A fuzzy approach for modelling radionuclide in lake system

Area of Science:

• Environmental Science
• Nuclear Engineering
• Water Resource Management

Background:

• Pressurised Heavy Water Reactors (PHWRs) generate radioactive liquid waste during operation and maintenance.
• Standard practice involves diluting low-level liquid waste and discharging it into water bodies.
• Controlled release of treated effluents from nuclear installations is essential.

Purpose of the Study:

• To predict the concentration of tritium ((3)H) released from the Kakrapar Atomic Power Station at Ratania Regulator.
• To assess potential human exposure to tritium in a natural ecosystem approximately 2.5 km from the discharge point.

Main Methods:

• A heuristic approach using a Fuzzy Rule Based (FRB) model was adopted due to data scarcity and complex lake geometry.
• Three hundred data points, generated via multiple regression analysis, were used to develop fuzzy rules with water flow and discharge concentration as inputs.
• One hundred additional data points were generated for model validation.

Main Results:

• The FRB model successfully predicted tritium ((3)H) concentration at Ratania Regulator.
• The model achieved a Root Mean Square Error (RMSE) of 1.95, indicating good agreement between predicted and actual values.
• The developed model demonstrates effective prediction capabilities for tritium in a natural ecosystem.

Conclusions:

• Fuzzy rule-based modeling provides a viable approach for predicting radionuclide concentrations in complex environmental systems.
• The model's accuracy supports its use in environmental monitoring and risk assessment for nuclear facilities.
• Effective management of radioactive liquid waste requires accurate prediction of environmental contaminant transport.