A fire at ExxonMobil refinery east of Billings sent heavy, black smoke over portions of Lockwood on Friday.
ExxonMobil said the 8:25 a.m. fire occurred in the refinery’s fluid coker unit, where heavy hydrocarbons are heated to 975 degrees so more marketable, lighter petroleum products can be cooked out.
No one was injured.
“It was a small leak that caused the fire. Our emergency response team immediately responded to that. All of our workers were accounted for and there were no injuries,” said Jill Quade, ExxonMobil refinery human resources manager. “There were no off-site impacts.”
The ExxonMobil fire was the second refinery occurrence in less than a week for Billings. There was a non-injury fire Wednesday afternoon at Phillips 66.
Low-hanging, black smoke from the ExxonMobil fire drifted south from the refinery toward a residential area in Lockwood for a few hours.
Quade said she didn’t know what was in the smoke. At the site of the fire there was no exposure to hazardous chemicals.
Air pollution is measured by opacity, meaning whether light can pass through it. Based on ExxonMobil reports, state Department of Environmental Equality officials say the opacity of the fire pollution was 100 percent at 9 a.m., meaning the smoke completely blocked light. By 11 a.m., the opacity was 40 percent and ExxonMobil informed DEQ it would be a couple more hours before the refinery could cut opacity to the maximum acceptable level of 20 percent.
“Anytime you have 100 percent opacity, whether it’s coming off of a smokestack or coming off a dirt road, you don’t want to be breathing that,” said Bob Gallagher, DEQ environmental engineer. “Try to avoid it.”
High-opacity air pollution can be particularly irritating to young children, the elderly and people with breathing conditions. Smoke from the Friday morning fire drifted south, thinning to a brown haze over homes along Greenwood Avenue.
The fire was the second time in 12 hours that ExxonMobil exceeded opacity limits. The refinery self-reported a problem with sloughing coke Thursday night at about 9 p.m. that produced excessive air emissions for about six minutes.
ExxonMobil refinery will submit to DEQ a report on the excess pollution, along with any preventive steps it will take in the future.
The ExxonMobil refinery is a 60,000 barrel-a-day facility with 260 employees and roughly 100 subcontracted workers.
It has been operational since 1949.