BILLINGS — Billings city employees have submitted sample results for interpretation from oil that contaminated the Yegen Ditch three weeks ago.
The oil originated from a buildup in a storm sewer pipe and was accidentally released when the city cleared the blockage. The original source of the oil remains undetermined as of Tuesday afternoon.
The interpretation this week could uncover whether the oil is coming from years of motor oil accumulation or a refinery leak.
"What we're gonna find out is what the oil is. Is it processed oil? Is it used oil? New oil? And that'll help us determine where we're receiving that oil from. If it's all used oil, most likely it's just buildup in the storm system from different storm events," said Derick Miller, Billings street and traffic superintendent. "If it's clean oil, we'll have to figure out where else that's coming from."
Miller maintains that the oil has not leaked into the Yellowstone River.
Related: Oil contaminates two Billings waterways, but officials say no danger to Yellowstone River
