Radioactively contaminated land

Baes CF, Garten CT, Taylor FG, et al. 1986. Long-term environmental problems of radioactively contaminated land. Environ Int 12 543-553. 

CHARACTERISATION OF RADIOACTIVELY CONTAMINATED LAND AT DOUNREAY, AN AREA WITH A HIGH NATURAL BACKGROUND... 

It is also possible to make measurements in situ, for example portable gamma detection equipment can be used if the target radionuclides can be characterised by key-line gamma energy levels. Considerations of the specimen size leads to an important difference between in situ investigations of chemically contaminated land and radioactively contaminated land. It is possible to make field measurements in situ of the chemical concentration of metals in soil by using Portable X-Ray Fluorescence (PXRF) equipment. In PXRF, the specimen size is of the order of a few cubic millimetres. It is therefore much smaller than a typical specimen that would be extracted for laboratory analysis. ... 

The Shallow land Burial ofEow-Eevel Radioactively Contaminated Solid Waste, Committee on Radioactive Waste Management, National Academy of Sciences, Washiagton, D.C., 1976. 

National Academy of Sciences, "The shallow land burial of low-level radioactively contaminated solid waste", 2101 Constitution Ave., N.W., Washington, D.C. 20418, 150, 1976. 

Despite these qualifications, vitrification has some advantages. The vitreous mass is chemically inert and has durable physical properties that lock up contaminants effectively. This is a key advantage when dealing with radioactive contaminants (White et al., 1996). Under some circumstances, the glassy mass can be reused, and some of the energy costs may be recuperated. If the vitrified mass is to be land-filled, the reduction in waste volume is an added cost-saving benefit, in addition to the very inert condition of the glassy material. 

According to Baeza et al. (1994), the radioactive contamination of sea and land in the Antarctic regions derives from the fallout of atmospheric atomic explosions executed since 1945, apart from emissions made by nuclear and radioactive facilities. The authors examined samples of U. antartica collected near the Spanish Antarctic Base, Juan Carlos I, situated on Livingston Island in the South Shetland archipelago in... 

As we saw in Chapter 11, one major drawback to most of the radioactive elements discovered and produced in greater than the extremely small amounts found in nature is that they accumulate in the environment. Land, water, and air are affected by radioactive contamination. Depending on the wind or water flow, radioactive levels remain in place or are spread over a wide region. Different elements have very different decay rates. 

The production of nuclear weq)ons in the United States has required a vast array of facilities, including mines, laboratories, nuclear reactors, chemical plants, machine shops, and test sites. Our weapons production conq)lex has manufactured tens of thousands of warheads over the past 50 years, resulting in radioactive contamination in thousands of buildings, soils, surface water and groundwater. The production complex, including sites in 33 of our states and Puerto Rico, totals 10.8 million square meters of buildings and 9,360 square kilometers of land (or 936,000 hectares)- a total area about one-third the size of Belgium. 

A large amount of radioactivity was released from the Fukushima accidents, but a lot of the radioactivity drifted out to sea. The area of seriously contaminated land was much less than for Chernobyl - probably less than one-tenth (Fig. 15.7). 

The values of activity concentration provided in this Safety Guide are not intended to be applied to the control of radioactive discharges of liquid and airborne effluents from authorized practices, or to radioactive residues in the environment. Guidance on the authorization of discharges of liquid and airborne effluents and the reuse of contaminated land is provided in Refs [9, 10],... 

Cement is used in a variety of applications in which it comes into contact with the geological environment. In hydrocarbon well-bores and mine-shafts it is a principal component of the engineered environment adjacent to the host geology. In many radioactive waste (or rad-waste ) concepts and some landfill and contaminated land sites, cementitious material forms part of the system of barriers between waste and the biosphere. Its barrier properties include high sorption capacity, potentially low permeability, and the ability to condition its porewaters to a highly alkaline pH. This is particularly important around radwaste repositories where high pH lowers the solubility of a number of the key radionuclides and also slows the corrosion of the metal canisters in which the waste may be placed. 

Cesium, strontium and plutonium have been detected in sediments of Ob and Enisey downstream as far as the mouths of the rivers and in Enisey floodlands. In some places contamination was higher than that from global fallout. Although nuclear military facilities in Siberia could be potential contributors to the radioactive contamination of the Arctic, global fallout onto the land seems predominant. Some part of radionuclides is washed into the rivers and ultimately transported to the Kara Sea. As the catchment area of the river Enisey is smaller than that of Ob , its contribution into the radioactive contmnination of the Arctic would be smaller [OTA, p. 45]. Potential contributions of the weapons complex to Arctic pollution depends on many factors, and permanent monitoring of the weapons production sites is necessary. 

Half-lives span a very wide range (Table 17.5). Consider strontium-90, for which the half-life is 28 a. This nuclide is present in nuclear fallout, the fine dust that settles from clouds of airborne particles after the explosion of a nuclear bomb, and may also be present in the accidental release of radioactive materials into the air. Because it is chemically very similar to calcium, strontium may accompany that element through the environment and become incorporated into bones once there, it continues to emit radiation for many years. About 10 half-lives (for strontium-90, 280 a) must pass before the activity of a sample has fallen to 1/1000 of its initial value. Iodine-131, which was released in the accidental fire at the Chernobyl nuclear power plant, has a half-life of only 8.05 d, but it accumulates in the thyroid gland. Several cases of thyroid cancer have been linked to iodine-131 exposure from the accident. Plutonium-239 has a half-life of 24 ka (24000 years). Consequently, very long term storage facilities are required for plutonium waste, and land contaminated with plutonium cannot be inhabited again for thousands of years without expensive remediation efforts. 

In 1986, a meltdown occurred at this nuclear power plant in Chernobyl, Ukraine. Because there was no containment building, large amounts of radioactive material were released into the environment. Three people died outright, and dozens more died from radiation sickness within a few weeks. Thousands who were exposed to high levels of radiation stand an increased risk of cancer. Today, 10,000 square kilometers of land remain contaminated with high levels of radiation. 

Assessments of the impacts of different radioactive sources on contamination of the Arctic marine environment including water basins, land, and atmosphere. 

The disposal of low-level radioactive waste generated by the U.S. Department of Energy (DOE) during the Cold War era has historically involved shallow land burial in unconfined pits and trenches. The lack of physical or chemical barriers to impede waste migration has resulted in the formation of secondary contaminant sources where... 

On the other hand, there is the question of disposal of domestic and general industrial wastes. There are toxic wastes which require more careful handling. Of particular concern are radioactive wastes from nuclear power stations. With the latter, there are stringent regulations for safe disposal to minimize contamination of the land surface and neighboring surface waters. 

Standards for Cleanup of Land and building Contaminated with Residual Radioactive Materials from Inactive Uranium Processing Sites... 

EPA. 1995a. U.S. Environmental Protection Agency. Standards for cleanup of land and buildings contaminated with residual radioactive materials from inactive uranium processing sites. Code of Federal Regulations. 40 CFR 192, Subpart B. 

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