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Ontario industries don’t seem worried enough about proposed changes to Ontario Regulation 419/05, EBR  registry number 010-6587. These apparently minor, technical amendments to the air standards regulation will make it much easier for the Ministry of the Environment to find industries out of compliance, even if their emissions do not change, and could make it much harder to obtain future certificates of approval.

For example (with thanks to Boris Weisman):

Section 10 of Regulation 419 already makes finding the maximum POI very difficult. As the maximum POI is not necessarily produced by the maximum emission rate for a complex facility, MOE requires that proponents evaluate a wide range of operating scenarios. Since it is not known beforehand which combination of emission rates from the various units will result in the maximum POI, MOE requires proponents to test all possible combinations. For advanced models which require long processing times, this can make the task almost unmanageable.

The proposed amendment would enormously complicate this already difficult task, multiplying the theoretical combinations by variations in the startup, shutdown or malfunction of every source on a site. In a complex facility where many processes are implicated in the start-up, with alternative staging possibilities, the number of potential combinations is immense. This makes the modeling process hugely expensive and time-consuming. This additional effort often produces no relevant information – for example, where the POI is driven by fugitive sources.

Even where major sources are the principal determinants of POI, the proposed methodology will predict emissions that will almost never occur. The proposed amendment, along with the requirement to model 5 years of hourly meteorology, will result in emission predictions of what would happen if the worst possible temporary operating conditions occurred during the worst hour’s weather in five years. For example, if a one hour upset can happen once per year and one hour of extreme unfavourable weather can occur 1% of the time, then the probability of the predicted POI is 1 in a million. If that wildly improbable event is the benchmark for measuring compliance, industrial facilities in urban locations will rarely if ever “comply”.

As the air standards in regulation 415/05 are being phased in slowly, many industries may not yet be aware of the pitfalls they contain. The comment period expires next week, September 8.

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