“cradle to grave” - nucleus · 2019. 10. 17. · 214. pb. 214. pb. 27 m β, ... 169: 1. data...

“Cradle to Grave” NORM Management Workshop

September 22, 2019

Section 2.0NORM Characterization

SECTION 2.0NORM CHARACTERIZATION

Presented by: Alex Lopez, CHPAndrew Lombardo, CHP

Perma-Fix Environmental Services Inc.

[email protected]@perma-fix.com

mailto:[email protected]


SECTION 2.0 NORM CHARACTERIZATIONOUTLINE

1. Developing Objectives of Characterization2. Survey Media and Measurements

Solids, liquids and gasInstrumentation – appropriate sensitivity, calibrationAnalytical Analyses

3. Interpretation of Data/Calculations4. Lessons Learned Characterizing NORM in the Oil and Gas Industry

Section 2.1Developing Objectives of

Characterization


1. What are the primary objectives of planned characterization?

2. What are the secondary objectives?

To develop objectives you must compile a list ofparameters needed to plan for the wastecharacterization, safety and risk assessment and/orother data needs:

54Developing Objectives of Characterization(continued)

1. Identify areas/materials with gross activity and/or activity concentration > background

2. Identify the radionuclides present

3. Identify the relative activity of the radionuclides present

Evaluation of the status of secular equilibrium of the uranium and thorium natural decay series and/or subseries is critical


7

238U 238U 4.5 × 109 y α 232Th 232Th 1.4 × 1010 y α234Th 234Th 24.0 d β, γ 228Ra 228Ra 5.7 y β

234mPa 234mPa 1.2 m β, γ 228Ac 228Ac 6.1 h β, γ234U 234U 2.5 × 105 y α, γ 228Th 228Th 1.9 y α, γ

230Th 230Th 7.7 ×104 y α, γ 224Ra 224Ra 3.7 d α, γ226Ra 226Ra 1.6 × 103 y α, γ 220Rn 220Rn 55.6 s α222Rn 222Rn 3.83 d α 216Po 216Po 0.15 s α218Po 218Po 3.1 m α 212Pb 212Pb 10.6 h β, γ214Pb 214Pb 27 m β, γ 212Bi 212Bi 61 m α, β, γ214Bi 214Bi 20 m β, γ 212Po 212Po 3 × 10- 7 s α214Po 214Po 1.6 × 10-4 s α, γ 208Tl 208Tl 3.1 m β, γ210Pb 210Pb 22.3 y β, γ 208Pb 208Pb Stable none210Bi 210Bi 5.01 d β210Po 210Po 138 d α206Pb 206Pb Stable none

Drill Cuttings

Drill Cuttings Thorium Decay SeriesUranium Decay Series

Developing Objectives of Characterization(continued)

8

238U 4.5 × 109 y α Fluids 232Th 1.4 × 1010 y α234Th 24.0 d β, γ 228Ra 228Ra 5.7 y β234mPa 1.2 m β, γ 228Ac 228Ac 6.1 h β, γ234U 2.5 × 105 y α, γ 228Th 228Th 1.9 y α, γ

Fluids 230Th 7.7 ×104 y α, γ 224Ra 224Ra 3.7 d α, γ226Ra 226Ra 1.6 × 103 y α, γ 220Rn 220Rn 55.6 s α222Rn 222Rn 3.83 d α 216Po 216Po 0.15 s α218Po 218Po 3.1 m α 212Pb 212Pb 10.6 h β, γ214Pb 214Pb 27 m β, γ 212Bi 212Bi 61 m α, β, γ214Bi 214Bi 20 m β, γ 212Po 212Po 3 × 10- 7 s α214Po 214Po 1.6 × 10-4 s α, γ 208Tl 208Tl 3.1 m β, γ210Pb 210Pb 22.3 y β, γ 208Pb 208Pb Stable none210Bi 210Bi 5.01 d β210Po 210Po 138 d α206Pb 206Pb Stable none

Thorium Decay SeriesUranium Decay Series


9

238U 4.5 × 109 y α 232Th 1.4 × 1010 y α234Th 24.0 d β, γ 228Ra 5.7 y β234mPa 1.2 m β, γ 228Ac 6.1 h β, γ234U 2.5 × 105 y α, γ 228Th 1.9 y α, γ230Th 7.7 ×104 y α, γ Gas 224Ra 3.7 d α, γ

Gas 226Ra 1.6 × 103 y α, γ 220Rn 220Rn 55.6 s α222Rn 222Rn 3.83 d α 216Po 216Po 0.15 s α218Po 218Po 3.1 m α 212Pb 212Pb 10.6 h β, γ214Pb 214Pb 27 m β, γ 212Bi 212Bi 61 m α, β, γ214Bi 214Bi 20 m β, γ 212Po 212Po 3 × 10- 7 s α214Po 214Po 1.6 × 10-4 s α, γ 208Tl 208Tl 3.1 m β, γ210Pb 210Pb 22.3 y β, γ 208Pb 208Pb Stable none210Bi 210Bi 5.01 d β210Po 210Po 138 d α206Pb 206Pb Stable none

Thorium Decay SeriesUranium Decay Series


6. Identify other hazardous constituents present (may result in a mixed-waste classification)

• Asbestos

• Lead (paint for example)

• PCBs


7. Identify the depth of soil contamination

• Surface 0-15 cm (0 – 6 inches)

• Subsurface below 15 cm (6 inches)

• In contact with groundwater?

• Depth to groundwater

8. Is groundwater sampling appropriate?

9. Is surface water sampling appropriate?


10. Is structural contamination present?

• Total Alpha (fixed + removable)

• Total Beta (fixed + removable)

• Removable Alpha / Removable Beta

• Surface only or at depth

• Are there layers of materials covering surface contamination?

11. How many types of surfaces materials are present?

12. What is the density of the structural material?


13.What levels of NORM are present in areas, bulk materials and structural material?

• Background alpha count rate

• Background beta/gamma count rate

• Background gamma exposure rates

• Background radon concentrations


14.To support a dose assessment to derive volumetric acceptance criteria, identify key site specific input parameters

• Cover depth (if any)

• Depth of Contamination Zone

• Depth of unsaturated zone (between contamination and saturated zone)

• Depth of saturated zone

• Soil type of each zone


15. To support a dose assessment to derive structural surface acceptance criteria, identify key site specific input parameters

• Material types

• How many surfaces (floor, walls, ceiling) exposed to at one time

• Dimensions of surfaces

• Ventilation

• Number of rooms


Section 2.2Survey Media and Measurements


Section 2.2Survey Media and Measurements

1. Surface Soil

2. Subsurface Soil

3. Groundwater

4. Structure Surfaces

5. Radon Gas

96

1. Typically defined as the top 0-15 cm layer of soil

2. Field screening methods include gamma walk-over and drive-over surveys and soil sampling

3. Field screening detection equipment includes global positioning system (GPS) assisted gamma scintillation detection systems

4. Analytical methods include alpha and gamma spectroscopy to identify specific radionuclide concentrations

97Survey Media: Surface Soil

98GPS Drive-over Survey

1. Defined as all soils >15 cm below ground surface (requires auger or drill rig support)

2. Field screening methods include down-hole gamma logging, ex-situ core scanning, and soil sampling

3. Field screening detection equipment may include small diameter gamma scintillation detectors

4. Analytical methods include alpha and gamma spectroscopy

99Survey Media: Sub-Surface Soil

Direct Push Core Sampling

100Sub-Surface Soil Sampling

Core Scanning

Core Sample

Detector

Down-Hole ɤ Logging

8 cm

Bore Hole

101

Gross Gamma Survey

NaI

Detector Geometry

102

1. Defined as subsurface water normally found in aquifers

2. Screening for groundwater involves well installations and water sampling

3. Analytical methods include alpha and gamma spectroscopy

103Survey Media: Groundwater

1. Defined as the interior and exterior walls, floors, ceilings, and rooftops

2. Screening methods include a combination alpha, beta, and gamma scanning techniques and swipe sampling

3. Field screening detection equipment includes a combination of gas proportional and alpha/beta/gamma scintillation detectors

4. Analytical methods include gross alpha/beta proportional counting, alpha and gamma spectroscopy, and Low energy Beta Liquid Scintillation

104Survey Media: Structural Surfaces

Structural Surface Characterization Results

• Gamma radiation exposure rate surveys using a Bicron Micro-Rem Meter or Ludlum Model 19.

• Gross gamma radioactivity surveys using a Ludlum Model 44-10 NaI detector.

• Total α and β surface radioactivity using a direct frisk Ludlum Model 43-89 detector and/or a Ludlum Model 44-93 and cpm results converted to units of disintegrations per minute per 100 square centimeters (dpm/100 cm2) of surface area surveyed.

• Removable α and β surface radioactivity by sample collection with smears. Smears are counted on a Ludlum 2929 with a Model 43-10-1 portable scaler/ratemeter and detector. Count results are converted to units of dpm/100 cm2 of surface area smeared.

Examples of Routine Characterization Surveys:

• Gamma Spectroscopy

The science of identification and/or quantification of radionuclides by analysis of the gamma-ray energy spectrum produced. It is a widely used technique for:

• Environmental Radioactivity Monitoring• Health Physics Personnel Monitoring• Nuclear Materials Safeguards and Homeland Security• Forensics and Nuclear Forensics• Materials Testing• Geology and Minerology• Nuclear Medicine and Radiopharmaceuticals• Industrial Process Monitoring

Measurements- Analytical Analyses

Common NORM radionuclides identified or inferred using gamma spectroscopy:

Measurements- Analytical Analyses(continued)

Radionuclide Gamma Energy [keV] Direct or InferredRa-226 186 DirectRa-228 911 Inferred (Ac-228)U-235 143 DirectAc-228 911 DirectTh-232 911 Inferred (Ac-228)U-238 63.3 Inferred (Th-234)Pb-212 238 DirectPb-214 351 DirectBi-212 727 DirectBi-214 609 DirectK-40 1,460 Direct

Alpha Spectroscopy- used to identify and quantify radionuclides based on alpha particles using the energy spectra (similar to gamma spectroscopy). Common NORM radionuclides identified using alpha spectroscopy are the radionuclides in the uranium and thorium decay series:

Isotopic Uranium: Isotopic Thorium:

• U-238 Th-232• U-235 Th-230• U-234 Th-228

Measurements- Analytical Analyses(continued)

1. Natural:• Uranium series

• Radon• Thorium series• K-40• Tritium

2. Man Added:• Fallout – Chernobyl, Fukushima, weapons testing

110Background Radionuclides

• Radon is the #1 NORM contributor to annual dose

• Radon Quantification (in air)• Common Methods: Low costs, easy analysis

• Alpha Track Detectors• Activated Charcoal Adsorption Device

• Continuous radon monitors• In most cases, radon mitigation is effective

Background Radionuclides: Radon, Rn

• Radiological Properties• Rn-222 is a decay progeny in the U-238 series

• The only gaseous radionuclide in the U-238 decay series• More readily travels with the gas stream than its non-

gaseous parent and progeny radionuclides• Transportation of the radon-containing natural gas results

in a build-up of thin radioactive film layers of the radon progeny that have decayed during transportation

• Thin film composed of the longer-lived Pb-210 and Po-210• Commonly goes unidentified because their radiation

emissions require alpha and low-energy beta detectors• Lack of identification can present added worker exposure

risk

Background Radionuclides: Radon, Rn(continued)

Section 2.3Data Management and Review


1. Data Quality Assessment

2. Reviewing Data – result, uncertainty, MDC

3. Reviewing Data – plotting data, identify trends

4. Determine the Need for Additional Action/Surveys

5. Final Reports

169Data Management and Review

1. Data Quality Assessment:• A scientific and statistical evaluation that determines if

the data are of the right type, quality, and quantity to support their intended use

170Data Management and Review(continued)

2. Reviewing Data – result, uncertainty, MDC:• Conduct a preliminary data review

• Ensure appropriate MDCs have been achieved based on relevant criteria

• Evaluate data measurement uncertainties

• Low activity concentration gamma spec results may have high reported uncertainty

• Some positive results above MDC are better than others


3. Reviewing Data – plotting data, identify trends• Learn about the structure of the data

• Identify patterns

• Identify relationships

• Identify potential anomalies


4. Determine the Need for Additional Action/Surveys:• Draw conclusions from the data

• Tables describe examples of circumstances leading to specific conclusions based on a simple examination of the data


Section 2.4Lessons Learned


Lessons Learned Characterizing NORM in the O&G Industry:

1. Estimating Ra-226 activity from gamma surveys.2. Radon in natural gas tanks (gamma shine).3. Radon progeny particulate plate out in gas facility pipes.

Secular Equilibrium: Occurs when the half-life of the parentradionuclide is much longer than the progeny resulting in equalconcentrations between the parent and progeny after arelatively short period of time.

Understanding the secular equilibrium relationships in theuranium and thorium decay series are key in O&G industry (andmost industries impacted by NORM)

Lessons Learned

Lessons Learned

Ra-226 progeny ingrowth

• The Ra-226 decay series includes the long livedRa-226 parent (1600 year half-life) and severalshort-lived progeny beginning with radon gas.

• Two of the progeny emit high energy gamma (Bi-214 and Pb-214) resulting in a significantly highergamma rate when they are in equilibrium with Ra-226.

• When Ra-226 is separated from the uraniumdecay series (by chemical processes, e.g.dissolution or precipitation) the short-livedprogeny immediately begin “growing back” intoequilibrium with Ra-226.

Lessons Learned: Ra-226 from Gamma Surveys

Radionuclide Half-Life

226Ra 1600 y

222Rn 3.83 d

218Po 3.1 m

214Pb 27 m

214Bi 20 m

214Po 1.6 × 10-4 s

210Pb 22.3 y

210Bi 5.01 d

210Po 138 d

206Pb Stable

• In Pennsylvania, current landfill protocol for disposing ofNORM impacted material is contingent on gammameasurements of the container, e.g. truck portal monitors atlandfill entry.

• The problem is accurate measurement of gamma radiationduring the ingrowth of Ra-226 and gamma emitting progenyin wastewater sludge.

• Estimation of the Ra-226 activity concentration (pCi/g)based on gamma measurements on the outside of containerscan be off by a factor of 4.

Lessons Learned: Ra-226 from Gamma Surveys(continued)


238U 4.5 × 109 y α234Th 24.0 d β, γ234mPa 1.2 m β, γ234U 2.5 × 105 y α, γ

Fluids 230Th 7.7 ×104 y α, γ226Ra 226Ra 1.6 × 103 y α, γ

222Rn 3.83 d α218Po 3.1 m α214Pb 27 m β, γ214Bi 20 m β, γ214Po 1.6 × 10-4 s α, γ210Pb 22.3 y β, γ210Bi 5.01 d β210Po 138 d α206Pb Stable none

Uranium Decay Series

238U 4.5 × 109 y α234Th 24.0 d β, γ234mPa 1.2 m β, γ234U 2.5 × 105 y α, γ

Fluids 230Th 7.7 ×104 y α, γ226Ra 226Ra 1.6 × 103 y α, γ222Rn 222Rn 3.83 d α218Po 218Po 3.1 m α214Pb 214Pb 27 m β, γ214Bi 214Bi 20 m β, γ214Po 214Po 1.6 × 10-4 s α, γ210Pb 210Pb 22.3 y β, γ210Bi 210Bi 5.01 d β210Po 210Po 138 d α206Pb 206Pb Stable none

Uranium Decay SeriesRa-226 progeny ingrowth

• When O&G wastewater sludge is produced, the progenyof radium haven’t had time to equilibrate, and much ofthe radon gas is driven out of the solid matrix.

• Radon immediately begins growing back intoequilibrium with Ra-226 parent.

• In 2 weeks the gamma output due to radon progenyingrowth is at least twice as high as time zero when thesludge is produced.

• Fresh sludge measured with gamma detector at landfillresults in a non-conservative estimate of Ra-226activity.

Theoretical In-Growth Curve


Ra-226 Progeny Ingrowth – Sludge Sample Curve


Lessons Learned: Rn-222 in Natural Gas

Rn-222 progeny ingrowth• Radon more readily travels with the gas

stream than its non-gaseous parent andprogeny radionuclides

• Transportation of the radon-containingnatural gas results in a build-up of thinradioactive film layers of the radonprogeny that have decayed duringtransportation

• Thin film composed of the longer-livedPb-210 and Po-210

238U 4.5 × 109 y α234Th 24.0 d β, γ234mPa 1.2 m β, γ234U 2.5 × 105 y α, γ230Th 7.7 ×104 y α, γ

Gas 226Ra 1.6 × 103 y α, γ222Rn 222Rn 3.83 d α

218Po 3.1 m α214Pb 27 m β, γ214Bi 20 m β, γ214Po 1.6 × 10-4 s α, γ210Pb 22.3 y β, γ210Bi 5.01 d β210Po 138 d α206Pb Stable none


238U 4.5 × 109 y α234Th 24.0 d β, γ234mPa 1.2 m β, γ234U 2.5 × 105 y α, γ230Th 7.7 ×104 y α, γ

Gas 226Ra 1.6 × 103 y α, γ222Rn 222Rn 3.83 d α218Po 218Po 3.1 m α214Pb 214Pb 27 m β, γ214Bi 214Bi 20 m β, γ214Po 214Po 1.6 × 10-4 s α, γ210Pb 210Pb 22.3 y β, γ210Bi 210Bi 5.01 d β210Po 210Po 138 d α206Pb 206Pb Stable none


Radon Progeny Plate-Out

• When natural gas comingled with radon gas is flowingthrough piping in gas processing facilities, Rn-222 is inequilibrium with its progeny (particulates).

• A small fraction of the particulates plate-out inside elbows ofthe pipes, resulting in relatively high gamma exposure rateswhen gas is flowing.

• When the flow of fresh radon stops the two gamma emittingprogeny quickly decay away.

Lessons Learned : Rn-222 in Natural Gas(continued)

Radon Progeny Plate-Out

• However, two of the particulate progeny are relatively long-lived (Pb-210 and Po-210) and remain inside the pipes afterthe flow of gas ceases.

• Pb-210 emits beta radiation and has a half-life of 22 years.

• Po-210 emits alpha radiation and has a half-life of 140 days.

• When pipes are opened or when filters are changed out thereis potential for internal exposure to the alpha and betacontamination.


• Perma-Fix has consulted to trucking companies who haverefitted their fleet with natural gas tanks.

• The trucks now alarm nearly every time they pass throughportal monitors due to the radon progeny within the gastanks, making it difficult to clear the truck contents forradioactivity

• “Filtering” radon comingled with natural gas is not easy sinceradon and methane react the same to traditional carbonactivated filtration of radon.

Lessons Learned: Rn-222 in Natural Gas(continued)

• Gas Fractionation / Processing Facilities• Radon has a similar pressure and temperature curve

to propane• Processing / fractionation facilities separate out

propane based on boiling point• Radon preferentially flows with propane


Questions?

Alex Lopez, [email protected]

Andrew J. Lombardo, [email protected]

www.perma-fix.com/norm.aspx



http://www.perma-fix.com/norm.aspx

“cradle to grave” - nucleus · 2019. 10. 17. · 214. pb. 214. pb. 27 m β, ... 169: 1. data...

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