hdd failure

One of the disks that made my LVM go bye-bye in the first place seems to be dying aswell. Is there any way to make sure there's no data on it before I remove it from the lv/vg? I've restored the lv, but I'm reluctant to use it since one of the hdd's is spitting out a lot of errors.

If I remember correctly it's one of the drives that I last put in, so I don't think there's any data on it at all, but I'm not entirely sure.

And if I do an lvreduce/vgreduce, how am I sure that it removes the hdd I want to get out?

Sorry if I'm asking very obious questions here, but I'm not quite in to the LVM logic yet :)

-- marius