The application of environmental Gini coefficient (EGC) in allocating wastewater discharge permit: The case study of watershed total mass control in Tianjin, China

The allocation of wastewater discharge permit is always a challenge in total mass control due to the conflicts between environmental equality and efficiency. In this article, we introduce a framework to allocate discharge permit by using Gini coefficient, a widely used index of income inequality in economics. The environmental Gini coefficient (EGC) method is based on a multi-criteria system, including land area, population, gross domestic product (GDP), and environmental capacity. The allocation of chemical oxygen demand (COD) in the watershed at Tianjin, China is chosen as a case study to illustrate the application of this framework. The results show that the EGC method can provide a profound insight for environmental management with a focus on balance of environmental equality and efficiency for the policy-makers, especially in developing countries.