By COLIN M. STEWART By COLIN M. STEWART ADVERTISING Tribune-Herald Staff Writer More than two weeks after a report on a fatal zip line accident cast doubt on the safety of other structures along the Hamakua Coast, it is unclear
By COLIN M. STEWART
Tribune-Herald Staff Writer
More than two weeks after a report on a fatal zip line accident cast doubt on the safety of other structures along the Hamakua Coast, it is unclear what is being done by the county or state to prevent such an accident from happening again.
The Hawaii State Department of Labor & Industrial Relations’ Occupational Safety and Health Division (HiOSH) released on May 29 its report on the September death of Maui resident Ted Callaway. The investigation found that the employee of GoZip LLC was killed, while another worker was seriously injured, when a zip line platform the pair were working on collapsed because the soil in which the structure’s ground anchors were buried failed to withstand the force placed on it by the load from the tower, cables and the men.
The report proposed levying penalties totaling more than $13,000 against the company that employed the men, stating that it had failed to “take reasonable precautions to assure that the anchors could support the load.”
Additionally, the report presented the results of an engineer’s soil study of the area north of Hilo where the accident occurred. He found that the subsoil in which the anchors had been placed was Pahala ash, “a fine particulate mineral that has the appearance of normal soil but loses up to 90 percent of its natural strength when disturbed,” the report stated.
The engineering report stated that much of the soil along the Hamakua Coast appears to be red dirt, but could in fact be Pahala ash, raising “serious concerns about the stability of structures that rely on ground anchors for support, including zip line towers at other locations on the island,” the HiOSH report said.
Despite the state’s findings, it is unclear how many other structures in the area utilize ground anchors or what, if anything, is being done to assure that they, too, will not collapse.
Shortly after the release of the HiOSH report last month, Department of Labor spokesman Bill Kunstman said that after completing the investigation, the state had no plans to inspect other sites.
“That’s really more up to the county at this point,” he said during a telephone interview.
Several phone calls to the county’s Building Department seeking information were not returned as of presstime Thursday.
At least one zip line operator, however, says he has taken it upon himself to test the strength of his zip lines’ platform anchors.
Skyline Eco-Adventures’ zip line course at Akaka Falls underwent a comprehensive soil analysis in November 2010 before its construction, says company co-founder Danny Boren. That study found that there was no Pahala ash where the zip lines were to be built, he said.
However, the accident at KapohoKine’s Honolii Mountain Outpost course, located just a few miles south of Akaka Falls, prompted Skyline to order an expensive test of its anchoring systems on its platforms after they were built, Boren said.
“These lines were engineered for this particular site and these particular conditions,” he said. “But, we wanted to go further and physically test the anchors on our big lines. To know. To be sure. Just because we wanted to be able to show to anyone who wanted to know that we’ve done everything we possibly could to verify our safety. There’s no better way to tell. … No one asked us to do this. There’s nobody at the state saying you have to do this.”
The tests, which cost thousands of dollars, Boren said, involved attaching cables to the massive concrete anchors buried underground and then pulling on them with a force many times stronger than the maximum load they are designed to handle. The pulling force was applied for anywhere from 10 minutes to half an hour, he added.
“They held perfectly,” he said. “There was almost no movement at all.”
Boren said that while the accident at the neighboring zip line course was a “horrible tragedy,” he felt that the focus in the media concerning the safety of zip lines on the Big Island had been “unfortunate,” in that it left the impression that all Hawaii Island operators were unsafe.
“We as a company, have done things to illustrate the fact that there are safe operators out there,” he said.
Email Colin M. Stewart at cstewart@hawaiitribune-herald.com.