clipped

Im having raidable bases not despawn properly, my map has filled up with these empty bases. The zone has disappeared and theres nothing in tc so I wouldve thought that these would just decay properly, any ideas? I have a feeling that its because I reboot my server regularly and the server hasnt had time to destroy the assets or something. Help would be appreciated if this is something thats happened before. I have been going through the forums and couldnt find any solutions.