Failing OS Backup Drive - How to remove properly?

[MattG 1]

I have DrivePool handling the storage disks, so in a hot-swap bay I have a drive that is used to hold the OS backups.  That drive is failing.  Had one bad cluster a few days ago, and now has several.  I formatted it hoping that the bad clusters would be identified and not used but after the format and one OS backup there are more bad clusters.  So I pulled it and stuck another drive in there.

 

Questions

1. At the moment, when I right click on the server in the Dashboard, the server thinks there are backups going back a few months (as it should).  How do I tell the server those backups don't exist anymore?
2. What is the "proper" way to remove a failed OS backup drive from the server?  How do I tell the server "hey, this drive is failing/has failed and it's being removed and will never return"?

 

Thank you for your help!

 

-Matt