Lessons learned from oil sands monitoring, results report 2013 to 2014
3. 2013 to 2014: what we have learned in year 2
Monitoring and scientific study data continue to show evidence that oil sands development is creating low-level changes on the surrounding environment. Substances of concern include polycyclic aromatic compounds, particulate matter, acidifying compounds and metals in air, water, biota, snow and sediments. While the concentrations of substances found in the environment are generally not at levels that are cause for concern, monitoring will continue to track, evaluate and report any changes or trends. Generally, the concentrations of these substances are highest at locations close to oil sands extraction and upgrading facilities, and they decrease to background levels within roughly 50 km. The biodiversity in the oil sands region remains mostly intact, with a Biodiversity Intactness Index (a biodiversity measure in developed areas relative to undisturbed areas) for the oil sands development area of 91% in the active in-situ region, and 86% in the surface mineable region.
Some specific examples of monitoring observations from the past year include:
- Hourly average measurements of total gaseous mercury made in air in Fort McMurray have not shown significant changes over time, and the observed concentrations are similar to those found elsewhere in Canada.
- Naturally high sediment loads reflecting erosion during the spring and summer cause total metal concentrations in the Athabasca River to exceed the Canadian Council of Ministers of the Environment (CCME) guidelines in these seasons.
- Total phosphorus and nitrogen exceeded the Alberta surface water quality guidelines during periods of naturally high loads of suspended sediment-related precipitation-induced erosion.
- Some wetlands water samples had iron and cadmium concentrations that exceeded established (CCME) safe limits for aquatic life, although there is no spatial pattern associated with proximity to development.
- Some lakes were found to have major ion concentrations that exceeded CCME guidelines, although these observations are consistent with what is known about the underlying geology, with no spatial pattern associated with proximity to development.
- Snowpack data continue to be consistent with past results and show deposition concentrations of polycyclic aromatic hydrocarbons and metals (As, Ag, Be, Cd, Cr, Cu, Hg, Ni, Pb, Sb, Se, Tl, Zn) at low concentrations that decrease with increasing distance from oil sands operations.
- Zooplankton (tiny invertebrates that float freely throughout freshwater) in lake sediments from the oil sands region show increases in primary productivity of biomass that may indicate climate-induced increases in light and temperature, and/or the addition of nutrients.
- Tree swallows from near oil sands operations showed signs of being exposed to atmospheric contaminants, yet exhibited normal reproductive success, and their nestlings were observed to be healthy.
- Species that prefer old-forest habitat, like the marten, fisher and bay-breasted warbler, were found to be less abundant than would be expected in an undisturbed area. In contrast, species that thrive in areas with human development, such as the coyote and song sparrow, have higher abundance than would be expected in an undisturbed area.
The data for these results, along with relevant context, are all available on the Portal and from monitoring organizations such as the Wood Buffalo Environmental Association, Lakeland Industry and Community Association and the Alberta Biodiversity Monitoring Institute.
Integrating monitoring results
Results from two key classes of compounds are summarized below to demonstrate the initial steps in integrating monitoring data from air, water, wildlife health and biodiversity.
Polycyclic aromatic compounds
Polycyclic aromatic compounds (PACs) are a group of many different substances formed by the incomplete burning of organic substances (oil, gas, wood, food, tobacco, etc.) and are natural components of petroleum deposits. These compounds often attach to dust particles in the air, do not dissolve easily in water, and can be deposited in soils or sediments. Exposure for animals and birds is usually through breathing, although humans may ingest these compounds through consumption of charbroiled foods.
PAC measurements in air, and in air particles, precipitation, snow, bulk deposition and sediment cores, are being compared to assess and predict the transport and deposition of PACs, including quantifying linkages to potential environmental effects. These data sources include:
Tailings ponds : Concentrations of 16 priority polycyclic aromatic hydrocarbons (PAHs, a subset of PACs) found in tailings pond water suggest that evaporation of PAHs can be a more significant source of atmospheric PAH concentrations than previously recognized. Measuring emissions from tailings ponds has proven to be complex and challenging. Work continues with the industry operators to have better information on potential emissions from the tailings ponds.
Air : Concentrations of all PACs decreased with distance from oil sands development operations, including for the alkylated-PAHs (a type of PAH generally created in the formation of oil deposits).
Snowpack : Snow samples and lake sediment core samples of PACs from 2012 at approximately 90 sites are time-integrated measurements showing that concentrations decreased with distance from the major mining extraction and upgrading facilities.
Sediment : PACs in lake sediment cores collected from lakes located at a distance of 30 to 185 km from the major oil sands development area provide evidence of atmospheric deposition of PACs going back as far as 100 years. Lakes closer to oil sands mining activities show PAC deposition has increased over time and can be associated with mining activities. Concentrations are below CCME sediment quality guidelines (where they exist) except in one lake immediately adjacent to the development area and are low compared with semi-rural lakes near Edmonton.
Water : For samples collected from the Athabasca, Peace and Slave rivers, concentrations of PAHs were generally well below the guideline levels (where guidelines exist).
Additional work is ongoing to determine PAC levels found in benthic invertebrates, colonial waterbirds, waterfowl and commercially trapped fur-bearing animals.
Mercury
Monitoring of mercury is under way to understand whether the oil sands industry is a significant contributor of mercury in the region. It is well understood that mercury deposition is a global issue due to the increase in coal-fired power generation in Asia and the transboundary movement of mercury. Mercury can also be introduced into water systems from natural changes in water flows and possible flooding. The monitoring in the region helps to understand the potential human health exposure concerns and assist health authorities in their assessments. In the oil sands region, mercury is measured in air, snow, water and selected wildlife, and compared to assess and predict the transport, deposition, and transformation of mercury, including quantifying linkages to potential environmental changes. These data sources include:
Air : Total gaseous mercury (TGM) concentrations at select air monitoring sites in the oil sands region are comparable to sites across Canada. TGM concentrations are higher in the spring and midday, and low in the fall and early morning. Forest fires tend to increase TGM concentrations, as does long-range transport by wind from the southeast and west. Lower TGM concentrations were generally a result of air transported into the region from the Arctic. The first concentration measurements of the different types of atmospheric mercury are now available and will help elucidate the complex mechanisms of how mercury cycles through the environment through transport, transformation and deposition processes.
Snowpack : Monitoring of atmospheric deposition from 2011 to 2013 recorded in snowpack showed low levels of mercury and methyl mercury, comparable to concentrations in undeveloped areas in northwestern Ontario. Concentrations decrease to background at 50 to 100 km from development sites.
Water : Tributary river water sampling for total and methyl mercury indicates that concentrations generally increase during the high-flow period (along with other metals). With a few exceptions, levels measured are below guidelines. Future data will indicate whether there is a variation in concentrations along the length of the river.
Effects : In the Peace-Athabasca Delta, most colonial waterbird eggs did not show any change in methyl mercury concentrations over the period for which data exists. Methyl mercury in eggs from one species of gull in the Peace-Athabasca Delta was found to be slightly higher in 2012 than observed in years earlier. In 2013, mercury levels in western Lake Athabasca were similar to 2012, with the exception of levels measured in the eggs of Caspian Terns. Data suggest that dietary change, long-range atmospheric transport of mercury and forest-fire-related mercury emissions are not contributing to the observed levels of mercury in gull and tern eggs in northern Alberta. While no applicable guidelines exist for these measurements, expert assessment is that the observed levels of mercury are not likely to pose a risk to these bird populations. Efforts to monitor mercury levels in colonial waterbird eggs continue.
Monitoring mercury in river and lake sediment, invertebrates, fish, amphibians, and hunter-harvested birds and mammals is well under way, and data and results will follow.