The recycling centre at Totnes was closed for 90 minutes yesterday morning while bomb disposal experts removed a rocket propelled mortar which had been placed in a skip and narrowly missed being crushed by a digger.
Devon County Council, which owns the site, confirmed that the site was evacuated while police, then bomb squad officers, were called.
Investigators removed the mortar in a bomb-proof container for further examination. It is not yet known whether the mortar had already been deactivated before being disposed of in the skip, or whether it had potential to explode.
Roger Croad, Devon County Council's cabinet member responsible for recycling centres, said the rocket should never have been placed in the skip in the first place.
"We like to think that we can recycle most things to avoid them going into landfill, but rocket propelled mortars are definitely not on our list of recyclables," he said.
"Seriously though, it's rather irresponsible to leave ammunition or explosives at your local recycling centre, and possibly endangering staff and the public."