removing /var/empty on a non-system disk

[Gary Aitken]

something I'm not seeing

I've got a disk previously used as a sys disk I'm trying to clean up.
What's the key to removing /var/empty?

280 /hd1/var#sysctl kern.securelevel
kern.securelevel: -1
281 /hd1/var#ls -l
total 4
dr-xr-xr-x  2 root  wheel  512 Jan  3 00:55 empty
282 /hd1/var#chflags noschg empty
283 /hd1/var#chmod 777 empty
chmod: empty: Operation not permitted
284 /hd1/var#rmdir empty
rmdir: empty: Operation not permitted