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8/8/2019 International Association of Oil & Gas Producers - Guidelines handling Natural Occuring Radioactive Material (NORM)
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Guidelines or the management o Naturally OccurringRadioactive Material (NORM) in the oil & gas industry
Report No. 412
September 2008
I n t e r n a t i o n a l A s s o c i a t i o n o f O i l & G a s P r o d u c e r s
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Publications
Global experience
Te International Association o Oil & Gas Producers has access to a wealth o technicalknowledge and experience with its members operating around the world in many dierentterrains. We collate and distil this valuable knowledge or the industry to use as guidelinesor good practice by individual members.
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Our overall aim is to ensure a consistent approach to training, management and best prac-tice throughout the world.
Te oil and gas exploration and production industry recognises the need to develop consist-ent databases and records in certain elds. Te OGPs members are encouraged to use theguidelines as a starting point or their operations or to supplement their own policies andregulations which may apply locally.
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Tis document may provide guidance supplemental to the requirements o local legislation. Nothingherein, howeer, is intended to replace, amend, supersede or otherwise depart om such requirements. Inthe eent o any conict or contradiction between the provisions o this document and local legislation,
applicable laws shall preail.
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Guidelines or the management o Naturally OccurringRadioactive Material (NORM) in the oil & gas industry
Report No: 412
September 2008
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able o contents
1 Introduction 1
. Te Origins o Naturally Occurring Radioactive Material (NORM) . . . . . . . . . . . . . . . . . . . . . . . . . . .
. NORM in Scale . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
.3 NOR M in Sludge and Scrapings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
. NOR M in Gas Processing Facilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
.5 NORM in Seawater Injection Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
.6 Health Hazards o NORM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
.7 Environmental Problems Associated with NORM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2 NORM Management Process Cycle 11
3 NORM Monitoring 13
3. Baseline surveys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
3. Pre-shutdown surveys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
3.3 Operational assessments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33. Legacy contamination surveys. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4 NORM Action Limits 16
5 Training and Awareness 17
6 Contamination Control 18
7 Control o NORM Contaminated Waste 20
7. NORM disposal options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8 Control o NORM Contaminated Equipment 23
9 Decontamination 25
9. Operating criteria . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
9. Required operating areas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
9.3 Control o equipment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
9. Inspection o equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
9.5 Monitoring o equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
10 Workers Protection Requirements 29
11 Confned Space Entry 30
12 Transport o NOR M Contaminated Equipment 31
13 Documentation 33
Glossary o Terms 34
Radiation units 35Reerences 36
Further reading 36
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Naturally occurring radionuclides are present at varying concentrations in the Earths crust andcan be concentrated and enhanced by processes associated with the recovery o oil and gas. Tisenhanced NORM, oen known as ENORM (echnologically-Enhanced Naturally Occur-
ring Radioactive Materials) can be created when industrial activity increases the concentrations oradioactive materials or when the material is redistributed as a result o human intervention or someindustrial processes, ENORM also can be the by-product or waste product o oil, gas and geo-thermal energy production. Sludge, drilling mud, and pipe scales are examples o materials that cancontain elevated levels o NORM, and the radioactive materials may be moved rom site to site asequipment and materials are reused.
Uncontrolled activities associated with enhanced levels o NORM can contaminate the environ-ment and pose a risk to human health. Tese risks can be alleviated by the adoption o controls toidentiy where NORM is present; and by the control o NORM-contaminated equipment and waste
while protecting workers. Te general principles o radiation protection are primarily implementedby means o good protective measures at the workplaces. Hence, exposure control and adequate
dosimetry are the most critical components o a health and saety programme.Tere are various national and international regulations and guidelines on radiation protection ingeneral and NORM in particular. Tese are not specic to the oil & gas industry and there are vari-ations in the methods o control adopted. Tis document has been developed aer research, reviewand thorough consideration o readily available NORM regulations and guidelines, to determinebest practice or managing NORM in oil and gas producing acilities. Similarly, there is no universalmedical surveillance programme or low-level radiation exposures. Medical surveillance is typicallytriggered by an exceedance o a dened action level. An action level is a scientically derived valueused or the purpose o limiting exposure. Action levels oen vary rom country to country so thatthe reader must understand the applicable regulations in a given locale.
Tis document acts as a road map and establishes uniorm approaches on NORM management
that makes the implementation o tasks easy to manage. Te guidance does not seek to obstruct orimpede normal operations but to describe controls that are adapted to working practices. Te guide-lines are exible and accommodate regulatory variations under which individual OGP membercompanies may be required to operate.
Te guidance acts as a single point o reerence, is user-riendly and utilises owcharts to guide thereader through dierent NORM management activities. It guides the user through the various com-
ponents o an eective NORM management process.
It must be stressed, however, that these guidelines provide a ramework. Users should realise thatmanagement o NORM requires the consultation and engagement o a number o stakeholders,notably the approval o the regulatory authorities.
1.1 The origins o Naturally Occurring Radioactive Material (NORM)
Radioactive materials such as Uranium and Torium were incorporated in the Earths crust whenit was ormed; these normally exist at trace (parts per million ppm) concentrations in rock orma-tions. Decay o these unstable radioactive elements produces other radionuclides that, under certainconditions (dependent upon pressure, temperature, acidity etc) in the subsurace environment aremobile and can be transported rom the reservoir to the surace with the oil & gas products beingrecovered.
During the production process, NORM ows with the oil, gas and water mixture and accumulatesin scale, sludge and scrapings. It can also orm a thin lm on the interior suraces o gas processing
equipment and vessels. Te level o NORM accumulation can vary substantially rom one acility toanother depending on geological ormation, operational and other actors. o determine whetheror not a acility has NORM contamination, NORM survey, sampling and analysis needs to be con-ducted. Figure . indicates where NORM may accumulate, egat wellheads in the orm o scale; at
Introduction
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Gas/Oil Separation Plants (GOSP) in the orm o sludge; and at gas plants the orm o thin lms asthe result o radon gas decay.
Table 1.1 Mean and range of Thorium and Uranium concentration in sedimentary rock (Reference 1)
Sedimentary Rock Class
Thorium (Th) Uranium (U)
(ppm) Bq[232Th]/g (ppm) Bq[232Th]/g
mean range mean mean range mean
Detrital 12.4 0 362 0.05 4.8 0.1 80 0.06
Sandstone &Conglomerate
9.7 0.7 227 0.04 4.1 0.1 62 0.05
orthoquartzites 1.5 0.006 0.5 0.5 3 0.005
arkoses 5 0.02 1.5 0.02
Shale 16.3 5.3 39 0.07 5.9 0.9 80 0.07
grey/green 13 0.05 3 3 4 0.04
black 8 20
Clay 8.6 1.9 55 0.03 4.0 1.1 16 0.05
Chemical 14.9 0.03 132 0.06 3.6 0.03 27 0.04
Carbonates 1.8 0 11 0.007 2.0 0.03 18 0.02
Limestones 3 0.01 13 0.16
Evaporites < 0.1 < 0.001
Tere are three types o radiation emitted by NORM, namely;
Alpha ()
Beta ()
Gamma ()
Alpha particles are helium nuclei that are heavy and doubly (positively) charged which causes themto lose their energy very quickly in matter. Tey can be stopped by a sheet o paper or the suracelayer o your skin. Alpha particles are considered hazardous to a persons health only i a radioactivesource o alpha emitting particles is inhaled or ingested.
Beta particles are much smaller and only have one (negative) charge, which causes them to interactmore slowly with material. Tey are eectively stopped by thin layers o metal or plastic and areagain considered hazardous only i a beta emitter source is ingested or inhaled.
Gamma emitters are associated with alpha, beta decay and are a orm o high energy electromagneticradiation that interacts lightly with matter. Gamma rays are best shielded by thick layers o lead or
other dense materials and are considered as an external hazard to living tissues (ie the human body).Figure . details the penetrating power o ionising radiation emitted rom NORM radionuclides.
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Figure 1.1 The origins of NORM, indicating where NORM may accumulate in the recovery process.
Gas
Oil
Water
???Ra,228Ra,210Pb,222Rn
Particulate scaleand ???Rn,
Condensate 222Rn
and particulate scale
226Ra, 228Ra, 224Ra, 222Rn
238U, 232Th
Ra isotopes precipitate as mineral scale
Mobilise with hydrocarbons and produced water
222Rn migrates with gas
222Rn,210Pb,210Po plates tubular
GOSP
Table 1.2 Activity concentration of238U, 226Ra, 210Pb and 232Th, 228Ra, 224Ra in production water (Reference 1)
Radionuclide Reported Range (Bq/l)
238U 0.0003 0.1
226Ra 0.002 1,200
210Pb 0.05 190
232Th 0.0003 0.001
228Ra 0.3 180
224Ra 0.5 40
Table 1.3 Activity concentration of238U, 226Ra, 210Po and 232Th in crude oil (Reference 1)
Radionuclide Reported Range (Bq/g)238U 0.0000001 0.01
226Ra 0.0001 0.04
210Po 0 0.01
232Th 0.00003 0.002
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Figure 1.2 Penetration power of ionizing radiation (Reference 2)
Paper Plastic Steel Lead
Tissue
NORM Decay Series
Te NORM nuclides o primary concern in oil production are Radium-6 and Radium-. Tesedecay into various radioactive progeny, beore becoming stable lead. Radium-6 belongs to theUranium-3 decay series and Radium- to the Torium-3 decay series.
Te two principal radioactive decay series (Uranium-3 and Torium-) associated with NORMin the oil & gas industry are detailed in Figures .3 & .. Tese gures show the radionuclides oconcern, their radioactive hal-lives, decay mechanism, and the manner in which they are mobi-lised.
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Figure 1.3 Uranium-238 decay series (Reference 3)
a) Naturally occurringradionuclides
Transport withreservoir
b) LeachingTransport with water
c) Emanation/
dissolutionTransport with gas/
(oil/water)
d) MechanismTransport via water
(gas/oil) carrier leadcompounds
e) MechanismTransport via NGL/
condensate
238U 109y
234Th
234mPa
234U
230Th
226Ra 1600y
222Rn 4d
218Po
214Pb
214Bi
214Po
210
Pb 22y
210Bi
210Po 138d
206Pb stable
226Ra
222Rn
218Po
214Pb
214Bi
214Po
210
Pb
210Bi
210Po
206Pb
222Rn
218Po
214Pb
214Bi
214Po
210
Pb
210Bi
210Po
206Pb210Po
206Pb
210Pb
210Bi
210Po
206Pb
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Figure 1.4 Thorium-232 decay series (Reference 3)
a) Naturally occurringradionuclides
Transport withreservoir
b) LeachingTransport with water
232
Th 10
10
y
228Ra 6y
228Ac
228Th 2y
224Ra 4d
220Rn
216Po
212Pb
212Bi
212Po &208Ti
208Pb stable
b) LeachingTransport with water
224Ra
220Rn
216Po
212Pb
212Bi
212Po &208Ti
208Pb
224Ra
220Rn
216Po
212Pb
212Bi
212Po &208Ti
208Pb
228Ra
228Ac
228Th
1.2 NORM in scale
Te main types o scale encountered in oil & gas acilities are sulphate scale such as BaSO, SrSO
and carbonate scale such as CaCO3. Radium is chemically similar to barium (Ba), strontium (Sr) and
calcium (Ca), hence radium co-precipitates with Sr, Ba or Ca scale orming radium sulphate, radiumcarbonate and in some cases radium silicate.
Te mixing o seawater, which is rich in sulphate, with the ormation water, which is rich in brine,increases the scaling tendency. Also the sudden change in pressure and temperature or even acidityo the ormation water, as it is brought to the surace, contributes to scale build-up. Te build-upo scale on the interior o a pipe is shown in Figure .5. Tis phenomenon has signicant implica-tions or the production o oil; in this case the capacity o the pipe to transer oil would be reducedsignicantly.
Table 1.4 Activity concentration of238U, 226Ra, 210Pb, 232Th and 228Ra in hard scales (Reference 1)
Radionuclide Repor ted Range (Bq/g)
238U 0.001 0.5
226Ra 0.1 15,000
210
Pb 0.02 75210Po 0.02 1.5
232Th 0.001 0.002
228Ra 0.05 2,800
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Figure 1.5: Scale build-up on internal pipe surface
Table 1.5 Activity concentration of238U, 226Ra, 210Pb, 232Th and 228Ra in soft/medium hard scales (Reference 1)
Radionuclide Repor ted Range (Bq/g)
238U 0.001 0.05
226Ra 0.8 400
210Pb 0.05 2,000
232Th 0.001 0.07
228Ra 0.05 300
1.3 NORM in sludge and scrapings
Radioactive molecules containing radium which were not incorporated into scale can be oundin sludge, produced sands and produced waters. Other radionuclides such as Lead- and Polo-nium- can also be ound in pipelines scrapings as well as sludge accumulating in tank bottoms,gas/oil separators, dehydration vessels, liquid natural gas (LNG) storage tanks and in waste pits as
well as in crude oil pipeline scrapings.
Table 1.6 Activity concentration of238U, 226Ra, 210Pb, 210Po, 232Th and 228Ra in sludges (Reference 1)
Radionuclide Repor ted Range (Bq/g)238U 0.005 0.01
226Ra 0.05 800
210Pb 0.1 1,300
210Po 0.004 160
232Th 0.002 0.01
228Ra 0.5 50
Table 1.7 Activity concentration of226Ra, 210Pb and 228Ra in scrapings (Reference 1)
Radionuclide Repor ted Range (Bq/g)
226Ra 0.01 75
210Pb 0.05 50
210Po 0.1 4
228Ra 0.01 10
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1.4 NORM in gas processing acilities
Radon is a radioactive gas, which is present in varying degrees in natural gas in oil & gas ormations.
In the absence o natural gas, radon dissolves in the (light) hydrocarbon and aqueous phase. Whenproduced with the oil and gas, radon will usually ollow the gas stream. I the natural gas is raction-ated, a disproportionately high percentage o radon can concentrate in the propane streams and to alesser degree in the ethane streams.
Radon- produces, through natural decay, several radioactive nuclides (also known as radon prog-eny). Most radon progeny are short-lived, with the exception o Lead- and Polonium-, whichhave relatively long hal-lives o .6 years and 3 days respectively. Most o the radon decay prod-ucts (9-99%) are attached to ambient aerosols, airborne particulates or suraces. Tis can result inorming thin radioactive lms on the inner suraces o gas processing equipment such as scrubbers,compressors, reux pumps, control valves and product lines.
Table 1.8 Activity concentration of222Rn, 210Pb and 210Po in natural gas (Reference 1)
Radionuclide Reported Range (Bq/m3)
222Rn 5 200,000
210Pb 0.005 0.02
210Po 0.002 0.08
Table 1.9 Activity concentration of210Pb and 210Po in NGL/hydrocarbon condensate (Reference 1)
Radionuclide Repor ted Range (Bq/l)
222Rn (NGL) 0.01 1,500
222Rn (C3 -liq) 0.01 4,200
210Pb 0.3 230
210Po 0.3 100
1.5 NORM in seawater injection systems
Uranium exists in seawater in part per billion (g/l) concentrations. Te use o seawater or recoveryo oil rom a reservoir can potentially introduce an additional enhanced NORM scenario. In ananaerobic environment (such as in a geological ormation), sulphate-reducing bacteria have beenshown to enhance the uptake o uranium which is deposited in bio-ouling deposits , 5. In manyseawater injection systems this may not pose a signicant hazard, however, systems which utiliselarge quantities o seawater may encounter levels o uranium in bio-ouling which present a risk to
workers and a problem or waste disposal. Concentrations o uranium up to ~% by weight havebeen identied in seawater injection systems, 5.
1.6 Health hazards o NORM
Tere are two ways in which personnel can be exposed to NORM, namely:
Irradiation external exposure where the source remains outside the body
Contamination internal exposure where radioactive material is taken into the body via inha-lation, ingestion or absorption
Tere is a large body o scientic research and literature on the health eects o ionizing radiationexposure. Te health eects associated with exposure to ionising irradiation vary depending on thetotal amount o energy absorbed, the time period, the dose rate and the particular organ exposed. Akey consideration related to NORM is that exposures are generally quite low and below established
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regulatory action levels. In some situations, exposure to low-level ionising radiation may not result inany adverse health eects; hence the basis or developing regulatory health-based action levels.
Exposure to NORM will not result in acute and severe eects similar to those eects associated withexposure to high radiation levels rom man-made sources. Chronic exposure to NORM above expo-sure limits or the general public or ollowing inadequate saety precautions are typically delayedeects such as the development o certain orms o cancer. A variety o cancers has been associ-ated with exposure to ionising radiation including leukaemia, and cancers o the lung, stomach,oesophagus, bone, thyroid, and the brain and nervous system. It is important to understand that the
potential health eects are strongly dose-related. In addition, based on extensive scientic study overmany decades, radiation exposure is not associated with all orms o cancer.
Medical surveillance or low-level radiation exposures is typically triggered by exceedance o anestablished regulatory action level. However, medical surveillance is an imperect and non-specictool. It is dicult to nd medical tests that detect meaningul abnormal changes in a timely ashion.Most medical tests do not have high sensitivity or specicity, ie the ability to correctly identiy who
has a problem (sensitivity-true positive) and who does not have a problem (specicity- true nega-tive). All medical tests have various levels o sensitivity (alse positive) and specicity (alse negative).Tere is no perect set o tests or every potential health concern. Tereore, while medical surveil-lance is a standard strategy that is oen used, it must be emphasised that source control, exposuremonitoring, worker education and sae operating practices are the most important strategies or
preventing signicant worker exposures.
Potential NORM exposure scenarios are detailed in Figure .6.
Figure 1.6 NORM exposure scenarios (Reference 6)
Irradiation Contamination
Alpha
Beta
Gamma
Gamma
Gamma
NORM materials may become an inhalation risk when the material is dislodged by mechanicalorces, such as wire brushing, pipe rattlingetc.
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Table 1.10 Observed external radiation levels at the outside of processing facilities (Reference 1)
Facility Radiation Level# (Sv/h)
Crude oil processing/treating
down hole tubing, safety valves (internal) up to 300
well heads, production manifolds 0.1 2.5
production lines 0.3 4
separator scale (internal) up to 200
separator scale (external) up to 15
water outlets 0.2 0.5
Associated/natural gas processing/treating
downhole tubing 0.1 2.2
piping, filters, storage tanks, reflux lines up to 80
sludge pits, brine disposal/injection wells, brine storage tanks up to 50
NGL processing
filters up to 90
NGL pump up to 200
C3
storage tanks up to 60
NGL/C 3 shipping pumps, C3 reflux pumps, elbows, flanges 0.1 2.8
1.7 Environmental problems associated with NORM
Handling, storage, transportation and the use o NORM contaminated equipment or waste mediawithout controls can lead to the spread o NORM contamination, and result in contamination oareas o land, resulting in potential exposure o the public.
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o ensure that all aspects o NORM management are highlighted, structured and managed, the ol-lowing process cycle has been developed. Te process cycle indicates where action and controls maybe required to ensure adequate protection o workers, public and the environment in a practical and
cost eective manner. Te process cycle is detailed in Figure ..
It is important that NORM management is planned and carried out ollowing consultation andengagement o stakeholders. Specically, the approval o the regulatory authorities will be required.NORM management is not an activity that companies can undertake independently, given the con-tentious nature o radioactivity and radioactive material.
A strategy or NORM management in the process cycle is essential, i management is to be success-ul. Key areas to be considered are:
NORM monitoring
Control o NORM contaminated waste
Control o NORM contaminated equipment
Worker protection and training
Development o NORM management guidelines
Compliance monitoring.
Te owcharts provided in this document are generic, high-level charts and require many tasks,documents and systems to enable them to unction eectively; they indicate where main controlsand documentation are required. A general plan or NORM management which would t with theabove process cycle is shown in Figure ..
Figure 2.1 NORM management process cycle
NORMmonitoring
Normal operation
Identify NORMcontaminated
equipment/waste
NORMdetected?
Additionalradiological risks
NORM freeequipment
DecontaminateNORM equipment
Interim storage ofNORM contaminated
equipment
Workers protection &contamination control
measures
NORM waste interimstorage
Release forgeneral use
NORM wastepermanentdisposal
Yes
No
NORMwaste
NORMwaste
NORMcontaminatedequipment
NORMcontaminatedequipment
Normal operation
Hazard exists ontrolled hazard
afe disposal options
NORM management process cycle
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Figure 2.2 NORM management generic plan
NORM survey NORMdetected?
Conduct riskassessment
Normaloperation
Workersprotection
issue?
Develop workprocedures/instructions
Plan the operation,including contingency
planning
Implement theplan/carry out
operation
NORM waste issue
Take representativesamples for
radiometric analysis
Waste aboveaction level?
ApprovedNORM storage/
disposal
Normal disposalroute
Document/recordsurvey
Document workprocedures/instructions
Record sampleanalysis data
Document operation
Document riskassessment
Document plan
Record storage/disposal information
Yes
No
No
Yes
No
Yes
Normal operation
Hazard exists
ontrolled hazard
afe disposal options
Documentation/data
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Monitoring is required to ascertain whether NORM is present in a medium. It can utilise directmeasurement instruments which can be taken to the onshore or oshore elds to measure the levelso radiation emitted. Alternatively, samples can be collected and sent to a laboratory or radiomet-
ric analysis. In practice, a monitoring programme will usually make use o all available monitoringmethods and techniques based on specic requirements o individual organisation. Various compo-nents o a monitoring programme may include:
Baseline surveys
Pre-shut-down surveys
Operational assessments
Legacy contamination surveys.
3.1 Baseline surveys
Te objective is to establish a baseline o the spread and level o NORM accumulation in acilities.Tis inormation is essential in determining which category o workers needs protection and type ocontamination control procedure. Baseline surveys also yield important inormation about NORM
waste streams that is essential input toward developing NORM waste disposal solutions.
Te ollowing are examples o where baseline surveys could be considered:
Vessels in oil/gas separation acilities
Wellheads.
3.2 Pre-shutdown surveys
Te objective is to determine the locations o NORM accumulation in acilities where NORM con-tamination is suspected. One example would be gas/oil separation acilities; where a survey shouldbe undertaken prior to a shutdown. I a positive indication is shown by gamma radiation detectors,then the presence o NORM inside vessels/tanks is clearly indicated. Tis conrms the need orestablishing worker protection and contamination control measures. It also indicates that there maybe NORM waste which requires to be handled in a controlled manner.
3.3 Operational assessments
Te objective is to enable eld organisations to identiy NORM contamination promptly during
routine operational scenarios. In operating acilities, situations arise where workers might need toconduct intrusive work, such as clean up or maintenance, on potentially NORM contaminatedequipment or entry into potentially contaminated vessels. In such situations, eld personnel shouldbe capable o conducting NORM assessments using portable and easy-to-use instruments to deter-mine the presence o NORM contamination.
Te ollowing are examples o operational components where NORM may be detected:
Down-hole tubing, saety valves, etc
Long piping runs
Well heads
Production maniolds
Flow-lines (to gas/oil separators)Separators (high, intermediate, and low pressure)
Dehydrators
Desalinators
3 NORM monitoring
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Valves
Gas/oil separator bafe plates
Oil storage tanks.
3.4 Legacy contamination surveys
Legacy contamination is contamination which results rom operations beore the implementationo a NORM management strategy. Areas with potential legacy NORM contamination include, butare not limited to, land disposal sites, evaporation ponds, disposal pits and areas used or equipmentstorage, cleaning , and maintenance where NORM contamination was potentially accumulated overtime.
Te requirements or an eective NORM survey as stated below are detailed in Figure 3..
Personnel who are required to monitor levels o radiation and contamination associated withNORM should be trained in the use o the instrumentation and the interpretation o the readings/measurements (see raining & Awareness). Tere are many actors which aect the eciency o aradiation detector and personnel who are required to monitoring NORM levels should be aware othese. For example, surace coatings o water or oil/grease would attenuate any NORM contami-nation present on the surace and give a lower than anticipated indication on the detector. Manysuraces may be dicult to directly monitor due to their surace condition or geometry and there-ore both direct (probe measurement) and indirect (smear/swab) means o survey are required. Te
probe must also be held very close to the surace to ensure optimum detection eciency or theemitted radiation as both alpha and beta particles have relatively short range in air and gamma rayintensity will decrease in line with the inverse square law away rom the source o activity. rainingrequirements or those required to use radiation detectors to monitor levels o NORM are detailed
in section 6 o this document.In practice, it is unlikely that alpha and/or beta particles will be unsupported and not have associ-ated gamma rays. However or the purposes o hand held instruments, surveyors need to have detec-tors which will respond to alpha/beta particles and gamma rays. Unortunately, there is no detectorthat measures all three types o radiation, thereore a minimum o two dierent detectors is berequired to characterise the NORM present in acilities adequately.
Suitable handheld radiation detectors or use in the assessment o NORM contamination are:
Alpha/beta, an uncompensated Geiger-Muller tube (pancake type detector): this will respondto alpha, beta and gamma however when used in the eld its measurements should be used as anindicator rather than a quantiable measurement, due to many actors which will aect the detec-tors ability to respond.
Gamma, a sodium-iodide (NaI) scintillation detector: this provides a very quick response and issensitive at low energy ?-emissions, such as those associated with NORM decay.
Other types o instruments can be used, but it is important to be aware o the limitations o eachdetection system.
Te majority o radiation detectors are not intrinsically sae and their use in operational acilitieswill require the use o a hot work permit or its equivalent. Tere are now some intrinsically saedetectors.
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Figure 3.1: Schematic of NORM survey requirements
NORMmonitoring
required
Trainedpersonnelavailable?
Training records
Train personnel orcontact trained
personnel
Select appropriatedetectors
Instruments incalibration and
functioning?Obtain work permits
Send for repair/calibration
Carry out backgroundcheck
Carry out survey
Inform proponent ofsurvey findings
Return instruments tostorage for re-use
Instruments incalibration and
functioning?
Instrument calibrationrecords
Instrument/surveyprocedure
Record survey results Report survey results
No
Yes
No
Yes
No
Yes
Normal operation Controlled hazard afe disposal options Documentation/data
Table 3.1 Suitable radiation detector types for Alpha, Beta and Gamma emissions from NORM
Radiation type Instrument type Remarks
Alpha UncompensatedGM tube
Probe must be as close to the surface as possible without touchingit, alpha only has a short range in air and will be attenuated on
wet surfaces. In NORM radionuclides alpha usually always has anassociated gamma emission.
Beta UncompensatedGM tube
As above, although beta has a slightly greater range in air.
Gamma(screening)
Sodium iodide Very sensitive gamma detector which will give a very quick indicationif enhanced gamma levels are present. It can potentially over-estimategamma dose-rates so should not be used to quantify only detect.
Gamma(measurement)
CompensatedGM tube
Slower responding instrument, which will however give a moreaccurate indication of gamma dose-rate.
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Te action limits or the disposal/control o NORM waste material may be stipulated in Nationalregulations. However, in the absence o National Regulations, the ollowing limits can be utilisedand these will provide or compliance with current international practice:
Materials and waste media such as sludge/scale containing NORM at levels below those listedin able 5. shall be exempted rom the requirements o this procedure.
Soil shall not have a Radium-6 contamination above .5 Bq per gram (5 pCi per gram)above background averaged over any square metres or unless risk assessment demonstratesan acceptable level o risk.
Equipment, vessels, and clothing shall be considered NORM contaminated i internal orexternal surace contamination measures double the radiation background level.
Table 4.1 NORM exemption levels
Radionuclide Exemption level (Bq/g) Exemption level (pCi/g)
226Ra 1.1 30
228Ra 1.1 30
210Pb 0.2 5
210Po 0.2 5
238U 5.5 150
Uranium (nat) 3.0 80
NORM action limits
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raining and awareness are major components o a NORM management system. Workers need tobe made aware o the hazards associated with NORM, the controls that are required or their pro-tection and the methods or preventing environmental contamination.
raining should ocus on operational personnel who are potentially exposed to NORM and directlyinvolved in maintenance operations. Key personnel should be identied and provided with trainingthat will permit them to ensure that the work they do pays due regard to the hazards o NORM and
prevents the spread o NORM contamination.
Workers awareness can be enhanced through NORM awareness sessions.
A ormally structured training programme provides training in the ollowing areas:
Workers course
Surveyors course
Supervisors course/Radiation Saety Ocers course.
Figure 5. details the training identication, ormulation and review process, together with coreknowledge and documentation requirements.
Figure 5.1 Training development process and core knowledge topics
Corporate RadiationProtection Authority
National regulatoryrequirements NORM Workers
Training requirementsfor each category
Identify the categoriesof persons to be
trained
The training processfor education and
competence building
Corporaterequirements NORM Surveyors
Corporate training
programme NORM Supervisor
Training records NORM RadiationSafety Officers
Origins of NORM Radiation and contamination Biological effects of radiation Risks associated with radiation exposure to NORM
Comparisons of other radiation sources personnelare exposed to everyday
Worker protection from NORM Emergency response procedures
Feedback & evaluation
All NORM worker information plus: Survey instruments NORM legal limits Survey documentation Sampling operations Air sampling Types of laboratory analysis Area posting requirements A practical session involving the actual survey for
NORM to be included in the curriculum
All NORM worked course and NORM surveyor
course information should be taught in addition to thefollowing topics: Waste management programme Surveying plans and programmes Record keeping requirements Shipping and transporting radioactive material The ALI and DAC Disposal options Liability minimisation
This module is designed to provide personnelassigned as Radiation Safety Officers (RSO) orNORM Field Supervisors the detailed knowledge andpractical abilities necessary to implement and monitora Radiation Protection Programme. All topics coveredin the NORM Worker, Surveyor and Superv isorcourses are covered. Additionally, all aspects ofRadiation Protection and NORM Waste ManagementProgrammes, along with problems and solutionsfacing the RPO are covered in detail. A thoroughreview and understanding of all applicable nationaland company regulations will be provided. Thiscourse includes an extensive NORM surveyingpractical session and examination.
Normal operation
Controlled hazard
Documentation/data
5 raining and awareness
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Te ollowing are basic control procedures that should be practised when handling NORM con-taminated equipment, tubulars, vessels, pipes or machinery:
Establish a boundary around the work area. Te boundary should be as small as possible, butlarge enough to allow or personnel and equipment access rom the work area and to allow orall work to be accomplished in a sae manner. Containers or plastic bags should be provided ordiscarded protective clothing and contaminated trash at the exit o the work area.
Only essential personnel should be allowed in the work areas where potential NORM contami-nation exists.
Prior to maintenance o contaminated equipment or opening inspection hatches, sludge trapsor pig receivers, sucient ground cover shall be placed below the item in the work area. Teground cover should be made o a plastic, waterproo type material capable o withstanding the
work activities involved without tearing or ripping. Alternatively, a suitable drip-tray or catch-pan may be used. Te ground cover should be sized to provide or the containment o leakageand waste and to allow ample room or related peripheral work.
Post the boundary with radiation warning signs Caution: NORM Material: (with radiationtreoil)
Hold a saety meeting or all personnel perorming work. Radiological items which should beaddressed during the meeting are, but are not limited to, protective clothing and respiratory
protection requirements, radiation and contamination levels, maintenance activities which maycause radioactive material to become airborne, requirements or waste generated, heat stress,action to be taken in the case o emergencies.
Commence maintenance activity; any dry material that is NORM-contaminated should bewetted down to prevent the generation o airborne radioactive materials. Dry material shouldbe wetted periodically throughout the maintenance work.
Openings o equipment or pipes that have internal NORM contamination should be sealed orwrapped by plastic or other suitable materials.
Obsolete NORM-contaminated pipes or equipment should be clearly labelled as NORMContaminated Materials and removed to a designated area. Te area should be labelled asContaining Radioactive Materials and restricted or the general public.
All contaminated waste generated during maintenance should be drummed or or put into con-tainers and marked or labelled. Representative samples should be collected rom the waste andanalysed or radioactivity.
Upon completion o maintenance, personnel should remove their protective clothing beoreleaving the work area.
All material, equipment and tools not placed in containers or drummed should be surveyedor both loose contamination and exposure rate levels upon exit rom the work area. A readinggreater than background levels is positive indication o contamination, and should be handledas such.
Upon job completion, the accessible areas o the work area should be surveyed or loose contami-nation. Any loose surace contamination ound should be promptly cleaned up and drummed.
Once the work area has been veried ree o loose surace contamination, the boundary andpostings may be taken down.
A schematic diagram o a potential contamination control system or the removal o a valve is shownin Figure 6.. Te diagram indicates what controls are required, ega physical barrier (red line) to
prevent unauthorised access, plastic sheeting/ground cover to catch any NORM contamination andprevent contamination o work area , separate entrance and exit to prevent spread o contaminationetc.
6 NORM contamination control procedures
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Figure 6.1 NORM contamination control requirements
g
b
a
b
b
aa
a
Valve removed andsealed for cleaning
Specialdrain
Washing facility& towels
UsedPPE
Entrance
Exit
NewPPEGround
cover
PPE: Personnel Protective Equipment
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Beore NORM can be managed eectively, it is necessary to know where it is being produced. Tisrequires an assessment o all process that identiy potential NORM contamination.
NORM waste disposal must adhere to applicable regulations pertaining to the disposal o radioac-tive waste.
In many cases short-term or interim storage may be required beore nal disposal o NORM waste.Where NORM waste is required to be stored, it should be kept in suitable container which shouldcomply with the ollowing requirements. Te container;
Should be in good condition with no visible indications o internal or external corrosion, andbe made o a durable material such that it provides adequate containment o the NORM wasteduring the storage period.
Should be made o or lined with materials that will not react with or be incompatible with theNORM waste so that the ability o the container is not impaired or compromised.
Should be resistant to degradation by Ultra Violet radiation.
Should be closed and sealed during storage, and practical to open and re-seal when it is neces-sary to add or remove waste.
Should not be opened, handled, or stored in a manner that may rupture the container or causeit to leak.
Should bear the radiation symbol and a label clearly indicating that it contains NORM con-taminated waste.
Should pay due regard to any other materials which may be present in the NORM waste matrix(ie oils, grease or chemicals etc)
Should be resistant to normally expected range o temperature in storage environment.
Should be resistant to water ingress.
Should be stored in a dry environment to prevent corrosion.
Should be physically robust to prevent damage during transport.
Te storage location should be hard suraced and bunded to prevent contamination o ground/surace waters and the creation o contaminated land rom any potential leaks/spills as a resulto incidents during storage period.
Areas where containers o NORM waste are stored should be inspected on a regular basis. Contain-ers should be inspected or signs o leakage, overall deterioration and proper labelling. Records othese inspections should be documented and properly maintained.
Where NORM waste is disposed o, records shall be maintained o the disposal activities. Teseshould include but not limited to:
Waste material description (scale, sludge, scrapings, etc)Volume o waste materia l
Mass
NORM level (activity per unit weight) o waste material.
Method o disposal
Disposal location
Organisation/acility where the NORM waste was generated
Any other relevant inormation.
7 Control o NORM contaminated waste
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7.1 NORM disposal options
Te objective is to establish sae, practical and cost eective permanent disposal protocols or
NORM waste that provide adequate protection to both human health and the environment.A permanent disposal protocol should be designed to prevent contamination o natural resourcessuch as underground water, or contamination o soil that could in uture become residential or agri-cultural areas even although the area is currently remote or uninhabited.
Methods o NORM disposal currently used in the oil & gas industry are:
Land based management
Salt cavern disposal
Oshore discharge
Land ll
Underground injection
Te preliminary selection criteria may include:
Risk
echnical easibility
Cost
General acceptance (regulatory and public)
Table 7.2 Description of disposal methods (Reference 6)
Disposal Method Description
Land spreading Land spreading involves disposal by spreading sludge and scale on thesurface/open lands in an area where NORM was not originally present above
background levels.Land spreading withdilution (land farming)
Land Spreading with dilution involves mixing of the applied NORM thoroughlywithin the top 8 inch (20.3 cm) layer of soil using agricultural equipment in anarea where NORM was not originally present above background levels.
Non-retrieved line(surface) pipe
Buried line pipe used at a facility could be abandoned in place after beingflushed to remove any oil or gas present.
Burial with unrestrictedsite use
Burial with unrestricted site use involves burial of NORM with at least 15 feet(4.6m) of cover that is level with the surrounding terrain, minimising erosionpotential.
Commercial oil industrywaste facility
Disposal in a commercial oil industry waste facility assumes burial with otheroilfield wastes where NORM represents less than 7% of the total waste volume.
Commercial NORMwaste facility
A NORM waste disposal site is designed to contain NORM for long periodsand its control may revert to a national authority for permanent monitoring and
restricted future use after closure.Commercial low levelradioactive waste facility
A low-level radioactive waste disposal is defined and licensed under nationalregulations with numerous protective features and restrictions.
Plugged and abandonedwell
Well abandonment operations provide an opportunity to dispose of NORM.
Well injection andhydraulic fracturing
Sludge and scale wastes could be injected or fractured into formations that areisolated geologically and mechanically.
Equipment release tosmelter
Smelting may be a viable option for NORM contaminated tubulars and otherequipment.
Once potential disposal options are identied as a result o preliminary selection then a ull assess-ment in terms o risk and cost can be undertaken. Risk assessment has shown that the lowest residual
risk methods or NORM disposal may be underground injection and class one landll.A typical process or the control o NORM waste during shutdown operations is detailed in Figure7..
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Figure 7.1 Control of NORM waste during shutdown operations
Pre T&I survey
Assume NORM
contaminated untilproved otherwise
Enhanced
gamma doserate?
Provide informationon NORM status to
operations
Workers protection &contamination control
measures
Representativesamples
Final NORMdisposal
Interim storage
Transportation incontrolled manner
Normal disposalfor hydrocarbon
waste
NORM aboveaction levels?
Yes
No
YesNo
Hazard exists
ontrolled hazard
afe disposal options
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NORM contaminated equipment must be handled, transported, stored, maintained or disposedin controlled manner. Protocols are required to ensure that equipment is not released or handled
without controls to protect the worker and prevent contamination o the environment. Tereore,
it is critical to understand and control how and where NORM materials can be transported. Forexample, drilling pipe that contains low-level NORM scale can be unrecognised and transported toa variety o secondary pipe reprocessing acilities with subsequent, inadvertent exposure and spreado NORM.
Te ollowing should be considered the minimum requirements or the control o NORM-contam-inated equipment. Equipment should:
Be decontaminated prior to release or unrestricted use
Be stored only in designated storage areas
Be tagged or clearly marked as NORM contaminated.
Be handled only by employees trained in NORM hazards and is using PPE
Not be sent or maintenance/repair to workshops without inorming the workshop that thecomponent is contaminated with NORM.
Be disposed o only in an approved NORM disposal acility.
Be decontaminated only in an approved NORM decontamination acility or according to anapproved decontamination protocol. Once veried as ree rom NORM contamination, theequipment may be :
Re-used
Sent or repair to a workshop prior to being re-used
Sold or disposed o as scrap
Be stored in areas which are exclusively used or the storage o NORM-contaminated equip-
ment.In addition:
All open sections o equipment, ie ange or pipe ends, etc should be adequately covered byheavy-gauge UV-stabilised plastic or other suitable materials to ensure that NORM materialdoes not leak rom the item.
Routine checks on al l stored NORM-contaminated equipment should be undertaken to ensurethat the integrity o the protective measures is adequate. Routine checks should be carried outat least on a quarterly basis.
Detailed and veriable records should be maintained o al l stored NORM contaminated equip-ment.
A typical process or the control o NORM contaminated equipment is detailed in Figure ..
Control o NORM contaminated equipment
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Figure 8.1: Control of NORM contaminated equipment
Routine facilityoperations
Can equipmentbe screened in-
situ?
Potentially NORMcontaminated
equipment
TransportationScreen equipment for
NORM
Screen equipment forNORM
Assume NORMcontaminated
Contain to preventspread of NORM
contamination
NORMcontaminated?
NORMcontaminated?Transportation
Dedicated NORMstorage facility
Contain to preventspread of NORM
contamination
Decontaminationfacility
Normal operation
Equipment verifiedfree of NORMcontamination
Yes
Yes
Yes
No
No
No
ormal operation
azard exists
ontrolled hazard
afe disposal options
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Decontamination o equipment which is NORM-contaminated should be undertaken in a con-trolled manner to ensure worker protection, prevent the spread o NORM contamination, and tominimise the waste arising rom the decontamination process. Simple mechanical/abrasive ie high
pressure water jetting (HPWJ) in conjunction with other mechanical/abrasive methods has beenproven to be the most cost eective and successul. When such methods are used, considerationneeds to be given to the ollowing:
Changing acilities or workers
Operating areas to carry out work
Handling/receiving areas
Strip down areas
Water jetting areas
Liquid re-circulation system
Ventilation system
Control o equipment (administration system)
Inspection o equipment
Monitoring o equipment
Saety related systems.
Where possible, decontamination systems should be automated, as there are signicant industrialsaety hazards associated with hand-jetting activities. Injuries associated with hand-jetting oper-ations can be dicult to treat successully. A well-dened sae system o work is required which
will consider the associated industrial hazards and as a minimum include Kevlar type PPE (boots,aprons, gloves etc).
Mobile decontamination units have been used successully. Tese utilise modied ISO-containers
to provide containment or HPWJ operations, and are tted with drainage systems which directwater used in the HPWJ operation through a series o lters and back to the water jetting system,so the waster is continually re-circulated. Te basic design criteria or a NORM decontaminationacility may include the ollowing:
9.1 Operating criteria
Te unction o a NORM decontamination acility should be to decontaminate NORM contami-nated components. Te acceptance criteria or successul decontamination should be:
All equipment must be visually clear o scale..
All equipment must be ree o detectable radioactive contamination, as per Section (. ie lessthan double background).
9.2 Required operating areas
Main change roomTis will allow access to the radiologically-controlled areas where NORM decontamination willtake place.
9 Decontamination
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Handling areaTis will be or:
checking the inventory/material being sent or decontamination. carrying out radiation surveys o decontaminated equipment.
providing a segregation system to keep incoming dirty items separate or outgoing clean3.items
a quarantine area or items that require urther decontamination..
Strip down areao allow the strip down o components such as valves, wellheads and other components.
Burning bay to allow for oxy-propane cutting, grinding etc of equipmentTis is an area where airborne NORM contamination is may occur and thereore requires total
containment with a HEPA ltered extract ventilation system. Local extract ventilation (ie elephanttrunks) will also be available in the area to control/remove dust/contamination at source. Workerswill be required to wear respiratory protective equipment (RPE) in this area; thereore the supply obreathing air or RPE is required. Te oor and suraces shall be o an impermeable non-ammablesurace capable o withstanding heavy loads.
Water jetting areaTis is an area where airborne NORM contamination may occur and thereore requires total con-tainment with a HEPA-ltered extract ventilation system. In this area, workers will be requiredto wear respiratory protective equipment (RPE) in this area; thereore the supply o breathing airor RPE is required. Te oor and suraces should be o an impermeable non-ammable suracecapable o withstanding heavy loads, and the impact o HPWJ.
Liquid recirculation systemAll process liquid used in decontamination operations should be ltered and re-used. Tere shouldbe no connection to any external drainage system. Te ollowing elements will be required in thesystem:
Primary supply tank.
Filter bank.
Settling tank.3.
Te system needs to separate NORM-contaminated sediment and oily waste material rom theprocess water.
Water rom the HPWJ area will be circulated back to the system by an enclosed and doubly con-tained drainage system.
A leak detection system should be included in the water circulation system.
Te settling tank should be able to be readily accessible and able to have any sediment removed/decanted into waste containers. Te system shall have capacity to allow the transer o water romthe settling tank to another holding tank to allow sediment removal.
9.3 Control o equipment
An administrative system is required to control and track the progress o a ll equipment and compo-
nents entering the decontamination acility.
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9.4 Inspection o equipment
Inspection o all equipment and components should be carried out on receipt. Te status o the
equipment should be logged and any damage not logged on the documentation should immediatelybe brought to the proponents attention and the component shall be quarantined pending urtherinstruction rom the proponent.
9.5 Monitoring o equipment
Monitoring o equipment or clearance should only be carried out by trained operators.
All monitoring equipment should be ully operational and within its calibration period. A check onthe operational status o all radiological monitoring equipment should be maintained.
An administrative system should be implemented to identiy items which are NORM-contami-
nated rom those that have been cleaned.
Figure 9.1: NORM decontamination operations
Personal decontamination should be carried out in a manner which restricts radiation exposure byminimising potential or the inhalation, ingestion and absorption o radioactive materials.
Areas o land which become NORM contaminated should be remediated such that NORM levelsare at or below the criterion described in Section .
Land which is NORM-contaminated as a result o oil and gasrelated operations, such as an evapo-ration pond or land arm, should be remediated prior to release or unrestricted use. Remediation
is the systematic removal o NORM contamination rom the area in a controlled manner, with thecontaminated soil/material becoming part o the NORM waste stream Land remediation requiresclear release criteria to be established. A general schematic or land remediation is detailed in Figure9.. Prior to any remediation operations careul analysis o the overall risks shall be completed toensure that there is benet to be gained by carrying out the operation.
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Figure 9.2 Remediation of NORM contaminated land.
Establish radiologicalsurveillanceprogramme
Establish releasecriteria
Perform radiologicalsurveys
EnhancedNORM
detected?
Collect representativesamples
Assess radiologicalrisks
EnhancedNORM
detected?No
Yes
Above releasecriteria?
No actionrequired
Yes
NoYes
Immediateremediation?
EnhancedNORM
detected?
Establish controls tominimise exposure
until land remediatedEnd of operational life
Develop landremediation &
mapping programe
No
Yes
Release of landfrom control
Packaging,containment andtransportation of
waste
Remediate land Verification montoring
Interim storage ofwaste
Final disposal ofNORM waste
Yes
No
No
Normal operation
Hazard exists
Controlled hazard
Safe disposal options
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Workers entering NORM-contaminated vessels or conducting intrusive work on NORM-contam-inated equipment should adhere to the ollowing guidelines:
Personnel required to work with NORM should be trained in the associated hazards.
All NORM operations shall be covered by a sae system o work which should identiy the haz-ards and highlight the precautions to be taken.
Any item or area with detectable levels o loose NORM contamination should be subject toradiological controls.
Appropriate PPE should be worn (which may include but not be restricted to):
yvek style coveralls
Neoprene, PVC, or NBR gloves
Hal-ace respirators with HEPA cartridges; these should be tested or t
Quarter-ace HEPA disposable respirators.
Eating, drinking, smoking and chewing are not allowed in work areas where there is potential
NORM contamination.
Only essential personnel should be allowed in the work areas o potential NORM contamina-tion.
Personnel should wash up thoroughly with copious quantities o soap and water, aer workingwith contaminated equipment, and beore eating, drinking, or smoking, and at the end o theworkday.
Use systems o work that minimise the generation o waste PPE ( ie use PPE that can be cleaned,inspected and re-used).
Worker protection requirement
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Conned space entry
Personnel should adhere to applicable regulations and guidelines or conned space entry. In addi-tion, beore entering vessels/tanks or other conned spaces known or suspected to be NORM-contaminated, the workers protection measures mentioned in the previous section should be
implemented.
Furthermore, beore entering tanks or vessels in gas plants, especially in propane and methanestreams, vessels/tanks should be emptied and ventilated, through orced ventilation, or at least ourhours prior to entry or cleaning or maintenance. Ventilation will orce any trapped radon gas outo the vessel, while the delayed entry will allow adequate time or the decay o short-lived radondaughters (progeny). It should be noted that radon is not the most signicant hazard associated
with conned space entry and all other loss prevention checks must also be completed. Radon doesnot present an acute hazard to health, and the requirement to vent the tank or hours is a means ominimising potential dose uptake, and as such should be included as part o the ull saety job riskassessment.
All personnel and equipment exiting a vessel should be subjected to a NORM contamination survey.
Personnel or equipment ound to be contaminated should be segregated and decontaminated.
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ransport o NORM contaminated equipment
NORM materials and/or NORM-contaminated components should be transported in exclusive-use vehicles. No other cargo should be carried in the transportation vehicle.
Boats operating oshore and used to transport NORM contaminated material or equipment,should utilise standard transport containers appropriately segregated and marked to house the con-taminated items. NORM-contaminated items that cannot be stored in standard transport contain-ers should be protected in such a manner as to ensure no leak/spillage o NORM material duringtransport.
Beore dispatch o any NORM materials/components, the receiving organisation should be noti-ed.
Te operator o the vehicle (or boat) should be provided with a written contingency plan detailingthe actions to be taken in the event o a reasonably oreseeable emergency.
Te NORM transportation vehicle (or boat) operator should be aware and capable o implementingthe contingency arrangements to be taken in the event o an accident.
Te vehicle carrying NORM material or NORM-contaminated equipment should bear appropriatetransports placard and signage as required by the International Atomic Energy Agency (IAEA).
Organisations should maintain records o all NORM transportation. Tese records should includethe ollowing:
NORM material description (contaminated equipment, scale, sludge, scrapings, etc)
Volume/quantity o NORM material transported
Method o transportation
Destination
Organisation/acility where the NORM waste was generated
Any other relevant inormation.
Te regulations involving the transportation o radioactive material are complex and thereoreadvice should be sought rom a corporate expert on transportation particularly should cross-bordertransportation be required.
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Figure 12.1: Handling, storage and transportation of potentially NORM-contaminated equipment/waste
Routineoperation
Screen/sample
NORM
Potentiallycontaminated
equipment/waste
Worker's protection &contamination control
procedure
Adhere to NORMmaterial
transportationprocedure
Adhere toNORM storage
procedure
Yes
No
Enhanced levelsof NORM?No
Workers protection &contamination control
procedure
Equipmentrequires
transportation?
Yes
NORM transportprocedure
NORM storageprocedure
Equipmentrequiresstorage?
No
Yes
Yes
No
ontrolled hazard
afe disposal options
Documentation/data
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3 Documentation
As a minimum, the support documentation or a NORM management system should include:
Organisational responsibilities
NORM monitoring requirements
Workers protection and training requirements
Requirements to control NORM-contaminated equipment
Requirements to prevent or minimise workplace contamination.
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Glossary o terms
Alpha radiationRadioactive decay by the emission o a high energy charged particle consisting o protons and neutrons (nucleus o helium atom)
Beta radiationRadioactive decay by emission o a negatively charged particle rom the nucleus o an unstableatom (a beta particle has the same mass and charge as an electron)
CarbonateA compound containing the acid radical o the carbonic acid (CO
3group). Bases react with car-
bonic acid to orm carbonates, egCaCO3
calcium carbonate.
Decay seriesA succession o radionuclides each o which is transormed by radioactive decay into the next
member until a stable nuclide is reached. Te rst member is known as the parent and the subse-quent nuclides are the progeny or daughters.
Gamma radiationHigh energy, penetrating electromagnetic radiation (photons) emitted by unstable nuclei.
NORNaturally Occurring Radionuclide, relating to those radionuclides which are present at trace con-centrations in the Earth.
NORMNaturally Occurring Radioactive Material, relating to the material which is enhanced by techno-logical intervention to concentrations above those usual ly ound in nature. It is sometimes reerredto as ENORM (echnologically Enhanced Naturally Occurring Radioactive Material).
SilicatesTe largest group o minerals, o widely dierent and in some cases, extremely complex composi-tion, but all composed o silicon, oxygen, and one or more metals, with or without hydrogen.
SulphatesSalts o sulphuric acid produced when the acid acts on certain metals, metallic oxides, hydroxidesand carbonates. Te acid is dibasic orming two salts; sulphates and bisulphates.
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Radiation units
Becquerel (Bq)Te SI unit o radioactivity. One Bq is equal to one nuclear disintegration per second. Bq is usedas a measure o surace contamination, Bq cm-; as a measure o air activity concentration, Bq m-3;
and as a specic activity per unit mass, Bq g- or Bq kg-.
Curie (Ci)Te old unit o radioactivity, has been replaced by the Becquerel (Bq). One Ci is equal to 3.7Bq.One Bq is equal to 7 pCi.
REM (r)Te old unit o radiation dose equivalent. r is equal to Sv.
Sievert (Sv)Te SI unit o radiation dose equivalent. Occupational radiation dose limits are specied in units
o milliSievert (ie the whole body radiation dose limit or a radiation worker is mSv). In NORMmeasurements, it is usual to measure in the microSievert or nanoSievert range. All measurementso radiation dose-rate are provided as a rate per hour, eg microSieverts per hour (Sv/hr)
Gray (Gy)SI unit or the absorbed (energy) dose. One Gray equals J/kg.
RadTe old unit o radiation dose absorbed (rad). Te SI unit is the Gray (Gy), which is equal to .rad.
Unit conversions
Activity
Curie (Ci) Becquerel (Bq)
27 pCi 1 Bq
1 nCi 37 Bq
27 nCi 1 kBq
1 Ci 37 kBq
27 Ci 1 MBq
1 mCi 37 MBq
27 mCi 1 GBq
1 Ci 37 GBq
27 Ci 1 TBq
1 kCi 37 TBq
Equivalent dose
Rem (r) Sievert
100 r 1 Sv
1 mr 10 Sv
10 mr 100 Sv
100 mr 1 mSv
1 r 10 mSv
5 r 50 mSv
100 r 1 Sv
Unit prefxes
Fractions Multiples
10-3 milli m 103 kilo k
10-6 micro 106 Mega M
10-9
nano n 109
Giga G10-12 pico p 1012 Tera T
10-15 femto f 1015 Peta P
10-18 atto a 1018 Exa E
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Reerences
Further reading
IAEA,Regulatory and management approach or the control o environmental residues containing naturally occurringradioactie material (NORM), IAEA-ECDOC- ().
IAEA,Regulations or the Sae ransport o Radioactie Material, 996 Edition (As Amended 3) No S-R-.
King Abdulaziz City or Science and echnology (KACS), Basic Regulations or Protection Against Ionizing Radia-tion, 997.
Underhill, Philip , Naturally Occurring Radioactie Material, Principles and Practice, St Lucie Press (996), ISBN-57-9-.
Saudi Aramco Engineering Procedure (SAEP-35) Management o echnologically Enhanced Naturally OccurringRadioactie Material (NORM) (5).
Saudi Aramco Radiation Protection Manual ().
SNIFFER, Identifcation and Assessment o Alternatie Disposal Options or Radioactie Oilfeld Wastes, echnicalReports (Project UKRSR7) (/5).
Canadian Guidelines or the Management o Naturally Occurring Radioactie Materials (NORM) , Prepared by the
Canadian NORM Working Group o the, Federal Provincial erritorial, Radiation Protection Committee, First Edi-tion, October .
Louisiana Regulations, itle 33: ENVIRONMENAL QUALIY, Part XV. Radiation Protection, Chapter . Reg-ulation and Licensing o Naturally Occurring Radioactive Materials (NORM).
Georgia State REGULAION AND LICENSING OF NAURALLY-OCCURRING RADIOACIVE MAE-RIALS (NORM), October 99.
EXAS REGULAIONS FOR CONROL OF RADIAION, Part 6 - Licensing o Naturally Occurring Radio-active Material (NORM).
Te Council o the European Union, Council Directive 96/9/EURAOM laying down basic saety standards or theprotection o the health o workers and the general public against the dangers arising om ionizing radiation, 3th May996.
Te Oil Industry International Exploration & Production Forum,Low Specifc Actiity Scale: Origin, reatment andDisposal, Report No6.6/7 January 9.
Burgess PH, Guidance on the Choice, Use and Maintenance o Hand-held Radiation Monitoring Equipment, NRPB-R36, National Radiological Protection Board, May , ISBN 595 67.
Jonkers G, Hartog FA, Knaepen WAI, Lance PFJ,. Characterization o NORM in Oil & Gas Production (E&P) Indus-try, International Symposium on Radiological Problems with Natural Radioactivity in the Non-Nuclear Industry,Amsterdam, Te Netherlands, September 997.
NRPB, NORM in the Oil and Gas Industries, Radiation at Work Series (999)..
IAEA,3. Radiation Protection and the Management o Radioactie Waste in the Oil and Gas Industry, Saety Series No3 (3) ISBN 9--3-7.
IAEA,. Extent o Environmental Contamination by Naturally Occurring Radioactie Material (NORM) and echno-logical Options or Mitigation, echnical Reports Series No 9 (3) ISBN 9--53-.
Bird AF, Rosser HR, Worrall ME, Mously KA, Fageeha OI,5. echnologically Enhanced Naturally Occurring RadioactieMaterial Associated with Sulate Reducing Bacteria Bioflms in Large Seawater Injection System, Society o PetroleumEngineers, Conerence on Health, Saety & Environment in Oil and Gas Exploration and Production, Kuala Lumpur,Malaysia, March 3, SPE 73959.
American Petroleum Institute,6. Bulletin on Management o Naturally Occurring Radioactie Materials (NORM) in Oiland Gas Production, API Bulletin E, Second Edition, April 6.
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What is OGP?
Te International Association o Oil & Gas Producers encompasses the worlds leading privateand state-owned oil & gas companies, their national and regional associations, and majorupstream contractors and suppliers.
Vision
o work on behal o the worlds oil and gas producing companies to promote responsible
and protable operations
Mission
o represent the interests o oil and gas producing companies to international regulators andlegislative bodies
o liaise with other industry associations globally and provide a orum or sharing experiences,debating emerging issues and establishing common ground to promote cooperation,consistency and eectiveness
o acilitate continuous improvement in HSE, CSR, engineering and operations
Objectives
o improve understanding o our industry by being visible, accessible and a reliable sourceo inormation
o represent and advocate industry views by developing eective proposals
o improve the collection, analysis and dissemination o data on HSE perormance
o develop and disseminate best practice in HSE, engineering and operations
o promote CSR awareness and best practice
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