Carolyn will speak about the geology/history/hazards/impact of the exchanges at the Nevado del Ruiz and Mount Rainier volcanoes, which have twin catastrophic lahar histories and hazards. In Colombia, we have had many conversations with first responders and survivors of the 1985 lahar disaster, and they have motivated US officials to double down on local efforts. Our emergency management technologies and coordination inspire the Colombians. The experiences have transformed me, as well as the official preparedness efforts in both nations. More complete abstract and bio details to follow. This will be a Zoom broadcast—Stay tuned.