Selected values of chemical thermodynamic properties ::Part …
Selected values of chemical thermodynamic properties ::Part 8 Compounds of Uranium, Protactinium, Thorium, Actinium, and the Alkali Metals Published January 1, 1981
Radiation Regulations and Laws | Radiation Protection | US EPA
Health and Environmental Protection Standards for Uranium and Thorium Mill Tailings (40 CFR Part 192) This regulation sets standards for the protection of the public health, safety and the environment from radiological and non-radiological hazards associated with uranium and thorium ore processing, and disposal of associated wastes.
Regulation of Radioactive Materials | NRC.gov
The NRC regulates the use of these radioactive materials through Title 10, Part 20, of the Code of Federal Regulations ( 10 CFR Part 20 ), "Standards for Protection Against Radiation," which spells out the …
Determination of trace concentrations of thorium in uranium …
An epithermal instrumental neutron activation analysis (EINAA) method using cadmium filter was standardized to determine trace concentrations of thorium in four samples of uranium oxide (U3O8) samples. Samples and thorium standards, wrapped with cadmium foil, were irradiated at a reactor neutron flux of about 1012 cm−2 s−1. …
A comparison of analytical methods for determining uranium and thorium
Standard and samples were diluted with 5% HNO 3 (Holmes and Pilvio, 2000). 2.3.3. Alpha spectrometry. ... The uranium and thorium concentrations obtained with the above-mentioned methods are presented in Table 5, Table 6, respectively. Table 5. Uranium concentrations (ppm) in Talvivaara and Sokli samples measured with ICP-MS, …
Food and drinking water | IAEA
International standards relating to the control of radioactivity in food and drinking water have been developed by the Food and Agricultural Organization of the United Nations (FAO), the IAEA and the World Health Organization (WHO). ... Naturally occurring radioactive material, such as potassium-40, polonium-210, thorium-232 and uranium …
Radiation Regulations and Laws | Radiation Protection | US …
This regulation sets standards for the protection of the public health, safety and the environment from radiological and non-radiological hazards associated with uranium and thorium ore processing, and disposal of associated wastes. In January 2017, EPA proposed revisions to 40 CFR 192 that would establish groundwater restoration and …
Thorium
Thorium as a nuclear fuel. Thorium (Th-232) is not itself fissile and so is not directly usable in a thermal neutron reactor. However, it is 'fertile' and upon absorbing a neutron will transmute to uranium-233 (U-233) a, …
RELEASE STANDARD FOR URANIUM AND THORIUM …
The appropriateness of developing a separate unrestricted release standard for uranium and thorium at levels higher than those in 10 CFR 20.1402 is being considered given that : 1) source material specific licensees are currently required to cleanup sites where source ... uranium and thorium exist elsewhere in nature; 2) some of these sites ...
Health and Environmental Protection Standards for …
Health and Environmental Protection Standards for Uranium and Thorium Mill Tailings. A Proposed Rule by the Environmental Protection Agency on 10/30/2018. …
Uranium and thorium in urine of United States residents
We found uranium at detectable concentrations in 96.6% of the urine specimens and thorium in 39.6% of the specimens. The 95th percentile concenetration for uranium was 34.5 ng/L (parts per trillion); concentrations ranged up to 4080 ng/L. Thorium had a 95th percentile concentration of 3.09 ng/L; concentrations ranged up to 7.7 ng/L.
Determination of lead, uranium, thorium, and thallium in …
@article{osti_4489166, title = {Determination of lead, uranium, thorium, and thallium in silicate glass standard materials by isotope dilution mass spectrometry}, author = {Barnes, I L and Garner, E L and Gramlich, J W and Moore, L J and Murphy, T J and Machlan, L A and Shields, W R and Tatsumoto, M and Knight, R J}, abstractNote = {}, doi = …
PART 192—HEALTH AND ENVIRONMENTAL …
part 192—health and environmental protection standards for uranium and thorium mill tailings Authority: Sec. 275 of the Atomic Energy Act of 1954, 42 U.S.C. 2022, as added by the Uranium Mill Tailings Radiation Control Act of 1978, Pub. L. 95-604, as …
The half-lives of uranium-234 and thorium-230
NBL-112a is a uranium metal standard purified from natural uranium ore. The uranium assay is 99.975±0.006% and the relative atomic weight is 238.0289. Our thorium gravimetric standard is a solution made from electrotransport purified thorium metal prepared by the Standard Materials Preparation Center, Ames Laboratory …
Radiation Regulations and Laws | US EPA
Health and Environmental Protection Standards for Uranium and Thorium Mill Tailings (40 CFR Part 192) This regulation sets standards for the protection of the …
Uranium–thorium dating method and Palaeolithic rock art
The uranium/thorium dating method gives reliable and relatively precise results in the case of massive speleothems, because the sampling is carried out at the heart of the material where the hypothesis of a closed system (that is, no exchange with the outside environment) is justified in most cases. Unfortunately, the situation is quite ...
Health and Environmental Protection Standards for Uranium and Thorium
On this page: Rule Summary; Rule History; Rule Summary. This regulation sets standards for the protection of public health, safety and the environment from radiological and non-radiological hazards associated with uranium and thorium ore processing, and disposal of associated wastes. The cross-media standards apply to pollution emissions and site …
Regulation of Radioactive Materials | NRC.gov
Byproduct material (material that is made radioactive in a reactor, and residue from the milling of uranium and thorium) The NRC regulates the use of these radioactive materials through Title 10, Part 20, of the Code of Federal Regulations ( 10 CFR Part 20 ), "Standards for Protection Against Radiation," which spells out the agency's ...
Uranium, Thorium, and XRF Analysis of Heavy Metals
10.24.2013. Both Uranium (U) and Thorium (Th) are silvery-white metallic chemical elements. According to the World Nuclear Association, Thorium is a naturally-occurring, slightly radioactive metal, and can be used in conjunction with fissile material as nuclear fuel. And the basic fuel for a nuclear power reactor is Uranium – a heavy metal ...
Radiation Regulations, Standards, and Guidance
Cleanup Standards for Land: radium-226 (at uranium sites) or. radium-228 (at thorium sites) in land averaged over any area of. 100 square meters shall not exceed background by more than. 5 pCi/g in the 15 cm surface layer and 15 pCi/g in any 15 cm. layer below the surface layer. compliance and closure schedules.
Health and Environmental Protection Standards for …
This includes source material (uranium and thorium), special nuclear material (enriched uranium and plutonium), by-product material (e.g., material made radioactive in a …
Pb, U and Th diffusion in natural zircon | Nature
Here we present direct measurements of the uranium, thorium and lead loss from a thermally treated gem-quality natural zircon and show that lead diffuses much faster than uranium or thorium ...
40 CFR Part 192: Proposed Rulemaking and Background Documents …
Blog entries on Uranium-Thorium Mill Tailings Standards from Greenversations. Electronic docket (EPA-HQ-2012-0788-0001) on Regulations.gov. Published Sources Used in the Proposed Rulemaking of January 26, 2015. Groundwater Restoration at Uranium In-Situ Recovery Mines, South Texas Coastal Plain (36 pp, 3.16 …
Thorium
Thorium, like uranium, survives on Earth because it has isotopes with long half-lives, such as the predominant one, thorium-232, whose half life is 14 billion years. ... National Institute of Standards and Technology, Gaithersburg, MD, accessed November 2016. T. L. Cottrell, The Strengths of Chemical Bonds, Butterworth, London, 1954. Uses and ...
Determination of lead, uranium, thorium, and thallium in …
Isotopic composition of commercially available uranium chemicals and elemental analysis standards. Journal of Radioanalytical and Nuclear Chemistry 2018, 316 (2), 791-798.
Potential Human Health Effects of Uranium Mining, …
The radionuclides of greatest health-related concern in uranium mining and processing are those present in the uranium-238 (238 U), uranium-235 (235 U), and thorium-232 (232 Th) decay series. The potential for occupational exposure to uranium or thorium and their decay products can vary greatly depending on numerous factors, …
40 CFR Part 192: Proposed Rulemaking and …
Health and Environmental Protection Standards for …
WEBThe Environmental Protection Agency (EPA) is proposing to add new health and environmental protection standards to regulations promulgated under the Uranium …
Standard Test Method for Analysis of Uranium and Thorium …
5.1 This test method was developed and the instrument calibrated using ground soils from the site of a nuclear materials plant. This test method can be used to measure the extent of contamination from uranium and thorium in ground soils. Since the detection limit of this technique (nominally 20 μg per gram) approaches typical …
Health and Environmental Protection Standards for Uranium and Thorium
As we explained in the 2015 Proposal, "in 1983, EPA originally promulgated regulations at 40 CFR part 192, Health and Environmental Protection Standards for Uranium and Thorium Mill Tailings, in response to the statutory requirements of the Atomic Energy Act [AEA] of 1954, as amended by the Uranium Mill Tailings Radiation Control …
Health and Environmental Protection Standards for Uranium and Thorium
Rule Summary; Rule History; Rule Summary. This regulation sets standards for the protection of the public health, safety and the environment from radiological and non-radiological hazards associated with uranium and thorium ore processing, and disposal of associated wastes. The cross-media standards apply to pollution emissions and site …
