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02 kontakt Contents

1. Waste generation: Why there is a need for radioactive waste repositories in Germany. 04

2. Conditioning: How radioactive waste for the Konrad repository is packed and controlled. 10

3. Transport: How the waste gets to the Konrad repository and underground. 14

4. Disposal: How it is managed in Germany and abroad. 18

5. Interim storage: How the radioactive waste is currently stored. 22

6. History: How the Konrad ore deposit became a repository. 24

7. Suitability: Why the Konrad mine is suitable to host a repository. 26

8. Safety: How we fulfil our responsibility to man and environment. 30

9. Legal and social requirements: Why Konrad is a complex challenge. 36

10. Space for your notes. 40

11. Dialogue with Konrad. 42

Title: Area of Konrad 1.

03 1. Waste generation: Why there is a need for radioactive waste repositories in Germany.

04 Why waste does not equal waste. is both scientifically explored and accepted by the popu- Consumer waste, radioactive and chemical waste espe- lation to the greatest possible extent. No unacceptable Konrad terms cially differs in the emanating risk potential to man and burdens should be imposed on following generations environment. after emplacement operations in Konrad will have stop- ped and the repository will have been sealed. While normal consumer waste does usually not have major effects on health, residues from the chemical Germany is among the countries that will dispose of all industry must be treated in a special way. They are fre- types of radioactive waste in deep geological formations quently toxic and thus also hazardous. For many people in future. Thus maximum protection of man and envi- it is difficult to assess the potentially harmful effects ronment can be ensured. This decision was made on the of ionising radiation emanating from radioactive waste, basis of the population density, the climatic conditions since it cannot be perceived by man with any sense and the fact that suitable geological formations exist in organ. We cannot smell, see, taste or feel radioactivity, Germany. irrespective if it is weak or strong – it is nevertheless dangerous, often over longer periods of time. According to the “Joint Convention on the Safety of Spent Fuel Management and on the Safety of Radioactive Waste Management”, radioactive waste is to be pre- Why man and environment need to be protected. ferably disposed of in the country where it has been pro- Radioactive waste can be very hazardous. The emanating duced. Radioactive waste disposal is thus a national task. ionising radiation can cause permanent tissue and gene- tic material abnormalities and it can cause cancer. To achieve an enduring protection of man and environment What types of radioactive waste there are. from this ionising radiation, strict legal regulations in Waste does not equal waste. In Germany we distinguish terms of radioactive waste and its disposal are in effect between two types of radioactive waste: heat-genera- Toxic: Toxicity or harmfulness of a substance. in Germany. ting, high-level radioactive waste and waste with negli- Ionising: Feature of particle or electromagnetic radiation to remove one gible heat generation, also referred to as low-level and or several electrons from atoms or molecules, so that positively charged The federal government has decided to dispose of radi- intermediate-level radioactive waste. For safety reasons ions or molecule fragments remain. oactive waste in deep geological formations, i.e. deep one intends to dispose of both types in deep geological Radioactivity: Feature of instable atomic nuclei to spontaneously trans- underground, in order to isolate it from the biological formations. form releasing energy. The released energy is discharged in the form of cycle for as long as possible. The waste is to be perma- ionising radiation, namely high-energy particles and/or gamma radiation. nently disposed of free of maintenance on a site which In the Konrad repository, “radioactive waste with negli- gible heat generation” will be disposed of in future. The Negligible heat generation: Radionuclides cause an increase in tempe- rature due to the heat generating during the radioactive decay. In waste Left photo: Currently, about 96,000 cubic metres of radioactive waste with classification according to heat-generating waste and with negligible heat generation the increase in temperature in the sur- negligible heat generation are being stored in interim storage facilities. waste with negligible heat generation was especially rounding host rock must not exceed 3 degrees centigrade.

waste generation 05 Waste generation

made with respect to disposal. The international classi-

BWR SCHLESWIG-HOLSTEIN fication is “low-level and intermediate-level radioactive Greifswald/Rubenow PWR PWR PWR PWR PWR PWR 806 waste”, radioactivity itself being the key criterion here. Brunsbüttel Brokdorf 1.480 PWR Je 440 HAMBURG Stade MECKLENBURG-WESTERN BWR POMERANIA 672 Geesthacht Krümmel Unterweser PWR Where the radioactive waste originates from. PWR 1.402 15,0 5,0 Rheinsberg Radioactive, heat-generating waste is produced as BREMEN Munster Gorleben 70 1.410 spent fuel elements in nuclear power plants and in the BWR PWR LOWER SAXONY reprocessing of spent fuel elements. Waste with negli- Leese 252 1.400 BERLIN gible heat generation accrues in the decommissioning Lingen PWR 1,0 10,0 Grohnde Braunschweig and operation of nuclear power plants, in the nuclear Gronau Morsleben 1.430 Konrad industry, the nuclear research, very small volumes Ahaus Asse BRANDENBURG HTR are produced in the medical field or originate from BWR SAXONY- Hamm-Uentrop ANHALT 308 Würgassen the Federal Armed Forces. Among others, it contains 670 NORTH RHINE-WESTPHALIA contaminated material such as plant components, buil- HTR SAXONY ding rubble, tools and protective clothing, sludges or Rossendorf/ 15 23,0 HESSE Dresden suspensions. In the years to come, the amount of waste Jülich 10,0 THURINGIA resulting from the operation and decommissioning of Ebsdorfergrund Nuclear power station; PWR Figures: gross power output in MWe nuclear power plants will increase, as their dismantling Mülheim-Kärlich Research reactor; Figures: thermal power output in MW; Research reactors with constant thermal power output has been proceeding. 1.302 BWR of more than 50 kW RHINELAND- PALATINATE Hanau Kahl PWR Mitterteich Interim storage (in accordance with §6 AtG) Mainz 16 PWR PWR Approximate 290,000 cubic metres of radioactive waste Grafen- rheinfeld Nuclear fuel supply Biblis 1.345 Ellweiler 0,1 with negligible heat generation are to be expected until 1.225 1.300 Final repositories SAARLAND PWR 2050, approximate 63 percent of which would originate Obrigheim Disposal (e.g. conditioning plants, intermediate Elm- BWR PWR BAVARIA storage facilities) from nuclear power plants and the nuclear industry and Derlen 357 Philippsburg 37 percent from state institutions. Additionally, 7,500 926 1.468 PWR PWR BWR PWR State collection depots PWR FBR Karlsruhe Neckarwestheim cubic metres of radioactive waste will be produced in the 840 1.400 Isar Nuclear fuel reprocessing plants 912 1.485 57 21 44,0 eleven federal state collecting depots. The fraction of BWR BWR BWR Gundremmingen waste originating from medicine amounts to less than one Operational 1.344 1.344 250 percent. The costs for the management of the waste are BADEN-WÜRTTEMBERG In planning / under construction München/Garching/ borne according to the polluter pays principle. Accordingly Neuherberg 20,0 4,0 1,0 Closure phase or decommissioned

PWR = Pressurised Water Reactor BWR = Bolling Water Reactor Left photo: Survey of facilities according to nuclear law in Germany. Nuclear power station; Figures: gross power HTR = High Temperature Reactor (As at March, 2011) output in MWe FBR = Fast Breeder Reactor Research reactor; Figures: thermal power output in MW; Research Operational reactors with constant thermal power output of more than 50 kW Interim storage (in accordance with §6 AtG) In planning / under construction Closure phase or Nuclear fuel supply 06 decommissioned Final repositories

PWR = Pressurised Water Reactor Disposal (e.g. conditioning plants, intermediate storage facilities) BWR = Bolling Water Reactor HTR = High Temperature Reactor State collection depots FBR = Fast Breeder Reactor

Nuclear fuel reprocessing plants Forschungs- einrichtungen 44 %

Kerntechnische Industrie 7 %

Wiederaufarbeitung Karlsruhe 16 %

Kernkraftwerke, the utilities bear 63 percent of the costs. Thestillgelegt, remaining 12 % 37 the emplacement chamber walls (the “working face”). Konrad terms percent are at the expense of the public authorities.Landessammel- During radioactive decay energy is released. This can stellen 4 % davon Medizin result in an increase in temperature in the environ- (Lagerung The waste with negligible heat generationin Landessammel- represents ment. If this increase in temperature does not exceed 3 more than 90 percent of the total waste volumestellen) < 0,5– but % it degrees centigrade, the heat generation of the radioac- only contains 0.1 percent of the total radioactivityKernkraftwerke, of the tive waste is negligible, because the solidity of the rock in Betrieb, 17 % waste to be disposed of in Germany. is not affected. Low-level, intermediate-level, and high-level radioactive: The classi- fication of radioactive waste into low-level, intermediate-level and high- As other countries use different classifications of radio- level radioactive waste is a qualitative classification - to be able to better active waste (such as low-level, intermediate-level, and handle and process the radioactive waste. The allocation to the individual Nuclear power stations (EVU) 58 % high-level radioactive, containing short-lived and long- classes is determined by what measures need to be taken to protect man and environment from ionising radiation. Low-level radioactive waste, for State collection lived radionuclides), it is difficult to compare German and example, does not require shielding when being handled and transported depots 3 % of foreign radioactive waste volumes. which < 0,5 % since it only contains low activity. medical (storage in state collection Reprocessing: Application of chemical processes to separate uranium depots) Heat-generating radioactive waste has a higher activity. and plutonium from the radioactive waste in spent fuel after it has been Nuclear industry Accordingly, the temperatures originating during radio- used in reactors (e. g. in La Hague, France and Sellafield, Great Britain). 5 % active decay are higher, too. Contaminated: Polluted through radioactive substances. Publlic sector (incl. decommissioning of research reactors For this type of waste the Gorleben salt dome is being Suspension: Constant and stable distribution of solid matters in a liquid, and reactors in the the solid matters not being dissolved by the liquid. former GDR) 34 % investigated for its suitability to host a repository.

Utilities: Electric power companies.

CASTOR: CASTOR is the abbreviation of “cask for storage and transport How much radioactive waste there is in Germany and Prognosis of the volume of conditioned waste with negligible heat of radioactive material” and, in this sense, an internationally protected generation in 2050 (added), total volume: ca. 290,000 cubic metres. what part of it will be disposed of in Konrad. trade name. These casks are used for purposes such as the transport (As at March, 2011) According to the plan-approval decision of 2002 the and interim storage of spent fuel elements and high-level radioactive Konrad repository may take up maximal 303,000 cubic waste from the reprocessing of nuclear fuel.

metres of radioactive waste with negligible heat gene- Emplacement chamber: Mine opening with a cross section of about For comparison: One single CASTOR cask containing ration. In 2002, the storable waste volume was reduced 42 square metres (7 metres wide, 6 metres high) mined for radioactive heat-generating waste has a higher activity level than from 650,000 cubic metres originally applied for to waste disposal.

the entire permissible 303,000 cubic metres of radioac- 303,000 cubic metres. This was due to the fact that Plan-approval decision (licence): According to the administrative law tive waste that is to be disposed of in Konrad. a volume of around 290,000 cubic metres is being of the federation and the federal states, the plan-approval decision is a expected to be produced until 2050 according to the formal administrative procedure resulting in a binding official decision on a plan. A plan-approval decision replaces all other official decisions, In the Konrad repository, the criterion “negligible heat waste prognoses of the Federal Office for Radiation in particular approvals under public law, awards, permissions, authorisa- generation” refers to the increase in temperature of Protection. tions and approvals.

waste generation 07 Helium nucleus Electron Photon

Proton

Neutron The various forms of ionising radiation differ in their ranges: Alpha, beta and gamma radiation. Gamma rays Alpha radiation Beta radiation Gamma radiation have the highest penetration depth.

The Konrad repository has not been taken into operation What radioactive decay is and where it occurs. Beta radiation gets deeper into human skin layers and, so far, therefore waste with negligible heat generation Artificially generated radioactive substances and the depending on its intensity, can cause strong burns. In needs to be intermediately stored at present. At the end emanating radiation have entered into our lives through case of incorporation, beta-emitters such as stron- of 2009, it amounted to about 94,000 cubic metres in medicine, research, technology and the use of nuclear tium-90 or iodine-129 are deposited in various inner the form of conditioned waste. energy in reactors. organs where they cause high local radiation exposure.

Based on figures provided by the waste producers, the The effect of radiation, irrespective whether it is natural Gamma radiation has a high penetration performance Federal Office for Radiation Protection estimates that or artificial radiation, is the same – if we deal with the and affects inner organs, even in case of external radi- annually about 5,600 cubic metres of radioactive waste same type of radiation. Due to its ionising effect, dama- ation. This requires an effective shielding of the source, with negligible heat generation will add to that, which are ges can occur directly and immediately in the irradiated for example through lead. Neutron radiation takes a to be disposed of in the Konrad repository. The major organism. However, damages to the germ cells might special role as its risk potential strongly depends on its part of this waste will originate from the decommission­ occur, too, which would then affect our progeny. energy. Also, as a result of a so-called activation pro- ing of German nuclear power plants. cess, the irradiated matter itself can become radioactive. One differentiates between alpha, beta, gamma and neu- Shielding against neutron radiation is very complicated Until the expiry of the operating times of all nuclear tron radiation involving different risk potentials. and requires great effort. power plants, it is estimated that a total volume of annu- ally approximately 280 tons of heavy metal in the form Alpha radiation has a range of only some centimetres in Radioactive decay describes a process where in most of spent fuel elements, i.e. high-level radioactive waste, the air and is quasi harmless when outside the body. The cases an atomic nucleus gets from a less stable state into will accrue, Until 2050 this will amount to altogether alpha particles can penetrate the uppermost skin layers a more stable one. In this process particles (alpha and beta 21,700 tons, circa 15,000 tons of which will be suitable by only some micrometres, where they do no harm. In particles and neutrons) or photons (gamma radiation) can for direct disposal in Germany. Until 1 July 2005, about case of incorporation (taking up with food or through be emitted. This process occurs spontaneously, i.e. it can- 6,600 tons had been taken to reprocessing plants in inhaling), however, the damage inside the body can be not be influenced from the outside. As the atomic nucleus France and Great Britain and will finally be disposed of considerable. transforms into the nucleus of another nuclide in this in Germany. process, it is also referred to as nuclear transformation.

08 Frequently also the newly generated atomic nucleus is While the BfS has the role of operator and builder the DBE radioactive; thus we deal with “decay chains”. carries out the planning and construction of the Konrad Konrad terms repository as a public construction project. The DBE co- One feature of the radiation generated in nuclear trans- ordinates the construction progress and is responsible formation is that it can ionise matter, which may, for for the detailed planning. Mainly external companies are example, lead to permanent changes in irradiated tissue. commissioned with the technical works. It is the duty of On account of this effect it is termed “ionising radiation”. the DBE to inform the operator, e.g. about the develop- Conditioning: Production of waste packages through processing and/or ment of costs and the state of implementation. The BfS packaging of radioactive waste. Ionising radiation has been both part of nature since the manages the overall project, co-ordinating the numerous Reactor: Short term for nuclear reactor or also nuclear power plant. Earth’s genesis and a result of human activities. Meta- procedures with the competent licensing authorities.

phorically speaking, we are surrounded by radioactive This includes, for example, the Federal Ministry for the Incorporation: Taking up– in particular toxic or radioactive – substances substances and ionising radiation everywhere. Natural Environment, Nature Conservation and Nuclear Safety into the body. This can occur via the respiratory system (inhalation of gas radioactive nuclides such as uranium-238, uranium-235, (BMU), the Federal Railway Authority (EBA), the Lower or suspended particles) or via the skin (wounds, mucous membranes etc.) and by taking up something orally (ingestion). thorium-232 and potassium are found in the soils and Saxon Ministry for the Environment and Climate Protec-

rocks of the Earth’s crust. The major share of environ- tion (NMU), The Loxer Saxon Ministry of the Interior and Neutrons: Neutrons are heavy, electrically charged particles in the mental radiation exposure to each person in Germany is Sports (NMI), the Lower Saxon Ministry for Social Affairs, atoms’ nuclei. caused, for example, by the natural rare gas radon-222 Women, Family, Health and Integration (NMS), the Lan- Photons: All electromagnetic radiation – that does also include light – which is completely colourless, odourless and tasteless. desamt für Bergbau, Energie und Geologie (LBEG) and does not spread continuously but in the form of energy quants, so-called the city of Salzgitter. photons.

Who takes part in the erection of the repository. Nuclide: Different nuclides of an element (such as caesium-134, cae- sium-137) have the same number of protons but a different number According to § 9a paragraph 3 Atomic Energy Act the of neutrons. Thus, they have the same chemical but different physical overall responsibility for radioactive waste manage- characteristics. ment is with the federal government. Statutorily, the Radiation exposure: Effect of ionising radiation on the human body. Federal Office for Radiation Protection is responsible Whole-body exposure is the effect of ionising radiation on the whole “for establishing and operating federal facilities for the human body. Partial-body exposure is the effect of ionising radiation on safekeeping and disposal of radioactive waste.” Accor- a single body parts or organs. External radiation exposure is the expo- ding to § 9a paragraph 3 sentence 2 Atomic Energy Act sure to radiation sources outside the body, internal radiation exposure is the exposure to radiation sources inside the body. the federal government may commission a third party

as managerial aids with the erection of the necessary Atomic Energy Act (excerpt): facilities. In 1984 the federal government commissioned § 9a Utilization of residual radioactive material and disposal of radioac- the Deutsche Gesellschaft zum Bau und Betrieb von tive waste (3) […] the Federation has the task to establish facilities for the safekee- Endlagern für Abfallstoffe mbH (DBE) with planning and ping and disposal of radioactive waste. To fulfil its tasks it may make use erecting the Konrad repository. of third parties.

waste generation 09 2. Conditioning: How radioactive waste for the Konrad repository is packed and controlled.

10 What conditioning of waste means. (e.g. Studsvik, Sweden). Alternatively there are mobile Radioactive waste is treated and processed in a special waste treatment devices which can take up work at the Konrad terms way before it is accepted for disposal in a repository. The respective site of the waste producer. term for the treatment and/or packaging of the radioac- tive waste is conditioning. To safely package all types of How the packages of the waste are designed. radioactive waste with negligible heat generation and at When the waste has been processed into so-called bitu- the same time meet the waste acceptance requirements, men and synthetic products, solid matters, compacted various methods or conditioning facilities are available, waste or concentrates, it is packed in standardised con- depending on the consistency, size and quality of the tainers approved by the Federal Office for Radiation Pro- waste. tection. After it has been conditioned, the waste is placed in containers that are suitable for disposal and can, if the Liquid waste containers are also licensed for transport, be loaded onto is either dried, cemented, bituminised or vitrified. trains or freight vehicles in the next step.

Solid waste is crushed, dried, burnt, pyrolised, melted, compacted or cemented.

The responsibility for conditioning is in most cases with the waste producers themselves – i. e. the nuclear power plants, research institutions or companies of the nuclear industry. So-called small waste producers such as medi- cal laboratories deliver their waste to one of the eleven Bituminisation: Solidification of radioactive waste in a tar-like matrix federal state collecting depots, which commission special (bitumen matrix). installations with the conditioning of the waste. Pyrolise, To: Decomposition of chemical compounds through high tem- peratures. Strongly frequented conditioning plants that can be used by all waste producers are located e.g. in Karlsruhe, Compact, To: To grout under pressure, e. g. scrap press. Duisburg, Jülich, Krefeld or Braunschweig and abroad Federal state collecting depots: The federal states operate collecting depots where radioactive waste (except nuclear fuel) from industry and research and, to a small extent, from medicine, having accrued on their terrain is intermediately stored.

Left photo: A waste container is filled with concrete. Compacted waste: Solid radioactive waste pressed together under high Right photo: Cylindrical cast-iron containers are loaded. pressure, possibly in a metal cartridge or drum.

conditioning 11 Basically there are three types of containers. Cylindrical cast-iron containers controlled whether the waste acceptance requirements have – according to requirement – different dimensi- are complied with. This is done by the Federal Office Cylindrical concrete containers ons and wall thicknesses and are mostly used for the for Radiation Protection in collaboration with external from normal or heavy concrete are usually used for packaging of non-immobilised waste. The lid is bolted experts. The radioactive waste to be controlled may eit- immobilised waste. with the container body. her be waste that has already been conditioned or that still requires conditioning. Waste package quality control The containers are filled with a 200-litre or 400-litre Containers is performed in such a way that waste packages not in drum where the radioactive waste has been placed in are ashlar-formed, large-volume containers of steel plate, compliance with the waste acceptance requirements are – voids between drum and concrete container are subse- cast material or concrete provided with a wire mesh and recognised safely and are not delivered to the repository quently filled with concrete before the container is closed of which there are different designs, sizes and wall thick- in the first place. with a lid. nesses. With shortly 28 cubic metres the largest contai- ner can e.g. accommodate up to 28 200-litre drums. It Basically, there are two ways of carrying out waste can also be filled directly with unpackaged radioactive package quality control: waste. In case waste packages have not been conditioned accor- The waste producer can decide themselves for the form ding to today’s provisions, type and extent of the con- of packaging. It is essential that these packagings have trols depend on whether and how the documents make been approved for the respective waste type. clear that the waste acceptance requirements have been complied with. If experts consider it necessary they carry What controls the waste is subject to. out destructive or non-destructive random tests of these Safety is first priority – at any time in the emplacement waste packages. Depending on waste type, they combine process. Therefore, only waste packages in compliance in practice random samples and procedure tests (condi- with the waste acceptance requirements may be sto- tioning process). If one proceeds according to an appro- red in the Konrad repository. It has been set out in the ved schedule it is made sure that the entire waste has provisions of the waste acceptance requirements that been packaged in a way that is suitable for disposal and radioactive waste may only be available in a solid or that all repository-relevant data has been documented. solidified form, does neither rot nor ferment nor must it contain self-igniting or explosive components. The term As set out in today‘s provisions, a schedule stating how solidified means that e.g. liquids are solidified with the the waste has to be treated must be submitted already help of concrete before they are placed into containers. prior to conditioning. This schedule is evaluated and Within the scope of waste package quality control it is approved by the Federal Office for Radiation Protection. Thus it is made sure that the produced waste packages are in compliance with the waste acceptance require-

A drum containing low-level radioactive waste is closed. ments. Furthermore, during conditioning it is controlled

12 that the companies carrying out the conditioning actually work according to this schedule – the focus being espe- cially on the process flow and the documentation of the conditioning process.

The second procedure is preferred, as the waste is being processed and at the same time controlled. It reduces the dose rate of the staff.

Only after it has been made sure that the waste packages comply with the waste acceptance requirements, is the radioactive waste safely taken underground into the emplacement chambers. Emplacement chambers are horizontal mine openings constructed for storage.

Waste packages not complying with the waste accep- tance requirements do usually not get to the Konrad repository, since the narrow control system sorts them out beforehand. Should waste packages all the same be delivered to Konrad that are not suited for disposal, they are either rejected or kept in the buffer hall until the Federal Office for Radiation Protection has decided what will be done with them.

Low-level radioactive waste is burnt in an incineration plant.

conditioning 13 3. Transport: How the waste gets to the Konrad repository and underground.

14 Why transport to the Konrad repository is safe. Nevertheless, under the present rules one needs to make Radioactive waste transports to the Konrad repository sure that radiation exposure is minimised. This is crucial Konrad terms do not pose a risk, either to the population, the transport for standstill situations. Therefore, by taking structural, staff or the environment. According to a safety assess- technical or organisational measures, one needs to make ment carried out by Gesellschaft für Anlagen- und Reak- sure that no preventable radiation exposure can occur, torsicherheit (GRS) this applies to both normal transport even if people need to stay beside a transport vehicle for and transport accidents which cannot be ruled out. The a longer period of time. “Konrad Transport Study 2009” thus confirms calculati- ons carried out by the GRS as early as in 1991 on behalf of What infrastructure is used for transport. the Federal Environment Ministry (BMU) and the Federal Not only does the population regard the disposal of Office for Radiation Protection. radioactive waste in Konrad with some criticism but also the transport of waste packages to Salzgitter. However, Regarding the transport of the waste the calculati- provided consignments are properly handled, neither ons show that the additional radiation exposure for transport routes, traffic volume nor the packaging of local residents directly affected amounts to maximum the waste itself need to be cause for concern – a fact 0.02 millisievert per year. That is two percent of the valid that has been explained time and again by independent limit of 1 millisievert. With up to 0.15 millisievert the addi- professional opinions at a national and international tional exposure due to cosmic radiation during a return level. flight from Frankfurt to New York is clearly higher than the calculated maximum value due to the transports. The waste producers i.e. the nuclear power plants or the Also for the transport staff the radiation dose remains so nuclear industry are responsible for transporting the low that generally no additional monitoring or protection waste packages. As these sites generally are suitable for measures are required. rail transport, the Federal Office for Radiation Protection assumes that the bulk of waste will arrive by rail. Deli- Altogether the potential radiation exposure stated in very via inland waterway is not an option, as neither the the updated transport risk assessment is clearly below Konrad repository nor most of the waste producers own the values of the study carried out in 1991. The study is harbour facilities. available on the GRS homepage (www.grs.de) at “Publi- cations”. From today‘s point of view, the Federal Office for Radi- ation Protection’s experts estimate that on average not more than ten lorries and 20 wagons per week will arrive at the repository. Thus it will not be necessary to expand

Left photo: Per week an average of 20 wagons will arrive on the the road-rail network. Millisievert: Unit of the energy dose due to ionising radiation taken up repository premises. by the body.

transport 15 How the transports are secured. risk prevention officer. Furthermore, all transports are in such a way that even unforeseeable events such as Under the present rules only experts may be involved in marked with a sign as hazardous goods and “radioac- attacks, accidents or damage to the transport containers radioactive waste transporting. Prior to being charged tive”. The waste may solely be transported in officially can have disastrous effects. with the transport, all carriers prove their reliability approved containers that are secure from the radiation and expertise to the competent authorities and name a protection point of view and that have been designed Responsible for the transport licences according to the provisions of the Radiation Protection Ordinance and for all types of control are the Federal Railway Authority, the trade and industrial inspectorates and other federal authorities. The Federal Office for Radiation Protection then takes over the responsibility for compliance with the 3 waste acceptance requirements and transport safety on

13 2 the site of the Konrad repository.

How the emplacement process operates.

1 The wagons carrying the waste packages are delivered 12 to Beddingen freight terminal. From there they are transported to the Konrad repository site. After having 10 passed the drying plant, the wagon enter the reloading 7 hall; that is the place where the waste transported on 6 9 freight vehicles is accepted, too. In the next step all con- 11 14 tainers are reloaded onto a platform lorry with the help of 5 8 a bridge crane, are then taken to the radiation measuring 4 station, examined for their being suitable for disposal and transported to the shaft through the buffer tunnel.

Right photo: A container with low-level and intermediate-level radioactive waste is loaded onto a lorry.

Further information is available on the Internet at www.endlager-konrad.de. The planned above-ground facilities on the grounds of the repository: The employees in our information office, 1 Reloading hall 2 Konrad 2 winding tower and shaft building 3 Security building 4 Engine shed 5 Warehouse and workshop InfoKonrad, will also be pleased to 6 Friction winch 7 Substitute conveyor, fork lift truck and garage 8 Diesel pump 9 Staging area 10 Helicopter landing site provide you with further assistance. 11 Truck parking area 12 Buffer hall 13 Mine water transfer station 14 Shielding wall

16 Once cleared, the waste packages are then taken with debris, concrete and water) before the emplacement the conveyor cage to the underground area via the shaft chambers are finally provided with massive sealings in Konrad terms and subsequently to the bottom landing, where the waste order to protect the operating staff and the environ- is reloaded. From there the containers are taken with a ment from ionising radiation. Calculations show that transport vehicle via the gallery to the area where they about 17 transport units per shift can be emplaced under will be stored and are taken by a stacking vehicle into strict safety precautions. Thus altogether approximately the emplacement chambers, where they are stacked in 4,000 transport units containing radioactive waste with their final positions. Residual cavities between the waste negligible heat generation can be emplaced annually in packages are backfilled with thick matter (consisting of one-shift operation.

Radiation Protection Ordinance: The Radiation Protection Ordinance (StrlSchV) is part of the German nuclear law. It was first passed in 1976 and has since been adapted several times to the state of the art of sci- ence.

Bottom landing: Transition zone from shaft to mine.

Debris: Crushed material from the iron ore horizon.

transport 17 4. Disposal: How it is managed in Germany and abroad.

18 What the term repository means. 1.5 x 1017 becquerel alpha-emitters may be stored in the The term repository comprises the final emplacement of Konrad repository. What was disposed of in the Asse mine Konrad terms radioactive waste. According to the International Ato- and in the ERAM is depicted in the following. mic Energy Agency’s (IAEA) definition, repositories are nuclear facilities where radioactive waste is emplaced ERAM: a former potash and rock salt mine that was licen- to for the purpose of disposal without the intention sed as a repository according to GDR nuclear law and of retrieving it. One differentiates between reposito- was taken into operation in 1971. After reunification, the ries near the surface and those in the deep geological nuclear licence of 1986 granted by the GDR continued underground. Near-surface repositories are located just to be effective for ten years according to § 57a Atomic a few metres below the Earth’s surface. Here low-level Energy Act. Initially large waste volumes continued to be radioactive waste containing radionuclides with short emplaced in the ERAM until emplacement operation was half-lives is stored. Repositories in deep geological for- preliminarily banned by court order. For safety reasons, mations (such as the Konrad repository), however, are the Federal Office for Radiation Protection stopped the located several hundred metres below the Earth’s sur- emplacement of radioactive waste for good in 2001. The face. The waste is isolated from the biosphere for long decommissioning of the facility is currently being prepared Half-life: Time interval in which the respective acitivity of a radioactive periods of time. in a nuclear plan-approval procedure with public partici- nuclide reduces to 50 %. pation. Altogether approximately 36,800 cubic metres of Germany has decided in favour of maintenance-free low-level and intermediate-level radioactive waste with a Biosphere: Entirety of the parts of the Earth populated by creatures. radioactive waste disposal in deep geological formations. total activity of 3.8 x 1014 becquerel was disposed of in the 1018: is a one with 18 nulls, i. e. one trillion (AE: one quintillion). Corre- The protective shielding of the layers of earth and the ERAM between 1971 and 1998. spondingly, 1017 is a one with 17 zeros prevention of abusive (re-)use played an important role in the decision-making process. Atomic Energy Act (excerpt): § 1 Purpose of the Act Which other repositories exist in Germany. The purpose of this Act is Apart from Konrad there are two other facilities in Ger- 1. to phase out the use of nuclear energy for the commercial generation of electricity in controlled manner, and to ensure on-going operation many where low-level and intermediate-level radioac- up until the date of discontinuation, tive waste has been stored: the Morsleben repository 2. to protect life, health and property against the hazards of nuclear for radioactive waste (ERAM) and the Asse repository energy and the detrimental effects of ionising radiation and to near Wolfenbüttel. According to the plan–approval deci- provide compensation for damage caused by nuclear energy or sion, radioactive waste with a total activity of maximum ionising radiation, 3. to prevent danger to the internal or external security of the Federal 5.0 x 1018 becquerel beta and gamma emitters as well as republic of Germany from the utilisation or release of nuclear energy or ionising radiation, Left photo: Vehicles underground. 4. to enable the Federal Republic of Germany to meet its international Right photo: Repository sites and projects in Germany. obligations in the field of nuclear energy and radiation protection.

disposal 19 Max. length 800 metres

Max. length 800 metres Container disposal Max. length 800 metres Return air feasible to recover the radioactive waste. This can only collection drift be achieved with considerable effort, however. Depen- Construction of a stowage wall Max. length 800 metres Drum disposal Stacking vehicleUnloading area ding on the time of recovery it is questionable whether 10 Stowage (sludge) min. metres it would be feasible to recover waste packages that are 3 2 still intact and manageable. Prerequisite for a safe dis- Stacking vehicle Max. length 800 metres 1 posal is the exact exploration of the repository site, its Stowed storage cavity (sludge) Transport vehicle 1 Escape road 2 Stowage transporter geological and especially hydro-geological conditions and 3 Hose manipulator vehicle the performance of site-specific assessments in terms Gravity stowing (sludge) of operational safety and long-term safety as they have Disposition transport roadway been performed for the Konrad repository.

Schematic diagram of the different steps How other countries dispose of radioactive waste. of emplacement into the emplacement Currently, repositories for low-level and intermediate- chambers. Asse mine: a for- level radioactive waste are in operation in 19 out of the mer salt mine that was 41 countries using nuclear energy. In most cases, operated on behalf of the fede- waste containing radionuclides with short half-lives is ration as federal research mine accor- emplaced in chambers near the surface in depths of up to ding to Mining Law by Gesellschaft für Strahlen- und commercially mined for a long time, so that both mines 300 metres, where it is then monitored for around Umweltforschung (today: Helmholtz Zentrum München contain a large number of cavities and are thus instable 30 years. During this time the use of the premises is – Deutsches Forschungszentrum für Gesundheit und at long sight. You will find more information on the repo- restricted. That is different with the Konrad repository, Umwelt GmbH). Approximately 46,300 cubic metres of sitories Asse and Morsleben on the BfS homepage at where the radioactive waste is stored in a depth of low-level and intermediate-level radioactive waste was www.bfs.de and www.endlager-asse.de. 800 metres. There will be no connection between the radi- disposed of in the Asse mine between 1967 and 1978. oactive waste and the biosphere. It also minimises the risk The total activity was 3.1 x 1015 becquerel. Licences What “non-retrievable disposal” means. of misuse for military or terrorist purposes. for this facility were granted according to Mining Law After the Konrad repository has been backfilled and in connection with the Radiation Protection Ordinance. sealed it will no longer be possible to access the radio- World-wide, high-level radioactive waste containing long- Since 1 January, 2009, the Federal Office for Radiation active waste immediately. This is to relieve future gene- lived radionuclides is to be disposed of in deep geological Protection (BfS) has been responsible for the operation rations from the burden of being forced to act. As our formations. In Finland and Sweden, corresponding reposi- of the Asse mine as a repository according to Atomic generation is the one using nuclear energy, it is also our tories for high-level radioactive waste are in the concrete Energy Act. generation’s task to ensure the ultimate disposal of the planning stage. accruing radioactive waste. Due to their geological conditions and their history, the Morsleben and Asse repositories do not compare with Basically, however, even if the waste has been disposed the Konrad repository. In Morsleben and in Asse salt was of without the option of retrieval, it is still technically

20 Konrad Shaft 1 Konrad Shaft 2

Up to 400-m-thick layer of different clays as natural geological barrier.

Iron ore horizon (host rock)

Old working chambers which are not Storage spaces to be used for disposal.

Model of the deep geological underground in the area of the Konrad repository.

disposal 21 5. Interim storage: How the radioactive waste is currently stored.

22 What interim storage means. What capacities there are for interim storage. Approximately 96,000 cubic metres of radioactive waste Altogether circa 400,000 cubic metres of radioactive Konrad terms with negligible heat generation that has been conditioned waste with negligible heat generation could be stored inter- and packed and approximately 600 cubic metres of heat- mediately in Germany. That is the capacity provided by generating waste (as at March 2011) are currently stored the interim storage facilities of the nuclear power plants, above ground. large research institutions, federal state collecting depots, and the North Interim Storage Facility. Until 2050 appro- According to the polluter pays principle, the nuclear ximately 290,000 cubic metres of conditioned radioactive power plant operators are obliged to store the major waste is anticipated. Bottlenecks could occur because part of this waste intermediately at the place where it some interim storage facilities may only be used by certain has been produced or in central interim storage facilities, waste producers or as a result of the extension of nuclear until it is disposed of in a repository. The same applies to power plant operating times. large research institutions. Waste from nuclear research, industry and medicine can be delivered for interim sto- rage to eleven federal state collecting depots in Germany (cf. survey map on page 6).

Until 30 June 2005, spent fuel elements from the operation of nuclear power plants were either taken to France (La Hague) or Great Britain (Sellafield) for repro- cessing or intermediately stored in the Gorleben and Ahaus interim storage facilities and in the Interim Sto- rage Facility North (Greifswald and Rheinsberg nuclear power plants). Since 1 July 2005, there has been a ban on delivering waste to reprocessing plants abroad. The ban is based on the Atomic Energy Act. To avoid trans- ports and for burden-sharing spent fuel elements have been stored intermediately on the nuclear power plant sites since. Federal state collecting depots (excerpt from the Atomic Energy Act): § 9a Utilisation of residual radioactive material and disposal of radioactive waste (3) The federal states shall establish state collecting facilities for the interim storage of the radioactive waste originating in their territories, Left photo: Low-level and intermediate-level radioactive waste is stored and the Federation shall establish installations for the safekeeping and in the interim storage facility in Karlsruhe. disposal of radioactive waste. […]

interim storage 23 6. History: How the Konrad ore deposit became a repository.

24 How the Konrad mine was discovered. In 2002, the Lower Saxon Environment Ministry granted In the thirties of the last century, a larger iron ore deposit the plan-approval decision (licence). Konrad terms was discovered near Salzgitter in the process of drilling for petroleum. However, not until 1957 did Salzgitter Erzberg- In 2007, more than three decades after the first pre-exa- bau AG initiate the sinking of shaft Konrad 1; shaft Konrad minations and five years after the plan-approval decision, 2 was sunk in 1960. Both shafts were connected under- it was confirmed by the superior court. The Federal Admi- ground in January 1963. From 1965 iron ore was mined nistrative Court in Leipzig rejected a complaint against and altogether 6.7 million tons of ore were won until 1976. the non-admission of the revision to the decisions of the Then Salzgitter AG stopped ore mining because it proved Lüneburg Higher Administrative Court. One could start to be unprofitable. implementing the plan.

As it was foreseeable that the mine had to be decommis- During court proceedings all further plans were stopped Sinking: Construction of a vertical mine opening such as shaft or bore sioned and because of the political and public pressure in order not to make any prior commitments and to get hole with different procedures such as blasting or drilling. increasing, Salzgitter AG searched for other options than planning safety by the court decisions. After the Federal Plan-approval procedure (excerpt from the Atomic Energy Act § 9b): the intended closure. For that reason and in knowledge of Administrative Court had made its decision in 2007, (1) The erection and operation of the federal installations referred to in the favourable geological situation of the mine, the works more than 500 collateral clauses contained in the plan- § 9a, paragraph 3 as well as any major alteration of such installations or council suggested to the Federal Environment Ministry to approval decision and the new legal and technical regu- their operation shall be subject to a plan approval procedure. […] investigate if Konrad was suitable for hosting a repository. lations (such as on energy-efficient construction) needed Physikalisch-Technische Bundesanstalt (PTB): Federal Institute of As early as in 1975, Gesellschaft für Strahlen- und Umwelt- to be integrated in the planning. Options for informing the Science and Metrology: provides scientific-technical services and is in forschung (today: Helmholtz Zentrum München – German public were not yet provided for in the seventies and had the portfolio of the Federal Ministry of Economy and Technology. The two Research Center for Environmental Health) therefore inve- to be included in the planning. Modern concepts on plant PTB top locations are in Brunswick and Berlin. stigated the mine for its suitability as underground deposit security were proposed by the BfS but not accepted by for radioactive waste. the responsible federal state authorities. Cost planning and schedules for the erection of the repository that had The explorations showed that from the geo-scientific been developed in the 1970ies and 1980ies were based point of view, Konrad was basically suitable as a repo- on unrealistic assumptions and proved unsustainable. sitory. In 1982, after the explorations had concluded, an Regulatory competences that had been taken as a basis application for the initiation of a plan-approval proce- in the 1980ies are considered different today. According dure was filed by Physikalisch-Technische Bundesanstalt to the present state of knowledge it will not be possible (PTB), predecessor of the Federal Office for Radiation to finish the repository before 2019. Protection in terms of disposal.

Left photo: Sinking of shaft Konrad 1 in 1958. Right photo: Konrad 2 sinking trestle.

history 25 7. Suitability: Why the Konrad mine is suitable to host a repository.

26 How Konrad was scientifically investigated. On the basis of the scientific assessment, the Konrad repo- The comprehensive licensing procedure including numerous sitory for radioactive waste with negligible heat generation Konrad terms examinations and site-specific safety assessments shows: was already licensed in 2002. Konrad is suitable to host a repository for radioactive waste with negligible heat generation. The former iron ore Why Konrad qualifies as repository. mine features a favourable geological situation. Of particular importance to the repository site is the overall geological situation that ensures that the waste Between 1975 and 1982, Gesellschaft für Strahlen- und is isolated for as long as possible in order to protect man Umweltforschung carried out comprehensive analyses and and environment. The ore deposits in the Konrad mine that examinations on the geology, hydrology, rock mechanics, will be used as host rock are situated 800 to 1,300 metres radiology and safety of the repository. After the exami- under the Earth’s surface. The overlying cover which is up nations had concluded, Physikalisch-Technische Bundes- to 400 metres thick and consists of different clay stones Hydrology: Science dealing with water. anstalt (PTB) filed the application for plan-approval and forms a natural barrier against the groundwater near the Radiology: Science dealing with radiation and its medical, especially carried out supplementing examinations on the structure surface and the Salzgitter branch channel. Thus waste can diagnostic and therapeutic application. and condition of the iron ore deposit (host rock) and of the already be emplaced in this depth. The 800-metre level is rock layers overlying and underlying the iron ore deposit, as safe as the 1,300-metre level. In terms of the isolating Host rock: Rock where the radioactive waste is emplaced. on the large-area geology and the hydro-geological condi- rock zone, Konrad is in compliance with the requirements Quaternary: The youngest period of the Earth‘s history covering the tions in the overburden. of the AkEnd. This is the part of the geological barriers last 1.8 million years. which, given a normal development of the repository and Apart from this, the analyses dealt with water examinations in combination with technical and geotechnical barriers, Cretaceous: Period of the Earth‘s history; between about 142 until 65 million years ago. of the aquifers of the Quaternary, Cretaceous and Jurassic must ensure the enclosure of the waste over the deman-

as well as with the hydrological conditions. Furthermore, ded period of isolation of one million years. Jurassic: Period of the Earth‘s history; between about 200 until the features of the rocks that are to serve as a barrier 142 million years ago. against the dispersion of radionuclides were examined The Konrad mine was used as an iron ore mine for a Radionuclide: Instable atom nucleus spontaneously decaying without with respect to permeability and sorption behaviour, the relatively short time, therefore the rock does not have extraneous impact when exposed to radiation. More than 1,200 natural rock-mechanic conditions in the surroundings of chambers, so many cavities. No old mine openings will be used for and artificial radionuclides are known. galleries and the entire mine, and the repository’s stabi- storage of the waste but new chambers will be mined lity against earthquake impacts. Physikalisch-Technische instead. Therefore and due to the rock characteristics, Sorption: Taking up of a gase or dissolved substance by another solid or liquid substance. Bundesanstalt (PTB) submitted the results to the highest stability problems as they exist in some other older

Lower Saxon authority. mines (ERAM and Asse) can be ruled out. Isolating rock zone: Part of the geological barriers that must ensure the isolation of the waste for the period of isolation for the expected After the repository has been closed it will take appro- development of the repository, in conjunction with technical and geo- technical barriers. ximately 2,000 years until the remaining cavities in the

Left photo: Vehicle repairs are carried out underground. mine will be filled with so-called formation water from the Cavity: The amount of cavities in a mine is relevant to the stability.

suitability 27 28 surrounding rock. In 2009 the inflow of brine amounted Where exactly the radioactive waste will be stored. to altogether around 6,000 cubic metres. Around 3,000 Two emplacement fields are planned for the Konrad Konrad terms cubic metres of the formation water originated from the repository. When emplacement operations start only cavities or galleries underground, respectively. The other a partial field situated near the Konrad 2 shaft will be 3,000 cubic metres of brine originated from certain geo- driven completely. There will be room for 63,000 cubic logical layers shaft tube 2 cuts through. The underground metres of radioactive waste. 60 percent of the field will inflow of formation water is continuously monitored and be filled with waste packages, residual cavities will be the water is collected in water tanks and pump swamps in backfilled with a special type of concrete and then be the galleries. Part of this water is used by the miners for sealed. If necessary, additional emplacement chambers dust reduction and track construction underground. The will be driven. The radioactive waste’s exact position in rest is taken above ground. the respective emplacement fields will be documented.

There is no direct natural hydraulic connection between the uppermost groundwater storey and the radioactive waste to be stored in future. Thus the repository area – as opposed to the Asse mine – is not in contact with surface water. This is taken care of by a 400-metres thick layer of clay covering large areas of the repository. For more infor- mation click www.endlager-konrad.de.

Why Konrad is earthquake-safe. The Konrad repository is situated in an area which is Formation water: Aqueous solution stored in rock layers originating from the time the rock layers developed. The water was enclosed very calm in terms of tectonics. No change of tectonic during the sedimentation in fine pores and clefts in the rock. behaviour is to be anticipated for the next millenia. Nevertheless, all buildings, technical and electrotechni- Adhesive anchor: Prevents that larger pieces of rock break and drop into the cavities of the mine. They work through a two-component cal equipment above ground and underground and the adhesive. entire Konrad mine have been designed to be earth- quake-proof according to the state of the art of science and technology. Further information is available on the Internet at www.endlager-konrad.de. The employees in our information office, InfoKonrad, will also be pleased to Left photo: Placing of adhesive anchors to prepare the emplacement provide you with further assistance. gallery.

suitability 29 8. Safety: How we comply with our responsibility to man and environment.

30 How population and staff are protected. What health risks due to ionising radiation exist. The following applies to the protection of the population: To be able to evaluate health risks due to ionising radi- Konrad terms Being the operator, the Federal Office for Radiation Pro- ation, radiation-exposed population groups – such as tection must prove that the limits for the population and survivors from Hiroshima and Nagasaki, victims of the the staff set out in the provisions of the Radiation Pro- Chernobyl reactor disaster, or staff groups of facilities tection Ordinance are complied with. For discharges and under nuclear law – were examined scientifically. These direct radiation from repository operation the limit value analyses have clearly shown the devastating effects is 1 millisievert per year. That is about half of the natu- ionising radiation can have on the human organism. ral radiation exposure occurring in Germany. This value However, the effect of ionising radiation on man essen- must not be exceeded by the operation of the Konrad tially depends on the intensity and duration of exposure. repository. Experiences from comparable facilities (such High exposures such as occurred as a consequence of as the Asse mine) show that these limits are clearly fallen the disasters in Chernobyl, Hiroshima and Nagasaki, are below in reality. associated with a higher cancer risk, lower ones with a correspondingly lower risk. Today, science assumes that To assess the radiation exposure to the repository staff there is no threshold below which there is no additional the most unfavourable conditions were taken as a basis, cancer risk. among others the dose rate of 2 millisievert per hour at the surface of the packages permitted according to traf- As consequently a risk of disease emanates from each fic law, which will not occur in reality. exposure to radiation, the limits set out in the Radiation Protection Ordinance are to ensure that this risk to the For individual workplaces relatively high radiation expo- population is low. Dose limits are frequently regarded sures were calculated. Therefore, collateral clauses were as a partition line between “dangerous” and “harm- decreed by the licensing authority whose objective is to less” radiation exposure. If the limit is exceeded, this minimise the radiation exposure to the operating staff. exposure is associated with a radiological risk to the Apart from that, the radiation protection concept for individual that has been classified by the legislator as Konrad provides for a continuous optimisation of radia- not being acceptable. A linear dose-effect relation is tion protection during the operation process on the basis assumed, i.e. also dose levels below the limits (so-called of experiences gained. LNT hypothesis) can lead to diseases. This relation is the reason for the law of minimum set out in the Radi- ation Protection Ordinance, which commits the opera- tor of a facility to keeping each radiation exposure or radioactive pollution of man and environment as low

Left photo: Also after the repository has been taken into operation it as possible, even below the limits. This is to be done by will be safely possible to take a bath in the Salzgittersee. observing the state of the art of science and technology Surface dose rate: Highest dose rate at the outer surface.

safety 31 and taking into account all circumstances of the indivi- (age < 1 year), the effective dose due to the sum of for in detail in normal operation. The listed controls are dual case. discharges is 0.19 millisievert per year. Straight at the carried out by the operator and surveyed by an indepen- fence of the facility the potential radiation exposure dent measuring institution. Only by this combination – limits and minimisation mea- due to direct radiation is below 0.6 millisievert per sures – is an appropriate radiation protection ensured. year. This calculation was also carried out with the An additional prerequisite for the licensing of the Konrad On account of this combination the risk of disease to the maximum values. Even at the most unfavourable place repository was to prove according to water protection population and the staff can be considered sufficiently the effective dose limit of 1 millisievert per year set out laws that there will be no damaging pollution as a result low. in the provisions of the Radiation Protection Ordinance of the repository operation. is thus kept. How much additional radiation emanates from Konrad. It is the declared aim of the Federal Office for Radiation During the operation of the repository, the maximum How the vicinity of the Konrad repository is monitored. Protection radiation exposure due to the discharge of radioac- According to § 48 of the Radiation Protection Ordinance apart from complying with the licensed discharge tive substances with waste water and exhaust air is the discharges from a repository and the vicinity of the levels 0.09 millisievert per year (effective dose) for an adult. repository need to be monitored radiologically. How to to keep the unavoidable discharges and the associa- For the age group with the highest exposure, the infant proceed in this case has been set out in the Directive ted radiation exposures as low as possible, also below on Emission and Immission Monitoring of the Facilities the legal limits and the licensed discharge values. according to Nuclear Law (REI). Exposure route Exposure to radiation and threshold values What controls there are already before emplacement according to the Radiation Protection Ordinance When the Konrad repository will be taken into operation operations start. (StrlSchV) in millisieverts per year all discharges will be measured and it will then be con- Already three years before the Konrad repository is Infant Adult Threshold trolled whether they are below the permissible discharge taken into operation the local dose rate and the activity A age < 1 year old age > 17 years old value volumes. This is e.g. done by taking representative of samples from the vicinity are determined according Exhaust air (§ 47) 0.05 0.028 0.3 samples from the waste water. Following laboratory tests to a schedule. This is done to detect possible pollutions Waste water (§ 47) 0.139 0.061 0.3 that show if the measured values are below the licensed of the environment due to radioactive substances during Direct radiation 0.61) 0.6 2) (§ 46) discharge values, the water is discharged into the river emplacement operations and afterwards. The results Total from 0.79 0.69 1 Aue via a pipeline. If the laboratory control measure- of this environmental monitoring are published. The discharge and direct ment shows that the licensed discharge levels have been opeator’s measuring programme is monitored by mea- radiation (§ 46) exceeded, the waste water is disposed of externally or surements carried out and supplemented by an indepen-

1) For exposure to radiation through direct radiation, the value for adults is also used for infants. solidified for disposal in the Konrad repository. dent measuring institution. 2) The threshold of 1 millisievert per year applies for direct radiation, less the exposure from discharge.

Comparison of calculated maximum exposure to radiation through direct Apart from the waste water, for example, also the What impact Konrad has on local produce and animal radiation and the discharge of radioactive material in exhaust air and exhaust air from the shaft or plants growing in the vici- products. waste water from the Konrad repository, with the threshold values contained in the Radiation Protection Ordinance. The effective dose is nity of the Konrad repository are controlled. The table on Model calculations prove that the consumption of local shown for the most exposed person (infant) and adults. page 33 shows what the monitoring programme provides produce and animal products of the region around the

32 Konrad repository will not constitute a risk to the popu- How radiation intensity is monitored. lation. The limit values set out in the Radiation Protection Transparency in terms of radiation exposure is provided Konrad terms Ordinance are safely complied with. In this case, too, the by the national Measuring and Information System for calculation of the potential radiation exposure is based the Monitoring of Environmental Radioactivity (IMIS) on the most unfavourable assumption, i.e. all food consu- which quickly detects the radioactive contamination med by a human being and the drinking water originate of the environment in case of an accident and which from the immediate vicinity of the facility. can assess the radiation exposure to be expected. An

Radiation Protection Ordinance (excerpt): § 46 Limiting radiation exposure to the population (1) For individual members of the public, the limit for the effective dose Planned monitoring programme for normal operation for radiation exposure during activities defined under § 2 para. 1 is 1 mSv per calendar year. Subject Monitored area Type of measurement Measuring points for Type and frequency of of environment taking samples sampling and measurement (2) Notwithstanding § 1, the limit for the organ dose for an eye lens is 1. Air 15 mSv per calendar year and the limit for the organ dose for the skin is 50 mSv per calendar year. 1.1 Air/ gamma dose rate 18 solid state dosimeters Half-yearly evaluation gamma dose rate at the plant fence (3) With respect to plants and facilities, the limit off premises for the

1.3 Air/aerosols a) Gamma spectrometry In the area of the most Cont. sampling over effective dose, as defined under paragraph 1 applies to the sum total of b) Total alpha activity unfavourable place of impact 14 days, Quarterly radiation exposure from direct radiation and radiation exposure due to in terms of inhalation evaluation discharges. The maximum lengths of stay in areas subject to radiation exposure due to direct radiation depend on the spatial circumstances 3. Soil/soil surface Gamma spectrometry In the area of the most Two samples per year each prevailing at the plant or facility or on the site; continuous stay is to be unfavourable place of impact assumed possible if no substantiated details on the length of the stay in terms of ingestion and are provided. a reference point

4. Plants/vegetation Gamma spectrometry In the area of the most Two samples per year each Emission: Discharge. unfavourable place of impact in terms of ingestion and Immission: Input of radioactive substances into the environment. a reference point

5. Surface water Ingestion: oral take-up.

Surface water a) Tritium activity Above and underneath Quarterly composite Radiation exposure: Effect of ionising radiation on the human body. concentration the discharge point in samples Whole-body exposure is the effect of ionising radiation on the whole b) Gamma spectrometry the receiving water human body. Partial-body exposure is the effect of ionising radiation on c) Alpha nuclide specific a single body parts or organs. External radiation exposure is the expo- measurement sure to radiation sources outside the body, internal radiation exposure is d) Sr 90 the exposure to radiation sources inside the body.

safety 33 important measuring installation operated by the Federal Office for Radiation Protection is the measuring network for the determination of external radiation exposure (dose rate – the external radiation human beings are exposed to depending on time and place). This network currently consists of around 1,800 stationary measuring points – dose rate probes – that have been distributed all over Germany.

In routine operation, the devices record the natural radi- ation exposure man is exposed to depending on place and time. It is composed of the radioactive substances occurring in the soil and of radiation originating in space. However, special importance is attributed to the network in terms of emergency precaution. If a radioactivity threshold value has been exceeded the system auto- matically triggers an alarm. If the increase is due to an accident, the probes can be read in 10-minute-intervals. This enables taking specific measures to protect the population, as the development and distribution of the radioactive cloud can be tracked accurately.

The Federal Office for Radiation Protection has already now set up measuring probes on the facility premises for test purposes. The currently gained values are to be taken as a basis for comparisons later on. Two additional probes will be set up at Konrad 2 later on.

All values are published on the Konrad website and in INFO KONRAD.

What about the long-term safety of the repository. To furnish the proof of long-term safety the long-term The distribution of ground radiance in Germany. development of the Konrad repository was prognosti-

34 cated with the help of geo-scientific methods. In model The concentrations of other non-radioactive pollutants calculations the dispersion of radionuclides from the were estimated following the boundary conditions and repository up into the groundwater near the surface was requirements of the radiological long-term safety assess- examined. It must be made sure that it will be possible ment. No disadvantageous changes to the groundwater at no time that radionuclides get into the groundwater in due to these pollutants need to be feared. Should they concentrations posing a risk to man and environment. It ever get into the groundwater the concentrations of was e.g. determined what maximum effects would have these substances will fall below the strict limits of the to be expected should the groundwater be used in agri- drinking water ordinance and other provisions and direc- culture or as drinking water. The boundary conditions tives according to water law. and input parameters of the model calculations were basically selected in such a way that they always cover Altogether, the possible impact on the near-surface the most unfavourable case, such as a relatively quick groundwater through the release of radionuclides and dispersion of radionuclides, and lead to results overrating other pollutants from the repository is so low that no the effects on man and environment. adverse effects to man and environment need to be feared. Parallel to this radiological long-term safety assessment it was examined whether non-radioactive pollutants con- tained in the waste such as lead or cadmium can lead to a damaging pollution of the groundwater or other adverse changes to its characteristics.

The model calculations show that radionuclides can get into the groundwater near the surface after 300,000 years at the earliest; that would be at first radionuclides such as iodine-129 which are hardly retained from the Earth’s crust. The transport of long-lived radionuclides with a higher retention level in the geosphere takes a lot longer. For example, the model calculations show for radium-226 that relevant concentrations would only have to be expected after several million years. That means: Further information is available on the During a period of between 300,000 and 360,000 years Internet at www.endlager-konrad.de. The employees in our information office, after the Konrad repository has been sealed, an infant InfoKonrad, will also be pleased to could only be exposed to maximum 0.26 millisievert per provide you with further assistance. year and an adult to maximum 0.06 millisievert per year.

safety 35 9. Legal and social requirements: Why Konrad is a complex challenge.

36 How the public took part in the plan-approval A site’s safety and suitability for the construction of a procedure. repository needs to be demonstrated in a nuclear plan- Konrad is the first repository in Germany that has been approval procedure on the basis of comprehensive proofs licensed according to nuclear law. A twenty-year-lasting including site-specific safety assessments. The Federal plan-approval procedure with participation of the public Office for Radiation Protection’s approach was confirmed was carried out. In the course of this procedure the key by the licensing authority, the Lower Saxon Environment documents were laid open to public inspection by the Ministry in Hanover and fully confirmed by the Lower Federal Office for Radiation Protection and were object Saxon Higher Administrative Court in Lüneburg, which of a controversial debate. Citizens had the option to view rejected all claims. The complaints against the non- the plan documents and to formulate their objections. admission of the revisions were rejected by the Federal More than 290,000 objectors, citizens, the local aut- Administrative Court on 26 March 2007. horities of Salzgitter, Braunschweig and Wolfenbüttel, and the environmental associations Greenpeace, BUND What the Konrad repository will cost. (Friends of the Earth Germany), AG Schacht Konrad, and By the end of 2007, the costs for the exploration and The public hearing in 1992 lasted 75 days. other citizens’ initiatives raised their protest prior to the planning works of the repository amounted to 945 mil- public hearing. lion euros. After the Federal Administrative Court had also judicially approved the Konrad licence in 2007, the The public hearing lasted 75 days and took place bet- conversion of the mine to a repository could start. Since The expenditures for the competent federal authorities ween September 1992 and March 1993 in Salzgitter- then the Federal Office for Radiation Protection (BfS) and other contractors amount to approximately 76 Lebenstedt under the leadership of the Lower Saxon has been working on the available planning and licen- million euros for this period. Approximately 51 percent Environment Ministry. On this basis the Environment sing documents large parts of which originate from the of the construction works planned altogether has been Ministry made a decision about the application for appro- 1980ies and are based on unrealistic assessments of the implemented so far, so that additional increases in costs val of the plan and granted the licence for the Konrad time and effort for planning, modification and licensing. are to be expected. repository in 2002. Some objectors filed a court action Until 2007 it had been the federal governments’ policy against the decision. guideline not to work on the planning documents for Which question additionally concerns local residents. the Konrad repository while they were being examined Again and again concerned local citizens pose the follow- What legal steps the Konrad project had to go through. by the licensing authority and during the court procee- ing question: In case it will be retrieved, will the entire The legal claims against the plan-approval decision dings, i.e. it was not possible to up-date them to the waste from the Asse mine be stored in Konrad? (licence) were decided by the Lüneburg Higher Admini- state of the art of science and technology. Meanwhile strative Court until 8 March 2008. the operating company DBE has carried out a continu- Should it be possible to recover the waste from the Asse ously up-dated project cost accounting under current mine – a question that can only be answered after the boundary conditions. Accordingly, the costs for the trial phase (fact finding) has concluded – the waste needs construction of the Konrad repository from 2007 until to be newly packed i.e. conditioned to begin with, then it Left photo: German Bundestag. completion amount to approximately 1.6 billion euros. needs to be stored in an interim storage facility until a

legal and social requirements 37 repository will be available. There are two good reasons be determined later on. Thus only a licensing procedure against direct disposal of the Asse waste in Konrad: at the NMU would probably enable storage in the Konrad repository. Firstly, the plan-approval decision for Konrad provides for an emplacement volume of maximum 303,000 cubic What resistance there is in the region. metres of low-level and intermediate-level radioactive The protests against the future Konrad repository have waste. The waste volume prognosticated until 2050 not stopped, not even after the licence had been granted amounts to approximately 290,000 cubic metres. The in 2002. Not only do organised groups offer resistance total volume of the Asse waste, however, would amount – such as the AG Schacht Konrad – and express their to approximately 100,000 cubic metres. This would concerns but also local residents take part in actions Pupils pay a visit to the information centre INFO KONRAD. exceed the capacity Konrad is licensed for. Secondly, the against the repository. For example, in February 2009 waste from Asse does not comply with the Konrad waste approximately 15,000 people formed a 56-km-long chain acceptance requirements. In addition to the plan-appro- of light reaching from Brunswick over the Asse mine for Radiation Protection presents the Konrad repository val decision the permit according to water law for the up to the Konrad mine in Salzgitter-Bleckenstedt. With on 250 square metres of exhibition space. Apart from a disposal of radioactive waste in the Konrad repository their motto “light into the dark” they demonstrated their model of the future mine area, presentation charts and needs to be observed. In this permit it is laid down how being opposed to the repository projects. The citizens a cinema, modern touchscreens animate visitors to look many of the altogether 94 substances significant to the are concerned about the future, about future generations into the subject of Konrad. groundwater may be contained in the waste packages. It and the possible radiation exposure that could emanate is quite unlikely that the waste stored in the Asse mine from the repository. Information on the repository is not only availa- will fulfil these requirements and that the ingredients can ble in INFO KONRAD. Interested persons can also How the public is informed about Konrad. reach the INFO KONRAD team via e-mail and phone The Federal Office for Radiation Protection takes the citi- *49 (0) 5341 8673099. Additionally, the Konrad web- zens’ fears and concerns seriously and addresses these site www.endlager-konrad.de provides comprehensive concerns. In order to make sure that the topic of Konrad information about the history, conditioning of the waste, continues to be treated with a high level of transparency, geology and the planned transports. The website also the Federal Office for Radiation Protection takes several provides interactive highlights and animations. Further- measures to inform the population about all projects and more, there is a mobile information centre which provi- running works around the Konrad repository. des information in situ, e.g. in schools.

In the information centre INFO KONRAD in Salzgitter- What controls the Federal Office for Radiation Protec- Lebenstedt, Chemnitzer Straße 27, the Federal Office tion is subject to. Different institutions are competent for the safety of the Konrad mine and for compliance with and implementation Signs of resistance in the region around Konrad. of all provisions contained in the plan-approval decision.

38 The Federal Ministry for the Environment, Nature Con- servation and Nuclear Safety has the technical and legal supervision over the Federal Office for Radiation Protec- tion. The Lower Saxony Environment Ministry must give its consent to the Federal Office for Radiation Protection for all significant changes of the licensed plan.

Minor changes to the plan-approval decision are controlled by the BfS Repository Surveillance – Nuclear Supervision of the Federal Office for Radiation Protection – which is a self-contained organisational unit examining all techni- cal and legal issues with respect to the construction and operation of the Konrad repository. This is also supervised by the federal ministry. Through this regulation it is made sure that the federation and the federal state cope with their responsibility for the safe operation and decommis- sioning of the Konrad repository.

As a form of protest, 15,000 people took part in the chain of light.

legal and social requirements 39 10. Space for your notes.

40 41 einf¸hnorutnesg 41 11. Dialogue with Konrad.

42 Title/First name/Last name* POSTAGE PAID

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With organic ink on unbleached, 100% recyclable paper Daytime telephone no. Publisher: Information Point of the Federal Bundesamt für Strahlenschutz Pictures sourced from: E-mail address Office for Radiation Protection Postfach 100149 Federal Office for Radiation Protection, BAM, DBE, EWN, 38201 Salzgitter, Germany INFOKonrad GNS, Marc Steinmetz (Seiten 10, 13, 18, 26, 28), FZK Date of birth Phone +49 (0) 30 183 33-0 Chemnitzer Strasse 27 Fax +49 (0) 30 183 33-1885 Picture left: The Federal Office for Radiation Protection information Updated: Profession [email protected] · www.bfs.de centre for the future Konrad repository. March 2011 38226 Salzgitter *Required details Germany

02 kontakt Tell us what you think.

Our aim is to create transparency and being more available to citizens. Enter into dialogue with us – we are looking forward to it.

How satisfied are you in general with the transparency of Konrad and our availability to citizens? Creating confidence through safety. Very satisfied Satisfied Not satisfied Reason:

How do you like this information brochure? Creating confidence through safety. I like it a lot I like it Don’t like it Reason:

How satisfied are you with the Konrad communication in the Federal Office for Radiation Protection’s information centre INFO KONRAD (exhibition, touchscreens, film, shaft model, personal talk)? Very satisfied Satisfied Not satisfied No experiences yet Reason: Konrad repository.

Place for further questions and suggestions:

Answers to the most frequently asked questions. " Challenge us – or ask for more material.

We would like to answer all your questions about the Konrad topic. Enter into dialogue with us – we are looking forward to it.

I would like to make an appointment for a personal talk. Please call me about this issue.

Yes, I would like to go more in depth. Please call me to arrange an appointment with me for visiting the InfoKonrad Konrad mine. Chemnitzer Strasse 27 38226 Salzgitter, Germany I am interested in topics other than Konrad the Federal Office for Radiation Protection deals with. Phone +49 (0)5341 867 3099 Fax +49 (0) 3018 333 1285 I am planning a mobile exhibition on the topic in a public institution. [email protected] Please call me about this issue. www.endlager-konrad.de

43

Konrad repository. Science creates trust. Publisher: Bundesamt für Strahlenschutz Postfach 100149 38201 Salzgitter, Germany Phone +49 (0) 30 183 33-0 Fax +49 (0) 30 183 33-1885 [email protected] · www.bfs.de

02 Contents

Preface 04 1. General Ionising radiation: radioactivity and types of radiation. 06 2. Introduction Konrad: thoroughly examined from top to bottom. 10 3. Chronicle History of the approval procedure: a review. 14 4. Surface installations The mines: facts, figures, data. 17 5. Geology Konrad: the discovery. 18 6. Mine Underground: from ore mine to repository . 22 7. Planned repository mine Field 5: the prerequisites. 26 8. Hydrogeology Water: the repository keeps (water) tight. 27 9. Rock mechanics and seismology The future: predictably safe. 30 10. Long-term geological prognosis Calculations: the prospects are good. 31 11. Radioactive waste Distinguishing feature: heat generation. 35 12. Repository conditions Waste: requirements and implementation. 38 13. Waste receptacles Packaging: types and requirements. 42 14. Product control Monitoring: an on-going process. 44 15. Storage The process: delivery and storage. 46 16. Safety analyses Operation: responsibility towards people and the environment. 50 17. Interview “The public has no reason for concern.” 56 Appendix Mining Technology 60 Glossary A – Z guide to Konrad 62 Contact and Publication Details 71

Contents 03 Preface

In accordance with try either. As a result of the “Agreement between the 2007. On that day, the Federal Administrative Court in the Atomic Energy Federal Government and the Utility Companies” of 2001, Leipzig rejected applications against the Konrad repo- Act, the last nuclear and with the legal safeguard provided by the amendment sitory in the final instance. The extensive authorisation power station will be to the Atomic Energy Act of April 2002, the quantitative procedure, coupled with the decisions, confirms Konrad’s switched off in Ger- problem of radioactive waste is limited. Since 2002, suitability as a repository for low and intermediate level many in 2021. This Germany has had a repository which is authorised, in radioactive waste. will end the use of accordance with the Atomic Energy Act, for radioactive Large sections of the population are sceptical about the nuclear energy in waste with negligible heat generation: the Konrad reposi- Konrad repository, fearing negative consequences. The Germany. Its legacy, tory, a former iron ore mine in Salzgitter. Federal Office for Radiation Protection takes these fears however, will continue In order to ensure that commercial interests, such as cost seriously, in particular with regard to waste that has to to occupy people for reduction and profit maximisation, do not play any kind be stored for a long time. a long time to come. of role, the disposal of radioactive waste in Germany is This is particularly state business; the prime issue being safety. The task of Transparency and the willingness to communicate true for the disposal Wolfram König, President of The Federal constructing and operating repositories for radioactive The Federal Office for Radiation Protection will continue of radioactive waste. Office for Radiation Protection waste falls to the Federal Office for Radiation Protection. to take all issues related to safety seriously and to moni- Even before the final This authority has a proven record of demonstrating its tor all future situations. It is open to suggestions and nuclear power phase-out, Germany needs a repository for commitment to taking the responsibility seriously. This ideas. Only through transparency and the willingness to low and intermediate level radioactive waste, which acc- can be seen, for example, in the ways it dealt with the communicate will we succeed in generating trust. rues particularly when nuclear power stations are shut legacy of the former repository in Morsleben on the one down. Today, there are already more than 88,000 cubic The Konrad repository is different from all previous pro- hand, as well as the interim storage facilities authorised metres of radioactive waste with negligible heat gene- jects for repositories in Germany. It is the first repository by the Federal Office for Radiation Protection on the ration in interim storage facilities and state collecting to be authorised under the Atomic Energy Act. Morsleben other. depots. Federal German waste disposal policy is based was constructed in an undemocratic country without the on the principle that disposal is a domestic issue, mea- The Konrad repository was authorised in 2002 by Lower general public being consulted; the Asse mine was also ning that radioactive waste from German reactors may Saxony’s Environment Ministry following a plan approval equipped as a research mine without the general public not be exported to other countries. By the same token, procedure extending over 20 years. The German Supreme being consulted and was operated according to mining radioactive waste may not be imported into the coun- Court confirmed the licence for Konrad on March 26, and radiation protection laws.

04 A further important difference between the Morsleben technical terms have been summarised in a glossary at and Asse facilities and the Konrad repository are the geo- the back of this brochure. logical conditions. Konrad had originally been operated This brochure is suitable for all those who wish to find as an iron ore mine, but only for a short time. It does not out in more detail all there is to know about the Konrad therefore show the same signs of high frequency usage repository. Questions can also be put directly to the as, for example, the old salt mines at Morsleben and staff at the Federal Office for Radiation Protection (BfS) Asse, which were used to dispose of radioactive waste. at Info Konrad Chemnitzer Straße 27 in Salzgitter- Not only that, but storage in the Konrad repository will Lebenstedt; telephone +49 (0) 5341 8673099 and to not be in cavities excavated in earlier times, all disposal [email protected] by email. galleries will be newly excavated. The ore deposits them- selves are found at a depth of 800 to 1,300 metres under the Earth’s surface and are unusually dry. A 400-metre thick clay-bearing barrier seals the mine both against groundwater and the branch canal crossing Salzgitter that is situated above it.

Wolfram König Mistakes made in the past must not be repeated. We owe President of the Federal Office for Radiation Protection it to coming generations to safely shield all radioactive legacies from the biosphere.

This brochure aims to provide open communication and transparency on the subject of the Konrad repository. Not only does it provide the reader with comprehensive information at the scientific level, it also contains a large number of descriptive diagrams and images. The origin of radioactive waste, the planned storage procedures and the geological and hydrological conditions in the Kon- rad repository are all described here in detail. The key

pr ace 05ef 1. General Ionising radiation: radioactivity and types of radiation.

The process of radioactive decay is one in which a less outside the body. Alpha particles can only penetrate the ding on their intensity. If they are incorporated, typical stable atomic nucleus achieves a more stable state. surface of the skin to a depth of a few micrometres (1 beta emitters such as strontium-90 or iodine-129 are This so-called nuclear transformation process cannot be micrometre = 1/1,000 millimetre) where it does not cause deposited primarily in certain organs of the body (stron- influenced from outside, but occurs spontaneously. The any damage. In the event of incorporation, however, the tium-90 in bones, iodine-129 in the thyroid gland) where radiation (alpha, beta, gamma and neutron radiation) dangerous potential of alpha radiation is considerably they cause high local radiation exposure. generated during the nuclear transformation has the pro- higher. Severe damage can be caused to the mucous perty of ionising matter. Although the term ‘radioactive membrane, which does not have a protective layer of Gamma radiation radiation’ is widely used, the correct expression is ‘ioni- skin. Gamma radiation is electromagnetic radiation. It is of sing radiation’. The following types of ionising radiation the same physical nature as light, but possesses con- can occur during nuclear decay: Beta radiation siderably higher energy content and can pass through Beta radiation is particle radiation in the form of matter at high speed. Due to this property, it makes little Alpha radiation electrons (beta particles). In air, the ability of beta parti- difference whether the source of radiation is inside or Alpha radiation is particle radiation in the form of nuclei cles to diffuse is between a few centimetres to metres; in outside the body. In order to avoid radiation damage by of the helium element (alpha particle). In air, alpha emit- soft tissue or synthetic material it is a few millimetres to gamma emitters, the source requires a highly effective ters have a short range of only a few centimetres and are centimetres. Beta emitters enter deeper into the layers shield, for example lead, steel or concrete. With the therefore more or less harmless as long as they remain of the skin and can therefore cause severe burns depen- exception of their mode of production, gamma radiation is comparable to x-radiation.

Helium atom Electron Photon

Proton

The different types of ionising radiation differ in their range: Neutron Alpha, beta and gamma radiation (from left to right).

06 Neutron radiation Neutrons are electrically neutral elementary particles. They are particularly released during nuclear fission, a special form of nuclear transformation. Nuclear fission is only characteristic for heavy atomic nuclei, such as uranium, and occurs in nuclear reactors among other places. Matter that is exposed to neutron radiation can become radioactive. It is not possible to shield neutrons using materials with a high atomic number (for example lead). Fast neutrons have to be decelerated (moderated) before being captured with the aid of neutron absorbers (for example boron or cadmium).

Radiation exposure and dose When ionising radiation comes into contact with the human body, radiation exposure occurs. This means that radiating particles enter into an interaction with body tis- sue and are absorbed in differing amounts. The ‘amount’ of radiation absorbed by the body is given in units of radi- ation dose. The unit for the absorbed radiation dose is the gray (Gy). One gray is equivalent to one joule per kilo- gramme (1 Gy = 1 J/kg). However, the biological effects of the different types of radiation on body tissue differ in their intensity. This means that the biological effect of radiation on the human body cannot be adequately described simply by giving the units of energy dose.

Photo right: Radioactivity is invisible, but ever-present.

GENERAL 07 Type of radiation Weighting factor X-radiation and gamma radiation 1 Beta radiation 1 Neutrons, dep. on energy 5 … 20 Alpha radiation 20

Radiation weighting factors given by the International Commission on Radiological Protection (ICRP).

Radiation weighting factor For this reason, the energy dose is multiplied with the aid of so-called radiation weighting factors which take the biological differences of the radiation effect into account. The units of measurement for these weighting factors for different types of radiation are chosen so that they represent the measure of their biological effects in low Photo above: The activity of radioactive substances in exhaust air and wastewater is monitored during operations at the Konrad repository. They may not exceed 0.19 mSv p. a. doses (see above table). The weighting factor for radia- tion with low ionisation density in tissues, such as gamma naturally occurring radiation. It is now known that ionis- It therefore follows that each radiation exposure repre- and beta radiation, is given as 1. Allowance is made for ing radiation, regardless of whether it comes from a natu- sents a risk of disease. The limiting values contained the more intense biological effect of radiation with high ral source or an artificial one, can have harmful effects. in the Radiation Protection Ordinance must therefore ionisation density – such as alpha and neutron radiation guarantee that the risk for the population is maintained A differentiation is made between the somatic effect, – by assigning a higher value to the weighting factor. at a low level. Dose limiting values are often erroneously which occurs directly in the exposed organism, and For assessing biological effectiveness, the radiation- regarded as being the dividing line between ‘dangerous’ the hereditary effect, which may well only occur in weighting factors of the ICRP have been adopted by descendants of the exposed person. A further differenti- and ‘harmless’ radiation exposure. Continuing violation the Federal Republic of Germany and are given in the ation is made between the deterministic and the stocha- of the limiting values would mean that radiation expo- Radiation Protection Ordinance. stic effects of radiation. Whereas the degree of determi- sure for the individual is equivalent to a radiological risk, Once the biological effectiveness of radiation has been nistic radiation damage depends on the size of the dose, which has been rated unacceptable by the legislator. taken into account, the dose is then referred to as the in the case of the stochastic effect, only the probability dose equivalent. It is calculated by multiplying the energy of damage occurring depends on the size of the dose. Minimisation directive from the Radiation Protection dose (in gray) by the radiation weighting factor. The unit Ordinance The minimisation directive from the Radiation Protection used for the dose equivalent is the Sievert (Sv). Dosage and risk All theories of radiation protection are based on the Ordinance is based on the assumption of a linear dose- Effects of ionising radiation on people assumption that a zero-threshold value below which there response relationship that extends to values below those All life has developed under the influence of sources of is no risk of radiation-induced disease does not exist. of the limiting values. This binds the operator of an instal-

08 Technologically enhanced radiation (total approx. 2 mSv/p.a.)

Medicine 1.9 mSv/p.a.

Nuclear reactors < 0.01 mSv/p.a.

Fallout from nuclear bomb < 0.01 mSv/p.a.

Chernobyl < 0.015 mSv/p.a.

Research, technology, household < 0.01 mSv/p.a.

Exposure to natural radiation Technologically enhanced radiation Limiting values for Konrad (also technologically enhanced; total approx. 2.1 mSv/p.a.) (total approx. 2 mSv/p.a.) The limiting value for radiation exposure for an individual

Inhalation of radon person as a result of operations at the Konrad reposi- and radon decay tory has been set by the Radiation Protection Ordinance products Medicine 1.1 mSv/p.a. 1.9 mSv/p.a. at 1 millisievert per annum and applies to radioactive discharge and direct radiation. Conservative estimates Direct cosmic Nuclear show that the maximum level of radiation exposure from radiation reactors 0.3 mSv/p.a. < 0.01 mSv/p.a. the discharge of radioactive substances in exhaust air and wastewater while the Konrad repository is running Fallout from nuclear bomb cannot exceed 0.19 mSv p.a. With the level of potential < 0.01 mSv/p.a. exposure to direct radiation being less than 0.6 mSv Direct terrestrial p.a. at the fence of the installation, the total amount of radiation Chernobyl 0.4 mSv/p.a. < 0.015 mSv/p.a. potential radiation exposure at this worst possible loca- tion would be below 0.8 mSv p.a. All of these values are Research, Food technology, calculated ‘maxima’; the values during actual operations 0.3 mSv/p.a. household < 0.01 mSv/p.a. will be lower.

Average annual effective dosage from ionising radiation, averaged for the population of the Federal Republic of Germany.

lation to keeping all radiation exposure or contamination Radioactive exposure of the population in Germany Exposure to natural radiation Type of examination Effective dose average annual affecting people and the environment values – including E(alsoveryone technologically is subject enhanced; to a certain total degree approx. of 2.1 radioactive mSv/p.a.) per application exposure per (mSv/p.a.) inhabitant (mSv/p.a.) those below the limiting values – as low as possible. It exposure from both natural and technologically enhan- Inhalation of radon Dental x-ray < 0,01 < 0,5 also binds the operator to giving due consideration to ced sources. The annual amount of individualand radon radiation decay Chest (thorax) 0,02–0,05 0,5–1,8 products x-ray all individual circumstances and state-of-the-art science exposure can vary enormously. In Germany,1.1 mSv/p.a. the average Bilateral mammography 0,2–0,6 0,2 level of natural radiation exposure is approximately 2.1 and technology. at two levels (organ dose 4 – 12) mSv per annum and depends on the individual’sDirect cosmic place Only by linking limiting values and optimisation measures of residence and daily habits. The level radiation of technologi- Computer tomography 10 1–2 0.3 mSv/p.a. Abdominal area is it possible to ensure that appropriate radiation pro- cally enhanced radiation exposure in Germany is around tection is provided and that the risk of disease for the 2 mSv per annum and is caused primarily by medical Comparison of different levels of radiation exposure during medical workforce and the population as a whole can be viewed applications in general, and x-ray diagnostic equipment examinations, average values for effective dose for standard patients as being low. with 70 +/- kilograms bodyweight. in particular. Direct terrestrial The organ dose to the thorax during a mammography is 4 to 12 mSv. radiation 0.4 mSv/p.a. This is equivalent to an effective dose of between 0.2 and 0.6 mSv.

Food 0.3 mSv/p.a. GENERAL 09 2. Introduction Konrad: thoroughly examined from top to bottom.

Mining has a long tradition in the area around Salzgit- tres wide, but at no point does it make contact with the Key 0 5 10 km Vorhop ter. The first settlements, in what is now the town of surface. It has been explored to a depth of between 800 ELM Salt pillow

LEHRE WESENDORF Salzgitter, were founded because of natural salt springs, and 1,300 metres. Salt structure N Wesendorf VORHOP SCHNEFLINGEN which had been known for as long as two thousand years. Iron ore region The deep location of the ore, which was deposited around (based on H. Kolbe) Settlement was facilitated by the fertility of the soil, Upper Jurassic 150 million years ago in the Upper Jurassic (Malm), also Aller abundant spring water, salt and all other essential mate- Flowing waters, canal explains why it was not discovered until oil drillings Motorway

rials such as the highly sought-after ironstone. WEYHAUSEN were carried out in the 1930s. Actual exploration of the GIFHORN Meinersen Aller The iron ore deposits had been the basis of industriali­ southern section of the deposit, where the Konrad mine Gifhorn Leiferde Calberlah sation in the Salzgitter area since the 19th century. They is located, was carried out in the 1950s and 60s. Oker Wolfsburg were found in exploitable form in three surface areas Rolfsbüttel BERKHÖPEN

EMMEN and originated from the Early and Late Cretaceous peri- A 2 The foundation Midland Canal HEILIGENDORF

ods. Ore output first began in 1867, in the “Finkelkuhle” In December 1954, two companies, Salzgitter-Erzberg- Meerdorf ROLFSBÜTTEL SZ-Peine Lehre mine not far from Salzgitter-Ringelheim. The last mine in bau AG and Ilseder H¸tte AG, founded the Konrad mining Peine A 2 DORM

WENDEBURG the region to be operated was the Haverlahwiese mine, LEHRE company. Two years later, on July 5, 1956, Salzgitter- Salzgitter canal branch IH-Emilie A 39

where ore deposits had been known to exist since 1837, Erzbergbau AG announced that it would commence A 391 Braunschweig GR. ILSEDE Oberg and which was closed down in 1982. Here, too, ore was mining for iron ore, the deposit reserves of which were SALZDAHLUM Upper Cretaceous Groß Gleidingen

MÖLME VECHELDE ELM Mölme Lengede KL. first mined from the open pit. Adits followed in 1845. estimated at 1.4 billion tonnes of oolitic iron ore with an A 39 IH-Lengede SCHÖPPEN- STEDT IH-Barbecke Broistedt estimated iron content of between 27 and 33 percent. By SZ-Thiede SZ-Konrad BROISTEDT Wolfenbüttel SZ-Hallendorf the time production was closed down in 1976, however, SZ-Lebenstedt THIEDE Location and depth SZ-Watenstedt ASSE

The Konrad mine is the youngest of the former iron ore only 6.7 million tonnes of ore had been mined. HOHENASSEL

SALZGITTER SZ-Haverlahwiese mines in the Salzgitter area and differs considerably Innerste SZ-Hannoversche Treue FLACH- WERLA- Konrad Shaft 1/2 from those at the other locations. The extensive iron STÖCKHEIM BURGDORF SZ-Ohlendorf SZ-Finkenkuhle Former iron ore mine ore deposit is part of a system of rim synclines, the ore- Lower Cretaceous

SZ-Georg carrying area of which extends over 60 kilometres from B-Ida A 7 A 395 B Barbara Salzgitter-Hallendorf across to the Vorhop area north of B-Fortuna IH-Georg-Friedrich IH Ilseder Hütte B-Morgenstern SZ Salzgitter Gifhorn. The iron ore body is between 8 and 15 kilome- Iron ore deposits in the Salzgitter area as far as Gifhorn.

10 Qualification as a repository The Konrad mine is exceptionally dry for an iron ore mine. In storing toxic waste in the deeper geological under- ground, the decisive medium for a possible return of the contaminants to the biosphere is water. Preliminary investigations carried out in 1975 at the suggestion of the works council of that time showed that, in principle, the mine could be a possible repository for radioactive waste.

In addition to the deep location of the iron ore bed, a primary feature is the good sealing protection against groundwater afforded by the overlying strata, which is chiefly composed of surface-close mudstone and marlstones.

Investigations and analyses In the period between 1976 and 1982, the Gesellschaft f¸r Strahlen- und Umweltforschung (today known as the Helmholtz Zentrum M¸nchen – Deutsches Forschungs- zentrum f¸r Gesundheit und Umwelt GmbH) carried out a study on behalf of the Ministry for Research and Techno- logy (now the Ministry for Education and Research) which focused on the geological and mining-related conditions in the Konrad iron ore mine with regard to its potential as a repository for radioactive waste. Following the posi- Photo above: One of the underground galleries in the future Konrad tive conclusion of the study, the Physikalisch-Technische repository. Bundesanstalt, (the predecessor of the Federal Office for Radiation Protection) filed an application on August based solely on samples taken from drillings and from on the basis of the ‘Safety Criteria for the Disposal of 31, 1982 for a plan approval procedure to be initiated. mine openings. In order to attain safety certification and Radioactive Waste in a Mine’, which had been passed in However, the submitted documents – the ’plan’ – were complete the plan, a site investigation programme was 1983 by the German Ministry for the Interior. incomplete at the time since the suitability studies were therefore launched simultaneously. This was conducted

INTRODUCTION 11 Photo above: Researchers inspect the Konrad mine.

Researchers focused particularly on Depth drilling close to Shaft 2 provided information on Findings of the study the barrier properties of the overlying strata and possible The up to 400 metre-thick mud and marlstone layers of the formation of the mineral deposits and the rock aquiferous strata over- and underlying the ore deposits. the Lower Cretaceous, which form the most important strata above and beneath them; Down to its total depth of 1,001.75 metres, the drilling geological barrier to the envisaged repository, demons- the broad geological formations; specified as ‘Konrad 101’ provided a geological profile all trated only minimum permeability. There is also only a very small degree of permeability in the chalk and the hydrogeological conditions in the overlying the way through the overlying strata to that of the over- strata, in the ore deposits and in the underlying lying ore deposit. marlstone layers of the coral oolite, including in the iron oolite. Only in the deepest part of the coral oolite were strata; The profile is shown in the presentation on the right. two joints with high degrees of permeability found. By the hydrochemical state of the aquifer from As the drillings were completely cored and measured way of conducting an in-depth examination of and cha- quaternary, chalk and Jurassic and the hydrological using borehole probes, a great deal of valuable informa- racterising the thickness of the strata and the tectonics conditions; tion was gained on the stratigraphic sequence in the area in the area of the Konrad mine and its surroundings, of the Konrad mine. Since the hydraulic properties of the the properties of the geological formations in the scientists carried out seismic reflection tests, which function of diffusion barriers for radio-nuclides rock in the over- and underlying strata of the envisaged resulted in approximately 80 kilometres of seismic pro- disposal horizon could now also be explored, a review of (permeability, sorption behaviour); files. This is an immense improvement on the existing previous drilling profiles, in conjunction with exposures level of knowledge on the geological formations. Under- the state of the rock mechanics in the area of from the underground explorations, led to the develop- ground explorations have revealed that disposal cham- chambers, galleries and the entire mine; and ment of new ideas on the nature of the palaeogeographic bers with an overall volume of approximately 1.1 million the long-term seismic stability of the location. limits of the ore deposits. cubic metres are possible.

12 Depth Litholog. Lithologie in m Profile Quaternary Pleistocene Gravel and sand 560 Thieder silicified marl bank

Limestone and limestone marl “white Pläner” Hauterivian

clay and clay marl Upper Turonian green-grey layers, Tuff Upper Hauterivian 600 50 clay marl, green, grey clay and clay marl Lower Hauterivian Lime marl banks brown iron ore Turonian Limestone, clay marl Limestone and limestone marl “white Pläner” Kimmeridgian Lower Kimmeridgian

Upper Cretaceous Middle Turonian 650 100 Upper Coral Oolite Limestone, oolitic Begin of the red colouring, partly cloudy Clay marl regeneration layer Limestone marl Oxfordian

Red limestone with red-brown marl layers “rot Pläner” Malm Upper deposit Limonitic ore, limestone, (ore-rich carbonate) Middle Inter- Lower Turonian 700 Clay marl with ore, sand and coquina 150 Limestone Coral Oolite burden Lower deposit Brown iron oolite with sand and coquina Clay marl Ore-rich carbonate series with ferrous oolitic limestone, fine sand deposits Upper Cenomanian Limestone “impoverished rhoto. magense layer” Cenomanian Lower “Pancake mudstone”, clay marl, Brecciated limestone Middle Cenomanian Lime marl 750 Coral Oolite 200 approx. 220- Calcereous breccia series 230 m fresh- water Clay marl Upper Callovian Gryphea unit Lower Cenomanian salt- Athleta Zone water boun- Lime marl, clay marl and claystone dary Clay marl and claystone 250 alva Btoin Bajocian Bathonian Callovian 800 with silt and fine sand

Jurassic Coronata Zone Jason Zone Middle Callovian Carbonatic geodes

Strongly fractured area Cretaceous Clay and clay marl, silty 300 Upper Albian 850 Lower Callovian Claystone, clay marl Claystone, fine sand conductive Phosphorite concretions Dogger Upper Bathonian Mica, goedes Claystone, very fine sand conductive Cornbrash sandstone Limestone-sandstone, clayey deeper layers 350 900

Albian Lower Bathonian Clay marl Middle Albian silty, partly fine-sandy and glauconitic Upper Parkinsoni Zone Clay and clay marl, silty and fine sandy abundance of pyrite, mica Fine sandstone Lower Cretaceous Upper Bajocian Carbonatic and phosphoritic geodes 400 Clay and clay marl 950 silty and fine-sandy, glauconitic Claystone, silty, fine sandy, micaceous Lower Parkinsoni Zone abundance of pyrite Lower Albian Clay ironstone geodes

Garantiana Zone Claystone, silty Subturcatum Zone Condensation horizon Claystone 450 End depth 1.000 Middle Bajocian Hils Sandstone Fine sandstone, glauconitic Fine claystone Aptian Upper Aptian Glauconite, tuff Fine sandstone bank Tuff and conglomerate Upper Barremian Clay and clay marl

Barremian 500 Lime marl

Clay and clay marl, “Blätterton”, bituminous Middle Barrenian silty

Fine sand deposits Clay and clay marl, “Blätterton”, bituminous 550 Lower Barrenian Geological profile of the Konrad 101 depth drilling.

INTRODUCTION 13 3. Chronicle History of the approval procedure: a review.

1975: first preliminary investigations Environment. The ministry confirmed that the plan was investigations – which they outlined in a summary at the The first analyses with regard to the disposal of radioac- suitable for submission and prepared to make it public. end of 1990 – the state of Lower Saxony still saw the tive waste were carried out in the mid 1970s, at a time On May 16, 1989, however, the Minister-President of the need for improvements. when the Konrad iron ore mine was still operational. In time, Ernst Albrecht (CDU), halted the process. The state 1976, ore mining was stopped because it was running at government demanded that the following conditions be 1991: the plan approval procedure continues a loss; the investigations into the suitability of the mine fulfilled before the process could be continued: confir- On January 24, 1991, the state of Lower Saxony received as a repository continued. mation that the product control for reprocessing nuclear a federal directive to continue with the plan approval waste abroad conformed to the requirements of the plan procedure and to make the scheme public. 1982 the plan approval procedure begins approval procedure; assurance that only waste origina- The federal directive was published on May 8, 1991, and PTB, the German metrology institute that provides ting from the German fuel cycle would be disposed of; the application documents were made available for public scientific and natural services, requested in 1982 that and that there would be financial compensation for the examination over a two-month period. Around 290,000 a plan approval procedure be initiated. Following a pro- planned repositories in Gorleben and Konrad. objections were registered with the approving authority. gramme of extensive site investigations, the plan was pre- Following further re-examination of the plan, made neces- sented to over 70 authorities and environmental groups sary by an amendment to the Radiation Protection Act in 1992: the hearing for commentary; the need for amendments was esta-­ 1989, the hitherto final version was drawn up. In the fol- The hearing began on September 25, 1992 in Salzgitter- blished. lowing year, the Lower Saxony Ministry for the Environ- Lebenstedt and ended on March 6, 1993 following a total ment informed the Federal Office for Radiation Protection The Konrad project was accompanied by an intensive of 75 days of negotiations. public relations campaign that included opening an that the plan was suitable for submission and the public In October 1992, 4,000 people took part in a demonstra- ‘Information Centre for Nuclear Disposal’ in Salzgitter in participation process was initiated. That same year, the tion against using the Konrad mine as a radioactive waste May 1983. This was one of the biggest schemes prior to CDU lost power in the Lower Saxony election. The new repository. Wackersdorf. SPD-led government saw unresolved security issues at the Konrad site as well as the need for an environmental 1994: application for immediate enforcement 1989: submission of plan and amendment to the impact assessment under the terms of a law that had been In 1994, the Federal Office for Radiation Protection, Radiation Protection Act passed in 1990. Although the Federal Office for Radia- giving detailed justification, applied for immediate In the spring of 1989, the PTB submitted the plan to tion Protection held the opinion that the environmental enforcement of the plan approval resolution. In the same the then responsible Lower Saxony Ministry for the impact assessment had already been included in the

14 2000: “nuclear moratorium” In the 2000/2001 nuclear moratorium, it was agreed that the plan approval procedure would be completed in accordance with the legal stipulations, and the appli- cation for immediate enforcement withdrawn. Out of respect for the plaintiffs and the general public, it was agreed that no fait accompli would be presented prior to a legal investigation. The outcome of the court procee- dings was also to be awaited before further public funds were to be invested.

2002: the plan approval resolution is granted Following the withdrawal in 2000 of the application for immediate enforcement, the plan approval resolution was granted by Lower Saxony in June 2002.

2006/2007: the plan approval resolution is confirmed by the supreme courts Municipalities, counties, parishes and private individuals filed a total of eight lawsuits against the decision. The

Photo above: The 1992 hearing lasted 75 days. lawsuits were not directed against the Federal Office for Radiation Protection, but against the Lower Saxony year, the Federal Ministry for the Environment, Nature Office for Radiation Protection submitted final approval Ministry for the Environment and Climate Protection as Conservation and Nuclear Safety presented a draft plan documents in 1997. A year later, the Federal authority the approving authority. The parishes and counties later withdrew their lawsuits. approval resolution that had been compiled with the assi- issued a directive confirming justification for the plan. stance of Gesellschaft f¸r Anlagen- und Reaktorsicher- On March 8, 2006 the Administrative Appeals Tribunal heit (GRS). Lower Saxony rejected the use of the draft. 1998: the procedure grinds to a halt in Luneburg dismissed the lawsuits without allowing an By 1998, the approving authorities had prepared an appeal. 1995: the plan approval resolution begins to be almost complete plan approval resolution when the pro- However, a number of plaintiffs lodged a complaint with drafted cedure was stopped to allow the Federal Office for Radi- the Federal Administrative Court in Leipzig against this In 1985, the approving authority began drafting its own ation Protection to review the approval documents with decision. On March 26, 2007, the Federal Administrative plan approval resolution. With this in mind, the Federal regard to transport safety. Court dismissed the complaints lodged by the town of

CHRONICLE 15 Salzgitter, the municipalities of Lengede and Vechede, now final and enforceable. No further means of recourse 2008: the main operating plan is approved as well as by a farmer from Salzgitter against the rulings are possible. The legal process is therefore complete. Alt- The main operating plan for the construction of the made by the Luneburg Administrative Appeals Tribunal hough some plaintiffs lodged a constitutional complaint Konrad repository, which is required to carry out work in not to allow any appeals against the planning approval. against the decision of the Federal Administrative Court, addition to the plan approval resolution, was submitted As a result, the rulings passed by the Administrative this was dismissed in part on March 27, 2008. In June by the Federal Office for Radiation Protection on October Appeals Tribunal on March 8, 2006 have therefore 2008 (copy deadline for this brochure) one constitutional 16, 2007, and approved by the Lower Saxony State Office become final and absolute; the plan approval resolution is complaint was still pending. for Mining, Energy and Geology on January 16, 2008. The main operating plan is based on the federal mining law; it authorises the necessary mining work and is therefore a further step towards constructing the Konrad repository.

Photo left: During the 1992 hearing, around 290,000 objections were registered against the repository.

16 4. Surface installations The mines: facts, figures, data.

The Konrad mine lies within the Salzgitter municipal per second. The southern tower houses a cage hoist with boundaries, not far from Salzgitter-Bleckenstedt, bet- a payload of 4.6 tonnes and a velocity of 8 metres per ween Braunschweig and Salzgitter-Lebenstedt. There second with freight load and man-riding. are two mines; Konrad Shaft 1, with 11 hectares of land, Konrad Shaft 1 serves as the air intake air shaft and is lies northwest of the suburb of Salzgitter-Bleckenstedt. accessible through the shaft house. This is where the About 1,500 metres to the south-southwest, in the north- railway wagons run that bring the broken ore to the con- western section of the Salzgitter AG (SZ AG) smeltery area, is the 5.5-hectar site of Konrad Shaft 2. The surface veyor belt, and where material that is to be taken into the installations were erected in the 1960s, either prior to mine is stored. The mine property also houses admini- the shaft being sunk or immediately afterwards. stration, social, dressing room and gatekeeper buildings, storage halls, a cooling tower, and transport hoist and Konrad Shaft 1 is used for man-riding and transporting Photo above: Temporary hoist at Konrad Shaft 2. shaft sinking machinery houses. materials, ore and broken ore above ground. The double A-frame winding gear with the cable wheels lying on top Konrad Shaft 2 serves as the exhaust and so-called and mining facilities were in need of refurbishment. To of each other carries a cage hoist in the northern tower escape shaft in the event that Konrad Shaft 1 is out of ensure the safety of the operations, a temporary hoist with two 3-level cages. The payload is 18 tonnes; the action. The hoist frame and the buildings connected to was installed at the beginning of 2008. velocity with freight load and man-riding is 10 metres it have since been demolished because the mining hoist Photo below: The site at Konrad Shaft 1.

SURFACE INSTALLATIONS 17 5. Geology Konrad: the discovery.

The iron ore bearing layer in the Upper Jurassic was dis- carried out that resulted in a valuable expansion of sci- Underground drift excavation and ore mining began in covered by chance in November 1933 at a depth of 660 entific knowledge. 1960. However, it was not until 1965 that large quantities metres, 5 kilometres south east of Gifhorn in the Vinger- of ore began to be mined. In 1976, production was cea- hoets 4 well, which had been sunk in the search for oil. Iron ore mining sed, as it had become unprofitable. A total of 6.7 million Further drillings followed up until 1936. It was not until From 1937 and 1943, the ore deposits were investigated tonnes of iron ore were mined in Konrad Shaft 1, which 1938 that ore discoveries in two oil prospecting wells led using exploratory drillings before being tapped by sinking is equivalent to only about 0.5% of the entire volume of to the acquisition in the deposits of an iron ore mining shafts 1 and 2 in the Konrad mine between 1957 and 1962. the deposits. field by the then ‘Reichs’ works. From 1939 onwards, the iron ore of the Upper Jurassic around Gifhorn underwent closer examination. Ore discovered in drillings in 1954

led to the award of the Konrad field. The map on page 10 Million Ore-rich System Series Upper deposit years carbonate shows the areas in which the ore was found. Quaternary 1,8

Tertiary 140 Limestone

In addition to these two mines there were also more Cenezoic 65 Tithonian Upper Cretaceous than 90 exposures with a total of approximately 96,000 Cretaceous Portlandian 152,5 Lower Cretaceous 140 Upper Marlstone metres of boreholes. The geological situation around the Malm Kimmeridgian Interburden Jurassic Dogger (local with so-called

Mesozoic Mesozoic Lias Konrad site was well-known due to the iron ore deposit 200 Middle middle deposit) Keuper Oxfordian Iron oolite Triassic Shell Limestone Malm Upper Jurassic (only locally) exposures, the seismic reflection tests and the drillings 251 Buntsandstein 156 oolite Coral Zechstein Oxfordian Lower Perm that were being carried out by the Konrad mine. The Rotliegend 296 Heersum Layers Carbon

findings of geophysical logging, together with analysis oolite Middle coral Limestone marl 358 156 of existing core samples, formed the basis of the assess- Devon 417,5 Silurian ment of the barrier properties of the overlying strata Paleozic 443 made by the Gesellschaft f¸r Strahlen- und Umweltfor- Ordovician Lower deposit 495 Iron oolite schung. Cambrian 545 Following initiation of the plan approval procedure, the

additional investigations indicated in chapter 2 were Stratigraphic sequence of iron ore in the Konrad mine (based on Dr. W. Diem, 1986).

18 W E AG changed over to rich ores and ore concentrates with Height 60% iron content. in m ASL Konrad Shaft 2

Quaternary Geological development 0 Upper Cretaceous The area between the Broistedt-Vechelde, Thiede and, Flachstöckheim salt structures and the Salzgitter ridge

Lower Cretaceous of mountains is characterised by the tectonic activity

Upper Jurassic Middle and Lower Jurassic of the region. This deformation can be characterised by –1,000 Malm the uplift and subsidence of large sections of the Earth’s Dogger crust, which took place slowly over long periods of time, Triassic

Broistedt salt dome Broistedt Ore Lias as well as by the presence of faults.

–2,000 The oldest structural element is the Immendorf Fault, which divided the strongly subsiding eastern massif from the less strongly subsiding western massif in the time 0 2.5 5 6 km extending from the Lower through to Middle Bunter. However, the situation was reversed in the time between Simplified West-East cross-section (A-A’) in the vicinity of Konrad Shaft 2 (for the location of the cross-section, see diagram on page 29). the Upper Bunter through to the Muschelkalk.

The geological structure the iron content of these, however, is less than that of The area around the iron ore deposits does not present a the deeper deposit. uniform tectonic picture, but is a system of rim synclines The repository does not affect economically important of the chain of salt domes including Vorhop, Gifhorn, deposits of raw materials, as the iron deposits in the Rolfsb¸ttel-Wendeburg, Vechelde and Broistedt. middle coral oolite, due to the low average iron content The iron ore deposits in the coral oolite (see diagram on of below 40%, are low-grade ore according to present the left) were created in separate basins to the east and day standards. Mining Konrad ore became uneconomical west of the salt domes. At its maximum expansion, the as international mining switched to deposits that could deepest deposit mined in the Konrad mine followed the be worked in large open pits. Added to this, Salzgitter axis of the rim syncline in Malm-age strata. Overlying the lower deposit is a unit of interbedded mid- to dark gray

mud marlstones. Above this, a 4–10 metre thick unit of Photo right: Work on sinking the shaft for Konrad 1 began in 1957 iron-rich calcareous sediment covers the entire valley; The photo shows the mining frame in 1958.

GEOLOGY 19 Trend reversal: From now on, there was increased sub- the strata within the basin indicate that the movements to almost 400 metres. Additionally, the mine is overlain sidence in the western massif. In the Keuper and Lias along the fault segments took place in the deeper parts by Albian (early Lower Cretaceous) strata to a depth of eras, the fault was active as a result of the pronounced of the Lower Cretaceous section. at least 210 metres in the east, increasing to a maximum subsidence in the western massif, a trend which conti- of 300 metres in the west. The sand horizon at the base nued through to the Dogger era. At the northern end, Geological barriers of the Albian (Hils sandstone) is present only in the area movement ceased during the Lias era and the area was The actual geological barrier to the groundwater close directly above the southern part of the mine where it has tectonically quiescent prior to the marine transgression to the Earth’s surface is the clayey unit of the Lower a maximum thickness of 5 metres. During numerous labo- in the Lower Cretaceous. Cretaceous, which covers a wide area of the trough- ratory tests performed on the petrography, geochemi- The Konrad graben (see diagram on page 21) is bordered shaped Jurassic strata. The barrier formed by the muddy stry, porosity, permeability, sorption behaviour and rock by a fault system, the Bleckstedt Fault in the south and overlying strata increases in thickness from east to west solidity of the drill cores from Konrad 101, scientists have the Sauing Fault in the north. Both faults terminate in corresponding to the dip of the repository formation. verified the good quality of the Lower Cretaceous barrier the west at the Vechelde-Broistedt salt structure, and – In general, it is about 100 metres thicker in the Konrad (shown dark green in the diagrams on pages 19, 20, & 21). in the east – just about where the rim faults meet. Mine graben than south of the Bleckstedt Fault. At no point openings and seismic reflection findings have revealed above the mine is the Lower Cretaceous covering less that the graben did not exist at the time the ore depo- than around 170 metres thick. To the west, it increases sits developed in the Oxfordian. Depth distributions of to around 270 metres, and north of the Bleckstedt Fault

W E Height Konrad Shaft 1 in m ASL (projected)

Quaternary 0 Upper Cretaceous

Lower Cretaceous Vecheide-Broistedt Thiede salt dome salt dome

–1,000 Upper Jurassic Zechstein Zechstein Middle and Lower Jurassic

Fault Triassic Transgression –2,000 Section border Simplified West-East cross-section (B-B’) in the vicinity of Konrad Shaft 1 (for the 0 2.5 5 7.5 9 km location of the cross-section, see diagram on page 29).

20 Sauingen 2 (50 m O’) Schacht Konrad 1 Bleckenstedt 1 (120 m O’) Bleckenstedt 4 (45 m W’) N Salzgitter Zweigkanal S 100 m

NN

–100 m Sauingen 2 (50 m O’) Schacht Konrad 1 Bleckenstedt 1 (120 m O’) Bleckenstedt 4 (45 m W’) –200 m N Salzgitter Zweigkanal S 100 m –300 m

NN –400 m Sauinger Sprung Sauingen 2 (50 m O’) Schacht Konrad 1 Bleckenstedt 1 (120 m O’) Bleckenstedt 4 (45 m W’) –100 m –500 m N Salzgitter Zweigkanal S 100 m –200 m –600 m

NN –300 m –700 m

–100 Sauingenm 2 (50 m O’) Schacht Konrad 1 –400 m Bleckenstedt 1 (120 m O’) Bleckenstedt–800 4 m (45 m W’) Sauinger Sprung N Salzgitter Zweigkanal S Konrad-Graben Bleckenstedter Sprung –200 m –500 m –900 m 100 m –300 m –600 m –1,000 m NN –400 m –700 m –1,100 m –100 m Sauinger Sprung –1,200 m W –500 m Konrad Shaft 2 Konrad 101 –800 m E –200 m 0 100 m Hallendorf 1 (projected, 550 m N’) (approx. 500 m N’) Konrad-Graben Salzgitter canal branch–600 m –900 m Bleckenstedter Sprung –300 m 100 m –700 m –1,000 m Quaternary Malm: Mund Mergel, Gigas layers Fault Drilling –400 m NN Sauinger Sprung Upper Cretaceous Malm: Kimmeridgian Section –800 m –1,100 m –500 m border –100 m Lower Cretaceous: Albian with Hils sandstone Malm: Oxfordian with coral oolite and ore deposit Mine, drift, Konrad-Graben Bleckenstedter Sprung –900 m –1,200 m Cross section through the drift –600 m Lower Cretaceous: Dogger –200 m 0 100 m Aptian, Barremian, Hauterivian –1,000 m –700 m –300 m –1,100 m Quaternary Malm: Mund Mergel, Gigas layers Fault Drilling –800 m –400 m Upper Cretaceous Malm: Kimmeridgian Section –1,200 m Konrad-Graben –900 m Bleckenstedter Sprung border –500 m 0 100 m Lower Cretaceous: Albian with Hils sandstone Malm: Oxfordian with coral oolite and ore deposit Mine, drift, –1,000 m Lower Cretaceous: Dogger Cross section through the drift –600 m Aptian, Barremian, Hauterivian Quaternary Malm: Mund Mergel, Gigas layers Fault Drilling –1,100 m –700 m Upper Cretaceous Malm: Kimmeridgian Section –1,200 m border –800 m Lower Cretaceous: Albian with Hils sandstone Malm: Oxfordian with coral oolite and ore deposit Mine, drift, 0 100 m Lower Cretaceous: Dogger Cross section through the drift –900 m Aptian, Barremian, Hauterivian Geological West-East cross-section (C-C’) approx. 500 metres south Fault Drilling –1,000 m Quaternary Malm: Mund Mergel, Gigas layers Upper Cretaceous Malm: Kimmeridgian of Konrad Shaft 2 (for the location Section –1,100 m 0 100 m Lower Cretaceous: Albian with Hils sandstone Malm: Oxfordian with coralof the oolite cross-section, and ore deposit see diagram onborder Mine, drift, –1,200 m Lower Cretaceous: Dogger page 29). Cross section through the drift Aptian, Barremian, Hauterivian

Sauing 2 (50 m E’) Konrad Shaft 1 Bleckenstedt 1 (120 m E’) Bleckenstedt 4 (45 m W’) N Salzgitter canal branch S 100 m

NN

–100 m

–200 m

–300 m

–400 m Sauing Fault –500 m

–600 m

–700 m

–800 m Konrad Graben –900 m Bleckenstedt Fault

–1.000 m

–1.100 m Geological North-South cross-section (D-D’) –1.200 m through Konrad Shaft 1 (for the location of 0 100 m the cross-section, see diagram on page 29).

Quartär Malm: Münder Mergel, Gigas-Schichten Störung Bohrung Oberkreide Malm: Kimmeridgium Schichtgrenze Unterkreide: Albium mit Hilssandstein Malm: Oxfordium mit Korallenoolith und Erzlager Schacht, Strecke, GEOLOGY 21 Unterkreide: Dogger Streckenquerschnitt Aptium, Barremium, Hauterivium 6. Mine Underground: from ore mine to repository.

In the period from September 18, 1957 to January 30, descent was continued in the line of bearing of the depo- A new method of excavation 1960, Konrad Shaft 1 was sunk to a depth of 1,232.50 sit reaching the deposit that had been displaced by the The excavation method proved to be too complicated for metres. Transitional areas (pit eyes) were created bet- Bleckstedt Fault by the shortest route. Between October the large, uncontrollable excavation areas. In developing ween the shaft and the mine at 1,000 metres (third level); 1962 and January 1963, a crossway was driven from here a new excavating method, the choice fell upon a method at 1,100 metres (fourth level) and at 1,200 metres (fifth between the shafts of Konrad 1 and Konrad 2. By directly using rubber-tyre, rail-less large-scale diesel machines, level). Ore deposits were found between 1,150.50 metres connecting the two shafts at one continuous level the drilling jumbos, excavator and auxiliary vehicles. To the and 1,184.90 metres. Work on sinking Konrad Shaft 2 quality of the air could be improved considerably. south of the main ramp, between the 1,100-metre and the started on March1, 1960 and was completed at a final For excavation purposes, the 1,000-metre and the 1,100- 1,000-metre levels, the previous method of excavation depth of 999 metres on October 31, 1962. One pit eye metre levels were connected to each other in the gra- was replaced in 1971 by this more conventional, advance was abandoned at 983 metres (third level). The clear dient of the ore deposit, and excavation routes in the LHD-method for road pillar mining. Backfilling the diameter of both shafts is 7 metres. line of bearing divided the deposit into three sections. In excavated chambers was dispensed with. Instead, to The mine layout mainly follows the largest depth of the 1965, ore mining with hydraulic backfill was begun in this secure the overlying strata, strong pillars were left body of ore to over 1,200 metres. Other defining factors, chamber. standing between the excavated areas. The horizontal however, were the thickness of 12 to 18 metres, the gra- This procedure involved creating a 5-metre diameter caverns had a cross-section of approximately 30 square dient of between 20 and 22 degrees in the central area, connection between the intermediate levels, and linking metres and were accessed via spiral or diagonal entran- and the tectonic conditions. As a matter of principle, the the connection to the upper intermediate level by drilling ces from numerous intermediate levels. The new excava- high temperature of 40 to 49 degrees Celsius at this and blasting a funnel-shaped extension. The excavated ting method proved to be more efficient and economical depth required an efficient supply system for fresh air. ore was transported from the chamber to the lower drift within a relatively short space of time, and, in 1973, the where it was broken up before being transported to Kon- maximum annual conveyance was more than 700,000 The beginnings rad Shaft 1. tonnes.

In September 1960, the first drift excavation began from Between 8,000 and 14,000 tonnes of ore were taken It also became possible to construct stable areas with Konrad Shaft 1 to the 1,200-metre level, from which the from each of the chambers. The caverns were not lined large cross-sections in the ore deposits. This is important first ore was mined from December 1960 onwards. At and it was forbidden to enter them; the mined areas were if this type of cavern is to be used to dispose of radioac- the beginning of 1961, the 1,100-metre level was exca- filled with hydraulic backfill (a mixture of sand, gravel and tive waste. vated in a south-easterly direction and reached the ore water). The area above the 1,000-metre level was also deposit after descending 210 metres to the south. The excavated by the same method.

22 Photo below: Drilling the blast hole with a pneumatic drill advancing at the 1,000-metre level in September 1962.

Photo right: Today heading is done with the road header.

Mine 23 The end of excavations ways and ramps to ensure the safety of the mine. About metres was completed by 1980. In order to increase the Despite the substantially reduced operating costs, in 150,000 tonnes of ore were still mined in this period overall cross-section to 40 square metres, the floor level the long run this method also proved to be unprofita- (1977 to 1982). was re-cut. The ventilation test track has a terminating wall for, in particular, conducting rock mechanics tests ble, and production was ultimately ceased in October In 1978, work was begun on behalf of the Gesellschaft and permeability measurements. 1976. Following the cessation of ore production, some f¸r Strahlenforschung on the exploratory drift that came of the remaining workforce continued working for the to be known as the “ventilation test track”. The first On a further level, between the 1,100-metre level and Gesellschaft f¸r Strahlen- und Umweltforschung. Repair 88 metres were excavated below the 1,200-metre level the 1,200-metre level, drift excavation with mechanical and maintenance work was also carried out on the road- using blasting techniques, and the entire length of 202 heading was attempted using a road header, the advance being carried out in two phases.

In the first of these, the crown of the roadway – i.e. the N Konrad Shaft 1 (+98.5 m NN) Konrad Shaft 2 (+90.2 m NN) S upper section, with a cross-section of 25 square metres – was excavated. Phase two extended the roadway pro- file by re-cutting the level to 40 square metres in all. A NN Intake Air Exhaust Air diagram of the mine is shown on page 24.

–100 m Underground exploration –200 m From 1982, the Physikalisch-Technische Bundesanstalt –300 m continued a site exploration programme with the aim of

–400 m providing a comprehensive safety certificate and supple- menting the plan on the basis of the ‘safety criteria for –500 m the disposal of radioactive waste’ given out by the German –600 m Ministry for the Interior. The future disposal areas were 800-metre level Level 1 –700 m therefore circumnavigated by roadways and explored with 850-metre level Level 2 drillings. –800 m East Ramp South Ramp The exploration included principally –900 m 1,000-metre level Level 3 South Spiral the excavation of investigation roadways on the –1,000 m 1,100-metre level Level 4 800-metre level as well as the 1,300-metre level to –1,100 m 1,200-metre level Level 5 the outer rim of the intended repository fields south North Ramp –1,200 m 1,300-metre level Level 6 of the Bleckenstedt Fault;

the eastern extension of the cross-shaft level at the Diagram showing the two shafts of the Konrad mine. 1,000-metre level of Konrad Shaft 1 in order to

24 explore the deposit conditions to the north of the Bleckenstedt Fault; and

the excavation of a ramp above the 1,100-metre level.

During these explorations and as a result of maintenance work that needed to be carried out, from 1982 to 1988 around 1.35 million tonnes of broken ore was conveyed: Some of the ore was smelted, the rest was stored in the former open pits at Vallstedt und Haverlahwiese. Salzgitter- Since 1985, further technical data and empirical values Bleckenstedt Field 5a required for detailed planning of the mine have been gained from the excavations of various drifts; mainte- nance work required to keep the mine workings open has also been continued.

In addition, the ends of the excavated exploration road- ways were, as far as possible, also linked to the other wor- kings to create through ventilation. Finally, excavations Konrad that had not been backfilled were sealed to minimise Shaft 2 radon radiation, and the usual maintenance operations were carried out in the mine. (For further information on this subject: see also page 50 under ‘radiation exposure of personnel’).

Sub-field 5.2 Field 5 Sub-field 5.1

Salzgitter Photo left: Map showing where the disposal chambers will be excavated on the 800-metre Harbour level and the 850-metre level of the fields marked 5 and 5a. As things stand today, these will be large enough to store the radioactive waste.

mine 25 7. Planned repository mine Field 5: the prerequisites.

Following the achievement of the non-appealability of The return air collection drift that is con- Max. length 800 metres the plan approval resolution (March 26, 2007), and the nected to the main air collection drift

license for the main operating plan (January 16, 2008), (cross-section about 20 square Max. length 800 metres Max. length 800 metres Container storage excavations for the main disposal chambers can now Return air metres) will be connected collection drift

Returning air Round package storage Max. length 800 metres begin. Several disposal chambers make up a disposal via large boreholes to the Creation of a backfill wall Unload chamber field. It is anticipated that Fields 5 and 5a will be suffici- entrance area of the Paste backfill (thick matter) Min. 10 metres ent (see the relevant diagram on page 25). The disposal respective disposal 3 2 chambers will be constructed with a cross-section of chamber. In Max. length 800 metres 1 Filled storage chamber (thick matter) about 40 square metres with a floor level width of 7 this way 1 Evacuation chamber 2 Backfill transport vehicle metres and a height of 6 metres, and be excavated to a built- 3Spray manipulator vehicle

Cemented backfill (thick matter) the same level. in aerator with

The permitted deviation from the longitudinal gradient is auxiliary exhaust Storage transport section a maximum of 2.5%, the ratio between the pillar width to ventilation can ensure the chamber or roadway width is normally 4:1 between aeration during storage. neighbouring chambers and other roadways in the dis-

posal field. The result is an overall pillar thickness of 28 The disposal fields Diagram of the repository chambers of metres. By contrast, the ratio between chambers and the Storage will begin in Field 5 (Sub-field 5.1). This will be a disposal field. top or bottom roadways is 5:1, which is equivalent to a prepared during the construction phase. This means that pillar width of about 35 metres. south of Konrad Shaft 2, between the 850-metre level sub-field, has been completely excavated. Nine disposal

The disposal chambers are accessed via a ramp or spi- and the 800-metre level, six disposal chambers will be fields have been authorised, against the background of ral route over a chamber approach that is at least 35 constructed plus the associated unloading chambers, the the 600,000 cubic metres of storage volume originally metres long – the cross-section of the chamber approach return air collection drifts and the return air boreholes. applied for. In all probability, however, Fields 5 and 5a will is around 25 square metres. At the crossover to the dis- Apart from this, the cross-section of the 800-metre suffice because new conditioning methods will enable the posal chamber, one unloading chamber will be excavated level is to be extended to the south from about 28 to volume of waste to be reduced to 280,000 cubic metres per disposal field, and above the chamber approaches approx. 40 square metres. Storage will begin when the as things stand today. usually one return air collection drift per field. respective field, or a controlled area of a separable

26 8. Hydrogeology Water: the repository keeps (water) tight.

In the deep geological strata within which the Konrad topmost groundwater storey and the radioactive waste transport of radionuclides was assessed on a north-south repository is located, permeable alternates with low- that is to be deposited there in the future. Artifi­cially oriented, approximately 14-kilometre wide and 40-kilo- permeable or even impermeable layers. Thus the ground- constructed connections, such as earlier prospective metre long strip (see diagram on page 28). Exemplary water body is subdivided into a series of so-called drillings for iron ore or oil, have been hydraulically estimates of groundwater movement, i.e. current path groundwater storeys, which differ from one another in filled to seal them up. Following the end of operations, and current time of the groundwater, were also simulated terms of hydraulic behaviour. The groundwater close both shafts of the repository mine will also be hydrauli- in model calculations. to the surface, which is influenced locally by people is cally sealed. mainly found in the sandy sediments of the quaternary Conservative approach and is hydraulically connected to local bodies of water. Hydraulic connections For the purpose of the model calculations the geological Below a depth of around 150 metres, groundwater con- Tectonic faults and fault zones play only minor roles as and hydrological conditions were presented in both sim- tains considerable amounts of dissolved substances (salt hydraulic connections between aquifers that are sepa- plified and conservative modes. The principle behind the content > 1 gramme per litre) therefore becoming increa- rate from each other. In water conducting joints discove- conservative approach is to prove the long-term safety singly more dense and possessing slow to negligible flow red during excavations for new mines or when drilling in of the site while taking unfavourable conditions and velocities. the coral oolite (the storage horizon of radioactive waste) processes into account. This means that processes that waterfill is usually reduced fully within a very short time. could, for example, accelerate dispersion of the radionu- Water conductivity of the strata There are no extensive hydraulically effective joints in clides, are considered in the model calculation, whereas The lower groundwater storeys consist of single, low- the area of the mine. Any water conducting joints, which other processes that impede or slow dispersion are only depth, permeable layers, which are separated by thick were discovered in the vicinity of larger faults – such as partially or marginally considered. layers of low permeability mud. This system of permeable at the Beckstedt Fault – dried up within a very short time. and low-permeable layers is hydraulically limited down- Conservative assumptions for Konrad wards by the salt layers of the Middle Muschelkalk and Model calculations No indication of any natural groundwater movement was laterally by the salt beds. Hydrochemical and isotopic In the course of long-term safety certification, despite found in the deep, permeable layers in the vicinity of the chemical tests have revealed that since the time of origin the fact that investigations had shown that the formation repository. For the conservative reasons given above, it is of the rocks the deep waters have not been involved in the water in the host rock would remain there for a long time assumed that some contaminants from the waste stored groundwater cycle and are therefore so-called for-mation (see also chapter 16), model calculations were carried in the Konrad repository will enter the biosphere via the waters. In the area around the Konrad repository there out for the transport of radionuclides from the reposi- groundwater. Only the natural barriers of the geosphere are no direct natural hydraulic connections between the tory area into the biosphere. The impact of an envisaged are able to delay this process. The assumed movement

ENVISAGED REPOSITORY MINE/HYDROGEOLOGY 27 of the formation water in the deeper water storeys, and realistic annual rate of erosion of 0.1 millimetre (mm/a), Water during and following operation time therefore through the storage area, is based on a hydrau- the Salzgitter range of mountains would cease to exist in When the repository is in operation, the likelihood of lic incline (potential) that originates at the elevations of about 1 million years. In the geologically short time frame uncontrollable water entry, for example during excava- the Salzgitter mountain ridge. It is at this point that deep of 3,000 to 10,000 years, climate changes are also to be tion work in the disposal chambers, can be excluded on bedrock makes contact with the Earth’s surface, which expected, so that these boundary conditions can only be the basis of known volume of water that has entered the could facilitate the creation of a hydraulically effective deemed reliable for a maximum of 10,000 years. mine previously. In the phase following the operation, the connection to the radioactive waste storage area. How remaining cavity space in the repository will gradually fill In the model, the formation water basically flows from much this hydraulic potential will affect the deep under- with water. Natural cavities (rock pores, rock fractures) the water-conducting layers in the Triassic that are ground and how acutely it will lead to the movement of in the immediate vicinity will become saturated with located below the radioactive waste storage area, into formation waters to the north, depends on the hydraulic water again, so that the natural condition of the ground- the waste storage area. This migration is strongly inhi- features and storage conditions of the layers, as well water prior to the excavations for the Konrad site will bited by Jurassic mudstone. Due to the fact that the as on the saline content and density of the formation eventually be reinstated. The original rock pressure con- thick mudstone layer of the Lower Cretaceous acts as waters. ditions, however, will, for the most part, not return for a an upward seal, there are only minimal possible natural further 2,000 years. Before this occurs, there can be no In the model calculation, these conditions are the pathways to the groundwater conducting layers that are theoretical transport of radionuclides to the surface. boundary conditions and as such, kept constant. With a close to the Earth’s surface.

Theoretical diffusion path of the water SW NE Parameter studies were carried out to calculate the theoretically possible movement of formation waters. Salzgitter Salder Groß Watenbüttel, Schwülper Adenbüttel Röttgesbüttel Calberlah Different parameter variations were used to examine mountain Heerte Konrad Gleidingen Wendeburg ridge Shaft 1 Break in the Break in the Break in the Break in the Break in the the different connections between layers of rock and the m NN section section section section section Quaternary Quaternary influence of tectonic faults. It has been shown that with 0 1 2 Ia Cretaceous conservative model assumptions (including freshwater as –1.000 Ib formation water instead of saltwater, which has a grea- Ic ter density) water paths that originate at the repository –2.000 Jurassic Triassic reach different points of the biosphere depending on the Albian/Hils sandstone Malm/Oxfordian with coral oolite Dogger/Cornbrash sandstone rate of permeability assumed for the Lower Cretaceous. 0 5 10 20 30 40 45 km

Section is double depth. Section border Modelled aquifer in the Cretaceous Ia Lower Cretaceous path

1 Bleckenstedt Fault Fault Modelled aquifer in the Jurassic Ib Oxford path 2 Sauing Fault Repository Modelled aquifer in the Triassic Ic Cornbrash path

Cross-section (E-E’) through the area of the model showing the model of the diffusion paths.

28 Path 1a Evaluation of results Key The theoretical diffusion of the formation water through In the model calculations, the radionuclides Aller THIEDE Gifhorn the mudstone of the Lower Cretaceous occurs when a will reach the biosphere from the reposi- Salt structure N Motorway Leiferde E’ relatively high degree of permeability is assumed for this tory at differing times depending on the Calberlah Flowing waters, canal Oker thick, clayey geological barrier. Radionuclide-laden water assumed diffusion path. These effects are Wolfsburg Section boundary from the storage area in the vicinity of Groß Gleidingen described and evaluated in chapter 16. The Drilling (between Salzgitter and Braunschweig) will reach the different results of the calculations are Mine

biosphere following a minimum period of 430,000 years Midland Canal based on the movement of the formation 0 5 10 km (path 1a). water assumed in the model, as well as on

further conservative assumptions, inclu- Peine A 2 A 2

Path 1b Salzgitter canal branch ding the rates of hydraulic permeability in A theoretical diffusion of the formation water through the mudstones. There is no diffusion of for- the rock layers of the Oxfordian occurs when a realistic A 39 mation waters from the storage area into A391 Braunschweig degree of permeability is assumed for the thick, clayey the biosphere in those model calculations geological barrier of the Lower Cretaceous. The diffusion with increased-density saline groundwater, Groß Gleidingen path of 33 kilometres is considerably longer. The bios-

VECHELDE such as is present at the Konrad mine site. Lengede A 39 phere in the vicinity of Calberlah (between Gifhorn and B A 39 E–E’ Wolfsburg) will be reached after a minimum period of Broistedt SZ-Thiede B’ D 300,000 years (path 1b). BROISTEDTA A’ SZ-Lebenstedt B–B’ Sauingen 2 THIEDE SZ-Watenstedt Konrad Shaft 1 Path 1c

A theoretical diffusion of the formation water through Bleckenstedt 1 E SALZGITTER Konrad Shaft 2 the Cornbrash, a permeable layer of sandstone in the Innerste Bleckenstedt 4 Jurassic, also occurs when a realistic degree of permea- Area of the model A–A’ Konrad 101 C C’ bility is assumed for the thick, clayey geological barrier Hallendorf 1 A7 D’ of the Lower Cretaceous. A small amount of the water Salzgitter Bad 0 1 km

Salzgitter Harbour that moves through the radioactive waste storage area Map showing the location of the model area and geological cross-sections. will reach the Cornbrash through the mudstone of the Dogger. This will take about 1.1 million years, mainly due to the low velocity rate through the muds of the Dogger (path c).

HYDROGEOLOGY 29 8° E 9° E 10° E 11°E 12° E 13° E 55° N 55° N Damage-inducing earth- quakes, 800 to 2007

6.5 –< I0 < 7.5 7.5 < I < 8.5 9. Rock mechanics and seismology – 0 8.5 –< I0 < 9.5 Tect. Earth- Non- quakes tect. Federal Office for Radiation Protection The future: predictably safe. 54° N 54° N

The Konrad site is situated in a geologically quiet zone The assessment of rock mechanics Hamburg of Germany. The last tectonic movements in the area of The assessment of the rock mechanics of the Konrad

the site took place about 5 million years ago. It is not mine is based on numerous measurements and obser- Bremen 53° N 53° N expected that such movements will be intensified – as for vations, as well as on mining experience. Subsidence example could happen in the case of earthquakes – in the damage on the surface has not occurred to date and, Berlin course of the next millennia. based on the experience gathered with cavity excava- Hannover tions, is not expected to occur in the future. Depending Konrad Wolfenbüttel Since 1323, there have been fewer than 10 tectonic 52° N Münster 52° N on the number and size of underground cavities, different damage-inducing earthquakes within a 200-kilometre sized convergences occur in the immediate aftermath of radius of Konrad. Bochum Göttingen cavity construction, which decrease logarithmically over time. In the past, the excavation regulations developed 51° N 51° N Earthquakes in the Konrad area for working the Konrad mine had proved effective. There The epicentres of these quakes are shown in the adjacent are no doubts concerning the structural safety of the

diagram. The long distances to the Konrad site illustrate Konrad mine in its present state. Model calculations of Hof

the low seismicity of the area surroundings the site. In the rock mechanics, together with mining experience, Frankfurt am Main 50° N 50° N the past 1,200 years, no earthquakes resulting in damage give rise to the assumption that there will be no damage 8° E 9° E 10° E 11° E 12° E 13° E

were recorded in the 100-kilometre area around the site. to surface installations following construction of the Damage-inducing earthquakes in the vicinity of the Konrad site. The locations of the historical, damage-inducing earth- Konrad repository, and that the effects on the shafts will Each circle represents a 50-kilometre interval. quakes, which are shown in the diagram, indicate focal be minimal and not capable of endangering the structural safety. The deformation history of the overlying strata areas in the Rhine Valley, in Saxony and in the German- Behaviour of rock mechanics following backfill exhibits a decreasing tendency. In view of the relevant Czech border area. The tectonic conditions there are not Following the operation phase, the storage areas of the geological conditions and the planned ratio between the comparable with those at the Konrad site. Only one earth- repository will be loaded with backfill. The shafts will also width of the mine opening and the thickness of the pillar, quake with resulting damage has been recorded within be closed off following shutdown. This means that the the bearing capacity of the pillars is ensured. a 150-kilometre radius. In the investigations into the mechanical behaviour of the once open areas will again likelihood of earthquakes, all events with intervals up to Modern technology has been applied to ensure that repo- conform to that of the adjoining rocks. As there will be 200 kilometres around the Konrad site were taken into sitory buildings, machines, electronic components and no more open excavations in the post-operational period, account. shafts can withstand earthquakes. there is no likelihood of a noticeable collapse.

30 10. Long-term geological prognosis Calculations: the prospects are good.

Predictions about possible future geological events are based on knowledge of the events that have occurred in the geological past up to the present day. Those geologi- cal events will be investigated from which it is thought, due to the possibility of their future occurrence or the current state of the developments at the Konrad site, that they could affect the safety of the repository.

Ice ages There have been a number of ice ages in the course of the Earth’s history, each of which lasted up to several million years. There were three to four cold periods in Northern and Central Europe, each lasting about 100,000 years; these were interrupted by warm periods lasting between 10,000 and 30,000 years. We are presently living in a warm period, the Holocene, which began around 10,000 years ago and crossed its temperature optimum around 4,500 years ago. From the climatic standpoint, there- fore, a new cold period should begin in a few to ten thou- sand years from now.

During those periods when the ground is frozen, such as in present-day Alaska and the Siberian Tundra, the geolo- gical barrier can only be influenced by frost that reaches 100 – 200 metres down into the deeper underground. However, in Northern Germany groundwater salination, Exemplary depiction of how ice spread throughout Northern Europe which effects a lowering of the freezing point, sets in during the penultimate cold period (source: Meschede).

ROCK MECHANICS AND SEISMOLOGY/LONG-TERM GEOLOGICAL PROGNOSIS 31 at a depth of about 130 to 170 metres. When the ground particularly of the muddy Lower Cretaceous strata, to tribution, nor by the thickness or the physical-chemical freezes to a great depth, this affects both the hydrologi- swell and expand would also have a sealing effect. behaviour of the barrier rocks of the muddy Lower Cre- cal conditions and the mechanical behaviour of the rock. taceous. It is theoretically possible that the weight of the ice Groundwater becomes immobile due both to the lack of could accelerate compaction of the barrier layers. In the Warming and a shift of the climate zones due to anthro- rain and the inability of water to penetrate the ice-filled process, the low strength marl and mud marlstone could pogenic influences (global warming) will essentially only underground pores and fissures. Changes to the features attain greater strength and demonstrate greater brittle have an effect on the hydrological conditions. of the underground rock barrier will therefore be mini- fracture behaviour. In the geological past, the area around mal. Rock disruption or the expansion of existing fissures the Konrad site had already been burdened with ice can only occur as a result of frost pressure, which could masses and additional rock, which has now either melted A dryer climate, or higher rates of groundwater evapo- result in increased permeability when the ground thaws or been eroded, so that significant compaction can only be ration, results in a lower rate of new groundwater pro- again. However, these processes are only to be expected caused by a higher burden than that already experienced. duction and causes groundwater movement to decele- in the upper regions because increasing rock pressure There is little likelihood of this happening in the fore- rate. Higher annual global temperatures would release will exert corresponding counter pressure, which the ice seeable future. those water masses presently contained in the continen- will try to avoid with flow deformations. During the last tal ice shelf causing the sea to rise by around 75 metres. There would be no significant change to aquifers close to ice age, the creation of huge ice masses caused the level Effects on the area around Konrad the surface, but as a result of the altered pressure condi- of the sea to sink by more than 100 metres. In spite of Initially, the glacial advance would remove up to a tions it is assumed that the deeper groundwater storeys this, there was no appreciable increase in the eroding few tens of metres of bedrock over an extensive area, would demonstrate slower flow velocities. function of the rivers flowing into the North Sea, as the whereby the resulting rubble would be found in the river gradients remained largely unchanged due to the ground and terminal moraines. The ice, either alone or in uniformity of the North Sea basin. combination meltwaters, could also create local forma- tions of deeper cavities (subglacial channels, terminal Ice masses in Germany basin lakes). It has been found that there are quaternary The most striking feature of the cold periods was the depressions up to about 100 metres under the surface advance of huge ice masses from the far north into in the area around the Konrad mine. However, some of Northern Germany (see adjacent diagram), even reaching these could also be interpreted as sub-erosional depres- as far as the Central German Uplands. The weight of sions above the adjacent salt domes. Subglacial channels the ice caused both widespread and local rock pressure with a depth of more than 200 metres below zero can changes and deformations, which, under certain con- only be found north of a Gifhorn–Celle–Delmenhorst line. ditions, could cause a loss in strength of the rocks. This At no point, however, were deep incisions of such cavities does not necessarily result in the creation of open faults, into bedrock observed. Thus, due to the depth location of in which water could circulate, but chiefly in the creation the storage facilities for radioactive waste, the Konrad Photo right: Salt structures in Northern Germany. of shear planes. The capacity of the geological barrier, repository is endangered neither by the extensive dis- Source © BGR, Hannover 2006.

32 Salt structures (perm) salt dome salt pillow 0 20 40 60 80 100

km

LONG-TERM GEOLOGICAL PROGNOSIS 33 Erosion and extensive upheavals strength and immobile remains of both the Zechstein salt Year Latitude (°) Longitude (°) Intensity (MSK) distance (km) The erosion of rock and soil in flat and hilly areas is mainly deposits and of the approximately 100-metre thick salt caused by the transport mediums water, air and ice, deposits of the Upper Buntstein and the Middle Muschel- 1323 51.18 12.56 6.5 185 1326 50.80 12.20 6.5 197 whereby in Northern Germany the latter was only kalk, which show no sign of salt movement. Because of 1346 50.80 12.20 8.0 197 effective during the ice age. the low rate of upheaval of the salt domes in the area 1366 50.80 12.20 7.5 197 around the Konrad repository, no further significant If an annual erosion rate of 0.1 millimetres is assumed, 1578 50.88 12.23 6.5 192 deformations of the overlying strata, which could inhibit 1598 50.87 12.18 6.5 190 which would be relatively high for Northern Germany, and the effectivity of the geological barrier are expected in 1711 51.18 12.56 6.5 185 extrapolated to 100,000 years, a 10-metre thick layer the next millennia. 1767 51.00 9.70 6.5 140 would be eroded during that time. Erosion can take place 1872 50.86 12.28 7.5 196 Tectonic earthquakes resulting in damage within a 200-kilometre down to sea level, whereby the rate of extensive erosion Due to the solubility of the halites, salt domes are vulne- radius of the Konrad site. would continually decrease due to the fact that the rock rable to sub-erosion, especially if they rise to the Earth’s and soil layer diminish in the course of the erosion pro- surface and are covered by permeable, water conducting younger geological past (e.g. Eifel, East Sudetes), which cess. The rate of erosion could only be maintained as a sediment. From the long-term geological perspective it were active about 10,000 years ago. Volcanic activity result of upheavals in the region around the Konrad site, is assumed that the balance will be maintained between in the vicinity of the Konrad site ceased several million which will, however, not take place. subrosion and the rise of the salt dome. Widespread years ago. There is no indication of abnormal heat flow With an assumed extensive annual upheaval rate of 0.1 upheaval of the entire region, with corresponding exten- conditions or strong pressure build-ups in the rocks of millimetres, the terrain would rise by 100 metres in one sive erosion, could increase subrosion. It is unlikely that the Earth’s surface, so that neither volcanic activity, million years. Erosion on a comparable scale would first cavities will be created if the loss of salt substance is nor earthquakes that are unusually strong for the region approach the geological barrier of the muddy rock of the compensated by a corresponding rate of upheaval by the are to be expected in the coming one hundred thousand Lower Cretaceous above the repository, at depths of well salt dome. If a high and long lasting annual deposition years. over 100 metres and at a considerably later point in time. rate of 0.1 millimetres were to be assumed, there would be a 100-metre thick loss of salt in one million years. With Impact of adjacent salt structures the actual deposition rates that are possible, the current The Konrad mine is situated between the Broistedt- general hydrological situation will be maintained. Vechelde salt structures to the west and the Thiede salt

dome to the east (see diagram page 29). Earthquakes and volcanism The development of these salt domes was more or less The Konrad site is situated more than 100 kilometres completed in the Late Cretaceous period. The rate of from those areas of Central Europe that are connected upheaval in the phase following the creation of the salt to the fault zones in the Earth’s surface, such as the dome was a few hundredths of a millimetre per year. Lower Rhine Bight or the Upper Rhine Valley graben. It is Below the planned repository there are only a few low also equally as far from areas of volcanic activity of the

34 11. Radioactive waste Forschungs- einrichtungen 44 %

Kerntechnische Distinguishing feature: heat generation.Industrie 7 %

Wiederaufarbeitung In Germany, radioactive waste is produced by The heat generating radioactive waste includes,Karlsruhe in16 %par- usage, is classified as radioactive waste with negligible

ticular, the fission product solutions, the capsules and heat generation. This includes, for example, disused nuclear power stations during operations, structural components and the feed clearing sludge from parts of facilities and defective components such as decommissioning and dismantling nuclear power reprocessing spent fuel elements, as wellKernkraftwerke, as the actual pumps or pipes, ion exchange resins and air filters from stations; research, demonstration and teaching stillgelegt, 12 % fuel elements if they are to be stored as radioactive wastewater and air purification, contaminated tools, pro- reactors as well as other nuclear facilities, Landessammel- waste. stellen 4 % tective clothing, decontamination and cleaning agents, basic research and applied research, davon Medizin laboratory waste, contained sources of radiation, sludge, Waste with considerably lower activity concentrations(Lagerung in Landessammel- suspensions or oils. using radioisotopes in other research institutions, from the operation and decommissioning/dismantlingstellen) < 0,5 % of universities, commercial and industrial operations, nuclear plants and facilities, as well as fromKernkraftwerke, radioisotope hospitals and doctors’ surgeries in Betrieb, 17 %

uranium enrichment and the production of fuel elements (nuclear industry) and Nuclear power other waste-generating bodies such as the military. plants (Utilities) 58 % Konrad in depth In addition, there are also contracts with the nuclear fuel State collecting reprocessing firms COGEMA (now AREVA-NC) in France depots 2.5 % of which medicine Low, intermediate and high radioactive waste and BNLF (now Sellafield Ltd.) in the UK, to dispose of (storage in state collecting depots) The subdivision of radioactive waste into low, the radioactive waste produced in reprocessing spent < 0.5 % intermediate and high radioactive is a qualita- fuel elements from German light water reactors. German Nuclear industry experts categorise all radioactive waste either as heat 4.5 % tive differentiation made primarily for waste- generating waste, or as waste with a negligible heat Public authorities handling and processing purposes. Classification (inc. demolition of generation. research reactors is based on the measures required to protect and of reactors in former East against the ionising radiation. For example, low- At the international level, radioactive waste is subdivided Germany) 35 % level into low, intermediate and high levels. In accordance with radioactive waste is waste with low radionuclide this classification, the waste to be disposed of in the Forecast of the accrual of conditioned waste with negligible heat content, which requires no shield during handling Konrad repository is low and intermediate level radioac- generation in 2040 (accumulated), total volume: approx. 280,000 tive waste. cubic metres. (as of March 2006)

RADIOACTIVE WASTE 35 Disposal to date industry will be conditioned to a standard sui-

SWR The Konrad repository will be used exclusively for the table for disposal and temporarily stored in SCHLESWIG-HOLSTEIN Greifswald/Rubenow DWR DWR DWR DWR DWR DWR disposal of radioactive waste with negligible heat gene- either the waste depot in Gorleben or the 806 Brunsbüttel Brokdorf 1,480 ration. Up to the end of 1978, in a test and demonstration Nuclear Cargo + Service (NCS) interim sto- DWR 440 each HAMBURG Stade SWR MECKLENBURG-WESTERN programme, the former West German states disposed of rage depot in Hanau. POMERANIA 672 Geesthacht Krümmel Unterweser DWR low and intermediate level radioactive waste in the Asse DWR 1,402 In order to ensure safe interim storage 15.0 5.0 Rheinsberg BREMEN mine. In the GDR, this waste was disposed of in the repo- Munster Gorleben 70 and disposal of radioactive waste, it 1,410 sitory for radioactive waste in Morsleben (ERAM), which SWR DWR is necessary for it to be conditioned LOWER SAXONY Leese was taken over by the Federal Office for Radiation Pro- 252 1,400 BERLIN (processed and/or packed). There Lingen DWR 1.0 10.0 tection in the aftermath of German reunification. From Grohnde Braunschweig are a number of tried-and-tested Gronau Morsleben 1,430 Salzgitter 1994 to September 1998, it served as a repository for low processes and facilities available Ahaus Asse BRANDENBURG HTR and intermediate level radioactive waste from the whole for this. SWR SAXONY- Hamm-Uentrop ANHALT of Germany. As no repository is currently available, radi- 308 Würgassen 670 Following collection and NORTH RHINE WESTFALIA oactive waste is being temporarily stored aboveground in separation, the raw waste HTR SAXONY appropriately licensed interim storage depots. Rossendorf/ can first be pre-treated to 15 10.0 23.0 HESSE Dresden 10.0 reduce its volume and then Jülich THURINGIA Ebsdorfergrund Prior to disposal processed into intermediate DWR products. Mülheim-Kärlich Radioactive waste from operating and from decommis- 1,302 SWR sioning and/or dismantling nuclear power stations will RHINELAND- PALATINATE Hanau Kahl DWR Mitterteich Mainz 16 Nuclear power plant; figures: DWR DWR be temporarily maintained in interim storage facilities, gross output in MWe Grafen- rheinfeld Biblis 1,345 Research reactor; figures: thermal output Ellweiler 0.1 which will be constructed and operated by the opera- in MW, research reactors with more than 1,225 1,300 50 kW continuous thermal output SAARLAND DWR Obrigheim tor in accordance with the ‘polluter pays’ principle. The Temporary store under § 6 and accordingly § 7 AtG (Atomic Energy Act) Elm- SWR DWR BAVARIA Derlen 357 facilities currently available for the waste are those at Nuclear fuel disposal Philippsburg 926 1,458 DWR DWR SWR DWR the Gorleben site as well as the interim storage facilities Repository DWR SNR Karlsruhe Neckarwestheim Disposal 840 1,400 Isar Mitterteich and Nord (ZLN) near Greifswald. Radioactive (e.g. conditioning facility, temporary depot) 912 1,475 57 21 44.0 State collection depot SWR SWR SWR waste from the large research institutions will, as a rule, Gundremmingen Reprocessing plant be conditioned and temporarily stored at their points of 1,344 1,344 250 BADEN-WÜRTTEMBERG Munich/Garching/ In operation origin; medical, research and industrial waste is to be Neuherberg 20.0 4.0 1.0 deposited at the 11 state collecting depots where it will Planned/under construction Decommissioned/definitively be accepted either as raw or conditioned waste. Private shut down Nuclear power plant; figures: gross output waste management firms will also condition research, DWR = Pressurized water reactor in MWe SWR = Boiling water reactor Research reactor; figures: thermal output in MW, research HTR = High-temperature reactor In operation medical and industrial waste. Waste from the nuclear SNR = Fast-breeder reactor reactors with more than 50 kW continuous thermal output Overview of nuclear plants in Germany. Temporary store under § 6 and accordingly Planned/under construction § 7 AtG (Atomic Energy Act) Decommissioned/definitively Nuclear fuel disposal shut down Repository 36 DWR = Pressurized water reactor Disposal (e.g. conditioning facility, temporary depot) SWR = Boiling water reactor HTR = High-temperature reactor State collection depot SNR = Fast-breeder reactor

Reprocessing plant Processes such as smelting, compacting and Currently existent radioactive waste Konrad in depth cementing are employed to process solid raw Each year the Federal Office for Radiation Protection waste and intermediate products. carries out an assessment of existing and anticipated The term “radioactive waste with negligible Cementing, drying and vitrification are used to volumes of radioactive waste on behalf of the Federal heat generation” was introduced during the process any pre-treated liquid waste. Ministry for the Environment, Nature Conservation and course of planning the Konrad repository pro- Nuclear Safety. The information gathered from waste ject. Packing the waste products is carried out according producers and submitting sources in 2006 was evaluated to a system of safety and operational requirements In accordance with the planning standards for and the stocks of unconditioned and conditioned radioac- that has been agreed by all those involved. constructing the Konrad repository, low tive waste established according to the source of origin. radioactive waste and radioactive waste from In 2006, Germany had a total of 17 operational light The latest data from December 31, 2006 showed stocks decommissioning nuclear facilities were to be water reactors providing an overall output of 21,441 of approx. 17,000 cubic metres of radioactive solid waste disposed of. megawatts-electric (gross MWe). Of these, eleven were and raw waste. Conditioned radioactive waste is divided pressurised water reactors (PWR) and six boiling water into 91,000 cubic metres of waste with negligible heat Implementation initially involved ensuring that reactors (BWR). A total of 17 nuclear reactor blocks are generation and approximately 550 cubic metres of waste the underground temperature conditions would currently switched off or are already decommissioned, with heat generation. In the interim storage depots, be only marginally affected by the waste i.e. being dismantled or in safe embedment. there are also around 5,500 tonnes of heavy metal in packages. This ultimately led to the establish- the shape of spent fuel elements. Of the overall volume ment of the quantitative standard that the rise of waste with negligible heat generation, waste from in temperature caused by the degeneration of research facilities accounts for approximately 39,000 the radionuclides in the waste packages may not cubic metres, with the largest share – approximately exceed an average of three degrees Celsius at 25,700 cubic metres – originating from operating and the chamber face. decommissioning nuclear power plants. This value is roughly equivalent to the diffe- On the basis of the information provided by the waste rence in temperature for a depth difference of producers, the Federal Office for Radiation Protection 100 metres in a natural temperature field and was able to predict the future mount of conditioned radi- is small in comparison to temperature changes oactive waste with negligible heat generation that will be produced by 2040. A volume of about 280,000 cubic metres of accumulated waste packages is predicted, including the decommissioning waste from the power reactors.

Photo above: A waste container is filled with cement.

RADIOACTIVE WASTE 37 12. Repository conditions Waste: requirements and implementation.

The safety analysis generated a number of mandatory value of 10 mSv per hour. At a distance of 1 metre requirements that are to be fulfilled when delivering from the surface for cylindrical waste packages, and waste packages for disposal. These requirements have at 2 metres distance for containers, the local dose become the provisional conditions for disposal in Konrad. rate may not exceed 0.1 mSv per hour. Compliance with the conditions is monitored during pro- For certain alpha emitters, the limit is set at 5,000 duct control. Becquerel. At no point on the surface of the alpha emitter waste package may non-fixed surface conta- Basic requirements mination exceed an average of 0.5 Becquerel over an Regardless of the conditions for disposal, on delivering area of 100 square centimetres for certain beta waste packages for disposal the relevant laws, bye-laws, emitters, and for electron capture radioisotopes the regulations and other applicable rules – such as the limit is set at 5,000,000 Becquerel. For these, a value respective bye-laws governing the transport of dan- of 50 Becquerel per square centimetre may not be gerous substances – must be adhered to. exceeded on the surface of the waste packages. Radioactive waste for disposal may not be mixed with For all other nuclides, a value of 5 Becquerel per other substances for which the waste management act square centimetre may not be exceeded. (AbfG) applies, or which, according to Section 1. (3). 1 and The waste packages earmarked for disposal must be 3-8, do not fall under this law (see KONRAD IN DEPTH delivered unpressurised. on the right) The various forms of radioactive waste are to be pro- Picture above: Solid raw waste is compressed with high pressure and cessed to waste products in such a way that they Requirements for waste packages packed in waste containers. comply with the following requirements (basic require- The following are the most important requirements for waste packages: ments and special requirements) and can be allocated to They may not rot or ferment. one of the following waste product groups. The following The local dose rate (including that of the neutrons) on They may not contain either liquids or gases, with is a list of some of the basic requirements for waste the surface of each waste package on delivery to the the exception of a meaningfully attainable and products: Konrad repository is limited to an average value of 2 unavoidable residual content, which is found in millisieverts (mSv) per hour and to a local maximum They must be in a solid form. ampoules, bottles or other receptacles.

38 They may not contain free-flowing liquids or contaminated liquid must be taken into account when Konrad in depth release such liquids under normal storage and stating the level of activity. handling conditions. If radioactive waste contained in packaging with no Excerpt from the waste management act Section1 AbfG definition of values and scope They may not contain any spontaneously combusti- specific tightness is capable of releasing radon-220, the of application ble or explosive substances. waste product must be entirely enclosed by an inactive concrete floor measuring at least 40 millimetres in thick- (3) The provisions of this law do not apply to They may not contain fissile material capable of 1. those according to the dead animal disposal ness. The concrete encapsulation can be omitted if other absorbing thermal neutrons in excess of a mass act, the meat inspection act, the animal epide- activity limits are observed. concentration of up to 50 grammes per 0.1 cubic mic act, the plant protection act […] metres of waste product. The treatment (for example drying or concentrating) 3. waste produced during the search, extraction, of non-fixed radioactive waste in a waste receptacle is purification and reprocessing of minerals in For waste products that are produced using a fixing permitted if no changes take place which are capable of enterprises that are subject to the supervision agent (e.g. cement, concrete, bitumen or plastic), the compromising the barrier function of the receptacle. of the mining authorities with the exception of following additional basic requirements apply: Sections 5a, 23, 24. sub-section 1 in connection Waste products are to be assigned to one of six groups of with Section 5 and the respective penalty Reactions between the radioactive waste and the waste products. These differ in their safety requirements regulations that apply fixing agent and/or the packaging must be limited to with regard to the quality of a waste product. If a waste 4. gaseous substances not enclosed in receptacles a rate that complies with safety regulations. product fulfils the requirements of one of these groups, 5. substances, which have been fed or introdu- The fixing agent used must be wholly cured or have it can then exploit the permitted activity limits of that ced into bodies of water or waste water systems solidified entirely. group. 6. substances, with the exception of those referred to in Section 2, sub-section 2 and Waste product group 01 The sealing of radioactive waste or cavities between Sections 3, 5, 5a and 15, which have been duly (for example bitumen and plastic products): inner receptacles is to be carried out using appropri- recycled through a public utility collection The waste product must fulfil the basic requirements. ate fluid fixing agents, which are to be compacted 7. substances, with the exception of those refer- using technical methods (for example shaking) if Waste product group 02 red to in Section 2, sub-section 2 and Sections necessary. (for example solid substances): 3, 5, 5a and 15, which have been duly recycled Over and above the basic requirements, the waste through a commercial utility collection, provided The fixing agents used for sealing radioactive waste product must also guarantee that inflammable waste this is attested by the corporate body liable for or cavities between inner receptacles can also be substances with a melting point lower than 300 degrees disposal and does not interfere with prevailing mixed with contaminated liquid if the quality cha- Celsius are processed in such a way that they cannot be public interest racteristics of the respective waste product group discharged from the waste product if they are liquefied 8. the search for, recovery, transportation, are adhered to and compatibility with the item to be during thermal stress, or if they possess up to 1 percent storage, treatment and destruction of weapons. sealed is guaranteed. Radionuclides contained in the of the activity of the respective waste product.

DISPOSAL CONDITIONS 39 Waste product group 03 Requirements for waste receptacles Waste receptacle category I. (for example solid metallic substances): For transport, handling and stacking radioactive, waste Over and above the basic requirements, the waste recep- Over and above the basic requirements, the waste pro- products must be packed in receptacles which comply tacle is to be constructed in such a way that the oxygen duct must also guarantee that it consists entirely of with certain basic requirements and meet all the require- influx to the waste product is restricted to the extent ments of the conditions laid down in a design test. metal parts or of materials from components of a reactor that combustible waste products with a smelting point core with the exception of graphite. In particular, the waste receptacles must above 300 degrees Celsius pyrolise and do not burn with an open flame. In this respect, the integrity of the adhere to the external dimensions and gross volumes Waste product group 04 (for example pellets): waste receptacle must be maintained on impacts with a given in chapter 13, page 43. Over and above the basic requirements, the waste pro- velocity of 4 metres per second and subsequent thermal duct must also guarantee that the radioactive waste has be designed in such a way that, in a filled state, they exposure (fire at a temperature of 800 degrees Celsius been compressed into a stable form with at least 30 MPa can be stacked to a height of at least 6 metres with over one hour). forming power. no negative impact on either their leak tightness or integrity. Waste receptacle category II. Waste product group 05 Over and above the basic requirements, the waste (for example cemented/concreted waste): (insofar as they have specified leak tightness) receptacle must guarantee that Over and above the basic requirements, the waste pro- guarantee leak tightness either by virtue of their duct must also guarantee that the radioactive waste is construction or with a sufficiently tight inner it can withstand a fall from a height of 5 metres onto fixed in cement stone or concrete in such a way that packaging of the waste product. a rigid surface, the activity of the bonded or solidified radioactive waste (insofar as they are made of steel plate) be in a hostile fire with a temperature of 800 degrees (for example ashes, powders or concentrated aqueous constructed with an inner and outer protection Celsius lasting one hour, there is no prohibited solu-tions) is spread equally and completely throughout against corrosion and have a corresponding surface discharge . the cement stone or concrete. In addition, the activity in protection. cast radioactive waste (for example scrap metal) must be It is furthermore possible to use accident-proof packaging be delivered free of any mechanical and corrosive listed in waste receptacle categories I and II which must distributed in the waste product as evenly as technically damage, which could compromise their leak tightness fulfil further requirements. and reasonably feasible given the state of the waste. The and integrity during handling and stacking. compressive strength of the waste product must be at The waste receptacles can also be allocated to one of two least 10 Newton per square millimetre. Activity limits waste receptacle categories with regard to the safety The permissible activities for radionuclides and radio- requirements placed on the quality of the packaging. Waste product group 06 (for example concentrates): If a waste receptacle fulfils the requirements of one of nuclide groups (non-specified alpha, beta and gamma Over and above the basic requirements, the waste pro- these categories, it can then exploit the permitted acti- emitters) result from safety analyses for the operating duct must also guarantee that it comprises a solid body vity limits of that category provided that corresponding and post-operational phases of the Konrad repository. with a compressive strength of at least 10 Newton per packaging is used which is permissible within the given The requirements derived from such analyses exist inde- square millimetre and is non-combustible. waste product group. pendently of each another.

40 The most restrictive requirement governing the per-­ Radionuclide/ Waste receptacle category I Waste receptacle missible activities for radionuclides and radionuclide Radionuclide group Waste product groups category II, Waste groups in a waste package must be observed in each 01 02 03 04 05 06 product groups case. 01–06 I-129 3.0 • 109 3.0 • 109 3.0 • 109 3.0 • 109 3.0 • 109 3.0 • 109 7.5 • 1010 The table below gives examples of the activity limiting Cl-36 4.2 • 1010 4.2 • 1010 4.2 • 1010 4.2 • 1010 4.2 • 1010 4.2 • 1010 1.0 • 1012 values for reference nuclides and non-specified miscel- I-125 1.5 • 1011 1.5 • 1011 1.5 • 1011 1.5 • 1011 1.5 • 1011 1.5 • 1011 3.6 • 1012 laneous alpha, beta and gamma emitters which have Ac-227 3.6 • 108 1.8 • 1010 4.5 • 1010 1.1 • 1011 3.6 • 1011 3.6 • 1011 9.1 • 1012 resulted from the analysis of accidents. In addition to the Pb-210 1.0 • 109 3.5 • 1010 1.2 • 1011 3.0 • 1011 1.0 • 1012 1.0 • 1012 2.4 • 1013 9 11 11 12 12 12 14 activity limits derived from the safety analyses, the limi- Se-79 4.9 • 10 1.7 • 10 6.1 • 10 1.5 • 10 4.9 • 10 4.9 • 10 1.2 • 10 Sn-126 5.1 • 109 1.8 • 1011 6.4 • 1011 1.5 • 1012 5.1 • 1012 5.1 • 1012 1.3 • 1014 ting values for the maximum permitted activity per waste Cd-113m 5.1 • 109 1.8 • 1011 6.4 • 1011 1.5 • 1012 5.1 • 1012 5.1 • 1012 1.3 • 1014 package given in the transport regulations must also be Ra-228 5.1 • 109 1.9 • 1011 6.4 • 1011 1.5 • 1012 5.1 • 1012 5.1 • 1012 1.3 • 1014 adhered to. Sr-90 6.0 • 109 2.1 • 1011 7.5 • 1011 1.9 • 1012 6.0 • 1012 6.0 • 1012 1.5 • 1014 Ag-108m 6.7 • 109 2.4 • 1011 8.4 • 1011 2.1 • 1012 6.7 • 1012 6.7 • 1012 1.6 • 1014 The table on the right shows the maximum activities, as Am-242m 4.9 • 109 2.5 • 1011 6.1 • 1011 1.5 • 1012 4.9 • 1012 4.9 • 1012 1.2 • 1014 well as the maximum amount of overall activity for alpha, Nb-94 7.8 • 109 2.7 • 1011 1.0 • 1012 2.5 • 1012 7.8 • 1012 7.8 • 1012 1.9 • 1014 beta and gamma emitters that can be disposed of in the Na-22 1.6 • 1010 5.6 • 1011 2.0 • 1012 5.1 • 1014 1.6 • 1013 1.6 • 1013 4.0 • 1014

10 11 12 14 13 13 14 Konrad repository at the end of the operational phase. Rb-87 2.4 • 10 8.6 • 10 2.9 • 10 7.4 • 10 2.4 • 10 2.4 • 10 5.9 • 10 Eu-152 3.1 • 1010 1.1 • 1012 3.8 • 1012 1.0 • 1013 3.1 • 1013 3.1 • 1013 7.7 • 1014

10 12 12 13 13 13 14 Radionuclide/ Activity Co-60 3.5 • 10 1.2 • 10 4.3 • 10 1.1 • 10 3.5 • 10 3.5 • 10 8.6 • 10 Radionuclide group Bq Cs-137 3.6 • 1010 1.3 • 1012 4.5 • 1012 1.2 • 1013 3.6 • 1013 3.6 • 1013 9.1 • 1014 H-3 6.5 • 1017 Ra-226 4.4 • 108 1.5 • 1010 5.5 • 1010 1.4 • 1011 4.4 • 1011 4.4 • 1011 1.1 • 1013 C-14 4.0 • Pa-231 4.2 • 108 2.1 • 1010 5.2 • 1010 1.3 • 1011 4.2 • 1011 4.2 • 1011 1.0 • 1013 1014 I-129 7.0 • 1011 Th-232 1.0 • 109 3.6 • 1010 1.2 • 1011 3.0 • 1011 1.0 • 1012 1.0 • 1012 2.4 • 1013 Cm-248 9.1 • 108 4.5 • 1010 1.1 • 1011 2.8 • 1011 9.1 • 1011 9.1 • 1011 2.3 • 1013 12 Ra-226 4.0 • 10 Np-237 1.5 • 109 5.5 • 1010 1.9 • 1011 4.8 • 1011 1.5 • 1012 1.5 • 1012 3.8 • 1013 Th-232 5.0 • 1011 U-232 3.6 • 109 1.8 • 1011 4.5 • 1011 1.1 • 1012 3.6 • 1012 3.6 • 1012 9.1 • 1013 U-235 2.0 • 1011 Th-228 4.9 • 109 2.5 • 1011 6.1 • 1011 1.5 • 1012 4.9 • 1012 4.9 • 1012 1.2 • 1014 U-236 1.0 • 1012 Cm-245 5.1 • 109 2.5 • 1011 6.4 • 1011 1.5 • 1012 5.1 • 1012 5.1 • 1012 1.3 • 1014 U-238 1.9 • 1012 Cm-246 5.3 • 109 2.6 • 1011 6.5 • 1011 1.6 • 1012 5.3 • 1012 5.3 • 1012 1.3 • 1014 15 Pu-239 2.0 • 10 Am-243 5.3 • 109 2.6 • 1011 6.5 • 1011 1.6 • 1012 5.3 • 1012 5.3 • 1012 1.3 • 1014 Pu-241 2.0 • Am-241 5.3 • 109 2.6 • 1011 6.5 • 1011 1.6 • 1012 5.3 • 1012 5.3 • 1012 1.3 • 1014 1017 Pu-239 5.8 • 109 2.9 • 1011 7.3 • 1011 1.8 • 1012 5.8 • 1012 5.8 • 1012 1,5 • 1014 All alpha emitters 1.5 • 1017 All beta/gamma emitters 5.0 • 1018 Other alpha emitters 5.8 • 109 2.9 • 1011 7.3 • 1011 1.8 • 1012 5.8 • 1012 5.8 • 1012 1.5 • 1014

Maximum stored activities for relevant radionuclides or radionuclide Other beta and groups on sealing the repository at the end of the operational phase of Activity limits for reference nuclides and other non-specified alpha, beta and gamma emitters as a result of accidents. the Konrad repository. In Becquerel per waste package.

DISPOSAL CONDITIONS 41 13. Waste receptacles Packaging: types and requirements.

The prerequisite for ease of handling and therefore a smooth storing process is a system of standardised receptacles that meet the safety and operational needs of the Konrad repository. All told, eleven types of recep- tacle/packaging have been designated for use in the repository; they are described in more detail in the table on the right. There are three basic types:

1. Concrete canisters are reinforced, cylindrical recep- tacles made of standard or heavy-duty concrete. They are normally used by placing a radioactive waste-filled inner receptacle (for example a 200 or 400 litre barrel) into the cylindrical inner space of the concrete canister and pouring concrete into the remaining space, including at the top.

They are typically sealed using reinforced concrete, which is poured or screwed onto the body of the recep- tacle.

2. Cast-iron casks (cylindrical) are mainly used for packing non-fixed radioactive waste. They are made of cast material (for example GGG 40). Cast-iron casks vary in terms of their dimensions, the strength of the walls and the construction of the lid.

The lids of all types of cast-iron casks are also made of cast material and are screwed or welded onto the body Photo above: Cylindrical cast-iron casks can, for example, be used for packing non-fixed, activated or contaminated metal parts.

42 Number Designation Outer dimensions length/diameter (mm) Width (mm) Height (mm) Gross volume (m3) 01 Concrete canister type I 1,060 – 1,3701) 1.2 02 Concrete canister type II 1,060 – 1,5102) 1.3 03 Cast-iron cask type I 900 – 1,150 0.7 04 Cast-iron cask type II 1,060 – 1,5003) 1.3 05 Cast-iron cask type III 1,000 – 1,240 1.0 06 Container type I 1,600 1,700 1,4504) 3.9 07 Container type II 1,600 1,700 1,700 4.6 08 Container type III 3,000 1,700 1,700 8.7 09 Container type IV 3,000 1,700 1,4504) 7.4 10 Container type V 3,200 2,000 1,700 10.9 11 Container type VI 1,600 2,000 1,700 5.4

1) Height 1,510 mm + 90 mm bracket = 1,460 mm. 2) Height 1,370 mm + 90 mm bracket = 1,600 mm. 3) Height 1,370 mm on type KfK, volume: 7.2 m3. 4) Stacking height 1,400 mm on type KfK, volume: 7.14m3.

Photo above: Cylindrical concrete canisters are used, for example, The different types of standardised waste receptacles for the Konrad repository. for packing decontaminated cemented liquid.

of the container.

3. Containers are large-volume rectangular receptacles made of steel plate, reinforced concrete or cast mate- rial. Depending on the waste product, different types of container are chosen, all of which differ from one ano- ther in terms of their construction, dimensions and wall thickness.

The container lids are, for example, screwed onto the body of the receptacle or clamped with tie rods. The largest box can accommodate up to 28 200-litre barrels.

Photo left: Container type I with stacker.

WASTE RECEPTACLES 43 14. Product control Monitoring: an on-going process.

The original producers and conditioners are responsible Random inspections consistency of the waste package and the test results for ensuring that disposal requirements are met. The On behalf of the Federal Office for Radiation Protection, of previous random inspections, the sample size is given Federal Office for Radiation Protection, as repository experts from the Technical Inspection Agency (TÜV Nord a value of between 0 (for example for data ascertained operator, is responsible for checking the information Ensys Hannover GmbH & Co) and the Product Control during official controls) and 12 percent. given on the waste packages Office in J¸lich carry out random inspections of, above all, so-called old waste, which has been conditioned largely Process qualification 1. by carrying out random inspections on completed without being controlled by independent experts. They The pre-treatment and conditioning of radioactive waste waste packages, or open existing barrels, for example, or take gas or inner intended for disposal is usually carried out in qualified pressure measurements. To begin with, batch is divided processes laid down by the Federal Office for Radiation 2. by qualifying conditioning processes and stipulating into inspection lots comprising similar waste packages. Protection. Fundamentally, a differentiation is made bet- the accompanying control measures. Depending on the radiological relevance, the available ween campaign-independent and campaign-dependent documents, the possibility of post qualification, the process qualification.

Campaign-independent process qualification A campaign-independent process qualification is expe- dient for uniform waste flows. The operating regulations for conditioning facilities of relevance to adherence of the repository requirements are set out in a manual. Pro- cess qualification is performed by the Federal Office for Radiation Protection which also determines the accom- panying inspections. Compliance with the qualified opera- ting requirements must be verified on the basis of accom- panying controls such as the analysis of raw waste and recording of the process parameters (such as tempera- ture and input amount). Before the waste packages are transported to the Konrad repository, confirmation must

Photos above: Product control stations. be provided that the documents are complete and all

44 the necessary procedural steps have been duly carried relevant documents and data sheets, the Federal Office The concept behind this is to give priority to process out. for Radiation Protection then issues a statement qualification, since controls performed throughout the process are capable of achieving greater accuracy than confirming that the stipulations laid down in the Campaign-dependent process qualification process schedule plan have been duly executed/ random tests carried out on the waste products, and In this case, an assessment of the procedures relating completed, and dose exposure for personnel is minimised. to raw waste is conducted on the basis of the existing verifying that the disposal requirements or – depen- documents. The Federal Office for Radiation Protection ding on the individual case – certain elements of these Photo below: Radioactive waste is pre-treated in accordance with the is responsible for approving the process and stipulates requirements have been met. stipulations laid down by the Federal Office for Radiation Protection. which accompanying inspections must apply. Compliance with disposal requirements is assessed on the basis of the findings of the individual work steps and testing sequences.

In practice, a combination of random tests and process qualification – the process plan procedure – has proved effective. This involves the Federal Office for Radiation Protection qualifying the conditioning processes for radi- oactive waste in a process assessment. The conditioner obtains confirmation of the disposal-relevant waste cha- racteristics as well as the waste packaging documents from the Federal Office for Radiation Protection. ­- Stan dardised process schedule plans have been developed for carrying out the required work and/or tests.

In approving the process schedule plan, the Federal Office for Radiation Protection assures that, based on the knowledge available at the time, all measures con- form to disposal requirements and all disposal-relevant data has been documented.

Following submission of the test report on waste or intermediate products, which has been compiled by the commissioned expert, among others, on the basis of the

PRODUCT CONTROL 45 15. Storage The process: delivery and storage.

In the course of planning the conversion of the former site of the Konrad iron ore mine into a repository for radioactive waste, it became apparent that, from a safety

and organisation point of view, allocating conventional 3 mining operations to one shaft and the disposal of waste packages to another would bring significant benefits. It is 13 2 for this reason that Konrad Shaft 1 continues to be used for conveying broken ore and materials as well as for man-riding. At Konrad Shaft 2, completely new surface 1 installations are being constructed to enable waste 12

packages with an overall weight of up to 20 tonnes to be 10 conveyed underground. 7 9 With this division of tasks, the conveyance below ground 6 11 14 of waste packages and broken ore can be accomplished 5 8 via two separate drifts. Disposing of radioactive waste via the air exhaust shaft in Konrad 2 has the advantage 4 that, in the event of a possible accident, the contamina- ted air cannot be drawn into the mine.

The control area underground is therefore only that area of the mine where the actual disposal operations are being performed.

Konrad Shaft 2 comprises a headframe with cage hoisting, large cage and counterweight. It is designed for The planned above-ground facilities on the grounds of the repository: payloads of 25 tonnes and a maximum hauling speed of 12 1 Reloading hall 2 Konrad 2 winding tower and shaft building 3 Security building 4 Engine shed 5 Warehouse and workshop metres per second. The conveyor is an eight-rope, direct- 6 Friction winch 7 Substitute conveyor, fork lift truck and garage 8 Diesel pump 9 Staging area 10 Helicopter landing site drive electric Koepe hoist. Waste packages designated for 11 Truck parking area 12 Buffer hall 13 Mine water transfer station 14 Shielding wall

46 disposal are delivered as freight units on goods wagons In the reloading hall A conveyor track system transports the flatbed wagons or lorries that comprise a container or pool/transporta- In separate package-reloading areas located in the reloa- individually to one of the radiation measuring stations. ble pallets with a maximum of two cylindrical waste ding hall, the freight units are transferred by overhead Once cleared, they are then taken via crossway 2 and packages. crane from the lorries or goods wagons to the waiting through the buffer tunnel to the shaft barrier in front flatbed wagons. of the turntable in the shaft house. In the event of any Means of transport The waste producers are responsible for delivering the

waste packages as well as for choosing the means of Planned storage procedure from acceptance transport. As most of the 50 or so waste producers of the waste package to disposal. Flatbed wagon have a railway siding, the vast majority of consignments are expected to be sent by rail. In order to estimate the volume of traffic and handling procedures, two possible Winding tower options were examined during the planning stages. Buffer hall

Buffer tunnel Straddle carrier Delivery Deutsche Bahn AG (German federal railways) delivers the Reloading hall

freight units in closed goods wagons to Beddingen trans- Delivery By road fer station, from where Verkehrsbetriebe Peine-Salzgitter Measuring station GmbH takes on the task of transporting the freight to the Transport wagon perimeter of the mine. From there, company-owned shun- By rail Shaft ting engines transport the goods wagons through gate 2 via the railway system to the buffer. Up to three goods Side stacker Overhead crane wagons at a time are then transported via the drying Spacer plant to the reloading hall. Lorries coming from the north reach Konrad Shaft 2 via the approach road. After being Loading area checked, they then drive either directly into the reloa- ding hall via the lorry drying plant or to the mine’s lorry Stacker parking area. The lorries or goods wagons are freed of Unloading chamber Transport route any water, snow or ice in the drying plant before being manually opened in the reloading hall. Direction of transport of packages Disposal chamber

Stored packages

STORAGE 47 Unloading the containers. Stacker. Straddle carrier.

disruptions in the shaft area, the loaded flatbed wagon In the disposal chamber approach areas to the disposal chambers, between the is transported via the conveyor track system through The transport wagon takes the freight units to the dispo- transport route and the respective unloading chambers. crossway 1 to the reloading area of the buffer hall. A side sal chambers. At the entrance of the disposal chambers Diagrammatical representation of underground mining: stacker removes the freight unit from the flatbed wagon are unloading chambers within which a stacker removes see diagram on right. and sets it down in the buffer hall. To remove it from the pool/transport pallets or container from the trans- the buffer hall, the side stacker lifts the freight unit and The cross-section of these drifts measures approxima- port wagon. The disposal chambers are filled with waste places it on an empty flatbed wagon, which is then trans- tely 25 square metres; the chamber seals are 12 metres packages using the technique of working backwards ported via the conveyor track system to the shaft barrier long at least. It is anticipated that the radioactive waste whereby cylindrical packages are laid on their sides. in front of the turntable. will only be disposed of in one layer per pit. Whether a The remaining cavities are filled section for section. From here, a cantilever crane hoists the flatbed wagon two-layer system will be introduced or not will be decided Broken ore extracted during the extraction phase and onto the turntable. Once the cage has been filled and following a test phase, whereby the actual volume of converted to high-consistency fill material is used as cleared, the flatbed wagon is taken underground. On waste at the time will be considered. backfill. Filled disposal chambers are then sealed. The arrival at the loading area, a cantilever crane is used to An annual average of 17 freight units per layer could be aim of the seals is to close off the disposal chambers remove it from the cage and put it into the loading area transported underground. Based on an average of 230 filled and backfilled with radioactive waste from the in readiness for unloading. A rail-mounted straddle car- workdays per annum, this would mean around 4,000 rier travels over the flatbed wagon, lifts the freight unit, open mine whilst the repository is in operation so as to freight units could be stored per year using the one-layer drives over the transport wagon and places the freight minimise any radiation exposure for personnel operating option. unit onto it. the mine. The chamber seals will be constructed in the

48 Konrad Shaft 1 Konrad Shaft 2

Old working chambers which are not to be used for disposal. Storage spaces

Model of the deep geological substratum in the area of the Konrad repository.

STORAGE 49 16. Safety analyses Operations: responsibility towards people and the environment.

Location-specific safety considerations were given the Konrad repository could operate safely. The plan waste packages is limited to 0.1 mSv per hour, and to extensive attention in the course of the plan approval approval resolution – along with its collateral clauses – is 2 mSv per hour on average on the surface of the package. procedure for the Konrad repository. With the aid of binding on the construction and operation of the Konrad safety analyses, potential sources of danger were iden- repository. The competent nuclear and mining inspection Personnel radiation exposure tified and model calculations carried out in order to authorities will monitor compliance with the stipulations. Comprehensive boundary conditions, including full determine the potential effects on operating personnel usage of the permitted surface dose rates for waste as well as on the general public and the environment. In Protecting the population and personnel from packages, were taken as the basis for estimating per- the model calculations, not only were the planned opera- waste-induced radiation sonnel radiation exposure. The safety analysis revealed ting requirements considered and assessed, but also the Prior to commencing operations at the Konrad reposi- that the annual effective dose for operating personnel possible impact of external influences. Long-term safety tory, guarantees must be given that the operating per- exposed to radiation was less than 5 mSv. analyses also examined potential developments at the sonnel and the population will be sufficiently protected Radiation protection measures such as shielding work Konrad repository following sealing and the potential against radiation. Compliance with the limiting values places and vehicles were also taken into account in the effects of such developments. laid down in the Radiation Protection Ordinance is man- prognosis. The parameter values and assumptions for the location- datory. The Radiation Protection Ordinance also includes specific safety analyses were consciously chosen in order guidelines for the operational organisation of radiation to ensure that these effects could not be underestima- protection, such as the creation of radiation protection Radionuclide/ Activity levels zones where special admittance regulations apply, as ted. The effects were assessed on the basis of the limita- tions that had to be complied with. The safety analyses well as the introduction of measures to determine indi- Radionuclide group Bq/a H-3 1.5 • 1013 were also used to help establish what requirements nee- vidual dose equivalents, local dose rates and concentra- C-14 3.7 • 1011 ded to be met by the technical systems and components, tions of activity in the mine air. I-129/I-131 7.4 • 106 Rn-222 7.4 • 1011 Exhaust air operating procedures and the waste packages subject to When operating the Konrad repository as prescribed in Aerosols disposal in order to ensure the safe running of operations the Ordinance, personnel could especially be exposed to (Half life > 10 d): Alpha emitter 3.7 • 106 and to minimise impact. radiation fields (direct and stray radiation) emanating Beta/gamma emitter 7.4 • 107 The safety analyses were carried out by external experts from the waste packages. At a distance of 2 metres from H-3 7.4 • 1012 Waste water on behalf of the Lower Saxony Ministry for the Envi- the surface of the container or 1 metre from the surface Limiting values for activity release with exhaust air and waste water at ronment. The plan approval resolution confirmed that of cylindrical waste packages, the local dose rate for the Konrad repository.

50 In mathematical terms, individual work places demons- Exposure route Exposure to radiation and threshold values Konrad in depth 16. Safety analyses trated relatively high levels of radiation exposure. For according to the Radiation Protection Ordinance (StrlSchV) in millisieverts per year this reason, the plan approval authorities introduced Excerpt from the Radiation Protection collateral clauses with the aim of reducing personnel Infant Adult Threshold A age < 1 year old age > 17 years old value Ordinance (StrlSchV) Operations: responsibility towards people and the environment. radiation exposure levels to a minimum. Exhaust air (ß 47) 0.05 0.028 0.3 Section 5 StrlSchV Dose limitations Small amounts of volatile radionuclides are released from Waste water (ß 47) 0.139 0.061 0.3 Whoever plans or performs an activity defined the waste packages into the mine air. The air in the mine Direct radiation 0.61) 0.6 2) (ß 46) under Section 2, sub-section 1 (1) a to d, or has also contains the radioactive gas radon from the host Total from 0.79 0.69 1 such an activity carried out is required to ensure rock, which is therefore a natural source of radiation. discharge and direct that the dose limits stipulated in Sections 46, radiation (ß 46) The safety analysis also allowed for the eventuality that 1) For exposure to radiation through direct radiation, the value for adults is also used for infants. 2) The threshold of 1 millisievert per year applies for direct radiation, less the exposure from discharge. 47, 55 56 and 58 are not exceeded. The limi- inhaling these radionuclides could result in operating Comparison of calculated maximum exposure to radiation through direct ting values for the effective dose in a calendar personnel being exposed to radiation. radiation and the discharge of radioactive material in exhaust air and year are, in accordance with Section 46, sub- waste water from the Konrad repository, with the threshold values section 1 governing the protection of individual contained in the Radiation Protection Ordinance. The effective dose is Radiation exposure to the general population shown for the most exposed person (infant) and adults. members of the population, 1 millisievert, and, Ionising radiation emitted by waste packages, and radio- in accordance with Section 55, subsection 1 (1) active substances discharged into the surrounding area governing the protection of individuals exposed fence for a whole year, the maximum effective dose with exhaust air and waste water (liquid waste from to radiation in the course of their occupation, 20 during that year would be 0.6 mSv. Here, too, the calcu- operations and mine water) can lead to the general popu- millisieverts. lations made allowances for all of the safety measures lation being exposed to radiation. that had been assumed. Even at the most unfavourable The plan approval resolution stipulated permitted acti- location, the limiting value stipulated by the Radiation vity levels with exhaust air and waste water. Under these Protection Ordinance of 1 mSv per annum for individuals radiation can have on human beings. However, the effect stipulations, the annual emission of natural radioac- will be observed without difficulty. of ionising radiation on people depends, to a very large tive substances with mine water was limited to 3.35 x extent, on the intensity and duration of the radiation. 106 Becquerel for thorium-232 and each nuclide of the Effects of ionising radiation High radiation – such as was released in Chernobyl, Hiro- thorium decay chain as well as 2.25 x 106 Becquerel for In order to assess the health risks of ionising radiation, shima and Nagasaki – is linked to a high risk of cancer; uranium-238 and each nuclide of the uranium-radium scientific examinations were carried out on sections of a lower level to a correspondingly lower risk. Scientists decay chain. For no population age group does the maxi- the population that had been exposed to radiation – for now assume that there is no threshold value below which mum level of radiation through the discharge of radio- example Hiroshima and Nagasaki survivors, victims of no additional risk of cancer exists. active substances in waste water and exhaust air during the reactor catastrophe at Chernobyl, or groups of peo- repository operations exceed an annual effective dose ple employed in nuclear plants. The analyses presented of 0.19 mSv. If someone were to stand at the repository a very clear picture of the devastating effects ionising

SAFETY ANALYSES 51 Dose and risks via a pipeline to the receiver. Otherwise the water will As, by implication, all radiation exposure causes a health not be fed into the pipeline, but disposed of externally or risk, the limiting values of the Radiation Protection solidified for disposal in the Konrad repository. Ordinance are designed to ensure that the risk to the The Radiation Protection Ordinance also makes it man- population is as small as possible. Dose limits are often datory to determine the local dose rate and the acti- erroneously regarded as being the dividing line between vity from samples taken from the surrounding area in ‘dangerous’ and ‘harmless’ radiation. If this value is accordance with a pre-determined plan through which potential entries of radioactive substances into the envi- continually exceeded, each individual will be exposed to ronment would be noticed. The findings of this environ- a level of radiological risk that has been deemed by the mental monitoring will be published. legislator as unacceptable. A linear dose-response relati- onship is postulated, meaning that dose values below the The avowed aim of the Federal Office for Radiation Pro- tection is to keep unavoidable discharges and related limiting values can also lead to illness (known as the LNT radiation exposure as low as possible, including below hypothesis). It is on this relationship that the minimisa- the statutory limiting values and the permitted discharge tion directive of the Radiation Protection Ordinance is values. founded. This directive requires the operators of nuclear plants to keep all (including those below the limiting Accidents values) levels of radiation or radioactive contamination In addition to conducting a safety analysis of operations for people and the environment as low as possible. In the as prescribed under the Ordinance, accident analyses process, state of the art science and technology must were also carried out. be observed and all individual circumstances taken into On the basis of a technical analysis of the envisaged consideration. operational procedures and the potential impact resul- ting from technical or human error or rock mechanics, those events were identified which could result in the Emissions from Konrad release of radioactive substances into the surrounding When Konrad is put into operation, all emissions will area. be quantified and monitored to ensure that the permit- ted emission values are not exceeded. Representative In order to determine the accidents caused by the faci- samples will be taken from the waste water. Following lities themselves, it is expedient to divide the repository detailed laboratory testing aimed at providing informa- into the three sections: surface installations, conveyance Crash test: The waste package is enclosed in a container and dropped tion as to whether the recorded values are below the equipment and underground installations. Mechanical or onto a rigid surface. Special care is taken to collect all the released dust and aerosol-like matter on filters and to quantify it. permitted discharge values, the waste water will be fed thermal impact on the waste packages can chiefly occur

52 on waste packages were divided into groups with com- Konrad in depth parable radiation exposures and then investigated to

establish which events could result in the maximal levels Excerpt from the Radiation Protection of activity discharge. A total of 79 events related to the Ordinance (StrlSchV) handling of waste packages were assessed and catego­ Section 46 StrlSchV Limiting radiation rised into two groups: events for which the radiological exposure for the population impacts are limited by the construction of the installation or of the waste package (category 1), and events that (1) For individual members of the public, the could be avoided by carrying out construction measures effective dose for radiation exposure during to the installations or to the waste packages (category 2). activities defined under Section 2, sub-section 1 (1) is 1 mSv p.a. Events in category 1, for which maximum radiological impacts were determined, served to establish the requi- (2) Notwithstanding sub-section 1, the limit value for the organ dose for an eye lens is 15 mSv per rements for waste packages, for example. calendar year and the limit value for the organ The following three accidents were identified as being dose for the skin 50 mSv per calendar year. Fire test: Inactive test receptacles are used to test the effects of fire on radiologically comprehensive: waste packages. Substances released with the smoke from the fire are (3) With respect to plants and facilities, the limit the falling or dropping of waste packages during collected on filters and quantified to establish how much radioactivity value off premises for the effective dose, as can be released from a waste package in the event of fire. reloading in the surface installations from a height of defined under sub-section 1, applies for the sum less than 3 metres; total of radiation exposure from direct radiation the falling or dropping of waste packages during and radiation exposure through emissions. The through the following incidences: storage in the disposal chamber from a height of less maximum lengths of stay in areas subject to radi- waste packages falling or being dropped; than 5 metres; and ation exposure through direct radiation depend fire occurring underground on a loaded transport heavy loads falling onto waste packages;  on the spatial circumstances prevailing at the vehicle (temperature = 800 degrees Celsius, duration: plant or facility or on the site; continuous stay collisions involving means of transport, with and 1 hour) is to be assumed possible if no substantiated without combustion; Experts appointed by the planning approval authori- details on the length of the stay are provided. vehicle fire; ties investigated the possible radiological impacts of a fire in the installation; postulated aeroplane crash on the surface installations explosion in the installation. of Konrad Shaft 2. An additional analysis looked into the possible radiological impacts of a fully fuelled, four Postulated accidents with mechanical or thermal impact engine civil airliner crashing into the buffer hall.

SAFETY ANALYSES 53 The planning approval authority is satisfied that the be protected from the harmful effects of the radionu- effects of accidents not prevented with sufficient cer- clides and non-radioactive contaminants contained in the tainty by the installation structures, will be so limited by waste. the structures that they are not expected to exceed the By way of furnishing proof that this objective will be accident planning values (in particular 50 mSv effective attained, geoscientific methods were used to forecast dose) given in the Radiation Protection Ordinance. The the long-term development of the Konrad repository. The Federal Office for Radiation Protection has also adequa- possible dispersion of radionuclides from the repository tely observed the minimisation directive contained in into the groundwater close to the surface was investiga- the Radiation Protection Ordinance by self-imposing an ted in model calculations. In order to ensure that no radi- accident planning value of 20 mSv for the effective dose. onuclides would at any point in time enter the groundwa- ter in concentrations that could endanger people and the Heat generation environment, the maximum anticipated effects of using The Konrad repository is only earmarked to dispose of the groundwater – e.g. in farming for watering crops and radioactive waste with negligible heat generation. The cattle, or in use as drinking water – were determined. In temperature rise caused by decay heat in the radionu- doing so, the boundary conditions and input parameters clides contained in the waste must not exceed three of the model calculations were chosen in such a way that degrees at the chamber face. This value is roughly equi- they always covered a more unfavourable scenario – for valent to the difference in temperature for a depth diffe- example, the relatively rapid dispersion of radionuclides rence of 100 metres in a natural temperature field and is – and produced results that exaggerated the effects on small in comparison to temperature changes caused by people and the environment. ventilation. On the basis of currently available operati- Photo above: Preparing samples from the surrounding area to onal experience, no significant impacts on the safety of Parallel to this long-term radiological safety analysis, a determine activity. the repository are expected as a result of temperature test was conducted to examine whether non-radioactive The levels of radiation exposure calculated by the changes occurring in connection with the storage of contaminants (such as lead or cadmium) in the waste experts show that no catastrophic radiological impacts radioactive waste. In the safety analysis on the thermal could result in dangerous pollution of the groundwater, or are anti-cipated for the general population from either of effects on the host rock, the heat capacity of radionu- otherwise unfavourably modify the quality and properties the hypothetical scenarios that were considered. clides was distributed in a disposal chamber in a model of the water. and the activity limits for waste packages. The planning approval authorities have determined that, Observations of the model revealed that entries into the in terms of its safety, the Konrad repository has a well- groundwater close to the surface could only occur after balanced design and that all necessary precautions Long term safety around 300,000 years. The first of these would involve required to prevent damage comply with state-of-the-art The aim of the repository is to safely and permanently radionuclides such as iodine-129, which are only margi- science and technology. seal radioactive waste in deep-lying geological forma­ nally retained by the rocks surrounding the repository. tions. Through this, people and the environment are to The transportation of long-life radionuclides with greater

54 retention takes much longer. The model calculations (ICRP) recommends defining a guideline value for the Konrad in depth revealed that radium-226, for example, will not return in phase following sealing of the repository to limit the indi- relevant concentrations for several million years. vidual dose or the individual risk to below 0.3 mSv p.a. Excerpt from the Radiation Protection for the effective dose, or below 10–5 p.a. for the individual Ordinance (StrlSchV) Potential radiological impacts risk. Internationally, the additional risk of the general To determine the level of radiation exposure in the bios- population suffering severe radiation-induced diseases Section 6 StrlSchV Avoidance of unnecessary phere, the maximum concentrations of radionuclides in terms of life-long radiation exposure following the radiation exposure and dose reduction discharge of radiation from the repository is deemed to found in groundwater close to the surface were taken (1) Whoever plans or performs an activity be low if the calculated value of the additional risk is at as a basis. Radiation exposure was calculated in keeping defined under Section 2, sub-section 1 (1) is with the guidelines of the Radiation Protection Ordi- least smaller than 10–4, ideally smaller than 10–6. Calcula- required to avoid all kinds of radiation exposure nance. tions for the Konrad repository have shown that, in the or contamination for people and the environ- case of radiation being released, the maximum effective To assess the potential radiological impacts of the Kon- ment. doses that can be reached are 0.26 mSv p.a. for an infant rad repository in the phase following sealing, the planning and 0.06 mSv p.a. for an adult. These calculated radiation (2) Whoever plans or performs an activity approval authority took the value 0.3 mSv p. a./individual exposures are equivalent to additional risks in the region defined under Section 2, sub-section 1 (1) is dose as the decision criterion. This decision criterion is of about 10–4 to 10–5 in terms of life-long exposure. required to keep all radiation exposure or con- based on the stipulations published in “The Safety Cri- tamination for people or the environment as low teria for the Disposal of Radioactive Waste in a Mine” The concentrations of the other non-radioactive contami- as possible – including below the limiting values published and circulated by the then (1983) responsi- nants were estimated in keeping with the boundary con- – and, in doing so, to give due consideration to ble Ministry for the Interior. The Radiation Protection ditions and guidelines of the long-term radiological safety all individual circumstances and state-of-the-art Ordinance itself does not specify a limiting value for the analysis. In the final outcome, no unfavourable changes dose following sealing of the repository. Since the safety to the groundwater are to be feared from non-radioactive criteria from 1983 no longer represent the current level substances. Even if these substances were to enter the of science and are currently under review, the planning groundwater, their concentrations are below the rigorous approval authorities have acknowledged internationally limits prescribed under the drinking water ordinance and applicable and discussed decision criteria and included other relevant laws and regulations relating to water and these in its assessment. waterways. Overall, the possibility of radionuclides and other con- International risk assessment taminants released from the repository affecting the Internationally, dose values, and increasingly also risk groundwater close to the surface is so slight that neither values, are being applied as decision criteria when appro- people nor the environment need fear any detrimental ving and licensing repositories. By way of example, the consequences. International Commission on Radiological Protection

SAFETY ANALYSES 55 17. Interview on radiation protection: “The public has no reason for concern”.

The interviewees from the Federal Office for Radia- Dr Kunze, the first question goes to you: does the tested this here in the procedure. In the plan appro- tion Protection are Dr Christiane Wittwer, head of the public have reason to be concerned once radioactive val decision, the authorities confirmed that that these specialist area covering protection from radiation during waste begins to be stored in the Konrad repository, threshold values will be respected and values should disposal, and Dr Volker Kunze, assistant head of the from 2013? even be significantly lower during operation. The safety Konrad project group and responsible there for safety Dr Kunze: In my opinion, the public has no need for considerations made previously are based on so-called technology and radiation protection. concern. As someone whose professional responsibilities ‘covering assumptions’. The assumptions have been involve dealing with radioactivity and protection from selected so as to take into account all operating con- radiation, I am in a good position to assess that. It is our ditions imaginable for the repository, and ensure that Dr Volker Kunze duty to understand the public’s concerns and address all results produced by way of the analysis are almost them by working to proactively put out information that maximum values. By implication, it follows that the actual clearly explains the facts. For example, we are pleased to effects during operation will be less. be able to offer citizens the opportunity to find out about radiation levels online. The Federal Office for Radiation Dr Wittwer, how have the threshold values been arri- Protection has already installed the same measurement ved at and how will new scientific learnings be taken sensors on the plant grounds, for testing purposes, as are into account in establishing permissible exposure?

operated by it throughout Germany to ensure the fast Dr Wittwer: Let me start by saying that the threshold calculation of artificial radioactivity in the environment. values have been established by the authorities and Two additional sensors will be added at Konrad 2 at a absolutely have to be respected – they cannot be later date. exceeded. The threshold values should not, however, be viewed as a separating line between “harmless” and What threshold values will apply to the Konrad “dangerous” exposure”. The values are based on the repository in respect of ‘ionising radiation’? recommendations of scientists who study the effects of Dr Kunze: The most important threshold value under radiation on people. The recommendations are reviewed normal operation is that of 1 millisievert per year for any on an ongoing basis and when new learnings are presen- member of the population. ted, indicating that threshold values need to be tighte- That is a generally applicable protection target that ned, this is taken into account by the authorities in the also applies to all other nuclear plants, and we have also Radiation Protection Ordinance.

56 In addition to the research conducted on its own account Dr Wittwer, how can people be sure that threshold by the radiation protection experts of the Federal Office values will not be exceeded at the Konrad repository? for Radiation Protection, research projects are also Dr Wittwer: As with all nuclear facilities, with the com- commissioned and technically supported by it. In exhau- missioning of the Konrad repository, all emissions will stive studies, effects caused by radiation are investiga- be metrologically recorded and checked against the per- ted at much lower levels than that occurring from natural missible amounts of output established in the plan sources. approval decision. There will also be a comprehensive programme of measurement for the monitoring of envi- Natural sources of radiation, too, cannot be considered ronmental media, which will ensure that any possible harmless. Consider, for example, mine workers exposed incorporation of radioactive materials into the envi- to high concentrations of radon, causing them to become ronment is detected. Experience shows us that actual ill with lung cancer. Now that research has clearly establis- emissions during operation will be far lower than those hed this link, the Federal Office for Radiation Protection forecast. In addition, we have a duty to keep any expo- also recommends reducing the concentration of radon sure to radiation or contamination of people or the envi- that people are exposed to in living and working spaces. ronment to as low levels as possible, irrespective of the threshold values. How important is the recent research study into cancer in children conducted by the BfS in terms of Dr Kunze, what emissions will be released from Kon- protection from radiation? rad? The report on cancer in children living in the proximity of Dr Kunze: A differentiation needs to be made here. There nuclear power plants (“KIKK Studie”) shows that the risk will be direct radiation: that is to say, radiation coming Dr Christiane Wittwer for children aged under five years old of becoming ill with from the waste packages. One can imagine that as a lamp that, so to speak, lights up people who find themselves in leukaemia increases, the closer the place in which they the vicinity. live lies to a location of a nuclear power plant. Given the Dr Kunze – so that means that we’re not talking clear significance of distance, there are suggestions of a After this, there is the possibility that radioactive about ‘zero emissions’ here? possible connection with radiation, but no proof. In such material might be emitted into the environment. This Dr Kunze: As with the currently practised above-ground cases, more has to be found out as to what might cause could be caused, on the one hand, by waste water from the mine and the above-ground checking area, which is temporary storage, there will also be no ‘zero emissions’ the leukaemia in children. to be initially gathered and then subjected to a control situation here. However, once the waste has been stored Just how much is ‘1 millisievert’? measurement, and can then be released into the Aue and the corresponding storage areas sealed, practically Dr Wittwer: 1 millisievert amounts to around half the dose stream. On the other hand, this might occur via the no further emissions will be produced. The whole point of radiation that each of us will be exposed to through exhaust air from the underground storage areas and the of disposal is to create a more efficient, maintenance- natural sources over the course of a year. above-ground reloading hall. free situation than when waste is stored above ground.

interview 57 In respect of emissions, we have considered safety from A lot of research has been conducted on the subject myself? This is not the case. The threshold values ensure the point of view of what can be expected with such a – has it all been taken into account in respect of the that no usage limits will be applicable to foods or similar repository and the storage operation as planned here, repository? products. and derived values. These annual emission values of Dr Kunze: If you are asking whether the effect of ionising Is the exposure that will be produced during ope- radioactive materials are confirmed in the plan approval radiation on people has been taken into account, then ration of the repository comparable with that of a decision. naturally that is the case. All potential routes of expo- nuclear power plant? We are nonetheless extremely confident that we will not sure need to be considered. We have addressed direct Dr Kunze: It can be compared to the extent that the same reach these maximum values under operation. ex­-posure, and also the issues connected with the emis- legal requirements are in place, the same protection aims, sion of radioactive material through the air and water. and the same threshold values that must be respected. These radioactive materials could naturally be found in However: in respect of radionuclides, which play a role foodstuffs in the surroundings. They might penetrate here, the considerations here are rather different than the entire material cycle. These other potential sources with a nuclear power plant. When it comes to the pro- of exposure, that people might ingest food exposed to tection of the public, on the other hand, there is no radiation – even at very low levels, given that animals difference, given that the calculated dose is ultimately will be drinking water exposed to tiny amounts of radia- what determines the assessment of the level of radiation tion – all these possibilities of how radionuclides could in protection. theory penetrate the human body, are included. This is considered in an overall picture within which, even taking these named routes of exposure as a basis, the threshold How safe are the transport routes and the transport? value of 0.3 millisieverts per year for the disposal of Dr Kunze: In terms of safety in shipping, the same pro- waste water and exhaust air is certain to be kept below. tection principles apply as for the operation of the repo- sitory. As for potential effects, the first thing one has to consider is potential direct radiation. When it comes To ask the question again, leaving no room for doubt: to protecting the public, however, should the shipments that means that all calculations show that the go as planned, people will only be exposed to radiation highest values will not be attained here in the coming from the waste packages for very short period of Konrad mine? time, if at all. Dr Kunze: That is truly a key point, and it will also not be the case that restrictions are placed on usage. Questions The way we see it, what naturally concerns the public such as these are repeatedly asked by the public: do I much more is the question of transport safety. We there- now have to give up eating vegetables that I’ve grown fore commissioned a transport study and have also had

58 it updated. A similar study had already been conducted reason that protection against radiation is so important. in 1991. It is currently being adapted to the changed para- As a precaution, all radiation protection concepts are meters. We will then present the information obtained to based on the assumption that a linear correlation exists the public. between even low doses and the probability of beco- ming ill, and that no threshold exists beneath which that What risk would there be in the event of a transport probability is zero. Following on from these assumptions, accident? even with slight exposure, there is a potential that it will Dr Wittwer: Even if a transport accident were to occur, no cause illness, even if the probability of that happening is unacceptable effects would result for the public. very low. The threshold values of Germany’s Radiation Protection Ordinance have been set in such a way that How can you guarantee the long-term safety of the risk of the public or employees of the plant becoming Konrad once the repository has been sealed? ill is extremely low. Dr Wittwer: During the plan approval procedure, it was proven that at no point in time will radioactive material Final question: Would you move to Salzgitter after enter into the groundwater in a concentration that might 2013? present a danger to people and the environment. Starting Dr Kunze: Well, I wouldn’t make such a move dependent from extensive, geo-scientific forecasts of the long-term on the repository. I live only a short distance away, in development of the location, model calculations were Wolfenb¸ttel. I myself do not feel threatened there by used to estimate the migration of radionuclides from the repository in any way. Evidently, the waste will be put the repository into the near-surface groundwater and underground and will no longer be stored above ground – the potential exposure to radiation for people living in whether in a warehouse or anywhere else. That is clearly the surroundings of the repository. We are certain that a safer state of affairs than has previously been the the internationally accepted benchmark rate of 0.3 milli- case. Apart from that, I would be more likely to base my sieverts per year for the calculated effective dose will decision to move on whether I am living in proximity to a not be exceeded over the period of time in question. steel mill scenery, or more in the countryside. And a plant such as Konrad would cause me no concern in that. Will there be an increased risk of cancer? Dr Wittwer: I’m not looking to move again now, as I’m Dr Wittwer: Based on the current status of scientific quite happy where I live now. But I also don’t live that knowledge, we can assume that any exposure from ioni- far away from Konrad. I am confident that the Konrad sing radiation, whether from natural sources, additional repository will be operated in a safe and secure manner. exposure from technology or medical treatments, can have a damaging effect on people. It is for exactly this Thank you for your time.

interview 59 Appendix – Mining technology

Advance with road headers Conventional advance the rocks fall into the large borehole. Blasting a hole that The advantage of using mechanical advance with road Conventional advance involving drilling and blasting is is four metres long, six metres wide and five metres high headers compared to blasting is that the surrounding performed in a number of individual steps. To excavate produces about 300 tons of ore. rocks are affected to a lesser degree, the drift and gallery a drift with a cross-section of 30 sq. m. for example, a cross-sections can be more precisely excavated, and the bucket auger or flight-auger drilling rig first drills a cen- Roofbolting rate of advance is generally higher. When excavating, tral large-diameter borehole measuring about 40 centi- The appliance of a rational system of roofbolting is cru- this process has proved its worth in the majority of mine metres in diameter and about 4 metres deep. cial to securing workings when implementing trackless workings. Around the large-diameter borehole, a series of about conveying systems with large-scale diesel machines. The use of large-scale machines requires roadways with a With this method of advance, sections of the rock are 40 blast holes are then drilled with a blast hole drilling diameter that is at least double that for conventional cut using a cutter head comprising carbide bits that is rig and filled with explosives. Using an electrical system, procedures. This necessitates adjusting and improving attached to the road header. the explosives are detonated from the inside out so that the roofbolting system used in the Konrad mine, which has been able to adapt to every roadway profile since 1962.

All workings are stabilised with anchor bolts (at least one per square metre) and, if required for operational safety reasons, also with wire mesh. The anchor bolt is usually about 1.8 metres long. In special cases, it may even measure 2.5 metres in length.

Photo left: Under ground in Konrad 1. Photo right: Positioning chemical anchors with the drilling rig.

60 APPENDIX – MINING TECHNOLOGY 61 Glossary – an A – Z guide to Konrad

The aim of this glossary is to provide unequivocal terms Activity, specific: activity per unit mass: repository formation, surrounding rock or overlying and definitions that eliminate any misunderstandings and strata). Advance: mining excavation of cavities. therefore facilitate the development of a common langu- Barriers, technical: technical measures for preventing age which can be used in communicating issues relating Aerosol: suspended, very fine distribution of liquid or undue release of radioactive substances (for example solid substances in gaseous media. to the disposal of radioactive waste. waste product, packaging, backfill or mine seal). Air: air in the mine. Many of the terms are taken from other specialist fields Beta radiation: emission of positive or negatively char- Air exhaust shaft: opening for spent air from a mine. where they may have a different connotation. Readers ged electrons which result from the radioactive decay of will also be able to use this comprehensive glossary to Air tube: pipe that transports part of the airflow. a nuclide. look up terms they may come across during further rea- Alpha radiation: emission of alpha particles that com- Biosphere: that part of the Earth inhabited by living ding on the subject. prise two neutrons and two protons that are generated organisms.

Accident: course of events during which activity in and during the radioactive decay of a nuclide. In the process, Broken ore: rocks excavated through mining. operation of the facility must be discontinued for safety the atomic number decreases by two units and the mass Cage hoisting: mine conveyer system in which conveyor reasons, and for which the facility must be constructed, number by four. wagons are transported above ground by cages. or for which precautionary protection measures are to Auxiliary exhaust ventilation: supply of air via air tubes be taken. Cementing: fixing radioactive waste in a cement stone/ and blower fans to non-ventilated areas of a mine. concrete matrix. Activation: process whereby matter is rendered radi- Backfill: filling material used to fill or reduce the remai- oactive by being fired at by neutrons, protons or other Chamber: systematically excavated underground cavity. ning gaps in the cavities created during excavations or particles. during the storage of radioactive waste. Concession: a concession grants the sole right to mine Activity: the number of spontaneous nuclear transfor- natural resources in a specific field (area). However, fur- Bank: rock strata that is bordered by (strata) joints. mations of a radionuclide or radionuclide mixture in a ther permits are required to exercise this right. given time interval, divided by the length of the time Barriers: obstacles between the sources of ionising radi- Conditioning: the production of waste packages by pro- interval. The unit is the Becquerel (Bq). One Becquerel is ation and the biosphere. cessing or packaging radioactive waste. the number of radioactive decays in one second. Barriers, geological: geological realities for preventing Conservative calculations: calculations are conserva- Activity concentration: activity per unit volume. undue release of radioactive substances (for example tive if the boundary conditions and assumptions on which

62 they are based have been chosen so they exaggerate the Control areas: areas in which people who are there for the skin, hands, forearms, feet and ankles. Admittance is possible effects. 40 hours per week and 50 weeks per annum can receive usually restricted to persons who are required to carry an effective dose of more than 6 mSv, or an organ dose out or maintain the operating processes performed there. Contamination: pollution caused by radioactive subs­ of more than 45 mSv for the eye lens, or 150 mSv for tances. Convergence: natural process of volume reduction in underground cavities caused by rock pressure.

Conveyor track system: system for pushing flatbed wagons, arranged between rails.

Core drilling: drilling to extract a completely cylindri- cal body of rock with a diameter about the size of the borehole.

Crossway: a roadway that runs about parallel to the ex­- cavated deposit.

Crown: upper area of a roadway.

Decay chain, radioactive: the totality of radionuclides generated by radioactive transformations.

Decontamination: the cleaning through a chemical or physical process (such as washing or chemical treat- ment) of the surface of non-radioactive objects that have been polluted with radioactive particles. The decontami- nation of substance streams such as air or water is done using filters or by evaporation or precipitation.

Denudation: extensive erosion of the Earth’s surface, caused by water or wind, for example.

Depth: the distance under the surface.

Dip: degree of incline of rock strata from the horizontal by size and direction.

Radioactive waste is processed and packed in the conditioning plant.

GLOSSARY 63 to as the dose equivalent (roentgen equivalent) and taken by radioactive substances between being dis­- bears the abbreviation Sv (Sievert). The effective dose is charged from a plant or a facility via a dispersion or the sum of the weighted organ doses in the body tissue or transport, and which lead to radiation exposure among organ, which is caused by external or internal exposure. people, are described as relevant if– according to the current level of knowledge – they facilitate considerable Dose rate: the quotient derived from the dose and time. radiation exposure of persons either through incorpora- Dosimeter: instrument used to measure the ion energy tion (over the food chain), inhalation or through external or equivalent dose. exposure.

Effect, deterministic: radiation damage in which the Exposure: place where rock layers are made accessible. degree of the damage is a function of the dose. With View of a disposal chamber at the Konrad repository. This can be in the form of a natural exposure (e.g. bluff, many deterministic effects, there is a dose threshold precipice) or an artificial one (e.g. quarry, drilling). under which no clinical symptoms appear. Face (mining): 1. working surface for extraction. 2. late- Discharge of radioactive substances: the release of Effect, stochastic: radiation damage in which the pro- ral border of a mine. aerosol or gaseous substances from the facilities via the bability of damage occurring depends on the size of the prescribed means. dose. Facies: entirety of geological and palaentological fea- tures of a deposit. Disposal: the safe, maintenance-free free emplacement Emission: release, emanation, discharge.

of harmful substances without the intention of retrieval. Energy dose: absorbed amount of energy deposited by Fault zone (deformation/displacement): joint faces in Disposal chamber: workings with a diameter of 40 ionising radiation per unit mass. The unit is the Gray (Gy) rock mass at which bordering layers of rock are pushed square metres, for example, for disposing of radioactive (1 Gy = 1 J/kg). against each other (for example vertically displaced) waste. Epirogenic movement: tectonic process observed over during tectonic activity. a wide area within the Earth’s crust over a long geologi- Documentation: systematic compilation of documents. Field: space within which a mine owner holds the sole cal period of time, whereby the rock structure remains right to search for and extract minerals. The term is Dose equivalent: product of the energy dose and the intact. generally used for operational orientation within a mine. radiation weighting factor. The unit of measurement is Excavate: creation of a level or inclined drift or mine. the Sievert (Sv) (1 Sv = 1 J/kg). Filling: the process of using broken ore of an appropri- Exhaust air: stream of air behind an underground wor- ate grain size to pack disposal chambers and other mine Dose: radiant energy passed on to matter per unit mass king place which runs up to the exhaust shaft. areas, with the aim of minimising any remaining cavities. during interaction with ionising radiation. The types of Exploration: method of discovering deposits or of deter- radiant energy differ according to their biological effect. Fissile products: nuclides that are produced by fission, mining rock features and storage conditions of a geolo- To allow for these different effects, the energy dose is or by the ensuing radioactive decay of the nuclides direct gical body. multiplied by a weighting factor to give a new unit of resulting by fission. measurement for the dose which, for people, is referred Exposure pathway, relevant: those routes, which are

64 Fixation: hardening, embedding or sealing of pre-treated Formation waters: aqueous solutions from the geologi- only pass into the basic state after one or more gamma radioactive waste should the need arise. cal past that are stored in rock strata. quanta has/have been emitted. Even when capturing an electron from the K-shell, or through an inner conversion Fixing agent: material used for the fixation of radioac- Freight unit: containers and pool or transport pallets of the K-shell, high-energy, short-wave radiation (the tive waste. Examples include: glass, cement/concrete, loaded with waste packages. characteristic x-rays) is still emitted. bitumen or plastic. Fuel element: component containing fissile material that Geosphere: space running parallel to the Earth’s surface Flatbed wagon: idle roller, rail-mounted vehicle. forms a unit when loading and unloading a reactor. where parts of the Earth’s crust touch and penetrate the Fluviatile: elaborated, removed, deposited or enriched Gamma radiation: high energy, short wavelength radi- hydrosphere and the atmosphere. by rivers. ation emitted from an atomic nucleus. Gamma radiation Half life: characteristic time interval in which the activity frequently occurs in combination with alpha and beta Formation: a unit of rocks that genetically belong toge- of a nuclide falls to half its value. radiation and always in connection with nuclear fission ther. Used earlier only in the context of stratigraphy. as the resulting nuclei can energetically stimulated and Hanging wall: the rocks above a reference layer.

High consistency backfill: filling material made from broken ore won during the extraction phase and conver- ted to a high consistency pulp that subsequently hardens. It is used to fill the gaps that are created during opening or the storage of radioactive waste in the still open cavi- ties.

Incorporation: intake of radionuclides into the body.

Individual dose: quantity accumulated by one person in part or all of the body.

Inhalation: intake of radioactive substances into the human body through breathing.

Intensity: measure of local macro-seismic effects of an earthquake taking place on the surface of the Earth on people, buildings and the landscape. Intensity is classified using the 12-stage MSK 1964 scale (Medve- dev, Sponheuer, Karnik). The 12-stage macro-seismic intensity scale is known by the abbreviation MSK 1964

Filling the remaining cavities in the mine. (Sponheuer, 1965).

glossary 65 Carl Friedrich Koepe. sic (White Jurassic) around 156 to 140 million years ago. Large-diameter borehole: usually a borehole with a diameter greater than 65 millimetres which is made by Man-riding: the transport of persons inside the shaft rotary drilling. with the aid of the shaft conveyor devices.

Level: 1. all areas of the mine that are more or less at the Migration: the movement of water, solutions, oil and gas same depth. 2. the lowest area of a mine. through porous and permeable rock and rock strata.

LHD procedure: name given to a method of operation Mine: collective noun for all systematically excavated whereby rubber-tyre diesel loaders load (L) broken ore at underground cavities of a colliery. one place and haul (H) it to a mound where it is dumped Mine water: water entering the mine and having different (D) into a hopper or a chute hole. sources. Light water reactors: nuclear reactors that use natural Mineral deposits: areas in the Earth’s crust that are water (H20) to decelerate (moderate) fast neutrons and enriched with minerals. for heat dissipation; in contrast to heavy water reactors that work with heavy water (D20 deuterium oxide). A Mole: unit of measure to quantify substances (SI base distinction is made between pressurised water reactors unit). It is important in chemical reactions. (PWR) and boiling water reactors (BWR) depending on Nuclear fuels: fissile material in the form of uranium as the design. a metal, alloy or chemical compound (including natural

Line of bearing: direction of the intersecting line in a uranium) and in the form of plutonium as a metal, alloy geological area with the horizontal level, based on a nort- or chemical compound. The mine shaft conveyor. herly direction. Nuclear fuel cycle: all operations involving the supplying and disposal of nuclear fuel to and from nuclear reactors, Iodine-129: iodine-129 is a radioactive isotope of the Loading area: transition zone from shaft to mine. the mining of uranium, fuel enrichment, the production of iodine element with a half life of about 16 million years. Local dose: dose equivalent for soft tissue measured at fuel elements, reprocessing of spent fuel, storage of fuel Its atomic nucleus contains the same number of pro- a specific location. elements and the disposal of radioactive waste. tons as that of the stable iodine-127, but possesses two Local dose rate: external radiation to which a person is neutrons more and decays by emitting a beta particle. Nuclide: atoms are made up of a nucleus and an electron exposed depending on the time and place. It is given in Iodine-129 does not occur naturally. cloud; the parts of the nucleus (neutrons and protons) nSv/h (nano Sievert per hour). are called nucleons; atoms are classified according to Joints: cracks in the rock caused by tectonic activity. Locker room: washing and changing room. the numbers of protons and neutrons they have, and are Koepe machine: hoisting system with sheave invented by known as nuclides. Malm: name for the time period of the Early Juras-

66 inasmuch that there are no safety relevant reasons for discontinuing operations (abnormal operations); 3. main- tenance procedures (inspection, service, repairs).

Packaging: all parts of a non-reusable receptacle used to encase a waste product.

Pellet: solid radioactive waste that has been compressed with high pressure in a metal cartridge or drum, if neces- sary.

Permeability: the ability of rock to allow liquids and gases to pass through it.

Petrography: branch of science dealing with the com- position of rocks, their natural occurrence, behaviour in relation to one another as well as their formation and transformations.

Pillar: an area of mineral deposit left between the mine workings which is not mined and guarantees cohesion of the rock mass.

Pillar-and-breast work: excavating method for creating chambers.

Plan approval resolution: in Germany, the plan appro-

Example of mine workings: an underground repair shop. val is a (formal) administrative procedure in federal and state administrative law in which the authorities

Oolite: sedimentary rock made up of numerous ooids. when parts of the facility or systems malfunction (dis­ bindingly sanction a plan. The plan approval replaces all other decisions by authorities, in particular public per- An ooid is defined as spherical concentric accretions of rupted state) inasmuch that there are no safety relevant mits, concessions, licences and approvals. It possesses a calcium carbonate or other substances around a crystal reasons for discontinuing operations. concen­tration effect. nucleus. Operation, normal: This includes: 1. sequences of opera- Pool pallet: reusable device for conveying cylindrical tion for which the facility – when fully functional (undis- Opening: mining activity for systematically mining use- waste packages. rupted state) – is intended and suited (standard opera­ able material. tions); 2. sequences of operation which occur when parts Porosity: the overall volume of rock is made up of the Operation, abnormal: operating processes which occur of the facility or systems malfunction (disrupted state) volume of its solid substances and the volume of the

glossary 67 cavities or pores in the rock. The overall porosity is refers to radiation exposure caused by radiation sources Raw waste: unprocessed radioactive waste. defined as the ratio of the pore volume to the overall within the body. Receiver: natural (river, stream) or man-made (canal, volume of the rock. The effective porosity is defined as Radiation protection: measures taken to protect people pump station) means or discharging wastewater. the ratio of the pore volume that can be used for conduc- and the environment from the damaging effects of ioni- ting water to the overall volume of the rock. Release: discharge of radioactive substances from areas sing radiation. that are closed off by one or more barriers, for example Post-operational phase: time following the decommissi- Radiation weighting factor: coefficient used to weight from a waste product, waste package, disposal chamber oning of the repository mine. the differing biological effects of different types of radia- or repository. Product control: proof that all conditions relating to the tion when assessing the dose equivalent. Reloading hall: hall for receiving freight units on goods disposal of waste packages have been fulfilled. Radiation, ionising: all radiation, which directly or indi- wagons or lorries, or for consigning pool pallets to goods Radiation exposure: the impact of ionising radiation rectly ionises, for example alpha, beta, gamma and neu- wagons or lorries. tron radiation. on the human body. Whole body exposure refers to the Reprocessing: the application of chemical processes impact of ionising radiation on the entire body. Partial Radioactivity: process of spontaneous decay of atomic through which, after use in the reactor, recyclable waste body exposure refers to the impact of ionising radiation nuclei, so-called radionuclides, that takes place with no – the remaining uranium and the fissionable material plu- on specific body parts or organs. External radiation expo- external influence. Radionuclides transform to other tonium – present in the spent nuclear fuel is separated sure refers to radiation exposure caused by radiation nuclides, releasing alpha, beta and gamma emitters in from the fissile materials, radioactive waste. sources outside the body. Internal radiation exposure the process. Radionuclides can occur naturally and be Rim syncline: subsidence area at the edge of a salt dome generated through nuclear processes. caused by the migration of salt in the salt dome. The iron Radionuclide: instable nuclide that decays spontane- ore deposits of the Upper Jurassic have formed in this ously with no external influence, emitting radiation in the type of syncline. process. More than 1,200 natural and artificial radionu- Risk: here, the probability of developing a severe illness clides are known to exist. (tumour, genetic disorder, etc.) during the course of a Radium-226: radium-226 is a radioactive isotope of lifetime, which has been caused by radionuclides relea- the radium element with a half life of about 1,600 mil- sed from the repository. lion years. Its atomic nucleus contains 88 protons and Road header: advancing machine for excavating mines 138 neutrons and emits an alpha particle during decay. by working the face in sections. Although no stable radium isotopes exist, radium-226 is part of the natural uranium decay series in nature. Roadway: tunnel-like construction in a mine, which is excavated relatively level. Ramp: mainly straight connection for travelling between

A product control station. the levels. Roofbolting: ready-made steel or glass fibre plastic rods

68 that are inserted into boreholes where they are fixed and Seismicity: frequency and intensity of earthquakes in a Sink: the creation of a vertical mine such as a shaft or used to ‘knit’ the rock mass together. region. borehole using differing methods such as blasting or

Salt dome/Salt diapir: vertical mass of salt found at Shaft house: the building around the shaft. drilling. depth that breaks through the overlying strata, brea- Shield: device that surrounds a source of ionising ra-­ Sorption: process in which another solid or liquid ching the Earth’s crust at its weaker areas. diation to protect the surrounding area from its radiation. substance takes up a gaseous or dissolved substance. Salt pillow: flat, dome-shaped salt bed. Side stacker: vehicle used for handling freight units Spiral: vehicle-accessible connection between levels Sealing: separation of the filled storage cavities from the between the reloading hall and the buffer hall. that corkscrews to overcome height differences. open mine with dams. Stacker: vehicle used for transporting freight units from the unloading chamber to the storage location and for stacking the waste packages.

State collecting points: according to the Atomic Energy Act, the federal states are required to provide collecting points for the interim storage of all the radioactive waste that the individual state produces in research facilities, universities, business enterprises and industrial plants, hospitals or doctors’ surgeries.

Stratigraphy (study of rock strata): the theory of the sequence of rock layers and formations as well as their chronological classification.

Subrosion: underground decomposition of aqueous rock caused by groundwater.

Total activity: the number of decays per unit of time which occur in radioactive waste.

Transgression: advance of the seas over large expanses of mainland.

Transport pallet: pool pallet with a protective cover.

Mechanical advance with a road header. Underlaying: the rock below a reference stratum.

glossary 69 Waste product group: waste products that behave in a similar way with regard to the release of radioactive substances.

Waste product: processed radioactive waste without packaging or also unprocessed radioactive waste that is packaged in a receptacle. Waste products are safely stored in these barrels.

Waste receptacle category: encompasses waste recep- tacles that behave in a similar way with regard to the release of radioactive substances.

Waste receptacle: receptacle used for a waste product (e.g. barrel, concrete canister, cast-iron cask, container). Mining work at the Konrad mine. Waste water: water from the facility that is intended for discharge or which has been discharged.

Waste products are safely stored in these barrels. Waste, radioactive: radioactive substances as defined under Section 2, sub-sections 1 & 2 of the Atomic Energy

Unloading chamber: reloading area between the Act (German), which – in accordance with Section 9a, transport wagon and the stacker. sub-section 1 (2) of the Atomic Energy Act, must be duly disposed of. Upright: vertical. Wire mesh: wire netting fixed to the walls and ceilings of Ventilation: scheduled supply of fresh air to the wor- the mine to prevent rocks dislodging from them. kings. Working homewards: the disposal galleries are excava- Ventilation: systematic method of diverting air through the mine. ted and then filled from back to front with radioactive waste packages. The galleries are then sealed. Waste disposal conditions: requirements that are deter- mined for the disposal of waste packages based on the Working place: underground area where mining work is location-specific realities. performed, for example, heading, excavation or transfer point. Waste package: unit of waste product and waste receptacle that is to be disposed of. Working: systematically excavated underground cavity.

70 Contact and Publication Details

Would you like to inspect a mine shaft? Would you Published by: like to visit the InfoKonrad information centre as a The Federal Office for Radiation Protection party? Edited by: Do you have further queries or require additional infor- The Federal Office for Radiation Protection, mation? We look forward to answering your questions. Info Konrad, Melanie Bartholomäus

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Last revised: October 2008

CONTACT AND PUBLICATION details 71 Publisher: InfoKonrad Bundesamt f¸r Strahlenschutz Chemnitzer Strasse 27 Postfach 100149 38226 Salzgitter, Germany 38201 Salzgitter, Germany Phone +49 (0)5341 867 3099 Phone +49 (0) 30 183 33-0 Fax +49 (0) 3018 333 1285 Fax +49 (0) 30 183 33-1885 [email protected] [email protected] · www.bfs.de www.endlager-konrad.de

From: Peter Brennecke To: Myles,Debra [CEAA] Cc: [email protected]; [email protected] Subject: Visit of the Review Panel Date: August 24, 2012 4:42:48 PM Attachments: WM "11_11442.doc

Dear Ms. Myles, in reply to your today's e-mail I would like to inform you that the material I sent by mail is not available in electronic form. There are not that much documents on the Konrad repository being available in English language and in electronic form. Most of them have been prepared for international conferences and symposia. To your information I enclose a paper (including information on Konrad facility) which I presented at the Waste Management 2011 conference in Phoenix/USA.

I appreciate the intention to send letters to Dr. Tietze of BfS as well as to Mr. Bluth and Dr. Pick of NMU. As requested I would like to verify that the correspondence should only be sent electronically and not by mail.

Finally, I would like to confirm that it is still possible for the Review Panel to visit the Konrad repository on October 17, 18, 19 or 23-26, 2012. Nevertheless, the decision on the final date should be made as soon as possible.

With best regards,

Peter

-- Dr. Peter Brennecke WM 2011 Conference, February 27 - March 3, 2011, Phoenix, AZ

Radioactive Waste Disposal Challenges in Germany - 11442

Peter W. Brennecke

Bundesamt für Strahlenschutz, Salzgitter, Germany

ABSTRACT

In the Federal Republic of Germany the disposal of all types of solid and solidified radioactive waste in deep geological formations is still the preferred option. Actual principal issues in radioactive waste disposal are focused on activities further developing and detailing the German radioactive waste disposal concept as well as particularly on activities concerning the operation of the Konrad, Gorleben, Morsleben and Asse II sites. Of this, the draft Safety Requirements on the Disposal of Heat- Generating Radioactive Waste dated September 2010, the construction of the Konrad repository for low-level and intermediate-level radioactive waste, the preparation of disposal room investigations in the Asse II mine the results of which will serve as the essential prerequisite for the decision on waste retrieval / recovery, as well as the termination of the Gorleben Moratorium and the resumption of underground explorations of the Gorleben salt dome are the most important topics.

INTRODUCTION

Radioactive waste disposal policy in the Federal Republic of Germany is based on the Government decision that all types of radioactive waste with short-lived and long-lived radionuclides are to be disposed of in deep geological formations within the country. This decision entails the necessity to condition (i.e., to process and to package) the waste. Only solid and solidified radioactive waste is accepted for disposal; liquid and gaseous radioactive waste is excluded from disposal except when appropriately be conditioned. In Germany, radioactive waste disposal is a federal task the Atomic Energy Act giving the responsibility to the Federal Government with the Federal Ministry for Environment, Nature Conservation and Nuclear Safety (BMU - Bundesministerium für Umwelt, Naturschutz und Reaktorsicherheit) as competent ministry, and - within the portfolio of BMU - the Federal Office for Radiation Protection (BfS - Bundesamt für Strahlenschutz) as the legally responsible authority for performing this task.

RADIOACTIVE WASTE ARISINGS

According to the German approach to disposal, radioactive waste is basically subdivided into waste with negligible heat generation (i.e., low-level waste (LLW) and intermediate-level waste (ILW)) and heat-generating waste (i.e., high-level waste (HLW) and spent nuclear fuel (SNF)). Radioactive waste with negligible heat generation comprises all types of radioactive waste originating from the operation, decommissioning and/or dismantling of nuclear facilities, e.g., nuclear power plants, reprocessing facilities, nuclear industry, research and development establishments, as well as smaller waste generators such as hospitals, industry and universities. Heat-generating radioactive waste comprises in particular waste originating from reprocessing such as vitrified fission product solution and high- pressure compacted hulls and ends, as well as spent nuclear fuel when declared to be waste. As to radioactive waste arisings, BfS carries out on annual inquiry into the amounts of radioactive waste in Germany. According to the latest inquiry, about 20,700 m3 of radioactive residues, about 8,200 m3 of preconditioned waste and about 100,000 m3 of conditioned waste with negligible heat generation (i.e., LLW and ILW) had been accumulated by the end of December 2009. The amount of unconditioned/preconditioned and conditioned heat-generating waste (i.e., HLW and SNF) by the end of December 2009 was about 1,300 m3 and about 600 m3, respectively (without spent nuclear fuel). The amount of conditioned heat-generating waste comprises vitrified waste already repatriated from reprocessing German spent fuel in France.

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Forecast waste amounts for the future are for approximately 280,000 m3 of conditioned waste with negligible heat generation and for approximately 28,000 m3 of conditioned heat-generating waste accumulated up to 2080.

DEVELOPMENTS OF THE GERMAN DISPOSAL CONCEPT

In Germany, principal issues in further developing and detailing the radioactive waste disposal concept comprise in particular the Safety Requirements on the Disposal of Heat-Generating Radioactive Waste and the finalisation of activities concerning the comparison of potential repository sites, i.e. the VerSi project.

Safety Requirements on the Disposal of Heat-Generating Radioactive Waste

Disposal of heat-generating radioactive waste is still a great challenge. So far, no repository specifically for heat-generating radioactive waste is world-wide in operation. Safety requirements for the disposal of heat-generating radioactive waste provide the safety-related framework that must be complied with in planning, constructing, operating, decommissioning and sealing a repository for this type of waste. In Germany, the then responsible Ministry for the Interior (BMI - Bundesministerium des Innern) published in 1983 the “Safety Criteria for the Disposal of Radioactive Waste in a Mine” [1].

The safety criteria of 1983 had to be revised with respect to the present state of science and technology and to latest international recommendations. The Company for Plant and Reactor Safety (GRS - Gesellschaft für Anlagen- und Reaktorsicherheit mbH) was charged by BMU with the preparation of a proposal for an update of the 1983 safety criteria. The GRS draft proposal of January 2007, which was intensively supported by BfS, considers both the further development of the state-of-the-art of science and technology as well as international recommendations published in particular by IAEA and ICRP most recently [2]. Its main features are the isolation of the heat-generating waste in the isolating rock zone, demonstration of safety (i.e., appropriate containment of radionuclides) for approximately one million years, conducting a stepwise approach, and executing a continuous safety- related optimization process.

On the basis of this draft proposal, its scientific discussion in a 2007 workshop on Safety Requirements on the Final Disposal of High-level Radioactive Waste, and a BfS statement [3] requested by BMU, the competent Federal Ministry started the preparation of the safety requirements on the disposal of high-level radioactive waste in deep geological formations. The elaboration of this important document was accompanied by further discussions with experts and the public, in particular in a 2008 International Radioactive Waste Disposal Symposium organized by BMU and a second workshop in 2009. In parallel to that, the draft documents were examined and evaluated in detail by the advisory bodies of BMU, i.e, the Reactor Safety Commission (RSK - Reaktor- Sicherheitskommission) and the Radiation Safety Commission (SSK - Strahlenschutzkommission), later on by the Waste Management Commission (ESK - Entsorgungskommission). Finally BMU issued the "Safety Requirements Governing the Final Disposal of Radioactive Waste" as of July 2009 [4], available at http://www.bmu.de/english/nuclear_safety/downloads/doc/44839.php. These requirements do address and regulate the following topics:

- Protection objectives.

- Safety principles.

- The step-by-step approach and optimization with respect to radiation protection, operational safety and reliability of the safe long-term containment/isolation of radioactive waste.

- Protection from damage caused by ionising radiation.

- Safety assessments and proof of operational and long-term safety (safety cases).

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- Repository design requirements.

- Safety management.

- Documentation.

Subsequent to the July 2009 draft document, further discussions in particular with representatives of the Federal States (Länder) took place as well as the elaboration of a follow-up was performed by BMU resulting in the current September 2010 draft. According to this document essential adaptations and adjustments with respect to hitherto existing planning work concerning the disposal of heat- generating radioactive waste in rock salt are to be expected [5]. This is most notably due to the requirements that now

- the retrievability of the waste packages must be possible during the operational phase of the repository, and

- the recovery of the waste packages as a measure of an emergency situation must be possible for a period of time of 500 years after closure and sealing of the repository.

In particular, the requirement on the recovery of waste packages does mean a 500 years waste container lifetime or an appropriate waste package emplacement method ensuring their integrity during this period of time - a requirement which is controversially being dealt with. Nevertheless, BMU will continue the discussions with advisory bodies, experts, the public as well as with representatives of the Federal States [5]. Thus, the final preparation and publication of the Safety Requirements on the Disposal of Heat-generating Radioactive Waste, e.g., in the Federal Gazette, are still pending.

Comparison of Potential Repository Sites - The VerSi Project

Within the framework of political discussions and provisions on a revision of the German radioactive waste disposal concept it was suggested that, in addition to the Gorleben site, further sites in various host rocks had to be investigated for their suitability to host a repository. The final site should be selected on the basis of a safety-related comparison of potential sites, including the Gorleben site.

Such a comparison of different sites, i.e. different host rock formations such as salt, clay and granite, had previously not been carried out in Germany or elsewhere. Thus, BfS launched in 2006 the project Comparative Safety Assessments for Repository Systems to Evaluate Methodologies and Instruments (Vergleichende Sicherheitsanalysen für Endlagerstandorte zur Bewertung der Methoden und Instrumentarien) - the VerSi Project. The objective of this project is to enable a comparison of repository sites in different host rocks and to provide appropriate means. Therefore, the safety- analytical instruments and methodologies for a comparison of different repository sites are to be developed and tested accordingly. Work is being performed on the basis of long-term safety assessments taking into account geoscientific databases, radioactive waste inventories, corresponding disposal concepts, as well as appropriate backfilling and closure concepts.

The method should be developed by applying data that are as close to reality as possible. This includes repository concepts as well as site-specific parameters. However, it is not intended to prove the long- term safety of the studied site cases within the VerSi Project. The method is focused on long-term safety assessments in the post-operational phase of a repository. The operational phase of a repository, data uncertainties, the optimisation of the repository, and human intrusion issues remain unconsidered in the development of the method. Thus, within the VerSi Project, only a part of a complete comparison is considered, namely the comparison of safety assessments under given simplifying boundary conditions. Also, socio-scientific and planning-scientific aspects cannot be taken into account in this method development.

Within the scope of the VerSi Project, rock salt and clay stone are examined as potential host rocks. These host rocks exist in Germany and, due to the AkEnd recommendations [6], are basically

WM 2011 Conference, February 27 - March 3, 2011, Phoenix, AZ considered suitable to host a repository for heat-generating radioactive waste. For testing the tools, a HLW repository hosted in a salt dome (Gorleben) will be compared with a generic HLW repository in consolidated clay as host rock. Since in Germany no clay site has been investigated for hosting a HLW repository until now, the required data for comparison are transferred from international research projects and repository concepts. The VerSi Project does not comprise any geoscientific exploration at a distinct site nor a long-term safety analysis for a distinct site or a site selection itself.

As a result, two distinct and complementary methods were developed for the comparison of sites. The first one is a Verbal Argumentative Method in which the probabilities of occurrence of features, events, and processes (FEPs) are evaluated by the determination of weighting factors for the relevance and the robustness of safety functions in different time windows). The second one is a Probabilistic- calculations Based Method in which the consequences of FEPs are evaluated by comparing statistical measures of probabilistic calculations.

At present, there is no decision on the implementation of a site selection procedure [7]. Even in case that a comparison of potential repository sites within such a procedure will not be performed, the VerSi project supplies a sound basis for those tasks to be faced in future regarding the performance of preliminary safety assessments. Thus, the results of this project will serve as an important safety- related tool in future decision making.

DISPOSAL OF RADIOACTIVE WASTE

An outline of the most relevant activities concerning the operation of the Konrad, Gorleben, Morsleben and Asse II sites is provided in the following section.

The KONRAD Repository

The abandoned Konrad iron ore mine, located in the Federal State of Lower Saxony (Niedersachsen), was investigated for the disposal of all types of short-lived and long-lived radioactive waste with negligible heat generation, i.e., waste packages which do not increase the host rock temperature by more than 3 K on an average (low-level and intermediate-level radioactive waste (LLW and ILW)). The most essential waste-related planning data comprise an emplacement of waste packages up to 650,000 m3 with a total beta/gamma activity of 5.0 x 1018 Bq and an alpha emitter activity of 1.5 x 1017 Bq. Waste packages are intended to be emplaced at a depth of 800 m to 1,300 m in disposal rooms with a cross-section of 40 m2 and a length of up to 1,000 m using the stacking technique.

The licensing procedure for the Konrad repository was started on August 31, 1982. The license was issued on May 22, 2002, for the emplacement of waste packages of 303,000 m3 at maximum. Of this, approximately 150,000 m3 will originate from the operation as well as from the decommissioning and dismantling of various nuclear facilities, respectively. The operational lifetime is expected to last for 30 or 40 years - a respective decision is still to be taken.

The license was immediately sued by several municipalities and private persons, i.e. challenged in court. It became unappealable on March 26, 2007, after non-acceptance of all claims and rejection of all appeals lodged against it by the Federal Administrative Court. On May 30, 2007, BMU charged BfS with the conversion of the Konrad mine into a repository. The main operating plan according to the Federal Mining Law for the construction of the Konrad repository was approved on January 15, 2008.

Subsequent to comprehensive preparatory measures and plannings the actual construction work started in the beginning of October 2009, i.e. by the assembly of new cable trays in drifts and galleries as well as cable-laying. With respect to shaft area Konrad 1, several buildings were demolished and will be newly constructed. The hoisting plant is being re-constructed. As to shaft area Konrad 2, nearly all buildings were demolished. For shaft transport an auxiliary hoisting plant was constructed and taken into operation. Prior to the start of above-ground construction work explosive ordnance clearance with subsequent remediation took place and was recently finished. Preservation and

WM 2011 Conference, February 27 - March 3, 2011, Phoenix, AZ reconstruction work for both shafts Konrad 1 and Konrad 2 are pushed. Underground activities are focused on the reconstruction of infrastructure galleries as well as on preparatory measures to excavate the disposal rooms of emplacement field 5/1 and subsequent excavation.

In addition to the actual construction work additional requirements imposed by the licensing authority in the Konrad license are to be realized and implemented. Thus, the Konrad waste acceptance requirements [7] and the measures for waste package quality assurance/quality control are being revised and intended to be published in spring 2011.

At present, the time schedule for constructing the Konrad repository is intensively being discussed and adjusted to actual planning necessities and, in particular, to interdependencies on contractors and, in particular, on other authorities involved. A very important problem immediately to be solved concerns the appointment of the competent authority being in charge for examining and licensing building applications. Different opinions between the competent Lower Saxonian ministry and the Salzgitter city building authority cause severe delays. At the end of this process reliable information on the construction period of the Konrad repository will be available. As a prerequisite to the actual start of operation, numerous test operations will have to be successfully performed.

Continuous and comprehensive information of the public on all aspects of constructing the Konrad repository is ensured by BfS.

GORLEBEN Exploration Mine

Since the end of the 1970s, the Gorleben salt dome, located in the northern part of the Federal State of Lower Saxony (Niedersachsen), has been investigated for its suitability to host a repository at depths between 840 m and 1,200 m for all types of radioactive waste, in particular for heat-generating waste originating from reprocessing and for spent nuclear fuel elements (direct disposal). The accumulated inventory of beta/gamma and alpha emitters was planned to be in the order of magnitude of 1021 Bq and 1019 Bq, respectively. Site-specific investigations were started in 1979. The above-ground investigation programme was finished and two shafts were completed. The underground investigation of the Gorleben salt dome was in progress, in particular the first exploration area (EB1 - Erkundungsbereich 1) in the north-eastern part of the Gorleben salt dome.

With the beginning of the Gorleben Moratorium, the underground exploration by heading, exploration drillings, and geotechnical measurements was stopped on October 01, 2000, and remains suspended up to now. Since that time only measurements and work have been carried out that are necessary to ensure mining safety and for operational reasons to maintain the exploration mine in a reliable state.

As a result of the latest federal elections which took place on September 27, 2009, a coalition of the Christian Democratic Parties (CDU and CSU) and the Liberal Democratic Party (FDP) came into power. The political aims of the Federal Government are given in the coalition agreement of CDU/CSU and FDP dated October 26, 2009 [8]. With respect to the Gorleben repository project the coalition partners have agreed upon the following:

- Immediate termination of the Gorleben Moratorium.

- Open-ended continuation of the Gorleben salt dome exploration.

- International Peer Review Group to accompany the Gorleben exploration work.

The Gorleben Moratorium ended on September 30, 2010. Since then main activities are concentrated on the performance of a preliminary site-specific safety assessment and the resumption of underground exploration work.

According to BMU a preliminary safety assessment for the Gorleben site including the hitherto available results of the underground exploration and an optimized repository concept is being carried

WM 2011 Conference, February 27 - March 3, 2011, Phoenix, AZ out by GRS. This assessment is targeting the question if a repository for heat-generating radioactive waste may be hosted by the Gorleben salt dome. In addition, necessary investigations and underground explorations for the determination of lacking geo-scientific and safety-related data are to be identified. Main topics to be investigated focus on the questions how reliable the predictions on the behaviour of the repository system are and what issues remain unsolved - hence needing future research and exploration. Work started in March 2010 and shall be finished in 2012. The envisaged international peer review process serves to check and to evaluate whether the safety assessment and its results are in line with the current state-of-the-art in science and technology. It cannot be excluded that this process may result in more detailed recommendations and requirements on future research and exploration work.

In parallel to the safety assessment BfS prepared the resumption of underground exploration work with respect to staff, machinery and mine ventilation. In parallel, BfS applied for the main operating plan which was approved by the Board of Mines in September 2010, i.e. prior to the termination of the Gorleben Moratorium. Thus, the re-start of investigating the Gorleben salt dome took place on November 11, 2010, with EMR measurements on the 840 m level. Underground excavation activities restricted to the northern drift way followed on December 03, 2010.

Regarding the public the development of a new information system has been initiated.

The results of the Gorleben preliminary safety assessment and the work of the international peer review group will form the basis for BMU to decide on the continuation of the Gorleben repository project or its abandonment.

MORSLEBEN Repository

Since 1971, low and intermediate level radioactive waste with mainly short-lived radionuclides and an alpha emitter concentration of up to 4.0 x 1011 Bq/m³ originating from the operation of nuclear power plants and the application of radioisotopes in research, medicine and industry in the former German Democratic Republic was disposed of in the Morsleben repository, an abandoned salt mine re-used for radioactive waste disposal. This facility is located in the western part of the Federal State of Saxony- Anhalt (Sachsen-Anhalt), very close to Niedersachsen. Since German unity on October 03, 1990, this facility has the status of a federal repository. Operated by BfS as licensee the Morsleben facility received radioactive waste from a broad range of origins and/or sources, in particular from nuclear power plants, research establishments and from smaller waste generators. From 1971 through 1998 radioactive waste with a total volume of about 36,800 m³ including about 6,600 spent sealed radiation sources was disposed of. The total activity of beta/gamma emitters amounts to about 5.0 x 1014 Bq (relating to 2005), that of alpha emitters to about 7.5 x 1011 Bq. According to September 25, 1998, as the result of a court order, BfS had to immediately stop further radioactive waste disposal in the eastern emplacement field. Thus, last waste emplacement operations were carried out on September 28, 1998.

The Morsleben repository will not resume emplacement operations. BfS stated on April 12, 2001, that this facility will definitely never again be used for radioactive waste disposal (renunciation of those parts of the Morsleben repository operation license dealing with the emplacement of radioactive waste). An application for the licensing procedure for decommissioning and closure was already filed on October 13, 1992. On May 09, 1997, BfS renewed this application. The main licensing document, the so-called Plan, has been provided - together with the Environmental Impact Assessment and further important documents - to the competent regulatory body (licensing authority) on September 13, 2005, and - in revised version - on January 26, 2009. On October 15, 2009, the involvement of the public started and the respective documents on the closure of the Morsleben repository were made available to the public from October 22 to December 21, 2009. In total, about 12,000 objections have been raised on the planned closure and sealing of the Morsleben repository. At present, these objections are being dealt with in order to prepare the public hearing. According to the competent licensing authority, this hearing may take place in fall 2011.

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As to the closure of the Morsleben repository, it is planned to backfill large parts of the underground facilities and the shafts. The emplacement areas will be sealed by specially tailored dams in the access galleries. Altogether, the concept provides for an amount of backfill of about four million cubic metres of salt concrete. The shafts will be sealed with special shaft sealing materials. Backfilling and sealing are anticipated to last for about 15 years. Closure costs will probably amount to approx. 1.2 billion Euro.

With respect to closure, a very important measure is the backfilling of the highly excavated central part of the Morsleben repository. The backfilling of selected rooms of this part, which has not been used for radioactive waste disposal, is being undertaken to enhance geomechanical stability and integrity. Thus, an important safety-related prerequisite with respect to the future backfilling and sealing of the Morsleben repository will be provided by this action. The backfilling measures using a specifically tailored salt concrete were carried out from October 2003 until November 2009. In total, 24 rooms with a volume of approx. 800,000 m3 were backfilled.

For further enhancement of geo-mechanical stability, the additional backfilling of three rooms has been started and is expected to be finished in February 2011. The volume of backfill material needed is estimated to amount to approx. 150,000 m3.

ASSE II Repository

In the Asse II repository, a re-used salt mine located in the Federal State of Lower Saxony (Niedersachsen), about 125,000 drums of LLW were emplaced in 12 chambers at depths from 725 m to 750 m and about 1,300 drums of ILW in a chamber at a depth of 511 m from 1967 until 1978. The total activity inventory amounts to 3.1 x⋅ 1015 Bq (as of January 01, 2002), about 40 % of the inventory being contained in ILW. Subsequent to waste emplacement, the Asse II mine served as underground research laboratory until the decision on its closure was made.

In 1988, in the range of the southern flank at the 537 m level, a first influx of salt solution was observed. It was triggered by movement of the salt rock strata induced by former mining activities. The solution, which presently enters at a quantity of 12.5 m³ per day [9], is fully collected and pumped to the surface. In order to stabilise the mine, old chambers in the southern flank were filled between August 1995 and December 2003. A total of about 2.1 million Mg (corresponding to 1.75 million m³) backfill material was inserted into the southern flank of the Asse II mine.

Insufficient information of the public, deficiencies in radiation protection issues, and lacking transparency in the planning of the Asse II closure gave rise to more and more criticism. Finally, on September 04, 2008, the competent Federal Ministries BMU and BMBF and the Ministry for the Environment and Climate Protection of Lower Saxony (NMU - Niedersächsisches Ministerium für Umwelt und Klimaschutz) agreed that BfS should take over responsibility for the decommissioning as future operator. The Asse II mine would be subjected to the legal procedure applying to repositories according to the Atomic Energy Act (AtG - Atomgesetz).

Since January 01, 2009 the Asse II mine has been under the responsibility of the BfS. The mine is run by the Asse GmbH which was founded at the beginning of 2009.

Initial BfS activities were focused on the improvement of radiation protection issues and on the salt solution management. Measures to improve the safety situation of the mine are performed by stabilizing of the southern flank by means of backfilling roof clefts. In the process of this measure, the cavities having occurred in the chambers of the southern flank due to the backfill material’s large pore volume are backfilled with special Sorel concrete. The backfilling of roof clefts has started in the beginning of December 2009.

With respect to the final closure concept for the Asse II facility complementary and alternative closure concepts were prepared and evaluated. A basic decision was made on January 15, 2010. Accordingly, BfS’ designated closure concept focuses on the retrieval / recovery of the waste packages disposed of.

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Nevertheless, there exist uncertainties on the actual status of the emplacement chambers and of the waste packages as well as on the possibilities to handle the waste packages. Thus, in order to clarify these uncertainties, BfS is preparing underground investigations of two selected emplacement chambers on the 750 m level (chambers 7/750 and 12/750). This will be done in a stepwise process, starting with drilling activities, followed by the opening of the emplacement chambers and a tentative retrieval of waste packages for test purposes. Test operations were already successfully performed. The start of actual drilling activities is expected in the first half of 2011.

In parallel to the underground investigations, comprehensive planning work is performed to prepare the retrieval of all waste packages. This includes planning work for sinking a new shaft, the construction of radioactive waste conditioning and storage facilities as well as the construction of necessary technical facilities and infrastructure areas underground.

Final decisions on the closure of the Asse II repository which will in particular reflect the results of the emplacement chamber investigations are still to be taken.

THE WAY AHEAD

In view of the current German situation on radioactive waste management it has to be stated that progress is definitively notable on waste disposal. The construction and future operation of the Konrad repository will ensure the emplacement of nearly all low-level and intermediate-level waste arising in Germany. The preparation of the Safety Requirements on the Disposal of Heat-Generating Radioactive Waste and the various Gorleben-relevant activities are aiming at advancements and improvements with respect to heat-generating radioactive waste disposal.

REFERENCES

1. Bundesministerium des Innern, "Sicherheitskriterien für die Endlagerung radioaktiver Abfälle in einem Bergwerk", Bundesanzeiger 35 (1983) no. 2, p. 45-46.

2. B. BALTES, and P. BRENNECKE, "Safety Requirements on Heat-Generating Radioactive Waste - Ongoing Development Process of Regulations", Proc. Int. Conf. Radioactive Waste Disposal in Geological Formations, Braunschweig, Germany, November 06-09, 2007, GRS-S-49, Bundesamt für Strahlenschutz/Gesellschaft für Anlagen- und Reaktorsicherheit (GRS) mbH (2008).

3. P. BRENNECKE, T.JUNG, U. KLEEMANN, H. KLONK, C. WITTWER, and J. WOLLRATH, "Sicherheitsanforderungen an die Endlagerung hochradioaktiver Abfälle in tiefen geologischen Formationen", report SE-IB-20/07, Bundesamt für Strahlenschutz (2007).

4. Bundesministerium für Umwelt, Naturschutz und Reaktorsicherheit, "Safety Requirements Governing the Final Disposal of Heat-Generating Radioactive Waste", BMU (2009). http://www.bmu.de/english/nuclear_safety/downloads/doc/42047.php

5. G. ARENS, "Sicherheitsanforderungen an die Endlagerung wärmeentwickelnder radioaktiver Abfälle", TÜV NORD EnSys Hannover GmbH & Co. KG/TÜV NORD Akademie GmbH & Co. KG, Proc. 4. Symposium Stilllegung und Rückbau kerntechnischer Anlagen/6. Symposium Lagerung und Transport radioaktiver Stoffe, Hannover, Germany, November 02-03, 2010, TÜV NORD, Hannover (2010).

6. Arbeitskreis Auswahlverfahren Endlagerstandorte (AkEnd), "Site Selection Procedure for Repository Sites", AkEnd (2002).

7. P. BRENNECKE, "Requirements on Radioactive Waste To Be Disposed Of (Waste Acceptance Requirements as of October 2010) - Konrad Repository - ", DRAFT, report SE-IB-29/08-REV-1, Bundesamt für Strahlenschutz (2010).

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8. "Wachstum. Bildung. Zusammenhalt. - Der Koalitionsvertrag zwischen CDU, CSU und FDP". http://www.cdu.de/portal2009/29145.htm

9. "Zutrittswässer und Laugen", BfS-ASSE II press release, May 12, 2009. http://www.endlager-asse.de/cln 135/DE/WasIst/Bergwerk/ZutrittswaesserLaugen.html