A team is set to work its way through Kingley Vale Nature Reserve to check for ordinances left from the Second World War.
The army and bomb disposal teams have been called to the reserve before as in the case of a ten-year-old boy who found a mortar shell in the woods last year.
Now DEFRA has asked for more clearance work at the former military training area near West Stoke and Funtington.
Steve Marner of Fellows International Ltd said he and two other people would be walking through the forest checking for bombs and other devices but would call the army and police if they found anything.
He said: “We’re going to search up and down in the woods and in the area for unexploded ordinances.
“It’s a very interesting place to be honest, it was used as a military training area for quite a long time.
“There’s been some clearance done but things are still turning up, so DEFRA have contracted us to do some clearance and that’s going to start in the next few weeks.”
He said the work would take about five weeks to complete and the team would be clearly dressed in high-visibility jackets.
Anyone who sees what could be an old munitions device in the area is asked to not touch it, to mark its location and report it to the reserve manager and police.