Slushflow consists of a mixture of snow, water, and ice and often entrain debris or sediments. The high mobility and high density of the flows make them a considerable natural hazard, endangering settlements and line infrastructures. They are primarily associated with higher latitudes, e.g., Norway, Iceland, or Alaska, but they have been reported in many other countries, e.g. from the Alps. In this paper, we discuss a number of slushflow events near Atigun Pass, Alaska, which were well documented in a study for the Alyeska Pipeline Service Company (APSC) in 1982. This information has been privately held and is now being released for research purposes. This paper describes these observations, and we apply modeling techniques to the described flows. We specifically consider both depth-averaged and depth-resolved numerical methods with viscoplastic and elasto-viscoplastic rheological models. These developments can help hazard mapping practitioners better account for the hazards originating from slushflows in the future.