TENORM Analytical Measurements
Dennis J. Leeke
May 12, 2014
Radiochemistry Definitions
Alpha: Helium nucleus
Beta: Electron/positron particle
Gamma: Photons
Decay: Release of and alpha or beta particle
Secular equilibrium: Parent = decay progeny
MDC: Minimum detectable concentration
In-growth: Time to allow decay progeny to be
formed or secular equilibrium reached
Radiochemistry Differences
• MDC calculated by sample
– Dependent on volume, matrix, activity, and time
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Methods less defined
Certifications less mature
Solids not historically addressed
TAT Limitations
Analytical Considerations for Disposal
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One size does not fit all
Lack of statutory authority
Changing landscape
Cradle to grave?
Local regs/permits
Dose/screening vs activity
Techniques
• GAB Screen (900.0, 9310)
– Cost vs. TDS Limitation
• GAB Co‐precip (SM7110C)
– Robust vs. Cost
• Radiochemical (903.1, 904.0, 9315, 9320)
– MDC & speed vs. matrix effects
• Gamma Spec (901.1)
– Selectivity vs. sensitivity & speed?
Turnaround Time Limitations
Radium-226/Radium-228 (solid) – 4 weeks.
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21 day in growth period required to allow for secular
equilibrium with Ra-222
Radium-226 (water) – 1 week (must allow for Radon buildup)
Radium-228 (water) – 1 week (must allow for Ac-228 buildup)
Gross Alpha/Beta – 5 days (must be stored for 3 days)
THESE ARE MINIMUMS, TAT MAY BE INVERSELY
PROPORTIONAL TO MDC REQUIREMENTS
Shale Related Challenges
• Dissolved solids
– 100 mg limit for 900.0
• Barium tracer for Radium
– Use Ba‐133
• Highly variable activities & end uses
• Incomplete solubility of solids?
Recommendations
• Be descriptive on the matrix
– Produced water, private well water, flowback water: not water
• Communicate MDC requirements
– Frac related not equivalent to pre‐drill
Recommendations
• Discuss method options
– GA Co‐precipitation SM7110C
– Tracer used for Radium
– Gamma spec for solids, concentrated waters
• Understand TAT Limitations
– Rapid option for Ra‐226 gamma spec
“Rapid” Ra‐226
U/Th Decay Chains
Radium‐226
• Creates a potential bottleneck
• Normal TAT 3‐4 weeks for solids
• Limitation of the current method
– Requires 21 day “in‐growth”
• We may have a solution!
Ra‐226: 186.1 keV
U‐235: 185.7 keV
Ra‐226 + U‐235
Direct v Ingrowth TENORM
300
250
200
150
100
50
0
12/7/2012
12/5/2012
12/3/2012
12/1/2012
11/29/2012
11/27/2012
11/25/2012
11/23/2012
11/21/2012
11/19/2012
11/17/2012
11/15/2012
Pb‐214/Bi‐214 Ingrowth
Ra‐226 Mean
Pb‐214/Bi‐214
Ra‐226
Direct v. Ingrowth NORM
8
7
6
5
4
3
2
1
0
Poly. (Pb‐214/Bi‐214)
8/19/2013
Mean
8/14/2013
Ra‐226
8/9/2013
8/4/2013
7/30/2013
7/25/2013
7/20/2013
Pb‐214/Bi‐214
THANK YOU!
[email protected]