The president and CEO of the Alberta Energy Regulator, Jim Ellis, will resign early next year.
The AER says the move has been in the works for the past several months and will take effect at the end of January.
The Friday announcement comes a day after the regulator apologized and distanced itself for an internal presentation by a senior official that put the estimated liability of cleaning up abandoned energy infrastructure in Alberta at $260 billion.
Liability estimates lay out the costs of reclaiming old oil wells, pipelines and tailings ponds.
The AER news release Thursday said the $260-billion estimate was a “worst-case scenario.” The regulator said its current liability estimate is closer to $60 billion.
Ellis joined the AER in June 2013 as the first CEO of the newly formed regulator.
Prior to the appointment, Ellis served as Alberta’s deputy minister of environment from 2008 to 2011. He worked on environmental frameworks in the oilsands region, climate change initiatives and improvements to the regulatory system.
He then served as deputy energy minister.