The discovery of oil and gas-related Technologically Enhanced Naturally Occurring Radioactive Material (TENORM) can be a very adverse surprise with important implications to worker safety, divestment and compliance with operational and material-disposal-related matters, in addition to operational routines. The purpose of this presentation is to examine the geochemical behavior of TENORM-forming constituents harnessing the advantages offered by solution equilibria geochemical models in providing estimates as to the potential for and the probable location of TENORM-bearing precipitates, including those consisting of both radium-enriched alkaline earth (dominantly, barium) sulfates and those consisting of Lead-210. The additional complexity posed by the presence of very high ionic strength oil and gas-related production fluids in the geochemical modeling effort will be shown to be addressed through the use of a specially augmented thermodynamic database; one that additionally includes the ability to simulate changes in solution temperature and oxidation/reduction state and how these changes impact the development of radioactive precipitate. The presentation will provide insight as to how these observations can be leveraged to assess hydrocarbon production within the Michigan Basin as to TENORM formation and further how specific State of Michigan TENORM regulations apply to impacted materials.

1. © 2016 ARCADIS2 December 20161
UNDERSTANDING TENORM-RELATED
CHALLENGES ASSOCIATED WITH MICHIGAN
BASIN HYDROCARBON PRODUCTION
Donald J. Carpenter, PG, CPG
December 1, 2016

2. © 2016 ARCADIS2 December 20162 © 2016 ARCADIS2 December 20162
A Systematic Overview will aid in Understanding
TENORM-Related Issues

3. © 2016 ARCADIS2 December 20163
Technologically
Enhanced
Naturally
Occurring
Radioactive
Material is
One of Five
Radioactive
Wastes
Regulated in
the US
High Level Radioactive Wastes1
Uranium Milling Residues2
“Transuranic Wastes” having an atomic
number greater than 92 (Uranium)3
Technology Enhanced Naturally Occurring
Radioactive Material (TENORM) or accelerator
produced materials- Dominantly regulated at
the State Level
4
Low Level Radioactive Waste5
Definition of Radioactive Wastes
Within the United States

4. © 2016 ARCADIS2 December 20164
TENORM Can Pose Important Worker Safety
and Material Handling and Disposal Issues
May be an unexpected and
disruptive finding
Increasing worker-related
litigation
Increasing regulatory scrutiny
Serious implications related to
improper disposal attempts

5. © 2016 ARCADIS2 December 20165
Aluminum Processing Waste
Coal and Coal Ash Waste
Consumer Products
Copper Processing Waste
Drinking Water Treatment Waste
Fertilizer Waste
Geothermal Waste
Gold and Silver Processing Waste
Oil and Gas Processing Waste
Rare Earth Processing Waste
Tin Processing Waste
Titanium Processing Waste
Wastewater Processing Waste
Zircon Processing Waste
Approximately 100 tons of scale
per oil well is generated annually in
the United States.
The average radium concentration
in scale is estimated at 480 pCi/g
Additional information may be found at the U. S. EPA TENORM website
Oil and Gas Processing Waste is Only One of the
Types of TENORM Recognized by the EPA

6. © 2016 ARCADIS2 December 20166
TENORM Related to Oil And Gas Production has
been Known for Decades
TENORM is found in oilfield hydrocarbons1904
TENORM-bearing scale and sludges in pipes and production
equipment
1951
Millions of barrels of petroleum-related
TENORM awaiting disposal
150,000 barrels being generated per
year
American Petroleum Institute suggests
that 1/3 of all producing U.S. oil and gas
wells have elevated radiation

7. © 2016 ARCADIS2 December 20167
Radioactive Radium, Radon, and Lead
are all Generated from Uranium
Present in Host Rock
Unique
Geochemical
Behavior of
each
Radionuclide
must be
considered
Two different forms of TENORM can be
generated:
1) Radium-enriched Barium Sulfate
scale
2) Lead-210 formed from Radon-222
present in natural gas
Important
Gamma
Emitters

8. © 2016 ARCADIS2 December 20168
Radium Isotopes are also
Produced within the Thorium-232
Decay Chain
Important
Gamma
Emitters
• Separation by geochemical
processes of the thorium parent
from the radium daughters
results in rapid deletion due to
their short half-lives
• Only about 6% of initial Ra-228
remains after about 25 years (4
half-lives)
• Ra-228 typically not a concern
at legacy operations, but may be
detectable in “new” material
Gamma
measured
at landfills

9. © 2016 ARCADIS2 December 20169
Predictable Manner of Nuclear Decay Provides
Insight as to Radionuclide Composition with Time
Combined with Specialty
Geochemical Modeling can
Help Predict Formation of
TENORM Scale
 Rate of Formation of Radium from
Known Activity of Uranium
 Rate of Formation of Radon from
Known Activity of Radium
 Rate of Formation of Lead from
Known Activity of Radon
U-238 → Ra-226 → Rn-
222 → Pb-210

10. © 2016 ARCADIS2 December 201610 © 2016 ARCADIS2 December 201610
The low levels of radium present though
preclude the direct precipitation of radium
sulfate or formation of a coherent scale layer
Demonstrate co-precipitation of radium with
alkaline earth metals (barium) is dominant
TENORM formation process
Radium can Precipitate as a Discrete Sulfate Mineral
Ra+2 + SO4
-2 → RaSO4

11. © 2016 ARCADIS2 December 201611
Precipitation of Alkaline
Earth Sulfates can Co-Precipitate Radium
Ba+2 + SO4
-2 → BaSO4
Ba+2 + (Ra+2) + SO4
-2 → Ba(Ra)SO4
Acid Insoluble
Readily Pass TCLP for Barium
Physically Resistant Scale
Dense – Hard to Physically Wash Out
Dominantly Physical versus
Chemical Dispersal - caveat
forthcoming
Addition of Barium Chloride [BaCl2]
(a soluble form of barium) and
Sodium Sulfate [Na2SO4] results in
the removal of dissolved radium
from solution – Proven wastewater
treatment process

12. © 2016 ARCADIS2 December 201612
The Geochemical Behavior of Uranium can help
Explain its Potential Separation from Radium
2 4 6 8 10 12 14
–.5
0
.5
1
pH
Eh(volts)
UO2
++
UO2(CO3)2
--
UO2(CO3)3
----
UO2CO3
Uraninite
25°C
JGillow Fri Jun 15 2007
DiagramUO2
++
,T=25°C,P=1.013bars,a[main]=10
–5.066
,a[H2O]=1,a[HCO3
-
]=10
–3
;Suppressed:U3O8(c,alph),U4O9(c)
• U+4 Oxidation state
(Uraninite [UO2]) is stable under
low Eh conditions (sulfides)
• UO2
+2 oxidation state is stable
under high Eh conditions
(sulfate)
• Uranium may be oxidized and
transported away from radium
which is immobile as a sulfate
• Radium may be mobilized in
sulfate deficient conditions
UO2 and H2S or HS-

13. © 2016 ARCADIS2 December 201613
Radium Accumulation Potential is a Function of
Only a few Factors that can be Readily Modeled
These factors can be readily modeled, yielding an estimate of
Radium-226-related TENORM production
Hot (deep) – High Salt (brine) Content – High Flow
Use of Specialty Pitzer-based Thermodynamic Database and Solution
Equilibria Modeling
Uranium Activity within
Producing Formation
Radium Transfer
Efficiency to Brines
Geothermal Gradient
and Depth of Producing
Formation
Concentration of
Chlorides (Brine
Composition)
Total Flow Rate

14. © 2016 ARCADIS2 December 201614
Assess effects of:
• Cooling
• Sulfide oxidation
(formation of new
sulfate ion)
• Mixing of multiple
solutions
• Reactions with
surface soils and
sediments
• Changing
geochemical
conditions
• Precipitation of
alkaline earth
(barium) sulfates Benefit in proactively understanding likely areas of TENORM
and insight into its radioactivity and optimizing its deposition
Geochemical Modeling can
Identify Locations and Conditions
Leading to TENORM Formation

15. © 2016 ARCADIS2 December 201615
Removal of Sulfate Ion can Lead to Dissolution of
Sulfate Minerals and Release of Radium
Bacterial Reduction of Sulfate Ion Under Reducing Conditions
can Modestly Destabilize Barite or Other Sulfate Minerals
SO4
-2 + 2CH2O ► H2S + HCO3
- Ba(Ra)SO4 + 2CH2O ► Ba+2 + Ra+2 + H2S + HCO3
-

16. © 2016 ARCADIS2 December 201616
How can I have Radioactive Material in my Natural
Gas Plant?

17. © 2016 ARCADIS2 December 201617
Hydrocarbon and Produced Fluids
Radium-226 → Radon-222
Natural Gas Stream
CH4
CH4 CH4
CO2
CH4
CH4
C2H6
C3H8
H2S
Rn-222 Rn-222
Rn-222
CH4
CH4 CH4
CO2
CH4
CH4
C2H6
C3H8
H2S
Rn-222 Rn-222
Rn-222
Lead-210 TENORM Results from Onward Processing
of Produced Fluid and Co-Associated Natural Gas

18. © 2016 ARCADIS2 December 201618
Radioactive Decay of Radon Results in Radioactive
Lead Production and the “Other TENORM”
Radon-222 → Lead-210
CH4
CH4 CH4
CO2
CH4
CH4
C2H6
C3H8
H2S
Rn-222
Natural Gas Stream
Rn-222
Rn-222
Pb-210
Pb-210
Gas stream-entrained Lead-210 particles are now available for deposition
within the processing facility

19. © 2016 ARCADIS2 December 201619 © 2016 ARCADIS2 December 201619
Radon Activity is Highly Concentrated Into Propane
Phase During Gas Fraction Separation
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
Methane "Other Gasses" Propane
37 pCi/L – Rn-222
1,165 pCi/L – Rn-222
Up to a 75% Transfer Efficiency
Lead-210 will tend to be
concentrated in propane
processing portion of plant
Composition of a Typical Natural Gas (by Volume)

20. © 2016 ARCADIS2 December 201620
Lead-210 Accumulation Rate is Function of Only a
few Factors
Radon Concentration in Natural Gas
Deposition Efficiency
Total Flow Rate
Duration Available for Rn-222 Decay
Calculations suggested Radon-222 activity within natural gas of
about 24 pCi/Liter

21. © 2016 ARCADIS2 December 201621
The Comparatively Long Half-life of Lead-210 also
Allows for its Persistence After Plant Shutdown
0
10
20
30
40
50
60
70
80
90
100
0 22 45 67 89 112 134 156 178 201
Pb-210
Years
Percent
Initial Activity Plot of Lead-210 Decay

22. © 2016 ARCADIS2 December 201622
Lead-210 And Polonium-210 Typically Form a Thin
Coating on Pipes and Other Internal Surfaces
Shiny internal surface – may or
may not be readily apparent
Typically only Internal surfaces
Implications as to worker
health and material disposal

23. © 2016 ARCADIS2 December 201623
Highest Lead-210 and Polonium-210 Activities Often
Associated with Grease and Rubber Products

24. © 2016 ARCADIS2 December 201624
Lead-210/Grease/Rubber Relationship may be due to
Proven Radon-222 Concentration In Organics
 Leveraged in radio analytical methods Liquid
Scintillation Cocktails (toluene)
 Ostwald solubility coefficient - 30 to 50 times
greater in organics than in water
 Radon-222 concentrates in grease/rubber then
decays into Lead-210
 Lead-210 metal particles may also physically
adhere to grease surface
 Rubber may develop static electrical charge
helping to attract lead grains
 No adverse neutron generation due to
Polonium-210 alpha emission interaction with
lithium within grease

25. © 2016 ARCADIS2 December 201625
Radiological Threats are Increased when Internal
Surfaces are Exposed
Steel pipe attenuates alpha and beta
radiation
Potential for Bremsstrahlung
radiation from Bismuth-210
Worker safety issues increase from
exposing internal surfaces
• Cutting of pipes
• Dismantlement or disassembly
• Subsequent handling
Generation of airborne Lead-210
and Polonium-210 bearing
particulates, radioactive metal fume,
and aerosols

26. © 2016 ARCADIS2 December 201626
It is Not the “Presence” of Lead-210 That is
Problematic, it is its “Unexpected” Presence
Adverse worker exposure
Halting of scheduled work
Potentially problematic disposal
Significant cost and scheduling-related impacts
With proactive identification Lead-210 simply becomes another
“special waste” issue to be addressed during the course of the project

27. © 2016 ARCADIS2 December 201627
Competing Characteristics of the Michigan Basin
Moderate TENORM Generation Potential
• Evaporites present throughout Devonian and Silurian strata – Highly
elevated brine concentration enhances barium solubility
• Comparatively low geothermal gradient ~10°C per kilometer
(average 22°C per kilometer) – cooler brine temperatures decrease
barium solubility
• Comparatively shallow production – contrast to Texas or Louisiana

28. © 2016 ARCADIS2 December 201628
Breadth of Michigan Basin Hydrocarbon Production
will have Spectrum of TENORM Challenges
• Deeper oil production with warm
and highly saline brines – visible
scale formation – legacy
operations
• Long term gas production from
deeper, saline horizons although
less impacted by geology
• Flow rate and duration of
operation
• Gas Processing with propane or
propylene production

29. © 2016 ARCADIS2 December 201629
Michigan is One of 18 States to Specifically Regulate
TENORM
As expected regulations varying significantly by State, both by isotope
and by associated activities
Important to differentiate “remediation” with “disposal” criteria
Remediation Goal (plus background)
5 pCi/g Radium-226
15 pCi/g Radium-226
15 pCi/g Radium-226
15 pCi/g Radium-226
15 pCi/g Radium-226
15 centimeter
lifts

30. © 2016 ARCADIS2 December 201630
Landfill Waste Acceptance Criteria for TENORM
Disposal is Comparatively Higher In Michigan
• Michigan standard – 50 pCi/g Radium-226
• Lead-210 is not explicitly regulated
• Established to help minimize disposal costs
• Higher activities may be disposed by deep well injection
- (Approved by State or EPA)
• Many states’ disposal criteria range from 5 to 30 pCi/g Radium-226
• May include Radium-228, Uranium-238, Thorium-232, Lead-210
• Varying degrees of radiological sophistication of various state
regulators
• Regulations may pertain to medical-related radiopharmaceuticals

31. © 2016 ARCADIS2 December 201631
A Comparatively Limited Suite of Disposal Options
is Available for more Elevated Activity TENORM

32. © 2016 ARCADIS2 December 201632
Careful
Coordination
with Landfills is
Recommended
Whenever
Disposing of
TENORM
Although exempt K-40 and certain Th-232
decay chain products all have gamma
emissions
Portal monitors set to trigger alarm at very
low activities (1.5 to 2 times background)
In event of alarm, you are “presumed guilty
until proven to be slightly less guilty”
May not be aware of the materials that are
acceptable
“Fear Factor” in terms of disposing of
unacceptable material
Communication and “education” in terms of
waste acceptance criteria

33. © 2016 ARCADIS2 December 201633
A Systematic Overview will aid in Understanding
TENORM-Related Issues
Technology Enhanced Naturally Occurring Radioactive Material is One of
Five Radioactive Wastes Regulated in the US
TENORM can Pose Important Worker Safety and Material Handling and
Disposal Issues
Radium Accumulation Potential is a Function of Only a Few Factors that
can be Readily Modeled
It is not the “Presence” of Lead-210 that is Problematic, it is its
“Unexpected” Presence
Careful Coordination with Landfills is Recommended Whenever Disposing
of TENORM

34. © 2016 ARCADIS2 December 201634
Thank you!
c 810 224 2159
e donald.carpenter@arcadis.com
a 28550 Cabot Drive
Suite 500
Novi, MI 48377
DONALD J. CARPENTER
Senior Vice President & Chief Geochemist
Registered and Certified Professional Geologist
AIPG, AK, IN, PA, WI
Connect with me on LinkedIn
Follow me on Twitter @DonCarpenter14

35. © 2016 ARCADIS2 December 201635
Arcadis.
Improving quality of life.