Embodiments of archival storage system are disclosed. The archival storage system includes one or more removable disk drives that provide random access and are readily expandable. In embodiments, some or all of the data within the removable disk drive(s) is immutable. The archiving system creates a designation for the data representing the data as having Write Once Read Many (WORM) protection. Actions associated with the data may be received and determined to be read accesses. If the actions are something other than a read access, the archiving system, in embodiments, prevents the action on the data.