Assessment of Abandoned Coal Mines as Urban Reservoirs.

The closure of many coal mines has resulted in many being used as massive underground mine water storage systems in urban areas. We used a comprehensive fuzzy method to assess the suitability of abandoned coal mines as underground reservoirs. Five first-level and four second-level indices were chosen based on the hydrogeological conditions. The degree of membership of each index was determined and quantitatively graded into suitability grades of I–V using a trapezoidal fuzzy number membership function. The weight of each index was determined in accordance with information entropy. Abandoned mines in Xuzhou city were examined as a case study. The degree of suitability of the water in 14 abandoned mines was assessed. Six of the abandoned mines earned a suitability grade of I and II and should be given priority. The evaluation of abandoned mines as underground reservoirs provides a new means to potentially secure an emergency water supply in urban settings. [ABSTRACT FROM AUTHOR]