Discovery of radioactivity made by Antoine Henri Becquerel in 1896 has become a significant achievement. Up till now the radioactive materials are put to good effect in medicine, agriculture, heavy industry, electricity generation etc. However, despite the wide range of radioactivity applications in useful purposes, there is an opposite side to this discovery, that is, abusing ionising radiation may lead to burns, radiation sickness, and death, emergence of cancer, tumours, and genetic mutations. Ionising radiation source (IRS) is a physical object, except nuclear installations, containing a radioactive substance, or a technological device, which creates, or, under certain conditions, may create the ionising radiation. In order to ensure compliance with the allowable limits of radiation effects to personnel, public and environment, established by rules, regulations and standards on safety, there is a State regulatory control.
The radioactive sources, which are not under regulatory control, or have never been regulated, or were left without attendance, lost, placed in inappropriate location, transferred without proper permission from the State or stolen are called the “orphan sources”.
”Orphan sources” means such IRS that are not covered by the State regulatory control due to the fact that they have never been under regulatory control, or because they were left, lost, placed inappropriately, stolen or transferred without proper formal permission.
The problem with “orphan sources” lies in their potential hazard to public health and difficulty in their detection. Ionising radiation sources are normally stored in metal containers with thick walls, which, using the corresponding equipment, makes it difficult to identify the presence of a radioactive source inside. Moreover, they could be objects of various sizes and shapes, and, as a result, they are often become the items of interest for diverse population groups with a variety of purposes.
An “orphan source” falling into the hands of a regular citizen may lead to catastrophic consequences. An example of such situation may be the case of radioactive contamination occurred in 1987 in the town of Goiania, Brazil. A component of the radiotherapy unit containing the radioisotope Caesium-137, was put on the scrapheap by perpetrators after the robbery. After that, this source was found by a local citizen, whose mishandling with it had led to the spread of radioactive contamination, and, consequently, four people had died with radioactive contamination, while the area where this source was located would be unsuitable for life for the coming 300 years.
Prevention of the “orphan sources” emerging
With the account taken of the abovementioned information, it is obvious that there is a necessity of preventing the “orphan sources” from emerging. Ones of the basic preventive measures are:
- Ensure a permissive principle of the use of sources (i.e. a radioactive source may only be used by individuals or enterprises who have proved to the State that they are capable of ensuring safety and security of the source),
- Accountancy and control of radioactive sources.
Therefore, the use of nuclear installations and ionising radiation sources in Ukraine is based on a permissive principle. The State Nuclear Regulatory Inspectorate of Ukraine has the authority of issuing permits for each individual type of activity related to the use of radioactive material, in particular, a license for using an ionising radiation source (IRS).
According to the Law of Ukraine ”On licensing activity in the area of nuclear energy utilisation”, the State registration of sources of ionising radiation is mandatory, and, therefore, accountancy and control of location and movements of the sources are ensured. According to information voiced at the International Seminar “Orphan and vulnerable sources regulation. Experience and prospects of Ukraine”, held at the end of 2012 in Kiev, as of December 2012, the State IRS Register, where all the sources and operations with them are filed, has 12462 radioactive sources and 15838 generating devices registered. It should be noted, that according to the Provisions on the State Ionising Radiation Sources Register and the procedure of payment for services on their registration approved by theResolution of the Cabinet of Ministers of Ukraine of 4 August, 1997, No. 847, the State IRS Register is the sole State system for accountancy and control of ionising radiation sources, the handling of which is not exempted from regulatory control and which manufactured on the territory of Ukraine or those sources brought in or took out through the State border, as well as the owners of these IRS, legal entities or individuals for whom IRS are formalised on the basis of the right of economic management or control, or being in their possession and use on other grounds. Significantly, among some 500 thousand ionising radiation sources in Ukraine, more than 450 thousand pieces have already been decommissioned and are now stored at the State facilities for radioactive waste management and accounted for in the State Radwaste Register.
In such a manner, since the fully functional system of the State regulation, including accountancy and control of the sources, has been established, a potential occurrence of orphan IRS is minimised.
Another preventive method is counteracting potential threat of IRS converted into the “orphan” category. The sources that may be abandoned are categorised as vulnerable. According to information presented at the International Seminar “Orphan and vulnerable sources regulation Experience and prospects of Ukraine”, held at the end of 2012 in Kiev, vulnerable sources are the radioactive sources, which presently are under control, but this control is not sufficient for ensuring continuous safety and security. In the first instance, it is those sources, which are no longer in use or of no use for the enterprises. The regulatory authority of Ukraine limits the terms of storage of such sources and requires that they be transferred to the specialised facilities, where such spent sources are provided with high level safety and security.
A particular hazard comes from those sources, which have been in ownership of enterprises that went bankrupt or that are financially instable, therefore, individually unable to handle the issue of transferring such sources to the specialised facilities. In order to resolve this issue there are international programmes underway with American and German partners. These programmes aimed at collecting the sources from sites and moving them safely to the specialised facilities. In the outcome, the substantial results have been achieved in implementing these programmes, and large numbers of sources have been collected.
However, there is a certain number of sources beyond regulatory control. One of the causes of such situation is that there were no mandatory requirements to control certain ionising radiation sources in the past when the less stringent requirements were established for control of certain types of sources. As of today, such approach has been changed radically, and the sources, which were outside regulatory control, are now subject to mandatory registration or licensing. Another cause is the loss of control over certain IRS due to the following reasons:
a. the source was lost;
b. the source was stolen;
c. the source was located in inappropriate place
Such sources have to be detected (searched for).
Orphan radioactive sources
Searching for “orphan” sources
The issue of searching for “orphan” IRS is bulk large in Ukraine. Ukraine has two methods of searching for already “orphan” sources: administrative and physical.
The search for “orphan” IRS requires a systematic approach. In this context, theadministrative method plays an important role. Its application envisages the search for information on the “orphan” sources, as well as holding inquiries that allows collecting the necessary information at the initial phase of building the system of detecting the “orphan” sources for its efficient functioning.
In Ukraine this method is not considered effective since historically the process of regulating the “orphan” sources in this country have been running on the regular basis, which made it practically impossible to loose information on locations of the discussed sources.
Therefore, in Ukraine more attention is paid to the physical search i.e. search for the sources by their physical characteristics: external appearance and radiation. This type of search takes a special place on the road to resolving the issues with “orphan” sources, since IRS are normally held in metal containers, they are often found in scrap metal. Moreover, there is a high probability of their consequent remelting, which may lead to a considerable radioactive contamination. Thus, it is this type of search that is more effective.
There are passive and active systems for the search of “orphan” IRS within the frame of physical search. The difference between these two systems is that thepassive system envisages the search by installing radiation portal monitors in all the key points, such as: customs, ports, scrap metal management facilities, especially Iron & Steel Works, and border checkpoints. While the system of activesearch envisages the direct rummage of all suspicious sites with portable radiation monitors, and, at the same time, the additional methods could be applied, such as gamma aerial survey and vehicle gamma radiation survey. Regrettably, the active search requires a lot of expenditures, which Ukraine is unable to cover individually; therefore, the need arises to involve the international assistance. Due to economic problems worldwide it is difficult to obtain financial support, which hampers the active development of this system in Ukraine. Nevertheless, there is willingness in Ukraine to make the active search more effective, and it is planned to commence this process with inspecting the sites, which were used by the military and signed away for public use. Additionally, in order to achieve the desired goal, the SONNI new mobile radiological laboratory, equipped with gamma-detector, will be used in Ukraine.
It should be noted, that according to the conclusion of the “Green book” (consultancy in IRS safety in Ukraine of 01/03/2008) the active search is the most effective method of “major “cleanup” of the country’s territory” from the “orphan” IRS since the system of passive search works only if an “orphan” source reaches the point of passive control, but in case there is no movement, a source could only be detected through the active search.
Nevertheless, in this context, the important fact is that the passive search in Ukraine is represented by a multi-barrier system of control, which includes:
- Radiation monitors and other means of radiation monitoring existing on the borders.
- Radiation monitoring at enterprises. Currently, there is a tendency of growing number of detected sources, which were not accounted for earlier during the annual IRS inventory (performing the annual inventories is a regulatory requirement).
- Radiation monitoring at scrap-yards. Today it is hard to say, to which extent this barrier may be considered effective, since there is no substantial activity observed in detecting the orphan sources by such facilities. The causes for this may be the following: the orphan sources really have not come into their view, or the enterprises chose not to accept the scrap metal from vehicles the background radiation of which exceeded the normal limits. According to the Resolution of the Cabinet of Ministers of Ukraine of 2 June, 2003, No. 813 , in case of detection of radioactive material in the course of border control, or environmental or radiation monitoring, financial liability for expenses, related to radioactive materials being in illicit trafficking, shall rest with the owner (user) of cargo, while in case of absence of the owner, the responsibility shall be placed upon the local power authorities. Unfortunately, the situation is being shaped up in a way so that local government authorities are often unable to tackle the discussed difficulties; therefore, in the long run an enterprise is forced to pay for disposal of a source. Such situation may provoke the latters to refuse accepting the cargo, which background radiation exceeds the normal limits, so that to avoid additional financial expenses. In the international practices there is an example of resolving such a dilemma – the Spanish protocol on cooperation in the area of radiological surveillance of the metallic products (ECE / TRANS / AC .10/2006/2). According to this document, a metal processing enterprise shall be exempted from payment for handling the detected “orphan” sources on the account of minor annual payments to the corresponding fund.
- Radiation monitoring at iron and steel enterprises. According to the Order No. 183 of 18 November, 2011, No. 1321/20059 on approval of Licensing conditions for carrying out business activities on provision, processing, metallurgical processing of scrap metal of ferrous and non-ferrous metals, the experts of an enterprise shall ensure checking against explosion safety and obligatorily perform radiation monitoring of the scrap metal. However, despite of this, the iron and steel enterprises install portal monitors totally on a volunteer basis and perform monitoring as they do realise the hazards and material damage that could be inflicted by decontamination of all the equipment in case of radioactive contamination. Such barter trade is very effective.
- Additional radiation monitoring of the scrap metal that is exported.
To summarise, it is worth mentioning that it is necessary to apply maximum effort, so that after all existing vulnerable and “orphan” sources have been collected, it would be possible to minimise the probable occurrence of new vulnerable or orphan radioactive sources. To this end, there are the State regulatory requirements, which must be complied with.
Requirements for the existing spent (vulnerable) sources:
The Ukrainian nuclear regulatory authority applies stringent enough requirements to the enterprises handling IRS: not to store the spent sources for longer than 6 months. If an enterprise fails to comply with this requirement, it may be penalised with the corresponding sanctions. If such sources have been converted into the radioactive waste category, the enterprises would then have to make the corresponding payments to the radwaste management fund. Experience has proven that it is unprofitable for the enterprises to keep such sources due to several factors: one the one hand, there is a pressure from the side of inspectors, who may issue fines in case the requirements are not complied with, on the other hand, there is an obligatory payments to the radwaste management fund should these sources are re-categorised as the radioactive waste.
Requirements to the newly purchased sources:
In this context there are two options for the enterprises purchasing a new source:
- Pay to the radwaste management fund straightaway; while, upon expiry of the source’s service life, a specialised department will individually and free of charge take this source away for disposal.
- Conclude an agreement with the supplier on its obligation to take the source back after it has been used.
Today Ukraine is implementing the best international practices in the area of “orphan” sources management. At the same time, it is important to understand that a large number of the found sources is not a reflection of the fact that the system of control is ineffective, quite the opposite, it is because there is an effective search system in place. Moreover, Ukraine reports to the IAEA of each and every found source, the country has chosen straightforward and transparent policy in the issue: we always report when we find and make our results available. Therefore, it is possible to minimise the problem, it is also possible to ensure control, but it is not possible to fully prevent the occurrence of vulnerable and orphan sources, that it is why it is required to have an efficient system for the effective response.
Moreover, it should be emphasised, that illicit possession of a source is very unprofitable. Selling it for big money is a myth. If found guilty, a sentence may be of up to 8 years in prison.