E Environmental management has now become a very important issue in industrial activities. Many government regulations have been made to ensure that all environmental conditions associated with industrial activities remain safe and under control. This study aims to design a model for optimizing the performance of a cooling waste treatment plant with a System dynamics approach. The performance indicators of refrigeration waste treatment are the minimization of the volume of B3 waste and the efficiency of the use of new chillers. The research stages are carried out by conducting a system analysis study, designing a Causal Loop Diagram, and designing a performance optimization model based on a system dynamics approach. Model verification is done by comparing whether the model variables can reflect the variables that exist in real process conditions. Model validation is done by comparing the model results with actual performance. Several alternative processing strategies and policies are expected to anticipate future production fluctuations while maintaining the quality and performance standards of the waste treatment plant. The result of the model design that has been made is the Waste Cooling Performance Optimization Model with the input value of the Coolant missing Hocut Concentration — Percentage of Achievement of Refrigeration waste treatment, Process: 25 Auxiliary Formula. Output : waste in WWT — Bare Hocut Cost. Using Powersim Studio 10 Express Software. The optimization model design has been validated using the MAPE method with a MAPE value of 1.53% (pessimistic waste treatment conditions), a MAPE value of 3.02% (optimistic waste treatment conditions) and a MAPE value of 0.83% (moderate waste treatment conditions). The standard OK MAPE value < 5%, this indicates that the model is very representative of field conditions. The model simulation for alternative strategies obtains a significant potential for cost savings using Hocut obtained from the difference in usage for 10 years (2016 - 2025) which is 30 M (pessimistic waste treatment) - 4.4 M (optimistic waste treatment) = 25.6 M ( 85% cost-effective). In addition, the simulation results also get the potential for minimizing B3 waste for 10 years (2016 — 2025) which is 7.2 million liters (pessimistic waste treatment) — 0.97 million (optimistic waste treatment) ---- 6.2 million liters (86 % waste decreaEnvironmental management has now become a very important issue in industrial activities. Many government regulations have been made to ensure that all environmental conditions associated with industrial activities remain safe and under control. This study aims to design a model for optimizing the performance of a cooling waste treatment plant with a System dynamics approach. The performance indicators of refrigeration waste treatment are the minimization of the volume of B3 waste and the efficiency of the use of new chillers. The research stages are carried out by conducting a system analysis study, designing a Causal Loop Diagram, and designing a performance optimization model based on a system dynamics approach. Model verification is done by comparing whether the model variables can reflect the variables that exist in real process conditions. Model validation is done by comparing the model results with actual performance. Several alternative processing strategies and policies are expected to anticipate future production fluctuations while maintaining the quality and performance standards of the waste treatment plant. The result of the model design that has been made is the Waste Cooling Performance Optimization Model with the input value of the Coolant missing Hocut Concentration — Percentage of Achievement of Refrigeration waste treatment, Process: 25 Auxiliary Formula. Output : waste in WWT — Bare Hocut Cost. Using Powersim Studio 10 Express Software. The optimization model design has been validated using the MAPE method with a MAPE value of 1.53% (pessimistic waste treatment conditions), a MAPE value of 3.02% (optimistic waste treatment conditions) and a MAPE value of 0.83% (moderate waste treatment conditions). The standard OK MAPE value < 5%, this indicates that the model is very representative of field conditions. The model simulation for alternative strategies obtains a significant potential for cost savings using Hocut obtained from the difference in usage for 10 years (2016 - 2025) which is 30 M (pessimistic waste treatment) - 4.4 M (optimistic waste treatment) = 25.6 M ( 85% cost-effective). In addition, the simulation results also get the potential for minimizing B3 waste for 10 years (2016 — 2025) which is 7.2 million liters (pessimistic waste treatment) — 0.97 million (optimistic waste treatment) ---- 6.2 million liters (86 % waste decreased)sed) Keywords: Environmental management, Waste Cooling, Waste installation, Optimization model, System dynamics, Performance Indicators.