Naturally occurring radioactive materials

In addition to the background radiation normally found at the surface of the Earth, NORM can also be brought to the surface in the natural gas production process. When NORM is associated with oil and natural gas production, it begins as small amounts of uranium and thorium within the rock. These elements, along with some of their decay elements, notably radium-226 and 

This section is adapted from USDOE, Modem Shale Gas Development in the United States A Primer, U.S. Department of Energy, Washington, DC, 2009. 

When NORM is brought to the surface, it remains in the rock pieces of the drill cuttings, remains in solution with produced water, or, under certain conditions, precipitates out in scales or sludge. The radiation from this NORM is weak and cannot penetrate dense materials such as the steel used in pipes and tanks (Smith et al., 1996). The principal concern for NORM in the oil and gas industry is that, over time, it can become concentrated in field production equipment (API, 2004) and as sludge or sediment inside tanks and process vessels that have an extended history of contact with formation water (BSEEC, 2012). Because the general public does not come into contact with oilfield equipment for extended periods, there is little exposure risk from oilfield NORM. Studies have shown that exposure risks for workers and the public are low for conventional oil and gas operations (BSEEC, 2012 Smith et al., 1996). 

If measured NORM levels exceed state regulatory levels or U.S. Occupational Safety and Health Administration (OSHA) exposure dose risks (29 CFR 1910.1096), the material is taken to licensed facilities for proper disposal. In all cases, OSHA requires employers to evaluate radiation hazards, post caution signs, and provide personal protection equipment for workers when radiation doses could exceed 5 mrem in 1 hour or 100 mrem in any 5 consecutive days. In addition to these federal worker protections, states have regulations that require operators to protect the safety and health of both workers and the public. 

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Conservation of Energy. Because the naturally occurring radioactive materials continued to emit particles, and thus the associated energy, without any decrease in intensity, the question of the source of this energy arose. Whereas the conservation of energy was a firmly estabUshed law of physics, the origin of the energy in the radioactivity was unknown. 

According to the vendor, the technology can be used to (1) remediate water and sludges contaminated with radionuclides and heavy metals, (2) restore gronndwater from mining operations, (3) treat naturally occurring radioactive materials (NORMs) in water or scale from petroleum operations, and (4) remediate man-made radionuclides stored in tanks, pits, barrels, or other containers. 

In the first level of the hierarchy, radioactive waste that arises from operations of the nuclear fuel cycle (i.e., from processing of uranium or thorium ores and production of nuclear fuel, any uses of nuclear reactors, and subsequent utilization of radioactive material used or produced in reactors) is distinguished from radioactive waste that arises from any other source or practice. The latter type of waste is referred to as NARM (naturally occurring and accelerator-produced radioactive material), which includes any radioactive material produced in an accelerator and NORM [naturally occurring radioactive material not subject to regulation under the Atomic Energy Act (AEA)]. 

NAS/NRC (1999a). National Academy of Sciences/National Research Council. Evaluation of Guidelines for Exposures to Technologically Enhanced Naturally Occurring Radioactive Materials (National Academy Press, Washington). 

In addition to the analysis of artificial radionuclides, mass spectrometry is useful for characterizing naturally occurring radioactive materials (NORMs). NORMs consist of Th and... 

Operations and activities which act to concentrate and redistribute naturally occurring radioactive material (NORM) in the environment are numerous and further sources continue to be identified. The following sources have been identified as major contributors ... 

Anthropogenic radioactive contamination of the marine environment has several sources disposal at sea, discharges to the sea, accidental releases and fallout from nuclear weapon tests and nuclear accidents. In addition, discharge of naturally occurring radioactive materials (NORM) from offshore oil and gas production is a considerable source for contamination. 

External exposure is from radiation from sources outside our body, such as radiation from sunlight and man-made and naturally occurring radioactive materials. 

Many other materials have been placed on the restricted lists since this first list. These are listed in 40 CFR 268.32 through 40 CFR 268.39. Among the more critical in the context of laboratory wastes are (1) liquid hazardous wastes having a pH 2, (2) liquid hazardous wastes containing PCBs at concentrations 50 ppm, (3) liquid hazardous wastes that are primarily water and halogenated compounds at concentrations 1000 mg/L and 10,000 mg/L, (4) mixed radioactive/hazardous wastes, and (5) RCRA hazardous wastes that contain naturally occurring radioactive materials. 

AR128 Transition from operation to decommissioning of nuclear installations. No. 420, 14 June 2004. AR129 Extent of environmental contamination by naturally occurring radioactive material (NORM) and technological options for mitigation. No. 419, 9 January 2004. 

Radiochemical methods are primarily concerned with the study of radioactivity in naturally occurring radioactive materials and in other materials in which radionuclides and their compounds are produced by irradiation. The foundation of such studies is the careful measurement of radioactivity in a variety of environmental samples, food samples, radiopharmaceuticals, etc. Such measurement can be divided into two major types ... 

Thus, LLRW is defined more by what it is not than by what it is, that is, LLRW is defined by exclusion. LLRW is radioactive waste that is not HLRW, TRU waste, SNF, or byproduct material (commonly referred to as uranium mill tailings). All of these have separate legal definitions. Naturally occurring radioactive material and technologically enhanced NORM are also defined separately from LLRW but are not currently regulated under federal statute. 

NORM is an internationally adopted acronym for Naturally Occurring Radioactive Material while TENORM stands for Technologically-Enhanced Naturally Occurring Radioactive Material. 

Natural uranium consists of the three radioactive isotopes (see Uranium) namely U, and to a lesser extent with both uranium-238 and uranium-235 being the parent radionuclides of the two independent radioactive decay series (4n + 3) and (4n + 2) respectively, while uranium-234 is a decay product of the uranium-238 series. Therefore, the specific activity of natural uranium (U, ) corresponds to the activities of the three isotopes including all the individual activities of all their decaying radionuclides. Therefore for a naturally occurring radioactive material containing a mass fraction of natural uranium, the specific activities of the two parent radionuclides are given by ... 

Similarly, natural thorium is a mononuclidic element, i.e., it has only one radioactive isotope thorium-232, parent radionuclide of the natural decay chain (4n), therefore, for a naturally occurring radioactive material containing a mass fraction of natural thorium, the specific activity of the parent radionuclide is given by ... 

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