Less than seven feet stand between 41 workers trapped in Uttarakhand's Silkyari tunnel and freedom from their underground prison of 17 days, Lieutenant General Syed Ata Hasnain (retd.), a member of the National Disaster Management Authority, said Tuesday. Rescue teams are clearing the final few metres of debris - thanks to the banned manual "rat-hole"-mining technique employed after high-tech machines, or augers, failed to drill 60 metres - and lay two-feet wide pipes to create an escape route.