NORM Final Disposal Options (risk & cost considerations) Gert Jonkers

1. NORM Final Disposal Options (risk & cost considerations) Gert Jonkers Engineering & Analytical - GSEA/4 “Problem Solving” (Shell E&P Ionising Radiation/NORM HSE Expert CHP) location Shell Research & Technology Centre, Amsterdam P.O. 38000 NL-1030 BN Amsterdam the Netherlands

2. g NORM after abandonment - Internal & External Radiation Hazard TARGETReducing both External and Internal Dose by Naturally Occurring Radionuclides in Deposits (NORM ) from former Gas/Oil Production Activities to a Negligible Level for Future Inhabitants Ingestion Determine amount of radioactivity in the food chain. Inhalation Potential (topsoil) dust activity levels extremely low. External (Sub)soil activity levels sufficient low. a b g

3. NORM (PRE)TREATMENT OPTIONS (pre-disposal) Target Method NOR’s [left] in Vol. Reduct. Produced Water Filtration plant (Matrix [re]injection) TDS/TSS > 99% Filtering/Gravity separation TDS/TSS > 99% Sludge Thermal (physical) “Solids” > 99% De-oil/de-scale (mechan-/chem-ical) Solids/TDS > 95% Bio/chemical/physical ? “Solids” > 95% Vitrification “glased solids > 95% ? Incineration ? slag/fly-ash > 95% Contamination Scale-water/grit/CO2-pellets Jetting Liquid/Solid > 95% De-scaling (chelating agents) TDS > 99% Scrap melting slag/fly-ash > 90% Soil Wash (mechanical/chemical) TDS/TSS > 95% Waste Immobilisation (bitumen/polymers) drums ~ 0%

4. Isolationfrom Environment NORM FINAL DISPOSAL OPTIONS Dilution into the Environment Controlled Surface Storage Injection in Sealed Reservoir Immobilisation & Sealed Subsurface Storage

5. Conditional Release Limits (CRL) DOSE annual limits Effective Dose in Sievert EXPOSURE scenarios External & Internal CONCENTRATION (limits for air, water, soil) Becquerel per m3, L or g radiation workers 20,000 mSv/a workers (2,000 h/a) 1,000 mSv/a public 1,000 mSv/a NORM- source constraint 300 mSv/a to be issued and endorsed by the competent authority for radiation workers, workforce/public at large source constraint for dose control set of enveloping exposure scenario’s encompassing all industrial uncontrolled work with “NORM” leading to workforce/public exposure gas/oil industry-specific exposure scenario’s encompassing dedicated radiation protection controlled work with “NORM” & potential future public use NOR-contaminated items set of NOR-specific Conditional Release Limits (CRL’s;only to be applied within the constraints of the gas/oil industry specific exposure scenario’s) set of NOR-specific Unconditional Release Limits (URL’s; may be applied under all circumstances) Generic EP or Group operating unit specific scenario’s competent authority enveloping scenario's Generic CRL’s for EP NORM disposal URL’s CRL (Bq[…]/g) 226Ra210Pb 228Ra 228Th Condition Spreading Sludge farming Shallow disposal Deep hole disposal 226Ra 210Pb 228Ra 228Th EU BSS 0.5 5 1 0.5 ICRP 2005 1 1 1 1

6. Dose Assessment Study  Conditional Release Limit (referenced against the NORM Source Constraint defined the Competent Authority) • Collection/compilation of site specific data characterising the (geo)hydrological setting, climate conditions, background radiation levels and radioactivity concentration in various environmental media including soil, subsoil, surface water, ground water, airborne dusts, fauna and flora. • Identification and quantification of the source terms (input of NORM for intended final disposal option), the chemical and physical form of the radionuclides the points of release, and the time distribution of release. • Identification of the potential environmental pathways. • Identification of the critical population, defining (conditional) scenarios • Assessment of the individual dose using a computer modelling.

7. Assume Worst Case Scenario, but don’t loose reality

8. NORM FINAL DISPOSAL. • Environmental exposure acceptability • Public acceptability • Economic acceptability • Universal acceptability • Time to make the option viable • Time for industry use once the option is viable

9. DOSE ASSESSMENT REQUIRES MODELLING • Versatile RESidual RADioactivity code (all pathways) applicable to • Soil Contamination (Landspreading, Cleanup); • Shallow Burial (Landfill, special fills) • Deep Burial • Specific & In-house (Shell) • flat source (external radiation, microshield), • sludge farming (external & dust) Have developed dose assessment, incl. site/target specific parameters Deep downhole disposal (matrix or fracture injection) other in-house disciplines • In-house (Shell) • Mores, • FORDAM

10. Dilution into the Environment Sludge farming (Landspreading) with dilution includes mixing of the applied wastes thoroughly within the topsoil. The area covered may be arbitrarily large. Analyses of landspreading with dilution also are based on incremental increase of NOR concentrations above background levels, and thus are also restricted to one-time disposal in a given area (record-keeping!). 0.2 <> 5 Bq[226Raeq]/g Grinding (de-oiled) scales to a prescribed particle size distribution and subsequent overboard disposal dilutes these materials into the marine environment. Disposal is based on incremental increase of NOR- concentrations above natural marine background levels. Record-keeping and possible radiation surveys to characterise pre- and post-spreading radiation levels around platforms are measures to control the impact on the marine environment. < 5 Bq[226Raeq]/g[solid] Cleanup criteria for soil contamination. Scraping of contaminated soil, leaving remnant (residual) radioactivity levels. < 5 Bq[226Raeq]/g[soil]

11. “Controlled Disposal” Land based burial with unrestricted site re-use may occupy any available land area with minimal or no groundwater(flow). There may be some requirements like de-watering/oiling, solidification, consolidation, packaging (crates, boxes, drums) or compaction, before the waste is actually buried in (lined) trenches, more than 2.5 m deep (intrusion limit). After burial the trenches generally are capped with clay or other low-permeability cover material, gravel drainage layers and a topsoil layer. Capping the waste with concrete prevents erosion or water leaching. In arid climates, measures may be taken (e.g. dumping of large rock material on top) to discourage temporarily dwelling construction (e.g. Bedouins), while in other climates sites are contoured and replanted with vegetation for drainage and erosion control.This disposal method may also be applied to NOR-contaminated items. Strongly related option is burial of “NORM” sludge and scale in (deep) surface mines. Possibly with some pre-treatment requirements “NORM” is placed at the bottom of mine excavations and is subsequently buried by accumulated earthen overburden. Typical burial depths are 15 m or greater, and areas are sufficient to accommodate relatively large volumes of wastes. Because of the significant burial depths, the potential for erosion or intrusion into the wastes is remote. Other designated (municipality, oilfield waste, hazardous material, low level) waste sites may take NORM waste. 5 <> 200 Bq[226Raeq]/g

12. Deep Geological Disposal Engineered deep underground geological disposal facilities for high or intermediate level waste final disposal may be available. These facilities are used c.q. have been proposed due to their inherent isolation of the wastes from groundwater and from the surrounding environment. Salt provides impermeable containment of wastes at depths of 1,000 m or more. The salt formation tends to self-anneal any containment defects that may occur, further assuring containment of the wastes. NOR-contaminated sludge, scale and/or gas/oil field items can also be placed in salt domes. Salt caverns have been used to store various hydrocarbon products and to dispose normal oilfield waste. Matrix injection consists of injecting produced water into a deep permeable formation below underground sources of drinking water with no fresh water or mineral value. The formation is confined by impermeable layers that are likely to remain intact. Fracturing injection consists of adding sludges and pulverised scales to a carrier fluid (typically brine) and pumping the mixture into a well of sufficiently high pressure to create a fracture in a permeable formation below underground sources of drinking water with no fresh water or mineral value. The fracture formed by this process is normally vertical, confined above and below by impermeable shale formations. After the sludge-scale water mixture is displaced into the fracture, pressure is reduced and the fracture closes and NORM becomes trapped. Fill a well to be abandoned with NORM encapsulated in connected tubulars (encapsulation), after well is plugged and abandonded. 1,000 Bq[226Raeq]/g[solid]

13. NORM FINAL DISPOSAL OPTIONS (approximate CRL´s and costs/drum [1997/9 US data]) Isolationfrom Environment • B q[226Ra]/g • “Spreading (with dilution)”$ 40 2 • Sludge farming $ 10 2 • Burial with Unrestricted Site Reuse 5 • Non-Retrieval of Surface Pipe 50 • NORM Disposal Facility $ 20 200 • Commercial Oil Industrial Waste Facility $ 45 200 • Commercial Low Level Waste Disposal Site $ 400 200 • Burial in Surface Mine 500 • Well Injection$ 120 > 1000 • Plugged and Abandoned Well $ 200 > 1000 • Hydraulic Fracturing > 1000 • Salt Dome Disposal $ 10 > 1000

14. Sustainable Environment

15. Backup Slides

16. Risk Assessment Matrix The level of control should depend on the level or risk !

17. Intervention Always Justifiable Intervention May Be Justifiable Intervention Rarely Justifiable very high 100,000 mSv/a Additional Dose Restrictions Individual Dose Limit (1,000 mSv/a) Source Constraint (300 – 100 mSv/a) Exemption (10 mSv/a) Typical 10,000 mSv/a background 2,400 mSv/a source

18. ESTABLISHMENT OF GENERAL EXEMPT LIMITS RISK Likelihood of Fatal Cancer Source Dose Constraint to be endorsed by the Competent Authority DOSE “Forward” Calculation - Applied for Deriving Unconditional Release (Exempt) Limits or for Determining Compliance with Dose or Risk Standards Effective Dose in Sievert EXPOSURE Derived Limits to be endorsed by the Competent Authority for any circumstance (Unconditional) External & Internal CONCENTRATION (air, water, soil) Becquerel per m3, L or g

19. HIERARCHY OF DOSE QUANTITIES Absorbed Dose (Gy) energy imparted by radiation to unit of mass of tissue (J/kg) Equivalent Dose (Sv) absorbed dose weighted for harmfulness of different radiations (wR) Effective (Whole Body) Dose (Sv) equivalent dose weighted for susceptibility to harm of different tissues (wT) Collective Effective Dose (manSv) effective dose to all people exposed to a source of radiation

20. EXPOSURE OF NATURAL ‘BACKGROUND’ RADIATION Everyone is Exposed to Natural Background Radiation Worldwide Population Averaged Natural Radiation Dose: 2,400 µSv/y Internal Terrestrial (excl radon/thoron) 12% Internal Radon 47% Internal Thoron 3% Internal Cosmogenic 1% Terrestrial 21% Cosmic 17%

21. IONISING RADIATION & CANCER DEVELOPMENT No Health Effects to the Individual No Yes No Yes Yes No No Yes No Yes Yes No No Radiation hits a molecule of a living cell. Was that molecule a DNA molecule? Radiation may or may not cause damage to the molecule. Was the DNA molecule damaged? Damage to a DNA molecule normally corrects itself. Was the damage corrected? An error remained in the molecule. Was that error of any significance to the cell? The changed characteristics of the new cells may be harmless or harmful. Are they harmful? Cellular reproduction rate may be too slow for cancer to develop during the lifetime of the individual. Is that so? Cancer cells may be destroyed by the normal immune system of the body. Are these cancer cells destroyed? Yes A malignant disease will develop.

22. RADIATION RISKS “CONSUMER GOODS” (comparison of risks expressed in dose units: mSv{/a}) Record static eliminator 0.01 Radioactive lightning rod 0.5 Gas camping lantern mantle (NORM) 2.5 Cooking on Natural Gas (Radon) 5 Tritium wrist watch 5 Ionisation smoke detector 10 Exempt level (PRACTICE IAEA/EU) 10 Radium wrist watch 30 Flight Amsterdam-Houston(~ 10 h) v.v. 70 Building masonry (NORM) 70 X-Ray Photograph (Chest) 100 Exempt level (WORK ACTIVITY EU, ICRP-2005) 300 Living in a Dutch Dwelling (Radon) 950 Public Limit (ICRP-2005) 1000 (World average) Natural Background Dose 2400 (radioisotopes) Nuclear Medicine (kidney) 2500 X-Ray Photograph (Barium meal) 3500 X-Ray Computed Tomography (CT body) 8500 Worker Limit (ICRP-2005) 20000

23. COMPARISON OF RISKS OF (WORKING) LIFE (fatalities per million per year) Exempt level - PRACTICE (10 mSv – IAEA/EU) 0.5 Clothing & Footwear 3.5 Timber & Furniture 10 Exempt level - WORK ACTIVITY (300 mSv – EU/ICRP) 15 Textiles 35 Accidents at Work (UK) 50 Public dose limit (1,000 Sv/a – ICRP) 50 Metal Manufacture 60 Accidents at Home (UK) 100 Natural Background (world average 2,400 Sv/a) 120 Construction 200 Road Accidents (UK) 200 Coal Mining 250 Radiation worker Dose limit (20,000 Sv/a - ICRP) 1000 Deep Sea Fishing 2000 Smoker (10 cigarettes/day) 5000

24. - 3 10 - 4 10 - 5 10 - 6 10 - 7 10 Risk to People – What Is Reasonable? Smoking all accidental (non disease) all accidental (non-disease, non transport) E&P contractors RSSG upper bound for voluntary risk Intolerable Too high Compareoptions Maintainprecautions(due care) Negligible* car driving accidents at home E&P company staff accidents at work (average all industries – US ’86) playing football/rock climbing Fire Workers in safest industry Light manufacturing HSE upper bound for involuntary risk public acceptance of voluntary risk air transport Living near nuclear installations RSSG/HSE insignificant public acceptance of Natural disasters insect bites/flooding in the Netherlands lightning strikes explosion of pressure vessel public tolerance of man-made disasters * Proposed by Health & SafetyExecutive, UK

25. Unconditional Release Limits (URL) DOSE annual limits Effective Dose in Sievert EXPOSURE scenarios External & Internal CONCENTRATION (limits for air, water, soil) Becquerel per m3, L or g radiation workers 20,000 mSv/a workers (2,000 h/a) 1,000 mSv/a public 1,000 mSv/a NORM- source constraint 300 mSv/a to be issued and endorsed by the competent authority for radiation workers, workforce/public at large source constraint for dose control set of enveloping exposure scenario’s encompassing all industrial uncontrolled work with “NORM” leading to workforce/public exposure set of NOR-specific Unconditional Release Limits (URL’s; may be applied under all circumstances) competent authority enveloping scenario's URL’s 226Ra 210Pb 228Ra 228Th EU BSS 0.5 5 1 0.5 ICRP 2005 1 1 1 1

26. Dose Assessment Study  Conditional Release Limit (referenced against the NORM Source Constraint set by the Competent Authority) • Collection/compilation of site specific data characterising the geohydrological setting, background radiation levels and radioactivity concentration in various environmental media including soil, subsoil, surface water, ground water, airborne dusts, fauna and flora. • Identification and quantification of the source terms (input of NORM for intended final disposal option), the chemical and physical form of the radionuclides the points of release, and the time distribution of release. • Identification of the potential environmental pathways. • Identification of the critical population. • Assessment of the individual dose using a computer modelling.

27. The End The End Risk of Radiation Doses Compare with Natural Background Dose