Cleanup at the site of a Feb. 16 BNSF coal train derailment on the Fond du Lac reservation continues, according to railroad spokesperson Amy McBeth, who confirmed Wednesday that the cause of the derailment remains under investigation.

As of Feb. 27, approximately 85 percent of the coal spilled on land by the derailment of 40 train cars Feb. 16 had been recovered, according to a press release from the Fond du Lac Band of Lake Superior Chippewa, which is working with the railroad company on the cleanup.

The final parts of the coal cleanup will be the most challenging, as some of the train c...