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SLAC RadioanalysisLaboratoryHenry Brogonia
Dosimetry and Radiological Protection Group (DREP)
DOE Environmental Radiation Protection Program Review (July 23-24, 2007)
2
Radioanalysis Laboratory Mission
“To provide high quality, accurate, and timely radiological analysis to SLAC
customers and to support SLAC mission and operations.”
3
Radioanalysis Laboratory Services
– Measurements to support the radiological environmental protection program, e.g.,
• characterizing tritium and other radionuclides in environmental samples,
• providing radiological information for sanitary sewer discharges, facility clean-up and decommissioning
– Measurements of radionuclides in SLAC accelerator cooling systems
– Measurements of radionuclides in samples for the Field Operations Group
– Characterizing radioactive waste for the Radioactive Waste Group
4
Main isotopes at SLAC
Radionuclide Material Method of Detection
H-3 (low energy beta) Water Liquid Scintillation Counting
Be-7 Water, Soil Gamma Spectroscopy
Na-22, Co-60, Mn-54, Co-57 Soil and Metals Gamma Spectroscopy
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Sample profile (1995-2007)Sample Type Number CustomerGround Water 1491 EPDStorm Water 301 EPDWaste Water 3155 CEFOther Water 948 RPD, CEFOther Liquid 1000 RPD, CEF
Oil 77 RPDResin 465 CEF
Air Sample 8 RPDSoil 526 RPD
Concrete 213 RPDSwipe 669 RPD
Miscellaneous 724 RPDTotal 9577 ----------
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Laboratory Layout
LSC Laboratory Area housing two LSC machines, sample storage cabinets and preparation area.
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Laboratory Layout
Gamma Spectroscopy Counting Room housing two HPGe systems with lead caves for low background counting
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Equipment Inventory
Instrument Name Instrument Type Software Radiation monitored
Packard Tri-Carb1900TR
Liquid Scintillation Counter Packard Tri Carb LiquidScintillation Analyzer
(MS-DOS)
H-3
Packard Tri-Carb 3100 Liquid Scintillation Counter Quantasmart Version 2.02 H-3
ORTEC GEMX HPGe (50%)
n-type, Low Background HPGe Gammavision Version 6.01 Gamma emittingnuclides
ORTEC GEM HPGe (40%)
p-type, Low Background HPGe Gammavision Version 6.01 Gamma emittingnuclides
ORTEC Transpec Portable HPGe Gammavision Version 6.01 Gamma emittingnuclides
BNC SAM Portable Sodium Iodide BNC Software Version 2.11.01
Gamma emittingnuclides
Hach Microdistillation Distillation equipment N/A N/A
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Sample Analysis
Sample requires LSC?
Sample requires Gamma Spec?
Perform LSC analysis for H-3
Perform Gamma Spectroscopy
Enter sample results into database
Release results to customer
Obtain approvals
Results make sense?
Review sample analysis and QA/QC
results
Reanalyze Sample?
Start:Receive sample and Sample Information Sheet. Sign Chain of
Custody
End:Dispose of
Sample
Yes
NoNo
Yes
Yes
Yes
No
No
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Customer SIS SLAC Environmental SAMPLE ID#: L14890 Date Taken:______________________________________________________
System/ Description _______________________________________ _____________________________________________________________ Taken By:________________________________________
Mail Stop ______Ext:_______________________________
_
To request analysis a Sample Information Sheet (SIS) is filled out and a sample label is attached to the container by the customer.
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COC Log
The chain of custody (COC) log is signed by the customer and the operator when the sample is relinquished to the Lab.
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Analysis DeterminationFor Liquid Scintillation:
– All liquids– H-3 swipes
For Gamma Spectroscopy:– Positive channel C result from LSC (this channel monitors for
any beta/gamma emitters other than H-3)– Any sample from waste water systems with historically positive
gamma results (i.e., LCW from BDE and HX collimator)– Groundwater wells with positive H-3 results– Radiological-guarding groundwater wells– Oil
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LSC Preparation and Counting• Samples are prepared in 20 ml plastic vials
– 5 ml sample– 15 ml cocktail (Ultima Gold)
• A Background and two Standard vials are counted with each batch
14
LSC Analysis & Software
• Background subtraction• 3 counting windows
– Channel A, 0-18.6 keV– Channel B, 2-18.6 keV– Channel C 18.6-2000 keV
• Results are printed out• Additional Software features
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LSC Software
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LSC H-3 Analysis
• Two protocols– LCW (30 min): LCW, Wastewater, Swipes, Oil,
etc.– Environmental (150 min): Storm water,
Groundwater
Protocol # Count Time(min)
Type ofSample
Counted
MDA(pCi/L)
1 30 LCW, oil,swipes
1000
13 150 Environmentalwater
500
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HPGe Gamma Spectroscopy
Three counting protocols:
Protocol Name Count time (sec) Type of Samplecounted
Liquid 1000 Water, Oil, Resin, Slurry
Soil 1000 Solids
Disk 1000 Air Filters, swipes
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Gammavision
• Windows based software• Sample Description File (SDF)
– Customizable analysis parameters• Calibration Files• Libraries• Job Files (Macros)• Spectrum stripping is available• Reprocess
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HPGe MDA
Radionuclide Liquid MDA for water (pCi/L)
Soil MDA for soil (pCi/g)
Be-7 1784 2.61
Co-60 270 0.52
Co-57 180 0.32
Mn-54 246 0.31
Na-22 95 0.12
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Results
• Results are entered into an Access database– Backed up daily– Relational database– Results must be approved by the Radioanalysis
manager prior to release
• Paperwork is copied and archived
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Data Entry
22
Data Entry
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Rad Lab QA/QCThe Radioanalysis Laboratory has implemented thefollowing QA/QC:
• Daily source check and background check prior to use• Batch QC (for LSC)• Annual calibrations or after major system repair/upgrade• Mixed Analyte Performance Evaluation Program
(MAPEP) participation (semiannual)• For questionable samples, additional QA/QC process
such as spiking, split samples for outside independent analysis may be performed
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Daily QA
Daily QA performed prior to use
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Daily QA
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Calibrations
Calibrations performed annually , or after major repair/upgrade
27
MAPEP
Mixed Analyte Performance Evaluation Program– Water and Soil Samples sent to SLAC
(semiannual)– Samples counted as field samples
• Water distilled prior to H-3 analysis• For Gamma Spec, water and soil transferred to 500 ml
Nalgene bottle– Results are checked against reference
28
Nuclide% Bias for
Water% Bias for
Soil
H-3 (LSC) -1.4 N/A
Cs-137 4.9 2.4
Co-57 -1.2 2.3
Co-60 7.8 0.8
Mn-54 4.2 -0.5
Zn-65 -1.6 -3.3
MAPEP Results for Series 17 (2007) for both LSC and Gamma
29
Sample StorageSamples are stored in seismic proof cabinets
(1 year max)
30
Sample Disposal
31
Summary
• The laboratory has the necessary equipment to support SLAC operations
• Laboratory personnel are well trained• The program and counting process are
documented• The counting protocols meet EPA 906.0• Established QA/QC program