On Aug 21, the Missoula City-County Health Department released preliminary findings from an inquiry into more than 80 reports from Northside and Westside residents who’ve complained for months of an odor that’s been making them feel ill. The smell has been described as similar to propane, oil or natural gas.
“This entire area is being hit,” said City-County Health Department staffer Sarah Coefield, while addressing Missoula’s Air Pollution Control Board. “Even the last week, I got several notices that it was really bad.”
Residents began reporting in April what they suspected was odor-caused nausea and sore throats. NorthWestern Energy says it hasn’t found any problems with its local transmission lines. Absent an obvious cause, health department staffers are using report times and locations, in addition to their own noses, to investigate the complaints. Coefield said she’s personally experienced the odor.
“I smelled it on Scott Street and also on the Northside,” she said.
Coefield characterized the odor as “mercaptan like.” A pungent organic gas or liquid, mercaptan is typically added to odorless natural gas and propane to aid in detection. Coefield said it is also “present in crude oil.”
According to the Agency for Toxic Substances & Disease Registry, mercaptan can cause headache, dizziness, nausea and vomiting. As Coefield told the board, not much is known about its long-term toxicity.
The health department originally tracked the Emerald Services oil recycling facility at 900 Phillips Street as a potential source of the smell. In an effort to curb emissions, Emerald installed carbon filters on its storage tanks on July 3.
After the installation, residents reported a decrease in odor severity. It returned, however, and this month the intensity is increasing. “It’s something that turns your stomach,” Northside resident Alex Metcalf told the board.
Though Emerald hasn’t been ruled out as the culprit, health department staffers say there could be others. “The railroad is also at the epicenter of this,” Coefield said. “So we can’t rule them out … This could be more than one thing.”
While officials don’t know if MRL operations are contributing to the problem, it is clear that more crude is being transported through the affected area. Last year, MRL transported eight locomotives carrying roughly 100 cars of Bakken oil from the Williston Basin. So far this year, the railroad reports transporting 37 similar shipments.
In response to questions about safety, MRL’s Mike Mattson told the board it will allow health department staffers to inspect its cargo. “Hopefully we can help get to the bottom of this,” Mattson said.
The board will next help organize a task force comprised of neighborhood residents and a department staffer to better coordinate problem-solving efforts. Next month, the health department will also secure a thermal imaging camera from the Montana Department of Environmental Quality that’s capable of detecting chemical leaks.
Metcalf said he appreciates the health department’s increasing efforts. But in light of neighborhood health concerns, the solution isn’t coming fast enough. “We can’t afford to wait another month,” he said.
The health department is asking people to report their experiences with the odor online.