Multiple entries of a disk volume appearing

I have been trying to figure this out for several days now, and I'm lost. I have a secondary storage disk installed in my old Powermac G4. It mounts fine, and I can read everything on it. But when I transfer files to it, they seem to disappear.

Going into Disk Utility, everything seems fine, too. But when I bring up Terminal and go into /Volumes, there's something seriously wrong. The directory shows 'Mac HD' and 'Storage', the two volumes that should be there, but there are also 'Storage 1' and 'Storage 2' in there. The files I transferred to 'Storage' are showing up on that volume, but not on the duplicate volumes, and it appears that it is actually 'Storage 2' that is mounting. 😕

So WTF is going on here? How did this happen, and how do I fix it? Since the files I need are on the original instance of the volume, it looks like I need to remove the two duplicates and re-link the mount point to the original disk. But how?

Thinking about it a little more, it occurred to me that the cause of this is the random freezing my computer has been doing lately... It gets improperly shut down pretty frequently as a result, which is screwing up the file system entries. So that part of the mystery is solved.

But that still leaves... how to fix it?