disk non-destructive bad-block write/fix?

I have a system I need to back up and my only available backup disk is
throwing a lot of errors like:

   (da0:umass-sim0:0:0:0): WRITE(10). CDB: 2a 00 3c fd e5 68 00 00 40 00
   (da0:umass-sim0:0:0:0): CAM status: CCB request completed with an error
   (da0:umass-sim0:0:0:0): Retrying command
   (da0:umass-sim0:0:0:0): WRITE(10). CDB: 2a 00 3c fd e6 68 00 00 20 00
   (da0:umass-sim0:0:0:0): CAM status: CCB request completed with an error

Is there a way to exercise the free blocks on a ufs disk and move all
defective ones to the bad-block list?

Or is that already happening in the above scenario?

The command was
   find . | grep -iv -f ./backup_ignores.txt | cpio -pmd /mnt/backup_20220919/

The disk is about 40% full but I'm wondering if the whole rest of it is
trashed.

Thanks,

Gary