IAEA Estimates of Global Inventories of Radioactive Waste

Original Link for  full text download http://www-pub.iaea.org/MTCD/publications/PDF/te_1591_web.pdf

Selected short quotes:

 

“It was considered worthwhile to produce a set of worldwide data that could be assessed to evaluate the legacy of the nuclear activities performed up to the transition between the twentieth and the twenty first century.

The assessment tries to cover the inventory of all the human produced radioactive material that can be considered to result from both military and civilian applications. This has caused remarkable difficulties since much of the data, particularly relating to military programmes, are not readily available. Consequently the data on the inventory of radioactive material should be considered as order-of-magnitude approximations. This report as a whole should be considered as a first iteration in a continuing process of updating and upgrading.

The accumulations of radioactive materials can be considered a burden for human society, both at present and in the future, since they require continuing monitoring and control. Knowing the amounts and types of such radioactive inventories can help in the assessment of the relative burdens. Knowledge of the national or regional radioactive waste inventory is necessary for planning management operations, including the sizing and design of conditioning, storage and disposal facilities. A global inventory, either of radioactive waste or of other environmental accumulations of radioactive material, could be used to provide a perspective on the requirements and burdens associated with their management, by means of comparisons with the burdens caused by other types of waste or other environmental threats.

The IAEA officer responsible for this publication was K. Hioki of the Division of Radiation, Transport and Waste Safety.”

“The production of electricity by nuclear means has created radioactive residues which have to be carefully managed and accounted for because they are potentially hazardous to human health. Similar residues have been generated as a result of the defence programmes in several countries. The residues include solid and liquid radioactive waste from civilian nuclear power production and from the production of nuclear weapons and residues from the above surface or underground testing of nuclear weapons.”

“In most countries, high level solid radioactive waste that is the product of solidification of the liquid waste generated by the first extraction cycle in the reprocessing of spent fuel, including spent fuel that is declared to be waste, is currently being stored in purpose-built stores pending disposal deep underground. In many countries, some lower activity waste containing mainly comparatively short lived radionuclides is being disposed of in near surface repositories. Liquid radioactive waste is generally converted to a solid form suitable for disposal, but there are some exceptions.

In some cases, mainly in the past, some liquid radioactive waste, considered too active for environmental dispersal, in the absence of safer management solutions has been pumped underground within enclosed aquifers or mixed with cement and injected as sludge in a low- permeability formation. Cases exist where high level waste (HLW) and higher activity low and intermediate level waste (LILW) in liquid form have been stored in near surface underground tanks and, after some decades, are still being kept in that form.

Gaseous and liquid waste containing very low levels of radionuclides are discharged to the environment in the same way as other low level industrial pollutants. This practice is subject to close regulatory control and environmental monitoring to ensure that the hazards to the public are minimal.

Finally there are sites, either above or below the ground, used in the past for either nuclear weapon testing or other purposes, or with significant amounts of radioactive materials, , that are considered to require continuing surveillance and monitoring to control access to the radioactive material.”

“Accumulations of radioactive material can be considered a burden for human society, both at present and in the future, since they require some level of continuing control. Knowing the amounts and types of such radioactive inventories can help in the assessment of the relative burdens. Knowledge of the national or regional radioactive waste inventory is necessary for the planning of management operations, including the sizing and design of processing, storage and disposal facilities. A global inventory, of radioactive waste and other environmental accumulations of radioactive material, could be used to provide a perspective on the requirements associated with their management, by means of comparisons with other types of waste or other environmental threats.”

“In the past, reliable information on the radioactive waste production of military or defence programmes has been rather difficult to obtain. This difficulty may continue in the future; for example, military waste is not included within the scope of the Joint Convention. In some countries, defence waste is not even subject to the normal controls of the national regulatory authorities or may be mixed with the waste from civilian uses.

Information on other environmental accumulations of radioactive material, such as those at nuclear test sites and locations of past disposal operations of liquid waste, is also not always complete.

It is evident that, globally, information on radioactive waste and on other radioactive residues in the environment is not complete. For this reason an estimation approach has been adopted in this report, which intends to provide an approximate but comprehensive assessment of the global inventory of radioactive waste and other human generated accumulations of radioactive material in the environment. The inventory derived in this publication should be considered the result of a first iteration. More reliable estimates may become available in the coming years as a result of progress within the various international data collection mechanisms.”

“The amounts of mine and mill tailings accumulated worldwide are not known in detail, since this information is not reported by all Member States in a consistent and reliable way. However, estimates of the inventory of uranium mining and milling waste can be produced from consideration of the data on global uranium production. No equivalent data on thorium production are available, but the extraction of thorium has been relatively small in comparison with uranium. An additional uncertainty associated with such estimates is due to the fact that average uranium concentrations in mined ores has to be used to calculate the inventory of both mine and mill tailings. Since these values are not always available, the resulting average concentrations used to derive the amounts of tailings from the reported amounts of produced uranium are necessarily uncertain. Further, the values are distorted by the fact that early use of uranium in the US was largely with imported ores of higher quality. Additionally, the greater use of in situ leaching techniques has reduced the production of tailings. Finally, new mining techniques including the freeze drill system and the mining of higher grade ores has resulted in smaller mill tailings production [6]. The utilization of down-blended enriched weapons uranium and the use of mixed weapons plutonium and natural uranium has further complicated the picture. The vagaries of the uranium market including price changes has also influenced the amount of uranium mined. Therefore, estimations of future production are very uncertain.

The total amount of uranium produced worldwide up to the year 2004, is approximately 2.2 million tonnes2 [6].”

“In the late 1990s, there were two uranium mines operating in Australia: Ranger in the Northern Territory and Olympic Dam in South Australia. Together they generated about 3 million tonnes per year of tailings, containing about 70% of the radioactivity originally present in the ore – including almost all of the 230Th and 226Ra. The total quantity of tailings accumulated in Australia at that time was about 50 million tonnes, resulting from a total uranium production of about 70 000 tonnes.

In the United States of America, the accumulation of commercial mill tailings, generated up to the end of 1996, amounts to about 190 million tonnes with a volume of about 120 million m3 [7]. To estimate the accumulation of uranium mine and mill tailings generated by defence activities in the USA, a possible approach is to apply the estimated production of tailings per warhead to the total number of warheads produced in the country. Using the published estimates of 2000 tonnes of both mine and mill tailings for single warhead and 17 000 as the total number of warheads produced, about 34 million tonnes each of mine and mill tailing can be assumed to have been generated by defence programmes 3 [8]. Adding this amount to the estimated production of commercial mill tailings gives a total close to 220 million tonnes. Accepting the assumption used in [8], that mine tailings amounts are roughly the same as mill tailings, it is possible to estimate that about 220 million tonnes of mine residues exist in proximity to the mines.

“In addition to the waste generated by the nuclear fuel cycle front-end activities discussed in the preceding section, nuclear power generation causes the production of several kinds of radioactive waste, including spent reactor fuel (if it is declared waste), high level waste (HLW) that is generated mainly from the chemical reprocessing of spent fuel and low and intermediate level waste (LILW) that is generated as a result of reactor operations, reprocessing, decontamination, decommissioning and other fuel cycle activities.

“CONCLUSIONS
The purpose of this publication is to produce global estimates of the amounts of residual radioactive material accumulated by nuclear activities up to the beginning of the 2000s and requiring continuing institutional controls. Despite the great progress achieved in many areas, particularly thank to the NEWMDB, some information is still open to question, since not all Member States have provided the required waste inventories. An additional uncertainty, due to the differences among classification systems used by various Member States has been also addressed by the NEWMDB by means of a matrix tool to normalize information submitted under a variety of classification systems. A number of promising activities aimed at improving the situation are currently going on at the international level [29, 30].
Official information about radioactivity in contaminated sites as a result of accidents or weapon testing is even more incomplete. As a result it was felt that exploring alternative approaches aimed at produced global estimates of the radioactive waste inventory and of radioactive material present in the environment was a worthwhile exercise.
The resulting estimates, which are based on broad simplifications, are characterised by unavoidable uncertainty. However, considering that they are not to be used for design purposes, for example for planning management activities, but simply to produce an order-of- magnitude assessment of the societal burden generated by nuclear activities, the exercise may help to place in a rational perspective the radiological and environmental burden generated by the first half century of nuclear activities. The estimates may be used for comparison with environmental burdens created by other means of energy production and other human activities and to provide some rationality to the societal controversy about nuclear energy.
This publication has to be considered as a first iteration to be revised and updated in the future as more reliable and comprehensive data become available.”

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