BALTIMORE (WJZ) — The U.S. Geological Survey updated its volcano threat assessments for the first time since 2005.

Of the 161 active volcanos in the U.S., 18 are being classified as a “very high threat,”.

Mount Shasta’s in California is of particular concern because its hazards zone covers about 9,500 square miles.

Experts said more than 100,000 people live or work in that area.

An estimated 37 million cars pass by on the highway in that area each year.

The danger list is topped by Hawaii’s Kilauea, which has been erupting since May.

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