Mount St. Helens.

Mount St. Helens.

USGS

On May 18, 1980, Bruce Nelson and Sue Ruff were camped 13 miles north of Mount St. Helens with some friends. At 8:30 in the morning, Nelson was fishing on the Green River when he saw a black cloud looming over the ridge to the south. In seconds, everything around them was black, and their mouths filled with ash.

“I started to climb through fallen trees. But it got extremely hot,” said Nelson. “I’m a baker who works with huge ovens. This was five or six hundred degrees Fahrenheit.”

The story is thrilling (Nelson, Ruff and their friends survived), but what most interested geologist Richard Waitt was the detail about the temperature. Waitt spent years after the eruption interviewing survivors in order to better understand the science of what happened on the mountain that day. He’s published a book of those first person accounts called “In the Path of Destruction: Eyewitness Chronicles of Mount St. Helens.”

We talk to Richard Waitt on the 35th anniversary of the eruption.