scholarly journals Relevance of biotic pathways to the long-term regulation of nuclear waste disposal. Estimation of radiation dose to man resulting from biotic transport: the BIOPORT/MAXI1 software package. Volume 5

1985 ◽  
Author(s):  
D.H. McKenzie ◽  
L.L. Cadwell ◽  
K.A. Gano ◽  
W.E. Jr. Kennedy ◽  
B.A. Napier ◽  
...  
Keyword(s):  
Radiation Dose ◽  
Nuclear Waste ◽  
Waste Disposal ◽  
Software Package ◽  
Nuclear Waste Disposal

Monitoring deep subsurface microbiota for assessment of safe long-term nuclear waste disposal

1996 ◽  
Vol 42 (4) ◽  
pp. 375-381 ◽  
Author(s):  
David C. White ◽  
David B. Ringelberg
Keyword(s):  
Nuclear Waste ◽  
Waste Disposal ◽  
Nuclear Waste Disposal ◽  
Physiological Status ◽  
Deep Subsurface ◽  
Long Term Storage ◽  
Lipid Biomarker ◽  
Potential Problems

Microbes with their resistance to heat and radioactivity, if present and metabolically active, could have major effects on the safety of nuclear waste disposal by posing potential problems in long-term containment. This paper reviews the applicability of the signature lipid biomarker (SLB) analysis in the quantitative assessment of the viable biomass, community composition, and nutritional/physiological status of the subsurface microbiota as it exists in situ in subsurface samples. The samples described in this review are not unlike those expected to be recovered from proposed deep subsurface disposal sites. Assessment of the microbial community ecology using SLB analysis can be utilized to predict potential problems engendered by microbial metabolic activities of these communities in breaching containment by microbially facilitated corrosion and in the potential for subsequent facilitated transport of nuclides into the environment. SLB analysis of the in situ microbial ecology can be utilized to monitor the feasibility of containment options in modeling tests at the specific disposal sites.Key words: nuclear waste, deep subsurface, microbiota, microbial corrosion, safe long-term storage, signature lipid biomarkers.

Nuclear Waste Disposal: The Interface Between Performance Assessment and Research

1981 ◽  
Vol 6 ◽  
Author(s):  
R.B. Lyon
Keyword(s):  
Radiation Dose ◽  
Nuclear Waste ◽  
Waste Disposal ◽  
Systems Analysis ◽  
Nuclear Waste Disposal ◽  
Laboratory Research ◽  
Natural Systems ◽  
Wide Variability ◽  
Irreducible Uncertainty ◽  
Nuclear Fuel Waste

ABSTRACTThe potential impact of the post-closure phase of a nuclear fuel waste disposal project is radiation dose to man. Radiation dose is estimated as the end product of a total systems analysis. Field and laboratory research must be assimilated in a form that can be accepted by the total systems analysis procedure. A central focus of this assimilation must be the consideration of uncertainties in the analysis and data used. Irreducible uncertainty arises because of the wide variability in natural systems and the unprecedented extrapolation into the distant future. The SYVAC computer program provides a framework for assimilation of the results of the field and laboratory research with a systematic treatment of uncertainty. A SYVAC assessment of the post-closure performance of a Canadian nuclear waste disposal facility is presented with particular illustrations of the interface between the assessment models and data and the field and laboratory research.

scholarly journals Relevance of biotic pathways to the long-term regulation of nuclear waste disposal: Phase 2, Final report

1986 ◽  
Author(s):  
D.H. McKenzie ◽  
L.L. Cadwell ◽  
W.E. Jr. Kennedy ◽  
L.A. Prohammer ◽  
M.A. Simmons
Keyword(s):  
Nuclear Waste ◽  
Waste Disposal ◽  
Nuclear Waste Disposal ◽  
Final Report ◽  
Phase 2

scholarly journals Geochemical benchmark tests to validate the conversion of thermodynamic data for TOUGHREACT

2021 ◽  
Vol 1 ◽  
pp. 161-162
Author(s):  
Torben Weyand ◽  
Holger Seher ◽  
Guido Bracke
Keyword(s):  
Nuclear Waste ◽  
Waste Disposal ◽  
Thermodynamic Data ◽  
Selection Process ◽  
Nuclear Waste Disposal ◽  
Crystalline Rock ◽  
Benchmark Tests ◽  
High Level ◽  
Saline Solutions

Abstract. According to the ongoing site selection process for a repository for high-level radioactive waste in Germany, rock salt, clay and crystalline rock are possible host rocks. The pore water of these rocks contains saline solutions with high ionic strengths. To model the speciation and/or migration of radionuclides in long-term safety analyses for nuclear waste disposal, a geochemical code that includes thermodynamic data suitable for saline solutions is needed. Thermodynamic equilibrium in saline solutions with high ionic strengths is usually modelled using the Pitzer approach (Pitzer, 1991). Within the context of nuclear waste disposal, the THEREDA project (Moog et al., 2015) provides thermodynamic data for some widely used geochemical codes (PHREEQC, Geochemist's Workbench, ChemApp, and EQ 3/6) using the Pitzer approach; however, for modelling in long-term safety analyses for nuclear waste disposal, another geochemical code, TOUGHREACT, is used. Therefore, scripts were developed to convert thermodynamic data of the THEREDA project to be applicable in TOUGHREACT. The scripts were validated by benchmark tests and by comparing calculations using PHREEQC and TOUGHREACT (Weyand et al., 2021). In total, 50 different benchmark tests were performed considering 3 specific geochemical systems, which are relevant to long-term safety analyses: (1) oceanic salt system, polythermal: K, Mg, Ca, Cl, SO4, H2O(l), (2) actinide system, isothermal: Am(III), Cm(III), Nd(III), Na, Mg, Ca, Cl, OH, H2O(l) and (3) carbonate system, isothermal: Na, K, Mg, Ca, Cl, SO4, HCO3/CO2(g), H2O(l). Each benchmark test considered specific ion concentrations in solution and in gaseous phases in the presence of specific minerals. The benchmark tests derived the geochemical equilibria and the results of both codes were compared to each other and to experimental data. The results of the calculations using both codes showed a good correlation. Remaining deviations can be explained by technical differences of the codes.

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