A state investigation of an accident that killed a Hawaii island zip line employee in September has found a tower collapsed because it was anchored in soil that could not withstand the load.

The Hawaii State Department of Labor & Industrial Relations Hawaii Occupational Safety and Health Division said today in a news release that proposed penalties against zip line operator GoZip LLC total $13,500, and that the company has been cited for "failure to do everything reasonable and necessary to protect the life, safety, and health of employees by not assuring that the ground anchors and guy cable system … could support the loads imposed by the tower, zip lines, and weight of human riders without failure," among other violations.

"For zip line installers, this tragic accident demonstrates the importance of basing design and construction decisions on measurable objective information, for the safety of workers as well as the general public," DLIR Director Dwight Takamine said. "Unfortunately, this is another workplace fatality that was preventable and we share the sorrow of the family, friends, co-workers and others affected by this incident." 

GoZip employee Ted Callaway was killed when he fell 100 feet into a gulch. Another worker, Curtis Wright, was injured when he fell 30 feet from the tower on Sept. 21. Employees were adjusting and testing cables on the zip line along the Honolii Stream above Paukaa.