Laker crewman killed by conveyor possibly mistook alarm for all-clear

A crewman performing maintenance aboard a Great Lakes ore boat was killed when he became trapped in a conveyor belt and was crushed, possibly after mistaking a door alarm for an all-clear signal.

Denton Heske, 61, of Harrison, Mich., was a deck hand on the 1,000-foot Stewart J. Cort when he got too close to a conveyor belt that was being tested, the Bayfield County, Wis., Sheriff’s Department said. The accident happened Aug. 8 while the laker sailed in Lake Superior near the Apostle Islands.

A U.S. Coast Guard boat rendezvoused with the ore carrier and transported Heske to shore, said Lt. Dan Clark of the sheriff’s department. A coroner met the boat and pronounced Heske dead of massive trauma. Coast Guard spokesman Petty Officer Brandon Blackwell confirmed the fatality.

Stewart J. Cort is operated by Interlake Steamship Co. of Richfield, Ohio. The self-unloading ore carrier, which was empty, was on a return voyage on its designated route between Superior, Wis., and the Mittal Burns Harbor docks in Indiana when the accident happened, said Tom Wynne, Interlake’s staff attorney.

Two maintenance teams were at work “literally on the bottom of the boat†when Heske was killed, Clark said.

“There were two separate projects being done at the same time,†Clark said. “One was doing some maintenance on a water-collections system, and the other was doing maintenance on a conveyor belt.â€

An outside contractor’s crew was working on the belt that offloads ore pellets. Heske, part of the ship’s crew, was servicing equipment that uses water pressure to gather pellets that fall off the belt — a system that occasionally gets clogged. The conveyor-belt group periodically needed to run the belt to test its work and used an all-clear siren to notify the ship’s crew that it was safe to approach the belt.

“That alarm system had worked very well up to then,†Clark said. “Then an alarm went off on a watertight door into the engine room. For some reason, Denton mistakes it for the all-clear siren. They were different decibel sounds.â€

Heske went back to work near the belt, unaware that it was about to move.

“Another (crewmember) said, ‘Denton, what are you doing? We haven’t gotten the all-clear,’ and he said, ‘Yes, we did — it just sounded.’ He was leaning on a roller, getting some leverage while trying to loosen one of the bolts on that water-suction system,†Clark said.

When the belt started running, “It just grabbed him and forced him between the roller and the conveyor belt,†the sheriff’s lieutenant said.

Stewart J. Cort was 10 miles north of Outer Island at the time. The laker crew immediately initiated resuscitation efforts and moved the victim to the main deck in preparation for the Coast Guard boat, which carried two emergency medical technicians, Clark said. They were not able to revive him.

Blackwell said the Coast Guard’s marine safety detachment in Duluth, Minn., is investigating the fatal accident. He declined to release further details in late September. Wynne said his company was also still investigating.

Stewart J. Cort, built in 1972, was the first 1,000-foot vessel on the Great Lakes. It is the only 1,000-foot laker with its pilothouse and crew accommodations forward, according to Interlake Steamship.

Dom Yanchunas

By Professional Mariner Staff