New Delhi, Oct. 9 -- Sometime in the afternoon on September 29, the Lilagar river, usually a calm tributary of the Mahanadi but at the time in spate for days following heavy rains, changed course and broke through an embankment to flood a Coal India mine in Chhattisgarh's Dipka. It inundated open pits, submerging heavy machinery, and knocking out operations that may take weeks to normalise.

Started in 1976 and run by Coal India subsidiary South Eastern Coalfields Limited (SECL), the Dipka mine contributes around 5% of Coal India's output. Questions are now being raised about how the mine was allowed to expand close to a river, and has renewed concerns over several similar projects in the state, the chief among which are Kusmunda, Parsa, an...