 Upon Iran's announcement that it had successfully enriched uranium for nuclear fuel, the United States spoke in condemnation of that country and its nuclear efforts. The United States maintained that Iran once again has taken the pathway of defiance in the international community. On the other hand, Iranian President Mahmoud Ahmadinejad confirmed Tuesday his country has successfully produced enriched uranium at a low grade level sufficient to power nuclear plants. He stressed that the enrichment activities were for peaceful efforts only and that no country should stand in Iran's way of the peaceful development of nuclear energy. He stated that Iran is a peaceful nation. He also noted that Iran's nuclear activities are being closely watched by the International Atomic Energy Agency.
Medical radioactive waste:
Sources of beta and gamma rays prevail in radioactive medical waste. This waste is divided into two main classes. Short-lived gamma radiators such as technetium (99Tc) are used in diagnostic nuclear medicine. The majority of these substances disintegrate within a short time after which they can be salvaged as regular garbage. Examples of other isotopes, which are used in medicine (the half-decay period is mentioned in parentheses):
Yttrium (90Y) is used for treating lymphocyte (2.7 Days);
Iodine (131I), diagnostics of thyroid, treating thyroid cancer (8 days);
Strontium (89Sr), treatment of bone cancer, internal infections (52 days);
Iridium (192Ir), brachytherapy (74 days);
Cobalt (60Co), brachytherapy, external radiation therapy (5.3 years);
Caesium (137Cs), brachytherapy, external radiation therapy (30 years)
Industrial radioactive waste:
Industrial radioactive waste can contain sources of alpha, beta, neutron or gamma rays. Gamma radiators are used in radiography; sources of neutron radiation are used in various branches, for example, during the radiometry of oil wells.
The issue about the widespread presence of nuclear weapons:
While working with uranium and plutonium, the possibility of their use is often considered for the creation of nuclear weapon. Active nuclear reactors and nuclear arsenals are carefully protected. However, highly active radioactive waste from nuclear reactors can contain plutonium. It is identical to plutonium, used in reactors and consists of 239Pu (ideally suited for the creation of nuclear weapons) and 240Pu (an undesirable component, which is extremely radioactive); It is very difficult to disintegrate these two isotopes. Moreover, highly active radioactive waste from reactors is full of highly radioactive fission products; however, the major part of fission products is the short-lived isotopes. It indicates, it is possible to bury the waste and fission products disintegrate after several years thus reducing the radioactivity of the waste and facilitating to work with plutonium. Moreover, the undesirable isotope 240Pu disintegrates faster than 239Pu, thus, the quality of raw materials for the creation of weapon increases in due course (despite the reduction in quantity). It leads to disputes that eventually the storing places of waste can turn into original “plutonium mines”, from which it would be rather easy to extract raw materials for the creation of weapon. The fact that the half-life period of 240Pu constitutes 6560 years works against these assumptions and the half-life period of 239Pu — 24110, thus, the comparative concentration of one isotope with respect to other takes place only after 9000 years (it means, that during this time, the percentage of 240Pu in the substance, consisting of several isotopes, will on its own decrease by two times - the typical transformation of reactor plutonium in plutonium weapons). Therefore, “mines of plutonium for weapons” become a problem in the very distant future; so, sufficient time is available to resolve this issue with the help of modern technologies before it becomes urgent.
One of the solutions for this problem is to reuse the treated plutonium as fuel, for example, in fast nuclear reactors. However, the existence of plants for the regeneration of nuclear fuel, necessary for separating plutonium from other elements, creates a possibility for the distribution of nuclear weapons. In pyrometallurgical fast reactors, the waste has a actinoid structure, which does not allow it to be used for weapons creation. |
