Over 30 underground coal fires burn in Colorado. Between 2011 and 2013, Koveva Ltd. performed a high-order characterization of these fires to determine their activity levels. Field surveys including gas composition analysis, isotope analysis, magnetometer surveys, surface mapping, surface methane seeps, and snowmelt mapping, among others, were conducted. Results from these characterizations allowed Colorado’s Division of Reclamation, Mining and Safety to prioritize implementation of fire control methods. Data and analyses from this work are currently being used to assist the State design optimal fire control methods.