Investigations on Ebeko volcano, Paramushir island are presented: microelectrotomography on a thermal field, and the results of a mercury survey in a nearby city after an ash fall. High levels of mercury vapor in the air indicate the unfavorable ecological situation of the settlement. According to the results of electrotomography, we can talk about the thermal field subsurface space: the structure of the boiling mud pots and the presence of the gas phase.