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CHARACTERISATION OF NON-NUCLEAR WASTE AND ITS SOURCES
NEA Workshop on the Management of Non-Nuclear Radioactive Waste 2-4 May 2017
Presented by:
Dr. Douglas Chambers
May 2017
© Arcadis 2017
Mining and Mineral Processing
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All soils and minerals have natural radioactivity
In some cases natural levels can be elevated, in
others, levels can be increased by processing
Elevated radioactivity levels can affect operations
and mine closure
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What is NORM?
“ Naturally Occurring Radioactive Material, not
subjected to regulations under the Atomic Energy Act,
disturbed or altered from natural settings, or present in a
technologically enhanced state due to human activities,
which may result in a relative increase in radiation
exposure and risk to public above background radiation
level. ” [HPS]
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Risks from NORM Minerals
In the majority of
situations, the NORM
concentrations do not
pose potential
problems to the
environment or human
health
Processing of ores can
lead to further
enhancement of the
radioactivity in the
products, by-products,
residues or wastes
But
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TENORM “The physical, chemical, radiological properties and concentrations of NORM have been altered such that there exists a potential for:
Redistribution and contamination of environment media (soil, water,
and air);
Increased environmental mobility in soils and groundwater;
Incorporation of elevated levels of radioactivity in products and
construction material;
Improper disposal or use of disposal methods that could result in
unnecessary and relative high exposure to individuals and
populations via any environmental pathway medium.” [HPS]
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NORM Sources Identified by UNSCEAR 2008 Annex B
Metal mining and smelting
Phosphate industry
Coal mining and power production from coal
Oil and gas drilling
Rare earth and titanium oxide industries
Applications of radium and thorium (historic contaminated sites)
Other –water treatment and other NORM wastes
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Concentration Ranges of Uranium and Thorium Series Radionuclides
0.001 0.01 0.1 1 10 100 1000 10000
Soil, Th-232
Soil, Ra-226
Soil, U-238
Other metal ores, U-238 or Th-232
Bauxite
Phosphates, U-238
Rutile, U-238
Ilmenite, Th-232
Zircon, U-238
Pyrochlore, Th-232
Monazite, Th-232
Uranium ores, U-238
Activity concentration (Bq/g)
Data from
UNSCEAR 2000
Non-optimum use
of regulatory
resources
Optimum use
of regulatory
resources
After Wymer, 2008
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Phosphogypsum Stacks
More than 109 tons of PG in North America
Can be managed as waste or as useful by-product
Current world-wide initiative “Stack Free” to
develop safe uses of PG
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Phosphate NORM
Main contributors to dose related to phosphate:
• external gamma radiation from Ra-226 in soil
• inhalation of radon (and RDP)
Radioactivity was already existing and its distribution has changed.
• At some locations more accessible for exposure
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Tanatalum Raw Materials
All electronic devices with capacitors contain tanatalum
Tantalum raw materials contain radioactivity – uranium
and thorium
Denial of shipment of raw materials to processing sites
can be a problem
An IAEA CRP examined transport of NORM materials
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Activity Concentrations (Bq/g) in Tantalum Raw Materials
Radionuclide Material
Type
Number
of
Shipments Mean
(Bq/g)
Max.
(Bq/g)
Proportion
> 10 Bq/g
(%)
Th-232 Slag 22 6.5 27.8 5
Th-232 Tantalite 45 1.3 11.1 2
U-238 Slag 22 18.8 92.2 23
U-238 Tantalite 45 16.4 68.1 71
Total Slag 22 25.3 96.8 45
Total Tantalite 45 17.7 68.3 78
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Radionuclides from Coal Power Plants Naturally Occurring Radioactive Materials (NORM) are part of
the mineral content and become concentrated in the ash
When concentrated, the “NORM” becomes “TENORM” - Technologically Enhanced Naturally Occurring Radioactive Material
• gas phase as airborne effluents (primarily radon, some particulates)
• solid combustion products (U, Th, Ra and progeny)
Average ash yield of coal burned ~10% by weight – quantity depends on mineral content of coal and boiler type (varies from 3-30%)
Accordingly, the concentration of radionuclides in coal ash TENORM can be 10x greater than in the coal
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TENORM in Coal Ash
10-30 ppm Uranium (7-20 pCi/g) similar to granite and phosphate rocks and black shales
TENORM Activity in Coal Ash
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NORM in Oil and Gas Industry (1)
NORM present at varying concentrations in formations from
which oil and gas are produced
Most NORM contains radionuclides from uranium and thorium
decay chains
Primary radioactive isotopes of concern include:
- Radium-226 (Ra-226)
- Radium-228 (Ra-228)
- Radon-222 (Rn-222)
- Lead-210 (Pb-210)
- Polonium-210 (Po-210)
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NORM in Oil and Gas Industry (2)
Radioactive elements brought to surface with production fluids and typically stay with water phase
Radon follows gas production stream
• Longer-lived radon progeny found in pumps, tanks and product lines associated with ethane/propane processing
During “pigging”, pig scrapes along interior wall of pipeline and material pushed in front of pig and collected by pig trap
• Resulting material in trap may contain elevated levels of NORM from U-238 decay series, specifically Pb-210, Po-210 & Bi-210
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USEPA (1973) Radon Concentration in NG Distribution Line
Radon-222 Concentration (pCi/L)
Area Average Range Chicago 14.4 2.3-31.3
New York City 1.5 0.5-3.8
Denver 50.5 1.2-119
West Coast 15 1-100
Colorado 25 6.5-43
Nevada 8 5.8-10.4
New Mexico 45 10-53
Houston 8 1.4-14.3
Overall 23
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Plating and Implications (2)
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Lead 210 will plate onto surfaces in natural gas,
ethane, and propane lines
Polonium 210, Bismuth 210 accumulate over time as
Lead 210 decays
All three radionuclides will be difficult to detect from
the outside of equipment and pipes
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Marcellus Shale - Observations
Treated frac H20 sludge: 6 - 250 mR/h
Treated frac H20 sludge: BG - 3,000 pCi/g
Gas Well Environs, 45 Pennsylvania sites
– Background: 9.0 mR/h
– Well Pads: 8.7 mR/h
– Well Pits: 9.3 mR/h [some 15-20 mR/h]
Radon in Natural Gas: 37 pCi/L [1-79 pCi/L]
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NORM Waste and By-products
Source: Radiation Level [pCi/g]
low average high
Soils of the United States 0.2 NA 4.2
Geothermal Energy Production Wastes (fact sheet)
10 132 254
Oil and Gas Production Wastes (fact sheet)
Produced Water [pCi/l] 0.1 NA 9,000
Pipe/Tank Scale <0.25 <200 >100,000
Drinking Water Treatment Wastes (fact sheet)
Treatment Sludge [pCi/l] 1.3 11 11,686
Treatment Plant Filters NA 40,000 NA
Waste Water Treatment Wastes (fact sheet)
Treatment Sludge [pCi/l] 0.0 2 47
Treatment Plant Ash [pCi/l 0.0 2 22
Aluminum Production Wastes (fact sheet)
Ore (Bauxite) 4.4 NA 7.4
Product 0.23
Production Wastes NA 3.9-5.6 NA
Coal Ash (fact sheet)
Bottom Ash 1.6 3.5-4.6 7.7
Fly Ash 2 5.8 9.7
Copper Mining and Production Wastes (fact sheet)
0.7 12 82.6
Note: Unless otherwise noted, the radiation level
of each waste is shown in the units pci/gram.
For comparison purposes, the average level
of radium in soil ranges from less than 1
to slightly more than 4 pCi/gram.
"NA" indicates data is not available
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Note: Unless otherwise noted, the radiation level
of each waste is shown in the units pCi/gram.
For of radium in soil ranges from less than 1
to slightly more than 4 pCi/gram.
"NA" indicates data is not available
Source: Radiation Level [pCi/g]
low average high
Fertilizer and Fertilizer Production Wastes (fact sheet)
Ore (Florida) 7 17.3-39.5 6.2-53.5
Phosphogypsum 7.3 11.7-24.5 36.7
Phosphate Fertilizer 0.5 5.7 21
Gold and Silver Mining Wastes (fact sheet)
Rare Earths (Monazite, Xenotime, Bastnasite) Extraction Wastes (fact sheet)
5.7 NA 3224
Titanium Production Wastes (fact sheet)
8.0 24.5
Rutile 19.7 NA
Ilmenite NA 5.7
Wastes 3.9 12 45
Uranium Mining Wastes (fact sheet)
Uranium Mining Overburden low
Uranium In-Situ Leachate Evaporation Pond 3 30 3000
Solids 300 3000
Zircon Mining Wastes (fact sheet)
Wastes 87 68 1300
NORM Waste and By-products …cont’d
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NORM Regulation in Canada NORM is exempt from the application of
the Nuclear Safety and Control Act (NSCA).
Except:
when NORM is associated with the development,
production or use of nuclear energy.
when NORM is imported into Canada or exported from
Canada.
the transport of NORM when the specific activity is
greater than 70 Bq/g (70 kBq/kg).
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NORM Regulation in Canada …cont’d NORM is regulated by the provincial and territorial
governments, each having its own specific
regulations on the handling and disposal of the
material (other than for transport which is federally
regulated).
Canadian Guidelines for the Management of
Naturally Occurring Radioactive Materials have
been developed by the Federal Provincial
Territorial Radiation Protection Committee
(FPtrPC)to harmonize standards throughout the
country and ensure appropriate control over
NORM.
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Industrial Sources There are numerous types of sources
Scrap metal contaminated with NORM or other rad wastes
Industrial irradiation(C0-60, Cs-137) - Sterilization of medical
and pharmaceutical products, food preservation , polymer
synthesis
Industrial radiography -non destructive testing (Cs-137, Co-60)
Radioisotope production (I-131, cyclotron production of PE
radionuclides for PET imaging)
Well logging (rad sources –gamma (Cs-137) and neutron
(Am241Be source), or x-rays), sometimes sources are lost in
wells
Luminizing (e.g., gunsights, exit signs…)
Space travel (RTGs, Po-210, Pu-238,…)
Smoke detectors
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INDUSTRIAL (GAUGES)
Fixed and portable
Gauges may be transferred back to the
supplier, to another licensee or to a waste
disposal organization licensed by the
CNSC.
The inventory should be adjusted
accordingly to reflect any transfers.
Currently most sealed sources from
gauges are transferred to CNL (formerly
AECL) in Canada.
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Medical and Research
Pharmaceutical
Nuclear medicine
Laboratory
Accelerators
Education
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Medical Waste – Nuclear Medicine
Commonly Used Isotopes in Nuclear Medicine are:
I-123
I-131
Tc-99m
F-18
Y-90 microspheres(and many more)
In Canada, all radioactive waste disposals must be
managed and handled as per the CNSC’s Nuclear
Substances and Radiation Devices Regulations.
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LABORATORY WASTE Radioactive waste is segregated accordingly to half-
lives at most Universities and Research Facilities.
Based on the isotope’s half-life waste is segregated
and the nuclear substance is usually stored in a
licensed localized storage facility.
Short-lived isotopes such Tc-99m, P-32, P-33,
S-35 are delay decayed for 10 half-lives prior to
disposal.
If short-lived isotopes are to be disposed of in the
normal waste stream their residual activity has to be
measured and recorded by the institution prior to
disposal usually done in consultation with the
Radiation Safety Officer (RSO).
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LABORATORY WASTE • Long-lived radionuclides are segregated by their
half-life and are disposed of accordingly.
• Commonly used Long-lived radionuclides such
as C-14 and H-3 are transferred to specialized
licensed waste contractors.
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Accelerators Much of the radioactive waste material is bulky solid materials
(especially metals)
Unlike nuclear power wastes, rad wastes from accelerators
– Generally produce little alpha activity (except for special target
materials)
– Less neutron rich radioactive species
– A large array of radionuclides
The main waste streams are
Operational - maintenance replacements, decontamination
materials
Decommissioning - residual operational wastes, structural
concrete, shielding materials
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Concluding Remarks
There are very many kinds of radioactive wastes arising from non-fuel cycle activities
These wastes have a wide variety of radiological, chemical and physical forms
Waste management requirements can lead to costly solutions
In Canada there are few options for commercial disposal of radioactive wastes that cannot be managed by storage and decay