Failure associated with abandoned room and pillar mineworkings can be seen to occur in three principal areas; the roof or floor of the working and in the pillars. The failure mechanisms associated with these three areas can have serious repercussions for the surface environment in terms of instability. With the ongoing abandonment of deep level coal mines throughout Europe, there is a significant interest in the effects of the water-table rebound due to cessation of water pumping upon the stability aspects, and hence the failure mechanisms common within overlying, shallow mineworkings. This paper attempts to identify the main effects of groundwater ingress on these shallow workings as the water-table recharges to its pre-mining levels, by initially examining the mechanisms of rebound and the factors which determine the rate of rebound. The main failure mechanisms which occur in room and pillar mines are identified and the effects of water upon them discussed. It is concluded that water inundation due to groundwater recharge could not only contribute to mine instability but it could also exacerbate currently unstable areas. Therefore, a thorough understanding of the effects outlined coupled with a quantitative analysis of the mechanisms of rebound and failure is necessary before comprehensive conceptual models of the effects of groundwater recharge upon shallow, abandoned mineworkings can be proposed.
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