel to withdraw the recently decided extension of the term , to a nuclear moratorium and to the permanent shutdown of eight of the 17 German nuclear reactors (" Atomausstieg ", " Energiewende ")
  48. AVR expert group ( Memento of the original from January 16, 2014 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. @1@ 2Template: Webachiv / IABot / www.fz-juelich.de
  49. The AVR experimental reactor - development, operation and accidents. Final report of the AVR expert group. C. Küpers, L. Hahn, V. Heintzel, L. Weil. April 1, 2014 (pdf)
  50. http://www.aachener-zeitung.de/lokales/juelich/juelicher-reaktor-es-gibt-noch-fragen-1.846072
  51. ^ Statement of the research center on the report of the AVR expert group. ( Memento of the original from April 26, 2014 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. April 26, 2014 @1@ 2Template: Webachiv / IABot / www.fz-juelich.de
  52. ^ Rene Benden: Research on HT reactors before the end. May 14, 2014 http://www.aachener-nachrichten.de/lokales/region/forschung-an-ht-reaktoren-vor-dem-aus-1.826886
  53. ^ A b Rainer Moormann, Jürgen Streich: Pebble bed reactors - status after publication of an independent expert study on the AVR Jülich. http://www.strahlentelex.de/Stx_14_664-665_S01-07.pdf
  54. U. Cleve: Letter to NRW Prime Minister Kraft (2014) kpkrause.de/wp-content/2014-05-02-Cleve-an-MP-Kraft.doc
  55. Jülich: 12 children with leukemia. http://www.focus.de/magazin/archiv/juelich-12-kinder-an-leukaemie-erkrankt_aid_142002.html April 5, 1993
  56. H. Kuni: A Cluster of Childhood Leukaemia in the Vicinity of the German Research Reactor Jülich (1998) http://staff-www.uni-marburg.de/~kunih/all-doc/juele.pdf
  57. District Düren - Health Department (2010): Potential health risks in the city and in the "old district" Jülich in relation to the operation of the nuclear research facility (AVR test reactor), fine dust emissions and electromagnetic fields http://www.kreis-dueren.de/gesundheit /pdf/gesundheitsrisiken_Bericht_Juelich.pdf
  58. Archive link ( Memento of the original from May 27, 2015 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. @1@ 2Template: Webachiv / IABot / www1.wdr.de
  59. a b c AVR experimental nuclear power plant Jülich Approval 7/16 AVR for the complete dismantling according to § 7 Abs. 3 Atomic Energy Act - Statement of the Radiation Protection Commission (9/10 December 2008)
  60. Federal Ministry of Education and Research : Response of the Federal Ministry to a request to a member of parliament ( memento of the original from September 15, 2011 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. (PDF; 42 kB) @1@ 2Template: Webachiv / IABot / oliver-krischer.eu
  61. Jülich: Dismantling the reactor is more expensive and takes longer . In: Aachener Nachrichten . September 15, 2012. Retrieved January 28, 2014.
  62. Decommissioning and dismantling of nuclear power plants and disposal of radioactive waste - questions about bearing costs and provisions of energy supply companies (PDF) bundestag.de. S. November 9, 2011. Retrieved January 29, 2014.
  63. Monika W. Florjan: Decontamination of nuclear graphite by thermal treatment . fz-juelich.de. Archived from the original on February 2, 2014. Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. Retrieved January 29, 2014. @1@ 2Template: Webachiv / IABot / juwel.fz-juelich.de
  64. W. von Lensa include: treatment and disposal of irradiated graphite and other carbon materials . kernenergie.de. Archived from the original on February 3, 2014. Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. Retrieved January 29, 2014. @1@ 2Template: Webachiv / IABot / www.kernenergie.de
  65. a b Copies of some accompanying notes for the stored AVR containers (PDF) auf passt.org. Archived from the original on February 1, 2014. Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. Retrieved January 29, 2014. @1@ 2Template: Webachiv / IABot / www.aufzüge.org
  66. Udo Leuschner: Energy Chronicle August 2008
  67. a b c AG Asse inventory - final report (PDF) bmbf.de. Pp. 19-20. August 31, 2010. Retrieved March 3, 2018.
  68. a b Information on illegal nuclear waste disposal at Forschungszentrum Jülich . bi-ahaus.de. Retrieved January 29, 2014.
  69. a b Johannes Nitschmann: The Jülich atomic spheres were counted "nonchalantly" . In: Aachener Nachrichten , February 10, 2012. Accessed January 29, 2014. 
  70. J. Wolf: Final storage of spent fuel elements from the AVR experimental nuclear power plant in the Asse salt mine, KFA report Jül-1163 (1975)
  71. H. Gerwin, W. Scherer: Criticality calculations on the problem of the final storage of AVR fuel elements in the Asse salt mine, KFA report Jül-1071 (1974)
  72. The "Jülich spheres", worn spherical fuel elements from an experimental reactor. Collection of articles on www.spurensuche-meinung-bilden.de, accessed on August 1, 2011 ( Memento of the original from July 26, 2014 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. (PDF; 741 kB) @1@ 2Template: Webachiv / IABot / www.spurensuche-meinung-bilden.de
  73. Final report of the parliamentary committee of inquiry into the Asse II nuclear waste storage facility (PDF) fraktion.gruene-niedersachsen.de. October 15, 2012. Retrieved January 29, 2014.
  74. René Benden, Christian Rein: Jülicher Castoren: Atomic waste in a state without a permit . In: Aachener Zeitung , December 16, 2011. Retrieved January 29, 2014. 
  75. a b westcastor.de ( Memento of the original from January 24, 2014 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. @1@ 2Template: Webachiv / IABot / www.westcastor.de
  76. ^ Information on the approval process for AVR fuel elements at Forschungszentrum Jülich . bfs.de. Archived from the original on February 2, 2014. Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. Retrieved January 29, 2014. @1@ 2Template: Webachiv / IABot / www.bfs.de
  77. René Benden: Nuclear waste II: Jülich castors remain in the interim storage facility for the time being . In: Aachener Nachrichten , May 16, 2012. Retrieved January 29, 2014. 
  78. Rainer Kellers: New option for Jülich nuclear waste - atomic balls should be shipped to the USA . WDR.de. July 9, 2012. Archived from the original on November 10, 2012. Retrieved January 29, 2014.
  79. Federal Office for Radiation Protection: Nuclear Power Plants in Germany - Notifiable Events since Commissioning, as of April 13 , 2015 ( Memento from April 25, 2015 in the Internet Archive )
  80. BfS: Research Reactors in Germany ( Memento of the original from April 19, 2014 in the Internet Archive ) Info: The archive link was automatically inserted and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. @1@ 2Template: Webachiv / IABot / www.bfs.de
  81. Directive 2011/70 / EURATOM of the Council of July 19, 2011 on a Community framework for the responsible and safe management of spent fuel and radioactive waste
  82. http://www.srswatch.org/uploads/2/7/5/8/27584045/doe_memo_on_no_proliferation_risk_of_avr_spent_fuel_august_1_2013.pdf
  83. René Benden: Castor containers stay in Jülich . Aachener-Nachrichten.de. November 15, 2012. Retrieved January 29, 2014.
  84. Jülich interim storage facility fails in the stress test. , Die Welt March 26, 2013
  85. Christian Rein, Volker Uerlings: The concrete mixers will soon be rolling to the Jülich interim storage facility . In: Aachener Nachrichten , December 18, 2013. Retrieved January 29, 2014. 
  86. http://www.aachener-zeitung.de/lokales/region/forschungszentrum-staatsanwaltschaft-ermittelt-gegen-mitarbeiter-1.1134683
  87. Archive link ( Memento of the original from July 14, 2014 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. @1@ 2Template: Webachiv / IABot / www.mweimh.nrw.de
  88. Detailed concept for the removal of the nuclear fuel from the AVR cask storage facility in Jülich. http://umweltfairaendern.de/wp-content/uploads/2014/12/Detailkonzept-Juelich.pdf
  89. http://www.aachener-zeitung.de/lokales/region/juelicher-castortransport-in-die-usa-faellt-durch-den-tuev-1.1094374
  90. http://www.klimaretter.info/politik/grund/18860-juelicher-reaktor-behaelter-auf-kurzreise
  91. http://www.aachener-zeitung.de/lokales/juelich/juelich/forschungszentrum-nicht-mehr-fuer-juelicher-atommuell-verektiven-1.1170435
  92. Archive link ( Memento of the original from July 14, 2014 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. @1@ 2Template: Webachiv / IABot / www.fz-juelich.de
  93. a b https://www.welt.de/politik/deutschland/article129923160/Helfen-die-USA-Deutschland-aus-der-Atommuell-Falle.html
  94. a b Atomic Balls: Transport to the USA illegal? ( Memento of the original from July 9, 2014 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. , WDR from July 8, 2014 @1@ 2Template: Webachiv / IABot / www1.wdr.de
  95. J. Knorr et al: SiC encapsulation of (V) HTR components and waste by laser beam joining of ceramics. Nuclear Engineering and Design 238 (2008) 3129-3135
  96. 2013 Difficult year of resistance . Citizens' initiative for environmental protection Lüchow-Dannenberg eV. January 1, 2013. Retrieved January 29, 2014.
  97. Jülich-Ahaus-Gorleben: a nuclear triangle? . January 6, 2012. Retrieved January 29, 2014.
  98. ^ "Spiegel": Disposal of radioactive waste from Jülich costs almost half a billion euros . ad-hoc-news.de. September 1, 2013. Retrieved January 29, 2014.
  99. https://www.aachener-zeitung.de/lokales/region/atommuell-wird-von-juelich-nach-ahaus- brought-1.1851699
  100. SPON : "NRW government measures 2285 fuel element balls"
  101. Answer of the state government to Small Question 583 of February 24, 2011 by MP Hans Christian Markert (Bündnis 90 / Die Grünen), printed matter 15/1429. (PDF; 99 kB) State Parliament of North Rhine-Westphalia, March 31, 2011, accessed on April 3, 2011 .
  102. ^ Heinsberger Nachrichten of April 5, 2011
  103. Kristian Frigelj: The strange game with the fuel elements balls. Welt Online, accessed April 15, 2011 .
  104. P. Pohl: Consideration of the accrued book deviations after completion of the previous fuel element and fuel bookkeeping. AVR memo E-6509. June 12, 2002, p. 13.
  105. Advances in energy technology; Monographs of the FZJ, Vol. 8 (1993) ISSN  0938-6505 , p. 251
  106. ^ First HTR-PM vessel head in place .