Guideline A-7 was originally published in 1996. Previous updates have included incorporating more stringent emission limits for dioxins and furans (2001), and for mercury (2000), compared to those of 1996.
More stringent emission limits for cadmium, lead, nitrogen oxides, particulate matter as well as dioxins and furans are now being proposed in this revision of the Guideline A-7. The proposed emission limits for cadmium, nitrogen oxides and particulate matter are the same as those adopted by the United States for new large municipal waste combustors in 2006. The proposed emission limit for lead is more stringent than the current United States standard.
The proposed emission limit for dioxins and furans is the Level of Quantification (LoQ) as defined by Environment Canada.
Air Emissions in Ontario are regulated by the Ontario Regulation 419: Air Pollution - Local Air Quality. Regulation 419 sets air standards as "point-of-impingement" limits with a goal of protecting the most sensitive receptor. The proposed emission limits in the Guideline are source emission limits, or in-stack limits, that apply to individual municipal waste thermal treatment facility stacks. They are based on the principles of Maximum Available Control Technology (MACT) or in the case of dioxins and furans on the Lowest Achievable Emission Rate. Compliance with in-stack limits of Guideline A-7 will ensure protection of human health and the environment to a higher degree than compliance with the “point-of-impingement” limits of Ontario Regulation 419/05.
Emission testing has demonstrated that existing municipal waste thermal treatment facilities equipped with modern process and air pollution controls are capable of achieving these more stringent emission limits.