In general...
data tapes will be associated with the device class within an atl
in other words you may checkout all libvols, delete all drives, & delete the
library and all is still well !
Then if you define a new library, define your drives back to that new
library, (update your deviceclass for the drives to reference the new
library) then do "checkin libvol" commands with status=private against all
allocated tape volumes you'll be good to go ;-)  You will still be left at
getting a list of all unused tapes and checking them in as status=scratch
though.
AND all the used tapes will (should) go back to scratch status when they are
emptied (even though you just checked them in as private but had to 'cause
they had data on them)

Dwight

in moving tsm environments around with 3494's I ended up changing the name
of my libraries and the scratch & private codes used within libraries and
basically did what I've mentioned above... every thing worked fine (but that
was all IBM equipment... S70 servers and 3494 ATLs)