By Terry Lam, P.Eng
Q: How does my facility show compliance with the MOECC standards? Is outdoor monitoring involved?
Compliance is demonstrated by preparing an Emissions Summary and Dispersion Modelling (ESDM) report meeting the requirements of O. Reg. 419/05. This report includes an estimation of the emissions released from the facility and predicts the off-property concentrations using a computer program called a “dispersion model.” The model results are compared against applicable standards to show compliance. It is not practical to show compliance using off-property monitoring since this can only be done at a limited number of locations for a limited period of time and is quite expensive. Compliance must be demonstrated at all points off-property under a large range of meteorological conditions which necessitates the use of a model over a monitoring program. It should be noted that O. Reg. 419/05 considers a modelled or exceedance of a standard to have the same impact as a monitored or measured exceedance for most contaminants.
Q: How are emissions from my facility quantified? Will sampling and analysis be required?
A: There are several methods that might be used to estimate emissions. Site-specific sampling, while potentially providing the most accurate estimate, is also very expensive and can drive the cost of the approval project up substantially. Generally, more conservative estimates are made based on emission trends published in literature (called “emission factors”) if available. Emission factors are often derived from sampling results at similar sources. Emissions may also be estimated using engineering principles and process information, or a materials mass balance. The general approach is to start with the assessment with cheaper, but more conservative methods to estimate emissions and move towards more accurate methods if required. This approach helps ORTECH control the costs of the project. If source sampling is required, ORTECH maintains one of the largest and most experienced teams in Canada to provide assistance.
