Production of nuclear weapons

The neutrons in a research reactor can be used for many types of scientific studies, including basic physics, radiological effects, fundamental biology, analysis of trace elements, material damage, and treatment of disease. Neutrons can also be dedicated to the production of nuclear weapons materials such as plutonium-239 from uranium-238 and tritium, H, from lithium-6. Alternatively, neutrons can be used to produce radioisotopes for medical diagnosis and treatment, for gamma irradiation sources, or for heat energy sources in space. 

A new area of research concerns exposure assessment for beryllium in the production of nuclear weapons at nuclear defense industries. A safe level of exposure to beryllium is still unknown. Potential explanations include (1) the current exposure standard may not be protective enough to prevent sensitization, or (2) past exposure surveillance may have underestimated the actual exposure level because of a lack of understanding of the complexity of beryllium exposures. Task-based exposure assessment provides information not directly available through conventional sampling. It directly links exposure to specific activity associated with contaminant generation and provides in-depth evaluation of the worker s role in a specific task. In-depth task analysis is being used to examine physical, postural, and cognitive demands of various tasks. 

In 1999, the SGS was used at the U.S. Department of Energy s (DOE s) Los Alamos National Laboratory (LANL) in Los Alamos, New Mexico, to sort 2526 yd of soil and debris contaminated with up to 431.46 picocuries per gram (pCi/g) of uranium from the production of nuclear weapons. The actual cost for the operation was 275,745. This figure included 6600 for predeployment activities, 46,000 for mobilization, 185,445 for processing, 35,000 for demobilization, and 2700 for the final report. LANL incurred 543,400 in additional costs for staff, the prime contractor, recharges, and soil disposal. The overall nnit cost was 109/yd of soil processed (D21040S, p. 70 D21230W, pp. 13, 14). 

Transuranic Waste Transuranic waste (TRU) results from fuel reprocessing and fuel fabrication facilities, the production of nuclear weapons, and the decommissioning of nuclear reactors or fuel cycle facilities. TRU includes clothing,... 

Radioactive contamination as some background radiation from natural sources, such as radon, occurs in some regions of the world, but there is particular concern over the contamination of surface water and groundwater by radioactive compounds generated by the production of nuclear weapons and by the processing of nuclear fuel. Many of these areas have remained unrecognized because of government secrecy. 

Pii (about 2.2 kg), -" Pu (about 1.1 kg) and " Pu (about 0.4 kg) are generated by (n, y) reactions from Pii. Pu is a valuable nuclear fuel and may also be used for production of nuclear weapons. The global production rate of Pu in nuclear power reactors is of the order of 100 tons per year contained in spent fuel elements. Non-proliferation agreements should prevent uncontrolled distribution of Pu. Moreover, Pu is highly toxic. Am and Cm arc generated in smaller amounts in nuclear reactors by (n, /) reactions (about 0.15 kg Am and about 0.07 kg Cm per ton of spent fuel after a burn-up of 35 000 MW d per ton). 

High-level wastes are a different matter. After a period of time, the fuel rods in a reactor are no longer able to sustain a chain reaction and must be removed. These rods are still highly radioactive, however, and present a serious threat to human life and the environment that can be expected to last for tens of thousands of years. These rods and any materials derived from them (as, for example, during chemical dismantling of the rods to extract their plutonium for the production of nuclear weapons or for use as a nuclear fuel), are considered high-level wastes. 

Plutonium represents a dual challenge because it is a valuable energy source and a matter of global concern because of its potential health hazards and possible use for the production of nuclear weapons. 

Oi (1998) points out the problem, which is what to do with plutonium either in a separated form or contained in spent fuel. A number of issues arise because of plutonium s potential use as an energy source and for the production of nuclear weapons. 

Fluorine is combined either directly or indirectly with other elements to form compounds such as hydrofluoric acid, fluoropolymers and is used in the synthesis of organic fluorine compounds such as fluorides as in the manufacture of Freon (i.e., dichlo-rodifluoromethane, CCI2F2), which is used as a refrigerant. Fluorine is used in the manufacture of uranium hexafluoride that is necessary for the separation of the isotopes of uranium in centrifuges in the production of nuclear weapons. Fluorine and its compounds are used in producing more than 100... 

Computational molecular science is a key technology for addressing the complex environmental cleanup problems facing the Department of Energy s nuclear production sites as well as other polluted sites in the nation. Production of nuclear weapons at U.S. DOE facilities across the nation over four decades has resulted in... 

In Germany in 1938, Otto Hahn and Fritz Strassmann, skeptical of claims by Enrico Fermi and Irene Johot-Curie that bombardment of uranium by neutrons produced new so-called transuranic elements (elements beyond uranium), repeated these experiments and chemically isolated a radioactive isotope of barium. Unable to interpret these findings, Hahn asked Lise Meitner, a physicist and former colleague, to propose an explanation for his observations. Meitner and her nephew, Otto Frisch, showed that it was possible for the uranium nucleus to be spfit into two smaller nuclei by the neutrons, a process that they termed fission. The discovery of nuclear fission eventually led to the development of nuclear weapons and, after World War II, the advent of nuclear power to generate electricity. Nuclear chemists were involved in the chemical purification of plutonium obtained from uranium targets that had been irradiated in reactors. They also developed chemical separation techniques to isolate radioactive isotopes for industrial and medical uses from the fission products wastes associated with plutonium production for weapons. Today, many of these same chemical separation techniques are being used by nuclear chemists to clean up radioactive wastes resulting from the fifty-year production of nuclear weapons and to treat wastes derived from the production of nuclear power. 

The design and production of nuclear weapons today is a far simpler proccs.s than it was during the Manhattan Project. 

The acquisition of fissile material in sufficient quantity is the most formidable obstacle to the production of nuclear weapons. 

Cs Radioactive isotope of cesium with a30.2yearhalf-lifeproduced as a fission product of nuclear weapons explosions or in nuclear reactors. 

This by-product of nuclear-weapon testing may do more genetic and somatic damage than has been supposed. 

The major anthropogenic sources that have lead, or could potentially contribute, to the radionuclide contamination of the environment are the following (1) the testing and production of nuclear weapons (2) the normal activities of the nuclear power fuel cycle (3) the radioisotope production and research reactors and (4) the nuclear accidents. 

Radionuclides released from the production of nuclear weapon materials and from fabrication plants are not widely published. The exposures from nuclear materials production/ processing centers (Chelyabinsk, Krasnoyarsk, and Tomsk) in the Russian Federation were published, and the annual effective doses were 0.0054-0.11 mSv. 

In fast reactors, the uranium-plutonium fuel of equilibrium composition is unfit for production of nuclear weapons. Its breeding properties are worse than those of uranium 20% enriched in (the IAEA limit). Absence of plutonium and uranium separation in all stages of the fuel cycle guarantees proliferation resistance. 

Impacts are not limited to human health, as the physical environment is also affected by nuclear weapons production. From 1945 to 1990, the United States produced approximately 70,000 nuclear weapons other nations produced many additional nuclear weapons. Production of nuclear weapons has led to major environmental contamination. For example, the area around Chelyabinsk in Russia has been heavily contaminated with radioactive materials from the nuclear-weapons production facility in that area. The level of ambient radiation in and near the Techa... 

For many years from the 1940s, virtually all of the uranium that was mined was used in the production of nuclear weapons, but this ceased to be the case in the 1970s. Today the only substantial use for uranium is as fuel in nuclear reactors, mostly for electricity generation. Uranium-235 is the only naturally occurring material that can sustain a fission chain reaction, releasing large amounts of energy. 

ERDA was left with the mission of production of nuclear weapons and other nuclear missions. ERDA still had a promotion and regulation responsibility for the nuclear facilities that they owned. In 1977, ERDA was incorporated into the U.S. Department of Energy (U.S. DOE). The U.S. DOE was formed in response to the 1973 energy crisis. 

ERDA was responsible for the management of development and production of nuclear weapons, promotion of nuclear power, and other energy-related work, the production, utilization, and research facilities and to also develop and enforce safety requirements. ERDA and NRC lost their exemption from the Civil Services Program. 

The reprocessing involves separating the fission products from the actinides, and then separating the plntoninm from the uranium. The best known procedure of this type is the PUREX (Plutonium, URanium Extraction) process that is used for recovery of uranium and plutonium from irradiated fuel (see details in Chapter 2). The separated plutonium can be used for the production of nuclear weapons or converted into the oxide form, mixed with nraninm oxide and can be used as MOX nuclear fuel. 

This section of the paper deals with the issue of environmental clean-up and the release of land areas from regulatory control. Of particular interest in the context of this Seminar are areas which have become contaminated as a result of operations in the nuclear fuel cycle and which have to be decontaminated as part of decommissioning. Land areas may also become contaminated as a result of accidents in the nuclear fuel cycle, nuclear weapons testing, the production of nuclear weapons, and previous poor practices inside and outside the nuclear fuel cycle. An issue for consideration is whether all types of contamination situation should receive the same regulatory treatment. 

U will only be possible through isotope separation techniques. The high Pu to Pu ratio and the production of gamma emitting Tl in the thorium cycle are hindrances to nuclear proliferation. Pu has a spontaneous fission that contributes to increased residual heat of spent fuel that will complicate the production of nuclear weapons. 

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