If you mirrored the drives - sure.
The instructions will vary depending on your OS (presumably Linux - but which version and distro) and your LVM. I can tell you how to do it for AIX, HP-UX or Solaris, but, frankly, I've never had any need to try it for Linux.
This link should help:
You're interested in Section 13.5 - remove an old disk.
BTW: you have a good backup, don't you? And you've previously tested your backup procedure, so you're confident the backup will restore correctly. Right?
Good luck .. PSM