Tacoma scientist dies while on trek to Mount Everest base camp

Lisa Berntsen, a Tacoma environmental scientist, died recently while on a trek to Mount Everest’s base camp, The Mountaineers announced Thursday on its website. She was 49.

According to the statement, Berntsen died as the result of “a sudden and unexpected medical event.” The experienced outdoorswoman who led outings for the Tacoma branch of The Mountaineers, an outdoor nonprofit organization, was on a trip with Mountaineers Global Adventures.

Berntsen, a University of Washington graduate, worked for Tacoma’s GeoEngineers since 2003. She was also on the board of directors and treasurer for Braided River, a nonprofit affiliated with Mountaineers Books.

“We are all stunned by the loss of such a cherished and beloved member of our community,” Mountaineers executive Martinique Grigg wrote in the statement published on the group’s website. “Lisa was a close friend and colleague to many of us and made deep and lasting contributions to The Mountaineers at every level of the organization.”

Berntsen is survived by her husband, Royce Poetter, and daughter, Alicia Stephens.