Mathematical simulation of sediment and radionuclide transport in coastal waters. Volume 1. Testing of the sediment/radionuclide transport model, FETRA

A well-designed environmental monitoring plan is essential for safety of uranium mining and processing operations. Evaluating the possible uncertainties in a numerical model helps in enhancing the model output and also increases the reliability over the model results. For a radionuclide transport model, distribution co-efficient is a sensitive parameter and major source of uncertainty in results. In this study, an approach to quantify input source of uncertainty of distribution co-efficient in an engineered tailings pond in Northern Karnataka, India has been carried out. Probabilistic analysis such as Response Surface Method and Monte Carlo Simulation are used to propagate uncertainty. This study considers uncertainty associated with intrinsic heterogeneity of natural systems and estimates the probability that dose rate value through drinking water pathway around the tailings pond exceeds the WHO guidelines for drinking water. The radionuclides considered in this study are 238U, 234U, 230Th and 226Ra. This study can be used to study the impact of distribution co-efficient on the radionuclide transport model.Key words: Numerical modelling, Tailings pond area, Uranium mining, Uncertainty, &#160;Distribution coefficient&#160;

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Radionuclide transport model for risk evaluation of high-level radioactive waste in Northwestern China

Human and Ecological Risk Assessment An International Journal ◽

10.1080/10807039.2017.1361811 ◽

2017 ◽

Vol 23 (8) ◽

pp. 2017-2032 ◽

Cited By ~ 3

Author(s):

Xiaoyuan Cao ◽

Litang Hu ◽

Jinsheng Wang ◽

Jingrui Wang

Keyword(s):

Radioactive Waste ◽

Risk Evaluation ◽

Transport Model ◽

Northwestern China ◽

Radionuclide Transport ◽

High Level Radioactive Waste ◽

High Level

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Data Reduction for Radionuclide Transport Codes Used in Performance Assessments: An Example of Simplification Process

MRS Proceedings ◽

10.1557/proc-506-797 ◽

1997 ◽

Vol 506 ◽

Cited By ~ 1

Author(s):

B. Dverstorp ◽

B. Mendes ◽

A. Pereira ◽

B. Sundström

Keyword(s):

Data Reduction ◽

Transport Model ◽

Computer Experiments ◽

Simple Calculation ◽

Radionuclide Transport ◽

Transport Pathway ◽

Transport Models ◽

Transport Pathways ◽

Flow Parameters ◽

Spatially Varying

ABSTRACTThe input data required for transport models for use in long-term risk assessments of repositories for radioactive waste, in geological media, are intrinsic to the performance of the models. The flow parameters utilized in these models typically come from 2 or 3D hydro-geological calculations done in a prior phase of an assessment. This paper examines some of the standard simplifications introduced when hydrogeological data are reduced to ID as is often required for radionuclide transport models. Two key aspects of data reduction are the determination of average properties of fractured media between and along transport pathways. To quantify possible errors associated with these reduction procedures, two computer experiments have been done. We show that the use of effective flow parameters, representing the average properties of a set of independent transport pathways, in a 1 D radionuclide transport model can result in an underestimation of peak releases by one order of magnitude or more. This result is valid for short-lived nuclides whenever retardation is an important factor. On the other hand, averaging of spatially varying transport properties along a transport pathway may lead to unjustified conservatism. A simple calculation example using Monte Carlo technique, shows that a model that does not take into account spatially varying retardation properties along the transport pathways may overestimate peak release rates by several orders of magnitude. We conclude that more sophisticated transport models taking into account available hydrogeological information on spatial variability are needed to fully understand the potential errors associated with consequence calculations in the performance assessment

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Simulation of the fate of faecal bacteria in estuarine and coastal waters based on a fractionated sediment transport model

China Ocean Engineering ◽

10.1007/s13344-017-0045-y ◽

2017 ◽

Vol 31 (4) ◽

pp. 389-395

Author(s):

Chen Yang ◽

Ying Liu

Keyword(s):

Sediment Transport ◽

Coastal Waters ◽

Transport Model ◽

Sediment Transport Model ◽

Faecal Bacteria

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