In cities like Beijing, when a "red alert" day is called due to high air pollution levels, many restrictions come into effect including a shutdown of industrial operations that may exacerbate the problem.With the extremely high pollution levels in Kamloops over the past month, the following questions arise: To what extent do current industrial operations like those engaged in by the Domtar Pulp Mill contribute to these high levels, and do their operations makes thing worse during emergency situations like this?This is a very difficult question to answer completely, and without full access to provincial air quality data I can only make some inferences and educated guesses.Here's what I have seen, and this suggests that a lot more work is needed on these questions.First, we began seeing a spike in PM2.5 levels around July 8 in Kamloops. PM2.5 levels can come from a variety of sources including pulp operations, traffic, residential wood burning practices, slash burning, and of course forest fires. In the past, the PurpleAir network that I setup in Kamloops showed very big spikes in PM2.5 levels that coincided with visible pollution from Domtar plus notable sulphur smells that come from its processing operations. There is no doubt that Domtar can rapidly spike PM2.5 levels in Kamloops, and provincial air pollution readings for Total Reduced Sulphur confirm that this is primarily (if not exclusively) from this polluter.Second, Total Reduced Sulphur emissions are not associated (as far as I can see in the literature) with forest fires themselves. They come from industrial processes and also from municipal sewers and sewage treatment plants as well as swamps, bogs and marshes.Preliminary analysis [based on Kamloops Federal Building Air Monitoring Station: "Contains information licensed under the Open Government Licence – British Columbia."If we look at PM2.5 (hourly averaged) data from July 31-August 7 and Total Reduced Sulphur (hourly averaged) data for the same time period, it seems clear to me that the contribution of Domtar to the current pollution situation from forest fires is significant.The peaks on August 3, 5, 6 and 7 overlap almost perfectly with little latency between PM2.5 levels and Total Reduced Sulphur. Since Domtar is likely emitting PM2.5 at the same time as Total Reduced Sulphur, it is reasonable to conclude that these very high levels (especially the unprecedented spike on August 3) are a combination of Domtar emissions and forest fires.
If so, it only makes sense to immediately shutdown such industrial operations to avoid creating a compounded problem."