A rank odour that permeated most of Castlegar and Robson yesterday was the result of a one-time mishap at the nearby Zellstoff Celgar pulp mill, according to Celgar Environment Superintendent Fiona Mackay.
“It’s not a usual event for us – this has not happened in my recollection,” she said, explaining a noxious gas was being transferred from one boiler to another and was not supposed to vent into the air at all.
“We didn’t find any indication of a vent, so we had to look at the boiler itself,” she said, explaining that leaves two possibilities: a boiler blow-back, in which the boiler pressurized and spewed gas out, or a ruptured disk (ironically, they’re called ‘rupture’ disks, but a ruptured one is not a good thing).
“The gasses are no longer in the boiler, and we’re back to normal operations,” she said, adding the investigation into the occurrence will continue to ensure it won’t happen again. “We’re going to simulate (yesterday’s events, without the gasses) to see if we can isolate a ruptured rupture disk.”
She said the gasses in question are ones that emanate from condensate and include sulphide, methanol and turpentine – but there’s no health risk for Castlegar and Robson residents to be concerned about.
“People worry when they smell something they can’t immediately recognize as being from the pulp mill – and this was rank,” she said, adding the anomaly didn’t show up on Celgar’s community air monitoring, which indicated levels well within compliance requirements.
Hardest hit was the mill itself, where a building had to be evacuated due to the intense odour, and Mackay said Celgar staff are taking this event very, very seriously.
“The safety implications were quite huge, given the volatile nature of the gasses we’re dealing with,” she said, explaining the incident could’ve been quite worse, and the good news is, it allows Celgar the opportunity to track down the problem and rectify it without any harm or injury to workers.
The gas has now dissipated and the investigation continues into the cause of the leak.