title: Site specific risk assessment of an energy-from-waste/thermal treatment facility in Durham Region, Ontario, Canada. Part B: Ecological risk assessment.
abstract: The regions of Durham and York in Ontario, Canada have partnered to construct an energy-from-waste (EFW) thermal treatment facility as part of a long term strategy for the management of their municipal solid waste. In this paper we present the results of a comprehensive ecological risk assessment (ERA) for this planned facility, based on baseline sampling and site specific modeling to predict facility-related emissions, which was subsequently accepted by regulatory authorities. Emissions were estimated for both the approved initial operating design capacity of the facility (140,000 tonnes per year) and the maximum design capacity (400,000 tonnes per year). In general, calculated ecological hazard quotients (EHQs) and screening ratios (SRs) for receptors did not exceed the benchmark value (1.0). The only exceedances noted were generally due to existing baseline media concentrations, which did not differ from those expected for similar unimpacted sites in Ontario. This suggests that these exceedances reflect conservative assumptions applied in the risk assessment rather than actual potential risk. However, under predicted upset conditions at 400,000 tonnes per year (i.e., facility start-up, shutdown, and loss of air pollution control), a potential unacceptable risk was estimated for freshwater receptors with respect to benzo(g,h,i)perylene (SR=1.1), which could not be attributed to baseline conditions. Although this slight exceedance reflects a conservative worst-case scenario (upset conditions coinciding with worst-case meteorological conditions), further investigation of potential ecological risk should be performed if this facility is expanded to the maximum operating capacity in the future.
authors.affiliation: Intrinsik Environmental Sciences Inc., 6605 Hurontario Street, Mississauga, ON L5T 0A3, Canada. Electronic address: collson@intrinsik.com.
authors.forename: Christopher A
authors.initials: CA
authors.lastname: Ollson
authors.forename: Melissa L
authors.initials: ML
authors.lastname: Whitfield Aslund
authors.forename: Loren D
authors.initials: LD
authors.lastname: Knopper
authors.forename: Tereza
authors.initials: T
authors.lastname: Dan
mesh_terms: D000818:Animals; D003246:Conservation of Energy Resources; D004781:Environmental Exposure; D004784:Environmental Monitoring / Q000379:methods*; D004785:Environmental Pollutants / Q000633:toxicity*; D009864:Ontario; D010944:Plants / Q000187:drug effects*; D018570:Risk Assessment / Q000379:methods; D014714:Vertebrates / Q000378:metabolism*
chemical_list: D004785:Environmental Pollutants
keywords: ADD; COPC; CR; EA; EFW; EHQ; EPC; ERA; Ecological risk assessment; Energy-from-waste; Environmental assessment; HHRA; Incineration; LC50; LD50; LOAEL; LRASA; NOAEL; SAR; SR; TRV; Thermal mass burn technology; UP; Waste management; average daily dose; concentration ratio; contaminant of potential concern; energy-from-waste; environmental assessment; environmental hazard quotient; environmental risk assessment; exposure point concentration; human health risk assessment; local risk assessment study area; lowest observed adverse effects level; median lethal concentration; median lethal dose; no observed adverse effect level; screening ratio; species at risk; toxicity reference value; uptake factor