Shutting down my Elastic Image doesn't delete my ebs volume

After working with elastic bamboo for a while on BEAC, I make changes to the volume, generate my new snapshot then shutdown all my agents and start them up with a new volume. If i do that enough, the volume list in the AWS console will get full and I wont be able to create any more volumes, stopping me from starting any working agents.

Bamboo should delete the volume when it shuts down an agent, it doesn't seam to be doing that.