Yellowknife (Jan 05/05) - Officials recovered the body on Sunday evening of 23-year-old Gary Robinson, who was killed Dec. 29 when the plow truck he was driving broke through the ice on Prosperous Lake, about 15 kilometres from Yellowknife.

The Coroner's Office and the Workers Compensation Board have both launched investigations into the death of the truck driver.

The investigation is still in the initial stages, said Chief Coroner Percy Kinney. It could be months before officials determine the cause of the accident.

A press release from Robinson's employer said the ice road may have been weakened by unseasonable cool temperatures resulting in a condition known as "brittle" ice.

Police estimates peg the ice road thickness at between 19 and 22 inches - well above the limit for regular travel - and the company, RTL Robinson Enterprise Ltd., said road conditions are checked regularly.

"At this point we are not certain, but it may have been a bad spot," said RCMP Const. Kerri Riehl on Wednesday.

Gary Robinson was the son of company president Marvin Robinson. Gary was one of several family members involved in the business, which began as a small trucking firm in the late 1960s and grew into one of the largest companies in the territory.

"Distress and extreme shock have reverberated through the company that a valued member of our team is missing," said Larry Wheaton, director of operations for Robinson Trucking.

"Our thoughts and prayers are with Gary's family at this time."

Robinson's body was recovered by a robot submarine. He was found in 87 metres of water, too deep for a regular dive crew, whose recovery efforts were also hampered by near-freezing water temperatures.

The operator of the submersible spotted Robinson several metres from the truck, indicating he may have been able to escape the cab, but not the icy waters, Kinney said.

The accident was the "first major incident" in the 30 years RTL has been maintaining ice roads, the company said.

Robinson was plowing the private road -- which leads to a mine north of the city -- with another truck when a section of ice below his vehicle gave way at around 11 a.m. on Dec. 29.

By the time an emergency crew from the Yellowknife Fire Department reached the scene, the vehicle was completely submerged, said deputy fire chief Clem St. Croix.

Two firefighters dressed in cold water rescue suits combed the area, but were unable to locate the driver, St. Croix said.

Coroner Kinney said Robinson would only have had a few seconds to get free of the cab before water pressure outside was too great to open the door.

His escape was probably complicated by the near-freezing water temperatures, Kinney said. "The water was about two degrees Celsius. In temperatures like that, you would only have seconds."

It was the second death on a private ice road in the last four years. Heavy equipment operator Guyle Armstrong was killed in December of 2000 when his snow cat crashed through the ice near Tibbet Lake.

Armstrong was able to reach solid ground, but died from a shock-related heart attack caused by the cold water, Kinney said.

While many Northerners take driving on ice roads for granted, last Wednesday's accident highlights the dangers of crossing frozen bodies of water, said John Johansen, a service station manager with Grimshaw Trucking.

"It can happen to anybody at any time," said Johansen. "It's shocking."

He offered his condolences to the Robinson family, though he did not know Gary personally.

"When something like this happens, you can't help but feel badly," he said. A section of the ice road, which leads to Discovery Mine, was cordoned off the afternoon of the accident. Barricades with flashing lights were placed around the hole where the truck fell through.

Police are warning anyone travelling in the area to use caution. A spokesperson for the Department of Transportation said any decision to close the road would rest with the private companies responsible for its operation.

St. Croix advised motorists travelling on ice roads across the North Slave to proceed with caution. "Our policy is: ice is never safe," said St. Croix. "The thickness can be extremely variable depending on factors like snowfall and underwater currents."