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Cementitious Wasteforms for Immobilization of Low-Activity Radioactive Wastes

Published online by Cambridge University Press:  15 February 2011

Dawn Wellman
Affiliation:
Pacific Northwest National Laboratory, Richland, WA, U.S.A.
Chase Bovaird
Affiliation:
Pacific Northwest National Laboratory, Richland, WA, U.S.A.
Kent Parker
Affiliation:
Pacific Northwest National Laboratory, Richland, WA, U.S.A.
Elsa Cordova
Affiliation:
Pacific Northwest National Laboratory, Richland, WA, U.S.A.
Aaron Davis
Affiliation:
Pacific Northwest National Laboratory, Richland, WA, U.S.A.
Shas Mattigod
Affiliation:
Pacific Northwest National Laboratory, Richland, WA, U.S.A.
Laura Powers
Affiliation:
Wiss, Janney, Elstner Associates, Inc., Northbrook, IL, U.S.A.
Marcus Wood
Affiliation:
CHPRC, Richland, WA, U.S.A.
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Abstract

Solidification of low-activity wastes with cementitious materials is a widely accepted technique that contains and isolates waste from the hydrologic environment. The radionuclides I-129, Se-75, Tc-99, and U-238 are identified as long-term dose contributors. The anionic nature of these radionuclides in aqueous solutions allows them to readily leach into the subsurface environment. Any failure of concrete encasement may result in water intrusion and consequent mobilization of radionuclides from the waste packages via mass flow and/or diffusion into the surrounding subsurface environment. Assessing the long-term performance of waste grouts for encasement of radionuclides requires understanding the: 1) speciation and interaction of the radionuclides within the concrete wasteform, 2) diffusion of radionuclide species when contacted with vadose zone porewater or groundwater under environmentally relevant conditions, and 3) long-term durability and weathering of concrete waste forms. An improved understanding of the interactions of long-lived radionuclides in cementitious matrices will improve predictions of the long-term fate of these sequestered contaminants. An integrated laboratory investigation has been conducted including a: 1) multifaceted spectroscopic investigation to interrogate the speciation and interaction of radionuclides within concrete wasteforms, 2) solubility tests to quantify the stability of solid phases identified as radionuclide-controlling phases, 3) quantify the diffusion of radionuclides from concrete wasteforms into surrounding subsurface sediment under realistic moisture contents (4%, 7%, and 15% by weight moisture content), 4) quantify the long-term durability of concrete waste forms as a function environmental parameters relevant to depository conditions, and 5) identify the formation of secondary phases or processes (microcracking) that influence radionuclide retention. Data obtained from this investigation provides valuable information for understanding the speciation, behavior, and fate of radionuclides immobilized within concrete wasteforms under vadose zone conditions and underscores the necessity for robust, multi-disciplinary performance assessments for concrete waste forms.

Type
Research Article
Copyright
Copyright © Materials Research Society 2009

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References

1 Al-Khayat, H, Haque, MN, and Fattuhi, NI. 2002. “Concrete Carbonation in Arid Climate.” Materials and Structures 35:421426.Google Scholar
2 ANSI. 1986. Measurement of the Leachability of Solidified Low-Level Radioactive Wastes Short-Term Test Procedure, American Nuclear Society, Chicago.Google Scholar
3 AC, Garrabrants, and Kosson, DS. 2003. “Modeling Moisture Transport from a Portland Cement-Based Material During Storage in Reactive and Inert Atmospheres.” Drying Technology 21(5):775805.Google Scholar
4 AC, Garrabrants, Sanchez, F, Gervais, C, Moszkowicz, P, and Kosson, DS. 2002. “The Effect of Storage in an Inert Atmosphere on the Release of Inorganic Constituents During Intermittent Wetting of a Cement-Based Material.” Journal of Hazardous Materials B91:159185.Google Scholar
5 AC, Garrabrants, Sanchez, F, and Kosson, DS. 2004. “Changes in Constituent Equilibrium Leaching and Pore Water Characteristics of a Portland Cement Mortar as a Result of Carbonation.” Waste Management 24:1936.Google Scholar
6 Gervais, C, Garrabrants, AC, Sanchez, F, Barna, R, Moszkowicz, P, and Kosson, DS. 2004. “The Effects of Carbonation and Drying During Intermittent Leaching on the Release of Inorganic Constituents from a Cement-Based Matrix.” Cement and Concrete Research 34:119131.Google Scholar
7 FM, Mann, Puigh, RJ II, Finfrock, SH, Freeman, J, J., E., Khaleel, R, Bacon, DH, Bergeron, MP, McGrail, PB, and Wurstner, SK. 2001. Hanford Immobilized Low-Activity Waste Performance Assessment: 2001 Version, DOE/ORP-2000-24, Rev. B, Pacific Northwest National Laboratory, Richland, WA.Google Scholar
8 BP, McGrail, Martin, PFC, and Lindenmeier, CW. 1997a. “Accelerated Testing of Waste Forms Using a Novel Pressurized Unsaturated Flow (Puf) Method.” In: Materials Research Society Symposium Proceedings.Google Scholar
9 BP, McGrail, Martin, PFC, and Lindenmeier, CW. 1999. “Method and Apparatus for Measuring Coupled Flow, Transport, and Reaction Processes under Liquid Unsaturated Flow Conditions.” In: Battelle Memorial Institute.Google Scholar
10 PB, McGrail, Ebert, WL, Bakel, AJ, and Peeler, DK. 1997b. “Measurement of Kinetic Rate Law Parameters on a Na-Ca-Al Borosilicate Glass for Low-Activity Waste.” Journal of Nuclear Materials 249:175189.Google Scholar
11 EM, Pierce, McGrail, BP, Valenta, MM, and Strachan, DM. 2006. “The Accelerated Weathering of a Radioactive Low-Activity Waste Glass under Hydraulically Unsaturated Conditions: Experimental Results from a Pressurized Unsaturated Flow (Puf) Test.” Nuclear Technology 155(2):149155.Google Scholar
12 Sanchez, F, Garrabrants, AC, and Kosson, DS. 2003. “Effects of Intermittent Wetting on Concentration Profiles and Release from a Cement-Based Waste Matrix.” Environmental Engineering Science 20(2):135153.Google Scholar
13 Sanchez, F, Gervais, C, Garrabrants, AC, Barna, R, and Kosson, DS. 2002. “Leaching of Inorganic Contaminants from Cement-Based Waste Materials as a Result of Carbonation During Intermittent Wetting.” Waste Management 22:249260.Google Scholar
14 RJ, Serne, Conca, JL, LeGore, VL, Cantrell, KJ, Lindenmeier, CW, Campbell, JA, Amonette, JE, and Wood, MI. 1993. Solid-Waste Leach Characterization and Contaminant-Sediment Interactions, PNL-8889, Vol. 1, Pacific Northwest Laboratory, Richland, WA.Google Scholar
15 RJ, Serne, Lokken, RO, and Criscenti, LJ. 1992. “Characterization of Grouted Llw to Support Performance Assessment.” Waste Management 12:271287.Google Scholar
16 RJ, Serne, Martin, WJ, and LeGore, VL. 1995. Leach Test of Cladding Removal Waste Grout Using Hanford Groundwater, PNL-10745, Pacific Northwest Laboratory, Richland, Washington.Google Scholar
17 RJ, Serne, Martin, WJ, LeGore, VL, Lindenmeier, CW, McLaurine, SB, Martin, PFC, and Lokken, RO. 1989. Leach Tests on Grouts Made with Actual and Trace Metal-Spiked Synthetic Phosphate/Sulfate Waste., PNL-7121, Pacific Northwest Laboratory, Richland, Washington.Google Scholar
18 Toxicity Characteristic Leaching Procedure. 1992. Method 1311, Federal Registry,Google Scholar
19 DM, Wellman, Bovaird, CC, Parker, KE, Mattigod, SV, Wood, MI, Powers, L, and Clayton, LN. 2009. “Cementitious Wasteforms for Immobilization of Low-Activity Radioactive Wastes.” In: Concrete Materials: Properties, Performance and Applications. Columbus, F, Ed., Nova Science Publishers, Inc., Hauppauge, NY. Google Scholar
20 DM, Wellman, Mattigod, SV, Arey, BW, Wood, MI, and Forrester, SW. 2007. “Experimental Limitations Regarding the Formation and Characterization of Uranium-Mineral Phases in Concrete Waste Forms.” Cement and Concrete Research.Google Scholar
21 DM, Wellman, Mattigod, SV, Whyatt, GA, Powers, L, Parker, KE, Clayton, LN, and Wood, MI. 2008. “Effect of Iron and Carbonation on the Diffusion of Iodine and Rhenium in Waste Encasement Concrete and Soil Fill Material under Hydraulically Unsaturated Conditions.” Applied Geochemistry 23:22562271.Google Scholar
22 PJ, Wierenga, and Genuchten, MT Van. 1989. “Solute Transport through Small and Large Unsaturated Soil Columns.” Ground water 27(1):3542.Google Scholar
23 MI, Wood, Khaleel, R, Rittman, PD, Lu, AH, Finfrock, S, Serne, RJ, and Cantrell, KJ. 1995. Performance Assessment for the Disposal of Low-Level Waste in the 218-W-5 Burial Ground, WHC-EP-0645, Westinghouse Hanford Company, Richland, WA.Google Scholar