Photos of hot springs and fumaroles – photos '9-67' (1931) and '9-56' (date unknown) – show hydrothermal activity prior to power-generation. It is unknown if those smaller hydrothermal surface features are still active as of 2015, post-power plant development; field reconnaissance would be required to assess the activity of the hydrothermal features. Photos '9-69' (close-up, date unknown) and '9-108' (distant, 1971) show the uncapped well that is not a natural geyser, which was active prior to power-production. Geyser activity at the wellhead ceased circa 1985/1986 as the local dual-flash geothermal power plant began operations.