ML12090A687
| ML12090A687 | |
| Person / Time | |
|---|---|
| Site: | Indian Point  |
| Issue date: | 07/14/2008 |
| From: | Edington G, Holt-Larese K, O'Neill M, Mallecia Sutton Cellular Bioengineering, Lawrence Livermore National Lab (LLNL), Sandia |
| To: | Atomic Safety and Licensing Board Panel |
| SECY RAS | |
| Shared Package | |
| ML12090A683 | List: |
| References | |
| RAS 22152, 50-247-LR, 50-286-LR, ASLBP 07-858-03-LR-BD01 | |
| Download: ML12090A687 (12) | |
Text
NRC000052 Submitted: March 30, 2012 Decontamination of Cs-137, Pu-239, and Am-241 from Hard Surfaces using a Peelable Polymer-based Hydrogel G. J. Edgington1, M. P. ONeill1, and K.C. Holt-Larese2 Additional work by M. Sutton3, R. P. Fischer3, and M. M. Thoet3 1 Cellular Bioengineering, Inc. (CBI), Honolulu, HI 2 Sandia National Laboratories, Albuquerque, NM 3 Lawrence Livermore National Laboratory (LLNL), Livermore, CA 2008 HPS Annual Meeting Pittsburgh, PA MPM-D.7 07/14/08
Decon Gel 1101 - What is It?
Apply Dry Peel
- Near neutral-pH, low-odor polymer hydrogel
- Utilizes surfactants to lift contaminants
- Soluble chelators bind contaminants for transport
- Contaminants pulled into polymer upon drying
- Entrapped in rehydratable polymer matrix
October 2007 - Coupon Initial Activity after Activity after December 2007 -
Name Activity 1st Decon 2nd Decon (Ci) (Ci) (Ci)
CBI commissioned efficacy
- Sandia applied 2nd C Pu-1 1.005 0.176 0.078 testing for DG1101 on: C Pu-2 0.902 0.257 0.146 coat of DG1101 to CS Pu-1 0.983 0.009 0.001 same test coupons that
SS Pu-2 0.978 0.056 0.021
- Stainless steel (SS) P Pu-1 0.859 0.403 0.320
- Results show 2nd P Pu-2 0.903 0.405 0.310 C Am-1 0.980 0.169 0.063 decon efficacies as
- Plexiglas (P) good or better than 1st C Am-2 0.888 0.149 0.050 Contaminated with: CS Am-1 0.994 0.012 0.001 application.
CS Am-2 0.949 0.031 0.003
- Am-241 P Am-1 1.002 0.011 0.001 P Am-2 0.913 0.012 0.001
- Cs-137 C Cs-1 1.006 0.834 0.737 C Cs-2 0.974 0.822 0.745 CS Cs-1 0.998 0.010 0.002 CS Cs-2 1.002 0.014 0.002 SS Cs-1 0.998 0.039 0.008 SS Cs-2 0.986 0.019 0.003 P Cs-1 0.912 0.005 <MDA P Cs-2 0.953 0.004 <MDA Notes: MDA = Minimum detectable activity C Pu = concrete, plutonium; CS Am = carbon steel, americium; SS = stainless steel; P = Plexiglas; etc
Decontamination Testing of DG 1101 Radionuclide Solutions
- NIST traceable
- Prepared 1uCi/ml from stock solutions
- Am-241: AmCl3 in 1N HCl
- Pu-239: Pu(NO3)4 in 4M HNO3
- Cs-137: CsCl in 0.1M HCl Coupon Materials
- Construction grade concrete cores, uniformly sectioned
- Carbon steel 3 x 3 x 1/8
- 300-series Stainless steel 3 x 3 x 1/4
- PlexiGlas 3 x 3
Decontamination Testing of DG 1101 Coupon Contamination
- Placed on wire racks
- ~1 Ci each deposited using pipettor
- Carbon steel showed visible corrosion Coupon Coating Application and Removal
- Initial counts measured
- Coupons coated with DG1101, spread with spatula and excess allowed to drip off
- 24 hr. dry time
- All coupons easy to peel, most difficult was concrete
- Coatings all removed in single sheet with no fracture
- Carbon steel no longer had visible corrosion on surface
Decontamination Testing of DG 1101 Analytical Method and Data Workup
- Cs-137 counted for 1000 s w/Canberra Ge detector, peak area used to calculate activity
- Am-241 and Pu-239 counted for 120 s w/Ludlum 43-1 and Eberline E600
- Calibration coupons used for all cases
- % Decon = Initial Activity - Final Activity x 100 Initial Activity
Results 100%
90%
80%
70%
1st decon 60%
% Decon Pu 50% Am Cs 40%
2nd 30% decon 20%
10%
0%
Concrete Carbon steel Stainless steel PlexiGlas Material
Pu Glovebox Decon at LLNL Glovebox (~ 4 1/2 ft x 8 ft x 9 ft)
- Cast steel floor, Al walls, Lexan windows and Hypalon gloves
- Commissioned in 1964 to cold roll Pu metal
- In 1996 a spill of Pu-238 occurred
- Measurements at < 1 inch >>1,000,000 cpm (off-scale)
- Previous unsuccessful decontamination efforts involved a commercially available strippable film coating
Field Test DG 1101 Application
- Applied with trowel, allowed to dry overnight
- Lexan window deconned 2x, Steel floor and Al siding 3x
- DFs measured as ratio of original alpha activity at 1.5 inch stand-off to activity measured after each decon
- Initial contamination levels averaged
- 74,000 dpm for cast steel horizontal floor
- 56,000 dpm for aluminum siding
- 54,000 dpm for Lexan window
Results One application
- Activity on steel floor was reduced by 57% (SD=7%) and on the Lexan window by 37% (SD=8%)
Additional applications
- Lexan window after 2nd application overall 99.5% removal (SD=0.1%)
- Steel floor after 2nd and 3rd application overall 99.4% (SD=0.3%)
- After 2 and 3 applications of DG 1101, activity was reduced to <400 dpm in almost all cases
- Given the highly contaminated nature of the surfaces within the glove-box, this decontamination efficiency is considered excellent
Operational Perspectives
- The Nuclear Materials Processing and Technology Program personnel conducting the decon activities reported that the material had a good workability and allowed sufficient working time before drying.
- In general the material adhered to the sides of the glove-box without an excessive amount of dripping being observed.
- DG 1101 was able to penetrate crevices and was easily removed from all surfaces with the exception of the Hypalon gloves.
- While hand application was used for the study, personnel commented that spray application might be advantageous for future applications.
- [Comment from CBI: DG 1120 is now available for spray applications.]
Summary
- Lab Environ
- Decon Gel 1101 demonstrated effective on Pu-239, Am-241, and Cs- 137 radioisotopes
- 2nd decon factors as good or better than 1st application
- Cs on concrete most difficult case, R&D in progress
- Field Application
- Application of DG 1101 to Pu decon of highly contaminated glovebox at LLNL demonstrated excellent efficacy overall
- Full Reports Available
- Sandia and LLNL reports available upon request at CBI booth or contact M. ONeill, CTO, CBI
- moneill@cellularbioengineering.com