The sword of Damocles hangs over owners and workers of 40,000 brick-kilns as the Union Ministry of Environment and Forestry has proposed a ban on the excavation af top soil within a radius of 50 km from the coal -based thermal plants in the country.In fact, the draft of the notification, which the central government proposed to issue in this connection, has been sent to all state governments and others concerned, inviting objections, if any, from the parties and person to be affected.