NORM And TENORM: A New Legal Normal?
Definitions � NORM N aturally O ccurring R adioactive M aterials � Radioactive materials that are found in nature. They have been part of the natural environment since the earth was formed. � TENORM T echnologically E nhanced NORM � Naturally Occurring Radioactive Materials where: � concentration of NORM has been increased by human activity, or � human activity of relocating or processing NORM has increased its radiation exposure potential to humans.
PRIMORDIAL RADIONUCLIDES � Primordial (terrestrial) radionuclides and their progeny are naturally present in rocks, soil, water, and air. Among them are: � U-238 (13 radioactive progeny) � U-235 (11 radioactive progeny) � Th-232 (10 radioactive progeny) � K - 40 (no radioactive progeny)
NORM DISTRIBUTION IN THE EARTH’S CRUST � Geological and hydrogeological processes have caused the accumulation, leaching, migration, and redeposition of radionuclides in the Earth’s crust. � As a result, the spatial distribution of radionuclides in the crust and crustal fluids is very heterogeneous. � Even within the Marcellus Shale, the distribution is heterogeneous.
U-238 DECAY SERIES
TH-232 DECAY SERIES
AVERAGE NORM CONCENTRATIONS IN THE EARTH’S CRUST Nuclide Average Activity/Concentration 238 U and 234 U 0.1 to 32 pCi/g in common soil and rock types; 99.27 % of all uranium 232 Th 0.02 to 16.7 pCi/g in common soil and rock types; crustal average is approximately 2.4 pCi/g 226 Ra and 228 Ra 0.1 to 16.0 pCi/g in soil and rock 40 K 1 to 33 pCi/g
ELEVATED NORM CONCENTRATION STRATA � Coal seams � Phosphate-rich marine deposits � Some granites � Some sandstones � Monazite (a rare earth phosphate mineral) � Marine black shales
Impacted Industries And Processes � Metals Mining � Rare Earth Extraction � Phosphates/Fertilizer Production � Oil and Gas Production � Geothermal Production � Coal Fired Energy Production � Water Treatment Residuals
Marine Black Shales � Radionuclides in ocean water absorbed by plankton and concentrated in organic on the ocean floor. � This accumulation of organic matter leads to an organic- rich black shale, with higher than average concentration of uranium. � K-40 and Th-232 preferentially adhere to clays. � Because marine black shales contain more organic matter and clay, they are generally more radioactive than other shales or sedimentary rocks. � “Natural Gamma” logging detects gamma radiation in rock and is frequently used to identify productive gas and oil zones during drilling.
Radionuclides And Groundwater � Uranium and thorium are not very soluble in normal groundwater. � Radium reacts like calcium and is more soluble. � Radium migration in groundwater may result in elevated levels of radon, polonium, and bismuth in groundwater. � Ra-226 and Ra-228 usually have similar activity. � In Marcellus Shale, however, Ra-226 activities are greater. � Radium activities increase with increasing salinity and Total Dissolved Solids.
Sources of Radionuclides in Oil and Gas Producti on � Drill cuttings and drilling mud � Produced water � HF flowback water � Filtration wastes and sediment from processing of production water and flowback water � Sludge and scale in drilling equipment and pipes � Scale is precipitated minerals on pipe and tank surfaces
Location of Oilfield NORM EXPLANATION Green = Oil production Orange = Gas production Yellow = Mixed production
From NORM to TENORM � Some practices can increase the level of radiation to create TENORM � Waterflood – recirculating brine for enhanced recovery � Hydraulic Fracturing – increased fluid making contact with NORM geology � Reuse of frac water – has a similar effect to waterfloods � As these practices become more common, TENORM becomes more common
The “Martha” Oil Field - Kentucky � The Martha Oil Field was discovered in 1919 � A large waterflood project was begun in 1955 to extract more oil. � The producing formation contained high levels of Ra-226. � The water and brine injections into the formation concentrated the Ra-226 and brought it to the surface. � The elevated radiation were discovered in 1988 when pipes hauled from the field tripped a scrap yard’s radiation detector.
HF: The New TENORM Focus
Sources/Drilling � Cuttings � Vertical – Typically low (natural) TENORM concentrations, some moisture content, varying grain size � Horizontal – Typically low (natural) TENORM concentrations, sometimes measurably higher than vertical, some moisture content, varying grain size � Mud � Typically low (natural) TENORM concentrations, initially saturated, varying grain size
Sources/HF - Flowback Water � Produced Water � ~90% Dissolved solids - relatively high TENORM concentrations; process mobilizes Ba & chemical analogs (Ra) � ~10% suspended solids – relatively low TENORM concentrations, similar to solids in cuttings and mud � Water Processing � Sludge – Solids removed from flowback water � Physical Filtration – suspended solids – moderate TENORM concentrations � Chemical Processing – Dissolved & suspended solids � Relatively high TENORM concentrations � Rn off-gassing
Sources/Flow Back Water � Scale on impacted pipes and equipment � Contains relatively high concentrations of radium � Typically innocuous during normal operation � Scale removal produces solid waste and airborne radioparticulates
NORM/TENORM Regulation: Federal � Nuclear Regulatory Commission � Atomic Energy Act – 42 U.S.C. § 2011, et seq � Environmental Protection Agency � Safe Drinking Water Act - 42 U.S.C. § 300f � Clean Water Act - 33 U.S.C. § 1251, et seq � Clean Air Act - 42 U.S.C. § 701, et seq � Resource Recovery and Conservation Act (RCRA) – 42 U.S.C. § 9601, et seq - � Department of Transportation � Hazmat Transportation � Department of Labor � OSHA Standards
NORM/TENORM Regulation: States � Environmental Regulation � Oil and Gas Regulation � Solid Waste Regulation � Health Regulation � Worker Safety
Federal Regulation/NRC � NORM � Not specifically regulated by the Atomic Energy Act of 1954 � Included in NRC definition of “background radiation” (10 C.F.R. § 20.1003): � “[R]adiation from cosmic sources; naturally occurring radioactive material, including radon (except as a decay product of source or special nuclear material); and global fallout as it exists in the environment from the testing of nuclear explosive devices or from past nuclear accidents such as Chernobyl that contribute to background radiation and are not under the control of the licensee. " Background radiation " does not include radiation from source, byproduct, or special nuclear materials regulated by the Commission.
Federal Regulation/NRC � TENORM � Not specifically regulated under the Atomic Energy Act of 1954 � Under the Atomic Energy Act, the NRC’s authority over radioactive materials is limited to source , special nuclear , and byproduct materials, or those materials that are generally associated with the nuclear fuel cycle. � NRC regulates TENORM as “Source Material” (i.e. unenriched uranium or thorium) if it exceeds the “unimportant quantities of source material” limit which is (>0.05%wt U nat , Th nat ).
NRC/Source Material � NRC regulates TENORM as “Source Material” (i.e. unenriched uranium or thorium) if it exceeds the “unimportant quantities of source material” limit which is (>0.05%wt U nat , Th nat ). � “Source Material” – 10 C.F.R. § 20.1003 � “(1) Uranium or thorium or any combination of uranium and thorium in any physical or chemical form; or (2) ores that contain, by wright, one-twentieth of 1 percent (0.05 percent), or more, of uranium, thorium, or any combination of uranium and thorium. Source material does not include special nuclear material”.
NRC/Special Nuclear Material � 10 C.F.R. § 20.1003 defines “Special Nuclear Material” � “(1) Plutonium, uranium-233m uranium enriched in the isotope 233 or in the isotope 235, and any other material that the Commission, pursuant to the provisions of § 51 of the Act, determines to be special nuclear material, but does not include source material; or (2) any material artificially enriched by any of the foregoing but does not include source material.”
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