NWT Air Quality Report (2011) - Environment and Natural ...

Coarse Particulate (PM 10)The maximum daily average measured from the PM 10BAM in Inuvik in 2011 was 96.3μg/m 3 ,recorded in May. The highest hourly maximum was 308.4μg/m 3 and occurred in July. Therewere 15 exceedances of the adopted 24-hour standard (50µg/m 3 ), which generally occurredin the snow-free months. Similar to previous years, the spring-time levels were elevated andwere representative of the typical ‘spring-time dust event’ associated with residual wintergravel. Given the dirt roads in the Inuvik area in proximity to the monitoring station, the dustevents can persist into the summer months as well.Figure 14: 2011 Inuvik BAM PM 1040.0(μg/m 3 )200.0Monthly Average35.030.025.020.015.010.05.0180.0160.0140.0120.0100.080.060.040.020.0Maximum Daily Average0.0J F M A M J J A S O N D0.0Monthly AverageMaximum Daily AverageFigure 14 shows the monthly averages and the maximum daily average concentrationsof PM 10from the BAM in Inuvik. The spring spike is attributed to the residual winter gravelon the roads following the thaw, while the summer elevations are likely attributed to acombination of the forest fires burning in the Inuvik area in June, July and August, and thepresence of dirt roads in proximity to the station.20 NWT Air Quality Report 2011