OPTIMAL-CONTROL OF GROUNDWATER QUALITY MANAGEMENT - NONLINEAR-PROGRAMMING APPROACH

A management model is developed that uses a nonlinear programming approach to solve the optimal control problem of managing the generation and disposal of agricultural and dairy waste. The permissible controls are subject to physical, economic, and social constraints. The model uses a state response matrix to represent the response of the physical state of the system, and a policy response matrix that reflects the effect of policy actions such as pumping, recharge, and manure disposal on the state of the system. Unlike some combined simulation/optimization approaches, this model includes the dynamic response of the system as an explicit part of the optimization. To evaluate the applicability of the model to actual policy problems, the model is implemented in the Chino ground-water basin, California. Based on the alternative scenarios analyzed, a manure-treatment and -disposal program coupled with an artificial-recharge program are proposed. The rate and schedule of treatment, disposal, and recharge are determined on the basis of the transport capacity of the underlying aquifer and associated costs. The model may be used for analysis of ground-water quality regulations or other management options on the physical state and economic parameters of the system.