The recent conviction of Unimin Canada Ltd (R v Unimin Canada Ltd, 2015 CarswellOnt 11640) underscores again the potential regulatory costs of failing to take appropriate  preventative measures to ensure compliance with the Environmental Protection Act, RSO 1990, c E.19 ("EPA")–even during unusual weather.

Unimin operates an open-pit Nepheline Syenite mine and related processing facilities near Kasshabog Lake near Havelock. Nepheline is a non-toxic mineral used in the manufacturing of various products, including glass and ceramics.

The company had a Dust Management Plan in place. However, as a result of an unusually warm winter, followed by an abnormally warm and dry spring, these measures proved insufficient in preventing dust, in the form of dry tailings materials, from blowing out of Unimin's open tailings storage.

Between March and November 2012, neighbouring residents complained of excess dust blowing from the Unimin facility onto their properties and coating outdoor furniture, vehicles, and homes. They reported experiencing various adverse effects, including loss of enjoyment of the normal use of their properties.

As a result, the company was charged with failing to take all necessary steps to prevent emissions of dust into the natural environment that were likely to cause an adverse effect.

In conjunction with the Ministry of Environment and Climate Change ("MOECC"), Unimin undertook "extensive" and costly (apparently totalling $1,675,000) mitigation and preventative measures beginning in March 2012 to get the dust emissions under control.

Even given these extensive, expensive, and cooperative efforts, Unimin was ultimately fined $325,000, plus victim surcharge (the company had a prior conviction under the Ontario Water Resources Act, RSO 1990, c O.40).

The case serves as yet another reminder that when it comes to EPA compliance, an ounce of prevention is worth a pound a cure. It also hints at an evolving relationship between due diligence and planning for abnormal weather events in the era of climate change. As "unusual" or "extreme" weather events increasingly become the norm, exercising due diligence will require enhanced planning.

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