Distinction between "process" and "covered process"

What is the distinction between a "process" and a "covered process" under the risk management program regulations at 40 CFR Part 68?

Process means any activity involving a regulated substance, including any use, storage, manufacturing, handling, or on-site movement of such substances, or combination of these activities.  A "covered process" is a process that contains a regulated substance in excess of a threshold quantity (40 CFR §68.3).