The repository

Regulations include guidelines on geologic conditions. Of special interest is the stabiUty of the geology against faulting, volcanic action, and earthquakes. The repository is to be located in an arid region, where the water table is quite low. The host rock is to have a suitable porosity and a low hydrauhc conductivity. 

Site characterization studies include a surface-based testing program, potential environmental impact, and societal aspects of the repository. Performance assessment considers both the engineered barriers and the geologic environment. Among features being studied are the normal water flow, some release of carbon-14, and abnormal events such as volcanic activity and human intmsion. The expected date for operation of the repository is 2013. 

Transuranic Waste. Transuranic wastes (TRU) contain significant amounts (>3,700 Bq/g (100 nCi/g)) of plutonium. These wastes have accumulated from nuclear weapons production at sites such as Rocky Flats, Colorado. Experimental test of TRU disposal is planned for the Waste Isolation Pilot Plant (WIPP) site near Carlsbad, New Mexico. The geologic medium is rock salt, which has the abiUty to flow under pressure around waste containers, thus sealing them from water. Studies center on the stabiUty of stmctures and effects of small amounts of water within the repository. 

The primary issue is to prevent groundwater from becoming radioactively contaminated. Thus, the property of concern of the long-lived radioactive species is their solubility in water. The long-lived actinides such as plutonium are metallic and insoluble even if water were to penetrate into the repository. Certain fission-product isotopes such as iodine-129 and technicium-99 are soluble, however, and therefore represent the principal although very low level hazard. Studies of Yucca Mountain, Nevada, tentatively chosen as the site for the spent fuel and high level waste repository, are underway (44). 

If the economics of recycling were improved, that option would become preferable for spent fuel because the permanent repository issues of the residual fission products would be simpler. The economic value of the energy generated from the recycled plutonium and uranium would substantially allay the costs of the repository as compared to the spent fuel throwaway option. 

It has been traditional to subject workers to higher risks than the public, (a) Write a short discussion of the equities of this practice with consideration for the fact the worker may leave employment that imposed a long term risk, (b) The Nevada Test Site has been selected as a possible location for a high level waste repository. For purposes of the risk assessment, the workers in the repository will be treated as workers with subsequent higher allowable risk. There are many other workers at NTS. Discuss whether these should be treated as workers or public, (c) If they are treated... 

Eukaryotic ceils possess a discrete, membrane-bounded nucleus, the repository of the cell s genetic material, which is distributed among a few or many chromosomes. During ceil division, equivalent copies of this genetic material must be passed to both daughter ceils through duplication and orderly partitioning of the chromosomes by the process known as mitosis. Like prokaryotic... 

Nucleus The nucleus is separated from the cytosol by a double membrane, the nuclear envelope. The DNA is complexed with basic proteins (histones) to form chromatin fibers, the material from which chromosomes are made. A distinct RNA-rich region, the nucleolus, is the site of ribosome assembly. The nucleus is the repository of genetic information encoded in DNA and organized into chromosomes. During mitosis, the chromosomes are replicated and transmitted to the daughter cells. The genetic information of DNA is transcribed into RNA in the nucleus and passes into the cytosol where it is translated into protein by ribosomes. 

In 1976 the Swedish government stipulated that no new nuclear reactors should be charged until it had been shown how the radioactive waste products could be taken care of in an "absolutely safe manner" (8). Consequently, the nuclear power industry (through their joint Nuclear Fuel Supply Co, SKBF) embarked on a program referred to as the Nuclear Fuel Safety (KBS) Project (8). In one of the schemes (9) a repository for spent nuclear fuel elements in envisaged at a depth of 500 m in granitic bedrock. The repository will ultimately contain 6000 tonnes of uranium and 45 tonnes of plutonium. The spent fuel elements will be stored in copper cylinders (0.8 m in diameter and 4.7 m in length) with a wall thickness of 200 mm the void will be filled with lead. 

The widespread use of many metals such as silver, cadmium, copper, mercury, nickel, lead, and zinc has resulted in their accumulation in the environment. Sediments are often the repositories of toxic metals (e.g.. Table 15-2). For example, copper is used as an anti-biofouling agent in marine paints and many harbor sediments contain markedly elevated levels of copper. 

EPA proposed standard in 4( X I R 191 (EPA. 1985). Releases of radionuclides from the repository were to be limited to amounts such that the projected number of premature cancer fatalities over a 10,000 year period would not exceed 1000, i.e. an average of one per decade.2 This target appeared to be attainable until it was... 

The spent firel issue is central to long-term fuel cycle policy, not simply because large volumes are threatening to clog the arteries of the nuclear power industry but because spent fuel is the repository of most of the worid s plutonium, some 1000 tons at present, and is already dispersed among the 30-odd countries in which nuclear power plants are located. The indefinite accumulation of these dispersed inventories has proliferation implications that are at least comparable in their gravity to the surplus weapons plutonium inventories in Russia... 

Of course, Crowley is positioning himself and his journal as the repository of the ancient knowledge. (The idea that Crowley was trustworthy must have rankled Golden Dawn members to no end.) But beyond the narcissism so characteristic of Crowley s writing, the efforts by which scientific illuminism attempted to blur the boundaries of science depended on the assertion that ancient occult knowledge could be used with modem scientific mles of experiment, verification, and accurate measurement because it in fact was an extension of the physical sciences. 

In adults, bone is the repository for 98% of the body s calcium and 85% of the body s phosphate in infants, the skeleton contains about 96% of the body s calcium and 70% of its phosphate. The Ca/P ratio Of bone mineral (hydroxyapatite or SECa PO Jj-CafOH can be expressed in various units yielding different values ... 

Yucca Mountain may be the most studied area in history. The federal government claims that the environmental effects of the repository will be small and have essentially no adverse impact on public health and safety. These claims have been challenged and there has not been the political will to go ahead with the site. 

For protein crystallography, the repository of most protein crystal structures is the PDB hosted at http // www.rcsb.org/pdb/ (Berman et al., 2000). This database contains the 3-D coordinates (and sometimes the structure factor files) for almost all protein crystal structures. Most journals currently require deposition of the coordinates when pubhshing stmcture papers. Each structure is given a unique identification code that will be listed in the paper (see Figure 22-1 for examples of PDB codes). Structures can be accessed using this code, or using various other search criteria. The PDB also contains structural information for NMR structures. 

If we create a repository and make it too bulky, the chances of getting useful information actually decrease with time. So, there is this trade-off. . . Also, we are implementing many shorter life-cycle projects nowadays - 6 weeks to 3 months duration. Suppose someone searches the repository, gets three documents, takes 2 to 3 days to read them and then finds that they are not useful. This is a considerable waste of time. If this happens, this person might question the very utility of the repository and decide not to use it in the future. 

DNA codes for its own synthesis at the time of cell division. Thus, DNA acts as the agent of inheritance. As is developed below, DNA is a double-stranded helical molecule—the famous double helix—in which the two strands are complementary. DNA is the repository of information that is expressed in synthesis of the proteins of the cell. Therefore, DNA acts as the determinant of the biochemical personality of the cell. ... 

DNA deoxyribonucleic acid. DNA is one of two forms of nucleic acids the repository of genetic information in most living organisms. 

It will be convenient to examine the underlying chemistry in terms of interactions of pairs of constituents of the repository and, finally, the waste-form stability itself ... 

The establishment of the groundwater composition by the rock and the backfill materials of the repository. 

Environmental Fate. It can be concluded from the transport characteristics that surface water sediment will be the repository for atmospheric and aquatic thorium. Normally, thorium compounds will not transport long distances in soil. They will persist in sediment and soil. There is a lack of data on the fate and transport of thorium and its compounds in air. Data regarding measured particulate size and deposition velocity (that determines gravitational settling rates), and knowledge of the chemical forms and the lifetime of the particles in air would be useful. 

Because of the multivalent nature of the actinide ions, understanding the radiation-induced change of the valence-state of the actinide in solutions under self-irradiation or external irradiation is a challenge in radiation chemistry. Some of the ions are strong a-emitters. It is also important from a practical viewpoint that the solution chemistry of actinide ions is closely related to the storage and the repository of the wastes. Much work combined with experiment and simulation has been conducted and reviews were summarized [136,140-144]. 

Seawater is invaded into the groundwater and thus groundwater sometimes contains sodium chloride, which is called the seawater-type one. One of the possible sites for the repository is a salt mine. It is assumed that the site does not receive water invasion for so long, and this indicates the stability of the site. If groundwater invade the site, saline solution would be irradiated. Thus understanding of the radiolysis of water containing NaCl is also taken into consideration after the corrosion of the overpack of the HLW. Chloride ion is one species... 

DNA Deoxyribonucleic acid is the repository of hereditary characteristics. The most commonly described form of DNA is the double-stranded form, arranged as a helix. Chromosomes are composed of double-stranded DNA. So called DNA fingerprinting offers a basis for evaluating the probability that blood, hair, semen or tissue samples originate from a given person, and thus offers a forensic tool as well as a means to determine lineages of humans and animals... 

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