Response of Heavy Metals to Microseism in Coal Mining Subsidence Water of Huainan, China

Abstract

Coal mining causes surface subsidence, and the accumulated water body is constantly affected by the mining microseism in this process. Understanding the relationship between the subsided water quality and microseism plays a special role in assessing the environmental impact of mining activities. Based on sampling and monitoring, analyzing, and evaluating the Pansan subsided water area of Huainan, the influence of microseism activity on heavy metal elements in subsided water was verified. We found that the microseism effects decreased the contents of Zn, Pb, and Cu in the subsided water by 43.76%, 35.88%, and 28.83%, respectively, and Cd was not detected. The mechanism of heavy metal evolution in the water–sediment system under microseism factors was further explored by simulating experiments with similar materials. The results showed that the mining microseism increases the heavy metal adsorption capacity of suspended solids, and the dissolved heavy metals in water were transformed into suspended heavy metals. The heavy metals of subsided water eventually accumulate in the sediment, and the purpose of controlling heavy metal pollution can be achieved through regular cleaning of the bottom sediment.