It is a part of the Volcano Hazards Program of the United States Geological Survey, a scientific agency of the United States government.

[2] Originally, the volcano observatory was known as the Long Valley Observatory which monitored volcanic activity east of the Sierra Nevada in Mono County, California which included Long Valley Caldera, Mammoth Mountain, and the Mono–Inyo Craters.

[4] These were ranked "high threat potential":[4] These were ranked "moderate threat potential":[4] One was ranked "Low to Very Low Threat Potential":[4] Other volcanoes in the region have not been assessed at one of these risk levels that warrant monitoring.

USGS noted that though less probable it is still possible for volcanoes to erupt on longer intervals than that.

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