All of the disciplines you are asking about are seperated at our power plant. I am in Operations. Ours goes like this. Ops Director, 3 Unit Department Leaders, Site Shift Manager, Shift Manager, Control Room Supervisor, Senior Reactor Operator, Reactor Operator, and Non-Licensed Operator. The other departments have a similar chain. They all report to the site Nuclear Plant Manager. We have an VP of Engineering, looking for VP Operations, and the report to Sr. VP Nuclear. He reports to President downtown. Key thing is they all have input into the plants day to day ops. The guys in the control have the ultimate responsibility because they are the ones with their name on the License. Hope this helps.