NextGen air traffic control systems are in development to manage the increase in sector capacity needed to handle the anticapted increae in air traffic over the next twenty years. Automated separation assurance is the most developed theory for managing traffic which exceeds the human controller’s ability, but lacks the ability to pre-emptively identify potential problems. The intensity control measure is a human-managed task to be performed while automation handles routine separation that measures the amount of time until a pair of aircrafts face a near-mid-air-collsion in the face of an unplanned maneuever. This measure identifies serious potential problems before they happen, and allows the human controller to apply control to reduce this risk. This work identifies how oftehn high intensity pairs occur in current, 1.5x, 2x, and 3x traffic levels, and how often controllers are able to safely apply control. As traffic levels increase, the number of high intensity pairs increases, and the ability of controllers to safely manage such a large number of highly intense pairs varies.