Originally from Norway, Espen Jervsjo has lived in Manley Hot Springs, Alaska for twenty years where he has done a lot of traveling on the Tanana River in the winter. He has been a trapper and since 1997 has set trail for the Iron Dog Snowmachine Race. According to Espen, he drives thousands of miles each year on his snowmachine on the river. He has come to understand the challenging ice conditions that develop on the lower Tanana River from Manley to Tanana and knows how to be safe when traveling. Espen showed members of the Dangerous Ice Project team specific dangerous locations on the Tanana River below Manley on a March 1, 2010 fieldtrip and in an interview (Oral History 2011-07-02).