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
NORM after abandonment - Internal & External Radiation Hazard
TARGET
Reducing 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
g
(Sub)soil activity levels sufficient low.
a
b
g
2
G. Jonkers, GSEA/4 at SRTCA
P.O. Box 38000, 1030 BN Amsterdam
E&P NORM Workshop
Muscat, February 21-24, 2005
tel. +31 20 630 3424
[email protected]
NORM (PRE)TREATMENT OPTIONS
(pre-disposal)
Target
Produced Water
Method
Filtration plant (Matrix [re]injection)
Filtering/Gravity separation
NOR’s [left] in
TDS/TSS
TDS/TSS
Vol. Reduct.
> 99%
> 99%
Sludge
Thermal (physical)
De-oil/de-scale (mechan-/chem-ical)
Bio/chemical/physical ?
Vitrification
Incineration ?
“Solids”
Solids/TDS
“Solids”
“glased solids
slag/fly-ash
> 99%
> 95%
> 95%
> 95% ?
> 95%
Contamination
Scale-water/grit/CO2-pellets Jetting Liquid/Solid
De-scaling (chelating agents)
TDS
Scrap melting
slag/fly-ash
> 95%
> 99%
> 90%
Soil
Wash (mechanical/chemical)
TDS/TSS
> 95%
Waste
Immobilisation (bitumen/polymers)
drums
~ 0%
3
G. Jonkers, GSEA/4 at SRTCA
P.O. Box 38000, 1030 BN Amsterdam
E&P NORM Workshop
Muscat, February 21-24, 2005
tel. +31 20 630 3424
[email protected]
Isolation from Environment
NORM FINAL DISPOSAL OPTIONS
Dilution into the Environment
Controlled Surface Storage
Injection in Sealed Reservoir
Immobilisation & Sealed
Subsurface Storage
4
G. Jonkers, GSEA/4 at SRTCA
P.O. Box 38000, 1030 BN Amsterdam
E&P NORM Workshop
Muscat, February 21-24, 2005
tel. +31 20 630 3424
[email protected]
Conditional Release Limits (CRL)
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
DOSE
annual limits
Effective Dose in Sievert
gas/oil industry-specific exposure scenario’s
encompassing dedicated radiation
protection controlled work with “NORM”
& potential future public use
NOR-contaminated items
EXPOSURE
scenarios
External & Internal
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 Conditional Release Limits
(CRL’s; only to be applied within the
CONCENTRATION
constraints of the gas/oil industry specific
(limits for air, water, soil)
exposure scenario’s)
Becquerel per m3, L or g
Generic EP or Group operating unit specific scenario’s
Generic CRL’s for EP NORM disposal
CRL (Bq[…]/g)
Condition
Spreading
Sludge farming
Shallow disposal
Deep hole disposal
226Ra
210Pb
228Ra
set of NOR-specific
Unconditional Release Limits
(URL’s; may be applied under all
circumstances)
competent authority enveloping scenario's
URL’s
228Th
226Ra
EU BSS
ICRP 2005
0.5
1
210Pb
5
1
228Ra
1
1
228Th
0.5
1
5
G. Jonkers, GSEA/4 at SRTCA
P.O. Box 38000, 1030 BN Amsterdam
E&P NORM Workshop
Muscat, February 21-24, 2005
tel. +31 20 630 3424
[email protected]
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.
6
G. Jonkers, GSEA/4 at SRTCA
P.O. Box 38000, 1030 BN Amsterdam
E&P NORM Workshop
Muscat, February 21-24, 2005
tel. +31 20 630 3424
[email protected]
Assume Worst Case Scenario, but don’t loose reality
7
G. Jonkers, GSEA/4 at SRTCA
P.O. Box 38000, 1030 BN Amsterdam
E&P NORM Workshop
Muscat, February 21-24, 2005
tel. +31 20 630 3424
[email protected]
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
8
G. Jonkers, GSEA/4 at SRTCA
P.O. Box 38000, 1030 BN Amsterdam
E&P NORM Workshop
Muscat, February 21-24, 2005
tel. +31 20 630 3424
[email protected]
DOSE ASSESSMENT REQUIRES MODELLING
Versatile RESidual RADioactivity code
(all pathways) applicable to
• Soil Contamination (Landspreading,
Cleanup);
• Shallow Burial (Landfill, special fills)
• Deep Burial
Have developed dose assessment,
incl. site/target specific parameters
Specific & In-house (Shell)
• flat source (external radiation,
microshield),
• sludge farming (external & dust)
Deep downhole disposal (matrix or
In-house (Shell)
• Mores,
fracture injection) other in-house
• FORDAM
disciplines
9
G. Jonkers, GSEA/4 at SRTCA
P.O. Box 38000, 1030 BN Amsterdam
E&P NORM Workshop
Muscat, February 21-24, 2005
tel. +31 20 630 3424
[email protected]
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 preand 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]
10
G. Jonkers, GSEA/4 at SRTCA
P.O. Box 38000, 1030 BN Amsterdam
E&P NORM Workshop
Muscat, February 21-24, 2005
tel. +31 20 630 3424
[email protected]
“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 dewatering/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
11
G. Jonkers, GSEA/4 at SRTCA
P.O. Box 38000, 1030 BN Amsterdam
E&P NORM Workshop
Muscat, February 21-24, 2005
tel. +31 20 630 3424
[email protected]
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 sludgescale 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]
G. Jonkers, GSEA/4 at SRTCA
P.O. Box 38000, 1030 BN Amsterdam
E&P NORM Workshop
Muscat, February 21-24, 2005
12
tel. +31 20 630 3424
[email protected]
NORM FINAL DISPOSAL OPTIONS
Isolation from Environment
(approximate CRL´s and costs/drum [1997/9 US data])
•
“Spreading (with dilution)”
•
•
•
•
•
•
•
•
•
•
•
Sludge farming
Burial with Unrestricted Site Reuse
Non-Retrieval of Surface Pipe
NORM Disposal Facility
Commercial Oil Industrial Waste Facility
Commercial Low Level Waste Disposal Site
Burial in Surface Mine
Well Injection
Plugged and Abandoned Well
Hydraulic Fracturing
Salt Dome Disposal
Bq[226Ra]/g
$ 40
2
$ 10
2
5
50
$ 20
200
$ 45
200
$ 400
200
500
$ 120
> 1000
$ 200
> 1000
> 1000
$ 10
> 1000
13
G. Jonkers, GSEA/4 at SRTCA
P.O. Box 38000, 1030 BN Amsterdam
E&P NORM Workshop
Muscat, February 21-24, 2005
tel. +31 20 630 3424
[email protected]
Sustainable Environment
14
G. Jonkers, GSEA/4 at SRTCA
P.O. Box 38000, 1030 BN Amsterdam
E&P NORM Workshop
Muscat, February 21-24, 2005
tel. +31 20 630 3424
[email protected]
Backup Slides
Risk Assessment Matrix
Risk Assessment Matrix
0
1
2
3
No health
effect/injury
Slight health
effect/injury
Minor health
effect/injury
Major health
effect/injury
Reputation
Environment
Assets
People
Severity
CONSEQUENCE
No damage
No effect
No impact
Slight
damage
Minor
damage
Localised
damage
Slight effect
Slight impact
Minor effect
Limited
impact
Considerable impact
Localised
effect
4
PTD or 1 to 3 Major
fatalities
damage
Major effect
National
impact
5
Multiple
fatalities
Massive
effect
International
impact
Extensive
damage
A
Never
heard of
in …..
industry
INCREASING LIKELIHOOD
B
C
D
Heard of
in ….
industry
Incident
has
occurred
in our
Company
Happens
several
times per
year in
our
Company
E
Happens
several
times per
year in a
location
Manage for continuous
improvement
Incorporate risk
reduction
measures &
demonstrate
Intolerable
ALARP
The level of control should depend on the level or risk !
16
G. Jonkers, GSEA/4 at SRTCA
P.O. Box 38000, 1030 BN Amsterdam
E&P NORM Workshop
Muscat, February 21-24, 2005
tel. +31 20 630 3424
[email protected]
Additional Dose
Restrictions
Individual Dose Limit
(1,000 mSv/a)
Source Constraint
(300 – 100 mSv/a)
Exemption
(10 mSv/a)
Intervention
Always
Justifiable
very high
100,000 mSv/a
Intervention
May Be
Justifiable
Typical
10,000 mSv/a
Intervention
Rarely
Justifiable
background
2,400 mSv/a
source
17
G. Jonkers, GSEA/4 at SRTCA
P.O. Box 38000, 1030 BN Amsterdam
E&P NORM Workshop
Muscat, February 21-24, 2005
tel. +31 20 630 3424
[email protected]
ESTABLISHMENT OF GENERAL EXEMPT LIMITS
RISK
Likelihood of Fatal Cancer
DOSE
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
“Forward” Calculation - Applied
for Deriving Unconditional Release
(Exempt) Limits or
for Determining Compliance with
Dose or Risk Standards
Source Dose Constraint
to be endorsed by the
Competent Authority
18
G. Jonkers, GSEA/4 at SRTCA
P.O. Box 38000, 1030 BN Amsterdam
E&P NORM Workshop
Muscat, February 21-24, 2005
tel. +31 20 630 3424
[email protected]
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
19
G. Jonkers, GSEA/4 at SRTCA
P.O. Box 38000, 1030 BN Amsterdam
E&P NORM Workshop
Muscat, February 21-24, 2005
tel. +31 20 630 3424
[email protected]
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%
Terrestrial
21%
Internal
Cosmogenic
1%
Cosmic
17%
20
G. Jonkers, GSEA/4 at SRTCA
P.O. Box 38000, 1030 BN Amsterdam
E&P NORM Workshop
Muscat, February 21-24, 2005
tel. +31 20 630 3424
[email protected]
IONISING RADIATION & CANCER DEVELOPMENT
Radiation hits a molecule of a living cell.
Was that molecule a DNA molecule?
Yes
Radiation may or may not cause damage to the
molecule. Was the DNA molecule damaged?
Yes
Damage to a DNA molecule normally corrects itself.
Was the damage corrected?
No
An error remained in the molecule. Was that error of any
significance to the cell?
Yes
The changed characteristics of the new cells may be
harmless or harmful. Are they harmful?
Yes
Cellular reproduction rate may be too slow for cancer to
develop during the lifetime of the individual. Is that so?
No
Cancer cells may be destroyed by the normal immune
system of the body. Are these cancer cells destroyed?
No
A malignant disease will develop.
No
No
No
Health Effects
to the
Individual
Yes
No
No
Yes
Yes
21
G. Jonkers, GSEA/4 at SRTCA
P.O. Box 38000, 1030 BN Amsterdam
E&P NORM Workshop
Muscat, February 21-24, 2005
tel. +31 20 630 3424
[email protected]
RADIATION RISKS “CONSUMER GOODS”
(comparison of risks expressed in dose units: mSv{/a})
Record static eliminator
Radioactive lightning rod
Gas camping lantern mantle (NORM)
Cooking on Natural Gas (Radon)
Tritium wrist watch
Ionisation smoke detector
Exempt level (PRACTICE IAEA/EU)
Radium wrist watch
Flight Amsterdam-Houston (~ 10 h) v.v.
Building masonry (NORM)
X-Ray Photograph (Chest)
Exempt level (WORK ACTIVITY EU, ICRP-2005)
Living in a Dutch Dwelling (Radon)
Public Limit (ICRP-2005)
(World average) Natural Background Dose
(radioisotopes) Nuclear Medicine (kidney)
X-Ray Photograph (Barium meal)
X-Ray Computed Tomography (CT body)
Worker Limit (ICRP-2005)
0.01
0.5
2.5
5
5
10
10
30
70
70
100
300
950
1000
2400
2500
3500
8500
20000
22
G. Jonkers, GSEA/4 at SRTCA
P.O. Box 38000, 1030 BN Amsterdam
E&P NORM Workshop
Muscat, February 21-24, 2005
tel. +31 20 630 3424
[email protected]
COMPARISON OF RISKS OF (WORKING) LIFE
(fatalities per million per year)
Exempt level - PRACTICE (10 mSv – IAEA/EU)
Clothing & Footwear
Timber & Furniture
Exempt level - WORK ACTIVITY (300 mSv – EU/ICRP)
Textiles
Accidents at Work (UK)
Public dose limit (1,000 mSv/a – ICRP)
Metal Manufacture
Accidents at Home (UK)
Natural Background (world average 2,400 mSv/a)
Construction
Road Accidents (UK)
Coal Mining
Radiation worker Dose limit (20,000 mSv/a - ICRP)
Deep Sea Fishing
Smoker (10 cigarettes/day)
0.5
3.5
10
15
35
50
50
60
100
120
200
200
250
1000
2000
5000
23
G. Jonkers, GSEA/4 at SRTCA
P.O. Box 38000, 1030 BN Amsterdam
E&P NORM Workshop
Muscat, February 21-24, 2005
tel. +31 20 630 3424
[email protected]
Risk to People – What Is Reasonable?
Intolerable
RSSG upper bound for
voluntary risk
10-3
Smoking
all accidental (non disease)
all accidental (non-disease, non transport)
E&P contractors
car driving
Too high
HSE upper bound for
involuntary risk
Compare
options
public acceptance of
voluntary risk
Maintain
precautions
(due care)
Negligible*
10-4
10-5
RSSG/HSE insignificant
public acceptance of
Natural disasters
10-6
public tolerance of
man-made disasters
10-7
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
air transport
Living near nuclear installations
insect bites/flooding in the Netherlands
lightning strikes
explosion of pressure vessel
* Proposed by Health & Safety Executive, UK
24
G. Jonkers, GSEA/4 at SRTCA
P.O. Box 38000, 1030 BN Amsterdam
E&P NORM Workshop
Muscat, February 21-24, 2005
tel. +31 20 630 3424
[email protected]
Unconditional Release Limits (URL)
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
DOSE
annual limits
Effective Dose in Sievert
set of enveloping exposure scenario’s
encompassing all industrial uncontrolled
work with “NORM” leading to
workforce/public exposure
EXPOSURE
scenarios
External & Internal
set of NOR-specific
Unconditional Release Limits
(URL’s; may be applied under all
circumstances)
CONCENTRATION
(limits for air, water, soil)
Becquerel per m3, L or g
competent authority enveloping scenario's
URL’s
226Ra
EU BSS
ICRP 2005
0.5
1
210Pb
5
1
228Ra
1
1
228Th
0.5
1
25
G. Jonkers, GSEA/4 at SRTCA
P.O. Box 38000, 1030 BN Amsterdam
E&P NORM Workshop
Muscat, February 21-24, 2005
tel. +31 20 630 3424
[email protected]
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.
26
G. Jonkers, GSEA/4 at SRTCA
P.O. Box 38000, 1030 BN Amsterdam
E&P NORM Workshop
Muscat, February 21-24, 2005
tel. +31 20 630 3424
[email protected]
Risk of Radiation Doses
Compare with Natural Background Dose
27
G. Jonkers, GSEA/4 at SRTCA
P.O. Box 38000, 1030 BN Amsterdam
E&P NORM Workshop
Muscat, February 21-24, 2005
tel. +31 20 630 3424
[email protected]
28
G. Jonkers, GSEA/4 at SRTCA
P.O. Box 38000, 1030 BN Amsterdam
E&P NORM Workshop
Muscat, February 21-24, 2005
tel. +31 20 630 3424
[email protected]