Optimizing Emergency Logistics for the Offsite Hazardous Waste Management

Hazardous wastes pose increasing threats to people and environment during the processes of offsite collection, storage, treatment, and disposal. A novel game theoretic model, including two levels, is developed for the corresponding optimization of emergency logistics, where the upper level indicates the location and capacity problem for the regulator, and the lower level reflects the allocation problem for the emergency commander. Different from other works in the literature, we focus on the issue of multi-quality coverages (full and partial coverages) in the optimization of facility location and allocation. To be specific, the regulator decides the location plan and the corresponding capacity of storing emergency groups for multiple types of hazmats, so to minimizes the total potential environmental risk posed by incident sites; while the commander minimizes the total costs to provide an efficient allocation policy. To solve the bi-level programming model, two solution techniques, namely a KKT condition approach and a heuristic model, are designed and compared. The proposed model and solution techniques are then applied to a hypothetical case and a real-world case to demonstrate the practicality and provide managerial insights.