[CentOS] LVM, usb drives, Active Directory

I have a client with a handful of USB drives connected to a CentOS
box.   I am charged with binding the USB drives together into a single
LVM for a cheap storage data pool (10 x 1 TB usb drives = 10 TB cheap
storage in a single mount point).

The next fun piece is how to incorporate that storage space into an
existing Active Directory structure to apply AD acls for limited
access.

I'd rather not use Samba, as that is its own infrastructure and
maintains its own credentials database.

What are my best options?

Thanks.

Scott