Castonguay Decision: when in doubt, report

November 26, 2013 | John R. Tidball

On October 17, 2013, the Supreme Court of Canada released its decision in Castonguay Blasting Ltd. v. Ontario (Environment).  Miller Thomson’s Bruce McMeekin and Andrea Farkouh represented Castonguay before the Supreme Court. The decision confirms the extraordinary scope of the reporting duty in Ontario’s Environmental Protection Act (EPA).

The facts were not in dispute.  In controlled blasting to widen a provincial highway, “flyrock” travelled about 90 metres through the air and damaged a house and a car.  The incident was reported to the Ontario Ministries of Labour and Transportation, the cause was investigated and corrective measures were taken before blasting resumed. Castonguay compensated the property owners for all damage.

Six months later, the Ontario Ministry of the Environment (MOE) learned of the incident and charged Castonguay with failing to report forthwith to the MOE about the discharge of a contaminant into the natural environment that was out of the normal course of events and that caused an adverse effect (i.e. property damage). Castonguay was acquitted at trial. The acquittal was reversed on appeal to the Superior Court of Justice. The conviction was upheld by the Ontario Court of Appeal in a split decision and by the Supreme Court of Canada.

The decision turned on an interpretation of section 15 of the EPA, specifically relating to whether some impairment of the quality of the natural environment is necessary before an effect from a discharge is an “adverse effect”.  The Supreme Court held that an adverse effect need not contain any impairment of the quality of the natural environment, so that property damage on its own may be sufficient to trigger the section 15 duty to report. In the words of Justice Abella, writing for the Court, “the Ministry of the Environment must be notified when there has been a discharge out of the normal course of events without waiting for proof that the natural environment has, in fact, been impaired.  In other words: when in doubt, report.”

The Supreme Court’s decision seems likely to prompt an increase in the number and type of incidents reported to the MOE. For example, one of many other “non-environmental” incidents raised in argument before the Supreme Court was a truck losing a tire on a highway and causing property damage to other vehicles.  The tire is a “contaminant”.  Losing a tire is “out of the normal course of events”. The tire travels through the “natural environment” to cause damage to other vehicles, an “adverse effect”.  The Supreme Court’s decision in Castonguay suggests that the truck driver has a duty to forthwith report to the MOE. 

In 1998, faced with significant over-reporting of spills by industry already educated to report when in doubt, the Ontario Government promulgated a regulation aimed at reducing the number of spills reported.  (The duty to report the spill of a pollutant under section 92 of the EPA is a companion requirement to section 15, although its scope is much narrower). There is no indication that the MOE has any plans to narrow the scope of the section 15 reporting duty through any new regulatory exemptions. As a result, in the words of Justice Blair of the Ontario Court of Appeal, the MOE may now be the Ministry of Everything


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