 Along with volcanoes associated with recent earthquake activity, a scenario of an eruption at Mount Cayley in southwestern British Columbia illustrates how Western Canada is in danger to a volcanic eruption, which has not erupted for at least 310,000 years.This impact is becoming even more likely as population in the Pacific Northwest increases and development spreads.The scenario is based on former eruptions in the north-south trending Garibaldi Volcanic Belt and includes both explosive and passive eruptions.