Air Emissions from Ashbridges Bay Treatment Plant

1. Air Emissions fromAshbridges Bay Treatment Plant By Anthony Ciccone, Ph.D., P.Eng. –Golder Associates Ciara De Jong, MES –Golder Associates Angela Li-Muller, Ph.D. –Toronto Public Health Mark Rupke, P.Eng. –WES Diane Michelangeli, Ph.D. –York University Jean Yves Urbain, P.Eng. –Earth Tech Policy Analysis Tools for Air Quality and Health 19 May 2005

2. Objective of Emission Study • Evaluate the past, current and future impacts of air emissions South Riverdale and Beach Communities

3. Methodology • Data collection and review • Plant process information (including previous studies) • Ambient air monitoring data • Meteorological data • Develop an air emission inventory • Determine chemicals released • Location of releases • Stack and area characteristics • Mass emissions into air • Process meteorological data • Build input data for CALPUFF • Select 17 chemicals for modelling • Model chemical impact on communities • Analyze results

4. CALPUFF The Modelling Process Emissions Concentrations Meteorology Receptors

5. ABTP Historical Scenarios • Incinerator was in full operation (pre-1996) • Incinerator was in partial operation (2000-2002) • After incinerator was discontinued (2003-2004) • After incinerator was discontinued and odour control fully implemented (by 2010)

6. Concept Plan for Key Plant Areas

7. Protocol to Select Chemicals • Prioritize chemicals • Ranking • Method 1a - Calculated Toxicity Equivalent for Cancer effects • Method 1b - Calculated Toxicity Equivalent Non-Cancer effects • Method 1c - Ranked chemicals based on toxicity, emissions, persistence, and bioaccumulation • Select top 25 from rankings • Above laboratory detection limits • Important to communities

8. Arsenic Benzene Benz[a]pyrene (B[a]P) Bis(2-ethylhexyl)-phthalate Cadmium Di-n-octyl phthalate Hexachlorobutadiene Hydrogen sulphide Lead Mercury Nitrogen oxides PM2.5 PCBs Sulphur dioxide Total dioxins and furans Total polyaromatic hydrocarbons (PAHs) Vinyl chloride 17 Chemicals Modeled

9. Hydrogen Sulphide24 Hr Concentration Isopleths AAQC – N/A ug/m3 Health Benchmark – 10 to 2 ug/m3

10. Summary of Impacts on Communities

11. Conclusions - 1 • Little difference between air quality on South Riverdale vs Beaches due to ABTP • Elevated stack has slightly higher impact to the northeast because of high velocity winds from the southwest • Low elevations sources have higher impact to the northwest because of lower velocity winds from the southeast

12. Conclusions - 2 • Significant process changes since 1995 has changed the ABTP air emission profile • Removal of incineration eliminated • arsenic, • cadmium, • lead, • PCBs, and • Dioxins/Furans

13. Conclusions - 3 • Compared to Toronto Ambient Air While Incinerator Operating • Predicted maximum levels below Toronto measured ambient levels

14. Conclusions - 4 • 15 chemicals were unequivocally detected at ABTP • All detected chemicals below MOE air quality criteria/standards for all time scales

15. Conclusions - 5 • Most detected chemicals below health benchmarks except • Hydrogen Sulphide above the lower chronic limit (2 ug/m3) for some scenarios • Cadmium exceeds only during incineration • By 2010, all detected chemicals meet health benchmarks • All detected chemicals below Toronto measured levels during incineration

16. Conclusions - 5 • Benzo[a]pyrene/PAHs less than detection limits • At B[a]P detection limits, • Health benchmark exceeded for all scenarios • MOE air quality criteria will be met by 2010 • Maximum predicted impact was greater than measured • Impact over estimated