Waste Water Disposal: Polluted Aquifer Cleanup Optimization by Using Genetic Algorithms

Water produced constitutes a large amount of waste fluids during the production operation of an oil field. Underground injection for disposing of the waste water from hydrocarbon production is an engineering problem due to the possibility of leakage of injected pollutant material from the receiving medium to a drinking-water source. In this study, for the remediation of a polluted aquifer, a computer program was developed by using an analytical model approach based on hydrodynamic isolation, and the program was incorporated with genetic algorithms (GAs) for optimum design solution. As a case study, a contaminated area was created by using a ground water transport simulator based on the method of characteristics (MOC). Then the computer program was run to find the optimum solution for remediation, and the solution produced by the program was verified by using a ground water simulator. The plume was captured and the concentration level of chloride ion within the aquifer was diminished by using extraction wells. The analytical model approach provided different alternatives for appropriate isolation of plume. GAs were used as an optimization technique for making a decision among the alternatives, by consid ering operation time, number of wells, pumping rate, and draw down as decision variables and constraints.