Risk classification of abandoned oil wells in coal mine field and selection of plugging scheme

There are a lot of abandoned oil wells in Shuangma Mine in Majiatan mining area of Lingwu City of Ningxia, these abandoned oil wells result in serious threat for safe mining in coal mines. Because these abandoned wells were mostly exploration wells drilled mostly during 1950s and 1960s, their data have been lost seriously. Based on the influence of six different indexes such as hazardous gas content on the safe mining in coal mines, the paper classified these abandoned oil wells, and then adopted different solutions according to different types of abandoned oil wells so as to achieve the purpose of safe and highly efficient mining in coal mines.