MISSOULA, Mont. (AP) – Crews are removing 31 mangled rail cars and more than 3,500 tons  of coal along a 200-foot section of riverbank on the Cabinet Gorge Reservoir in northwestern Montana.

The cars, each carrying about 122 tons  of coal, derailed Aug. 13 and dumped much of their contents on the south side of the reservoir, The Missoulian reported Sunday.

It took most of two days to clear the tracks and reopen them to train traffic.

Scrap and coal removal started Monday, when rail equipment and contractors arrived and loaded the first cars, Montana Rail Link spokesman Jim Lewis said.

“A large percentage of the coal has been loaded on railcars and removed from the site,” he wrote in an email to the newspaper. “The cleanup process has gone well and will wrap up shortly.”

Montana Rail Link is cooperating with the Federal Railroad Administration in its investigation. No one was injured.

Fewer than 10 tons of coal reached the river, said Kristi Ponozzo, public policy director for the Montana Department of Environmental Quality. The Federal Railroad Administration classifies coal as a non-hazardous commodity, but there has been little research into the effects of coal and coal dust on waterways.

Still, the spill did not sit well with locals who point to a history of derailments along the Clark Fork River system.

In November 2006, just 17 miles upriver, 27 loaded cars in a 115-car train traveling from Wyoming to Oregon derailed on a bridge across the river west of the town of Trout Creek. Four of the cars were initially unaccounted for and were thought to be submerged in as much as 80 feet of water.

In March, an empty Montana Rail Link coal train derailed on a washed-out section of track near the Lake Pend Oreille shore.

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