The Environmental Impact Statement for Alberta tar sands production ignored a major air pollution pathway, underestimating the damage to the environment.
Our study shows that emissions of polycyclic aromatic hydrocarbons estimated in environmental impact assessments conducted to approve developments in the Athabasca oil sands region are likely too low. This finding implies that environmental concentrations in exposure-relevant media, such as air, water, and food, estimated using those emissions may also be too low. The potential therefore exists that estimation of future risk to humans and wildlife because of surface mining activity in the Athabasca oil sands region has been underestimated.
Despite taking into account PAH emissions from stacks, mine vehicles, mine faces, plant fugitives, and tailings areas, the estimated EIA emissions were insufficient to explain contaminant levels measured in the environment. This insufficiency may be because the EIA estimates zero emissions of all PAHs except naphthalene from tailings areas, plant fugitives, and mine faces, an unrealistic estimation considering the oil sandsMoreover, the evaporation of PAHs from tailings is an additional pathway for long-distance water pollution.
extraction and upgrading processes. The extraction and upgrading processes, which involve mixing with water at high temperatures in addition to aeration and thermal cracking, should facilitate the transfer of even higher molecular weight PAHs to the gas phase.
These inconsistencies suggest major alteration is required in the methodology used to estimate PAH emissions from different sources in environmental impact assessments, (my bolding) such as that described in ref 42.
Accounting for evaporative emissions (e.g., from tailings pond disposal) provides a more realistic representation of PAH [polycyclic aromatic hydrocarbons] distribution in the AOSR [Athabasca oil sands region]. Such indirect emissions to air were found to be a greater contributor of PAHs to the AOSR atmosphere relative to reported direct emissions to air. The indirect pathway transporting uncontrolled releases of PAHs to aquatic systems via the atmosphere may be as significant a contributor of PAHs to aquatic systems as other supply pathways.This report casts a shadow of doubt on the recent U.S. Department of State EIS determination that Keystone XL would have minimal environmental impact.
Simon Dyer, director of Alberta and the north for the Pembina Institute, said the study raises a number of issues.
“Decision-makers need to (consider) this information in determining if it is appropriate to approve new projects,” he said. “Regulatory submissions already show that planned production will exceed legal limits for pollutants which means approvals must be slowed or better technologies implemented.”