A re-analysis and review of elemental and polycyclic aromatic compound deposition in snow and lake sediments from Canada's Oil Sands Region integrating industrial performance and climatic variables

Incorporating Industrial and Climatic Covariates into Analyses of Fish Health Indicators Measured in a Stream in Canada’s Oil Sands Region

“…While there could be effects of local stressors on fish in the Ells, such as road traffic related to production at HM, all of the industrial facilities identified in the best-fit ENs are physically outside the Ells basin. The potential influence of extrabasin facilities on both sites in the Ells watershed, coupled with no effects of land disturbance, suggests that the primary exposure mechanism is via atmospheric emissions and subsequent deposition of CoCs [20,32,[34][35][36][37][38]47,[78][79][80]. These results reinforce findings elsewhere, e.g., [32], including additional analyses suggesting the potential influence of the MRM on benthic invertebrates in the Ells basin [39] and data suggest CoCs are depositing throughout the watershed [37,41,[81][82][83].…”

“…Although some of the observed changes in environmental indicators in these areas may be associated with facilities, other phenomena may also affect the efficacy of spatial comparisons in the OSR. Contaminants of concern (CoCs) are emitted to the atmosphere from stacks and fugitive sources and many are deposited to the landscape [20,[32][33][34][35][36]. While the most intense deposition of materials often occurs within 10-20 km of the sources, e.g., [35], the deposition varies annually [20,32,37,38] and may also occur in areas used as references for studies in streams [39][40][41].…”

“…Contaminants of concern (CoCs) are emitted to the atmosphere from stacks and fugitive sources and many are deposited to the landscape [20,[32][33][34][35][36]. While the most intense deposition of materials often occurs within 10-20 km of the sources, e.g., [35], the deposition varies annually [20,32,37,38] and may also occur in areas used as references for studies in streams [39][40][41]. Additionally, in situ oil sand facilities may also be present upstream of reference sites [16,18], further altering the sensitivity of spatial designs to industrial influences.…”

“…Whereas some measurement types, such as chemical indicators in lake sediments and peat cores [47,52], may be less sensitive to these challenges, studies in streams require deliberate solutions. To overcome these challenges in flowing waters, generic covariates available from meteorological and hydrological stations can be incorporated to remove their influence on environmental indicators [32,39,53]. Although any residual variation could be qualitatively associated with extraneous sources, descriptors of industrial performance for individual facilities can also be included to identify any potential associations between the indicators and the local development.…”

“…Although any residual variation could be qualitatively associated with extraneous sources, descriptors of industrial performance for individual facilities can also be included to identify any potential associations between the indicators and the local development. Although not definitive, this approach may improve the utility of monitoring in the OSR, including identifying industrial influence without a pre-industrial baseline [20,32,39,[54][55][56] The purpose of this work is to evaluate the status of fish (lake chub; Couesius plumbeus) residing in the Ells River relative to industrial activity. To examine the potential effects of industrial influence, several approaches were used and were compared.…”