This paper describes mathematical models of off-nominal events and the corresponding mitigation strategies in Super Density Operations. Research in mitigation strategies focuses on procedural and algorithmic solutions to mitigating the off-nominal condition and returning the system back to the nominal state when it is feasible to do so. Mitigation strategies investigated in this paper include use of flexible airspace to perform path stretching and reroutes, placement of holding patterns, as well as speed control to open gaps in streams of aircraft. We also describe a computation framework developed to conduct analysis of off-nominal conditions and report results of initial simulation studies demonstrating the feasibility of the developed approach.