Greg Franta, who had been missing for more than a month, apparently died when his Honda Civic hybrid fell down a 100-foot embankment off Colorado Highway 93, west of the Arvada Reservoir.

The Colorado State Patrol made the announcement yesterday, according to the Daily Camera, ending a search for the Boulder architect, a green-building pioneer who worked with former President Bill Clinton to make the White House more energy efficient.

Franta, 58, the senior vice president for the Rocky Mountain Institute, did not show up for work last month after dining the night before with a family member. Franta has worked on projects across Colorado and around the world, and was even spearheading the building of Democracy Now!‘s new studio in New York City.

“It was really crushing,” said Michael Kinsley, a senior consultant in RMI’s Snowmass office who worked closely with Franta (via the Aspen Daily News). “People were crying and it was real sad.”