Air emission standards set limits on the amount of contaminants which can be released to the atmosphere. These standards are expressed as a concentration in the exhaust gases leaving the stack and are capable of being accomplished using generally available incineration technology and waste diversion practices. This emission standards1 apply to existing, new or expanding solid waste incinerators operating in Nunavut and have been adopted by the Canadian Council of Ministers of the Environment (CCME) Canada-Wide Standards for Dioxins and Furans and Mercury Emissions, respectively. Similar standards for the open burning of solid waste haven’t been established.
Unit of measure is micrograms per Reference cubic metre (the volume of gas adjusted to 25oC and 101.3 kilopascals)
Opacity is the degree to which the exhaust gases decrease the transmission of light and obscure the view of any item in the background. It’s expressed as a percentage representing the extent to which an object seen through the gases is obscured. Though not an emission standard, opacity gives an indication of the overall functioning of the incinerator during ordinary operation2. Opacity in the incinerator stack shouldn’t exceed 5%. Although it is not expected that opacity levels would exceed 1% to 2% under normal operation, values greater than 5 percent indicate that the incinerator isn’t performing correctly and additional performance evaluation and adjustment is needed.
Figure 6 – Examples of Smoke Opacity Ratings
80 pg I-TEQ/cubic metre
20 µg/Rcubic metre
Equivalents per cubic metre of air
Mercury
Mercury
20 µg/Rcubic metre
Unit of measure is micrograms per Reference cubic metre (the volume of gas adjusted to 25oC and 101.3 kilopascals)
Opacity is the degree to which the exhaust gases reduce the transmission of light and obscure the view of any object in the background. It is expressed as a percentage representing the extent to which an object viewed through the gases is obscured. Although not an emission standard, opacity provides an indication of the general performance of the incinerator during normal operation2. Opacity in the incinerator stack should not exceed 5%. While it is not anticipated that opacity levels would exceed 1% to 2% under normal operation, values greater than 5% indicate the incinerator is not performing properly and additional performance evaluation and adjustment is required.
Figure 6 – Examples of Smoke Opacity Ratings
The opacity ratings are estimates and are provided for illustrative purposes only
Centre and right photos courtesy of GNWT Department of Environment and Natural Resources