Practical Perspectives for Effective Odour Monitoring and Regulation

The quest for efficacious odour monitoring and regulation is formidable and increasingly pertinent to the public, regulators, and industry. In this paper, the author, an environmental lawyer, will use case studies to illuminate regulator and industry perspectives on ambient odour monitoring, address the problems associated with measuring and monitoring odours, and propose compromise positions to satisfy all parties to odour management situations.Until recent years, communities with industrial and resource companies (e.g. forestry towns and agricultural communities) accepted odours as an inevitable nuisance and byproduct of an essential industry. Today, the public has a heightened awareness of air pollution and health. Residents worry that odours from industry signal the presence of hazardous compounds. The result is that the regulator has been besieged with citizen complaints and is increasingly sensitized to odour issues.Regulators are hunting for the grail of an objective odour standard. The trend is to treat odours as any other airborne contaminant, as if an odour were a discrete chemical substance such as SO2 or NH4. This assumption is not working.The author will address the myth that odour concentrations can be measured and modelled as chemical substances. He will share his experiences with the unreliability and irreproducibility of odour measurements in the lab and field, and discuss the dire consequences that have resulted for consultants and their clients who relied on them. The author will also address the problems facilities encounter when modelling is applied to compliance and enforcement. Ontario facilities are faced with enforcement action and compliance demands based on a limit of one odour unit, derived from a modelled 10-minute average concentration of odour. One odour unit is stringent, and both measuring and modelling are complex and rife with uncertainty. Industry wants and needs a credible, quantitative approach in order to evaluate proposals for large capital projects. Once bitten and twice shy, industrialists experienced in dealing with odour control issues are reluctant to commit to achieving a modelled standard. Increasingly, we are considering whether ambient odour measurement is a more reliable indicator.The author will conclude by proposing compromise positions that could satisfy all parties to odour management situations — the generator, the sensitive receptors and the regulator that is caught in between.