Thanks for the responses.
Richard: it takes that long because of the "-c -c" option. As Berend says, it runs badblocks which "beats up a block at a time" writing/reading patterns... looking for errors. The man page for mke2fs is helpful.
Sorry, I see it now in the subject line, I just didn't see it in the body of the original mail...
Would using smartctl to let the drive check itself help?
# smartctl --test=long /dev/sdc
Or you can initiate it and monitor the progress from the disk utility.
Last option... If the case isn't too difficult to open temporarily install it to a desktop computer to speed things up.
Thanks,
Richard