An Innovative Approach to Air Quality Management

Air quality is such an important environmental health issue that for several years now, increasingly stringent regulations have been enacted around the world. These regulations have become a major issue in many engineering projects, forcing proponents to make public commitments to comply at all times with air quality standards. However, recent experiences in both the mining and industrial sectors show that it is difficult to meet those standards by considering only a conventional approach.

In this context, it is clear that an innovative approach to air quality management is necessary. Using state-of-the-art equipment and advanced risk assessment and modelling strategies, WSP has developed an innovative approach that makes it possible to modulate industrial production according to projected weather conditions, to comply with stringent environmental standards. Specifically, production can be maximized when weather conditions are favorable for dispersal of contaminants in the air, while production is decreased during unfavorable episodes, to reduce the risk of exceedance of the air quality standards in neighboring communities of industrial facilities.

The deterioration of air quality results from the combination of air contaminant emissions and adverse weather conditions. As a result, it is highly dependent on climate change.

Climate change modifies air quality by disrupting the stability of the atmosphere at the earth's surface (wind speed, mixing height, convection, presence of fronts) as well as precipitation. The changing climate will be characterized, among other things, by an increase in atmospheric stability caused by a weakening of the global circulation. Slower wind speeds and a more stable atmosphere reduce the dispersion of contaminants, degrading air quality.

The frequency and intensity of precipitation, which can have a positive influence on air quality, is expected to increase overall. However, these variations will also cause an increase in the frequency and intensity of heat waves, causing episodes of extreme air pollution. These heat waves, associated with atmospheric blockage episodes, are difficult to predict. The study of the combination of these different climate variables determines the regional impact of climate change on the dispersion of air contaminants. It is therefore important to rigorously study these changes in meteorological models, and develop the most accurate predictions possible.

Weather forecasts have a direct impact on our daily lives. Indeed, when our weather services announce heavy rainfall, many change their plans drastically. But what we do not often consider is how these upheavals also affect companies in the industrial sector. The performance of their operations is often closely related to weather conditions. That is why one of the key components of a successful air quality management system is the compilation of accurate and detailed weather forecasts.

With this in mind, WSP has developed an air quality management system that includes automated compilation of weather conditions for the next 72 hours. Unlike data provided by our meteorological services, WSP forecasts are available hourly, allowing for more accurate industrial operations planning.

In addition, the forecasts are compiled for a specific site, thus reducing the uncertainties of the different meteorological parameters. The WSP data also include thermal inversions and atmospheric turbulence, two meteorological phenomena whose prediction is essential to ensure the reliability of air contaminant dispersion modelling.

Many experts confirm that modelling results correspond to a simplified image of reality, given the theoretical approximations inherent to the mathematical model used, and the uncertainty that surrounds the characterization of emission sources. Indeed, modelling the atmospheric dispersion of air contaminants can never completely replace samples taken in the field.

For this reason, environmental authorizations often require an air quality monitoring network involving approved methods and instrumentation that comply with regulations. For example, traditional air quality monitoring stations combined with a weather station are the most commonly used approach. But the acquisition, installation and monitoring costs associated with this equipment are significant, which limits the number of sites where these stations can be deployed.

That said, in recent years, the proliferation of new generation sensors that are small, inexpensive and easy to use has been exponential. These new technologies have the potential to revolutionize current methods of monitoring air quality. On the one hand, these types of monitors can significantly increase the spatial resolution of measurements to collect a large amount of data, facilitating air quality management decision-making for the operators. On the other hand, few tests have been done on the accuracy, precision and long-term use of these sensors. WSP is actively working to integrate these new technologies into our air quality monitoring programs in order to clearly envision the future and design for it today.

As technology evolves, our air quality management must also evolve to become more efficient. To ensure optimal management of atmospheric emissions, we will remain on the lookout for new trends in both Internet of Things (IoT) devices and artificial intelligence. Keeping up with the technologies available will allow us to stay on the cutting edge of the latest research, ensuring that we can anticipate climate shifts before they occur and engineer sustainable, Future Ready solutions to safeguard our environment.