A fault during routine maintenance work caused emissions to bypass Rio Tinto鈥檚 Fume Treatment Centre in Kitimat on Aug. 13, the company said.
A social media post from the company the same day said the bypass occurred after a part was replaced in the exhaust system during routine maintenance. An error during system setup prevented a backup cooling pump from activating when temperatures rose, causing the system to overheat and disrupting its ability to treat emissions.
The Kitimat Airshed Group recorded a spike in emissions around the time of the bypass, though levels remained within the 鈥渓ow risk鈥� category of the Air Quality Health Index.
The type of emissions has not yet been confirmed. Black Press Media has reached out to B.C. Works for more information.
The company explained that a bypass occurs when the system that normally cleans emissions is temporarily skipped through built-in pathways designed to prevent serious equipment damage. In this case, the failure of a backup cooling pump led to heat buildup that compromised the system鈥檚 ability to treat emissions.
Rio Tinto further clarified that what it calls an 鈥渦pset鈥� refers to the treatment system continuing to operate, but not cleaning emissions to its usual standard. Both bypasses and upsets are the result of unexpected problems during operation.
