Personnel deployed to Nunavut's capital for Operation Nanook stayed near the four-storey pile of burning trash — known locally as the "dumpcano" after the city's fire chief compared it to a volcano of garbage.
Plumes of smoke rose from the smouldering heap for almost four months until firefighters finally doused it in September.
Documents obtained by The Canadian Press under the Access to Information Act show the military had jitters about putting its people so close to the dump fire and its nostril-searing smoke.
So it tested the air and soil around the barracks and hangars where personnel would stay for the operation. Those tests showed minimal risk to personnel.
"To date, the data collected has shown that most ambient air pollution concentrations ... have been low," says a notice from the force health protection directorate.
"However, the results indicate that the average levels of dioxins and furans continue to exceed the ambient air quality standard set by Ontario."
The province's standard is "considered to be very conservative," the directorate added, and it deemed the overall risk of dioxins and furans — chemicals produced by burning garbage, forest fires and smoking tobacco — to be low.
Nor did the military anticipate anyone would come away from the operation with anything more serious than a scratchy throat or irritated eyes from all the smoke.
As a precaution, the Canadian Armed Forces chose not to deploy pregnant women and people with lung disease or asthma to Nunavut for Operation Nanook.
The force health protection directorate also suggested having another place for personnel to stay as a back-up in case the dump fire flared up or the smoke started to bother people.
There was a good chance of that happening. Nunatsiaq News reported that the area's prevailing winds made the spot especially smoky.
The newspaper reported that city councillors rejected a proposal to use a spot along the Road to Nowhere — which winds out of Iqaluit before abruptly ending — as a fall-back because it's a favoured place for swimming and camping. However, they agreed to look at other locations.
Only a few soldiers were the worse for wear during the training exercise.
"While on Operation Nanook 14, approximately 20 deployed members reported some mild symptoms such as eye, nose and throat irritation," military spokesman Daniel Le Bouthillier wrote in an email.
"After receiving a thorough medical examination by the Op Nanook Task Force Surgeon, all members were cleared to resume their duties."
He wouldn't say if anyone had to pull out of the operation because of pregnancy, lung problems or asthma.
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