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Wood Buffalo AB
Canada

Developing temporal hydroecological perspectives to inform stewardship of a northern floodplain landscape subject to multiple stressors: Paleolimnological investigations of the Peace–Athabasca Delta


Year: 2012

Abstract:
Effective stewardship of ecologically-significant floodplain landscapes requires knowledge of the relative roles of natural processes and upstream human activities on environmental flows. In these landscapes, hydroecological conditions that develop from potentially competing drivers, such as climate change and industrial development, tend to be expressed at spatial and temporal scales that are often inadequately captured by existing monitoring datasets. Consequently, perceived cause–effect relations may be misunderstood, conflict can escalate among stakeholders, and effectiveness of surveillance systems, policies, and governance may be impaired. This is the context for the Peace–Athabasca Delta (PAD), an internationally-recognized water-rich floodplain landscape located in northern Alberta (Canada) that has been subject to multiple stressors. Here we synthesize evidence from paleolimnological records that have fostered an unparalled window into the natural history of this landscape. Over the past 12 years, we have assembled numerous decadal- to multicentennial-long records of hydrological and ecological variability, including an exceptionally detailed chronicle of Peace River flood frequency and magnitude spanning ~600 years. These efforts recently culminated in a 5200-year reconstruction of Lake Athabasca water-level history. Results have provided the foundation to identify drivers of landscape change and generate insight into the delta’s dynamic and ongoing evolution. Contrary to widespread perceptions that hydroelectric regulation of the Peace River since the late 1960s has reduced the frequency of ice-jam floods and lowered floodplain lake-water levels, results indicate that climate variability exerts the overwhelming influence on the delivery of water to the PAD. We show that impending climate-driven freshwater scarcity of a scale unprecedented in our collective societal memory now poses a significant threat to the ecological integrity of this world-renowned landscape and a major challenge to water resource managers. Also, we propose a hydroecological monitoring program, built upon the knowledge gained from our extensive process studies and paleoenvironmental research, to inform effective ongoing stewardship of the delta.

Has Alberta oil sands development altered delivery of polycyclic aromatic compounds to the Peace-Athabasca Delta?


Year: 2012

Abstract:
BACKGROUND: The extent to which Alberta oil sands mining and upgrading operations have enhanced delivery of bitumen-derived contaminants via the Athabasca River and atmosphere to the Peace-Athabasca Delta (200 km to the north) is a pivotal question that has generated national and international concern. Accounts of rare health disorders in residents of Fort Chipewyan and deformed fish in downstream ecosystems provided impetus for several recent expert-panel assessments regarding the societal and environmental consequences of this multi-billion-dollar industry. Deciphering relative contributions of natural versus industrial processes on downstream supply of polycyclic aromatic compounds (PACs) has been identified as a critical knowledge gap. But, this remains a formidable scientific challenge because loading from natural processes remains unknown. And, industrial activity occurs in the same locations as the natural bitumen deposits, which potentially confounds contemporary upstream-downstream comparisons of contaminant levels. METHODS/PRINCIPAL FINDINGS: Based on analyses of lake sediment cores, we provide evidence that the Athabasca Delta has been a natural repository of PACs carried by the Athabasca River for at least the past two centuries. We detect no measureable increase in the concentration and proportion of river-transported bitumen-associated indicator PACs in sediments deposited in a flood-prone lake since onset of oil sands development. Results also reveal no evidence that industrial activity has contributed measurably to sedimentary concentration of PACs supplied by atmospheric transport. CONCLUSIONS/SIGNIFICANCE: Findings suggest that natural erosion of exposed bitumen in banks of the Athabasca River and its tributaries is a major process delivering PACs to the Athabasca Delta, and the spring freshet is a key period for contaminant mobilization and transport. This baseline environmental information is essential for informed management of natural resources and human-health concerns by provincial and federal regulatory agencies and industry, and for designing effective long-term monitoring programs for the lower Athabasca River watershed.

Has Alberta oil sands development altered delivery of polycyclic aromatic compounds to the Peace-Athabasca Delta?


Year: 2012

Abstract:
BACKGROUND: The extent to which Alberta oil sands mining and upgrading operations have enhanced delivery of bitumen-derived contaminants via the Athabasca River and atmosphere to the Peace-Athabasca Delta (200 km to the north) is a pivotal question that has generated national and international concern. Accounts of rare health disorders in residents of Fort Chipewyan and deformed fish in downstream ecosystems provided impetus for several recent expert-panel assessments regarding the societal and environmental consequences of this multi-billion-dollar industry. Deciphering relative contributions of natural versus industrial processes on downstream supply of polycyclic aromatic compounds (PACs) has been identified as a critical knowledge gap. But, this remains a formidable scientific challenge because loading from natural processes remains unknown. And, industrial activity occurs in the same locations as the natural bitumen deposits, which potentially confounds contemporary upstream-downstream comparisons of contaminant levels. METHODS/PRINCIPAL FINDINGS: Based on analyses of lake sediment cores, we provide evidence that the Athabasca Delta has been a natural repository of PACs carried by the Athabasca River for at least the past two centuries. We detect no measureable increase in the concentration and proportion of river-transported bitumen-associated indicator PACs in sediments deposited in a flood-prone lake since onset of oil sands development. Results also reveal no evidence that industrial activity has contributed measurably to sedimentary concentration of PACs supplied by atmospheric transport. CONCLUSIONS/SIGNIFICANCE: Findings suggest that natural erosion of exposed bitumen in banks of the Athabasca River and its tributaries is a major process delivering PACs to the Athabasca Delta, and the spring freshet is a key period for contaminant mobilization and transport. This baseline environmental information is essential for informed management of natural resources and human-health concerns by provincial and federal regulatory agencies and industry, and for designing effective long-term monitoring programs for the lower Athabasca River watershed.

Has Alberta oil sands development increased far-field delivery of airborne contaminants to the Peace-Athabasca Delta?


Year: 2012

Abstract:
Identifying potential regional contamination by Alberta oil sands industrial emissions on sensitive ecosystems like the Peace–Athabasca Delta, ~ 200 km to the north, requires knowledge of historical contaminant levels and trends. Here we provide some of these critically-needed data, based on analysis of metals in a sediment core from an upland precipitation-fed lake in the delta. The lake is well-situated to record the anthropogenic history of airborne contaminant deposition for this region. Sediment records of metals of concern (Pb, Sb, As, Hg) reflect early to mid-20th century increases in North American industrial emissions, followed by reduced emissions due to improved industrial practices after 1950–70. Notably, Pb, Sb, As and Hg have declined since the onset of Alberta oil sands production, belying concerns that this activity has enhanced far-field atmospheric delivery of these contaminants to the delta.

Hydroecological responses of the Athabasca Delta, Canada, to changes in river flow and climate during the 20th century


Year: 2008

Abstract:
We employ water-isotope tracers and multi-proxy paleolimnological records to characterize contemporary controls on water balances of floodplain lakes in the Athabasca Delta, Canada, within the context of its hydroecological evolution over the 20th century. The insight gained from these approaches is necessary to gauge the hydroecological resiliency of the Athabasca Delta to past and future changes in Athabasca River flow regime. Results obtained from three lakes located in different regions of the Athabasca Delta indicate that hydroecological conditions were strongly affected by an engineered meander cut-off on the Athabasca River in 1972, intended to maintain flow in the river main stem, and a natural bifurcation of one of the major distributaries (Embarras River) in 1982, in response to progressive overextension of the delta to the east. Climate warming and naturally declining river discharge have also contributed to directional change. Recent drying trends reconstructed from sediment cores at two of the three lakes are likely representative of rapidly evolving hydroecological conditions in the south-eastern sector, based on mapping of a recent high-magnitude ice-jam flood that failed to recharge this portion of the delta, while wetting in the region of the third lake due to increased frequency of river flooding reflects increasing diversion of Athabasca River flow northward. Our findings highlight the hydroecological sensitivity of the Athabasca Delta to changes in the magnitude and timing of discharge in the Athabasca River and heighten the need for informed management strategies to safeguard the integrity of this unique wetland ecosystem. Copyright © 2008 John Wiley & Sons, Ltd.

Oil sands pollutants in traditional foods


Author(s): Edwards, J.

Year: 2014

Abstract:
People who worked in the oil sands, as well as "people who consumed traditional foods more frequently and those who consumed locally caught foods were more likely to have cancer," said [McLachlan] in an interview. "Industry is expediting that transition [to store-bought foods] in Fort Chipewyan because people are con- cerned about the quality of the tradi- tional foods in a way that they wouldn't be in other parts of northern Canada," said McLachlan. The products available in local stores are "convenience foods," said McLachlan. "The healthy foods that we like to promote in big cities like fresh fruits and vegetables just aren't available."

Citation:
Edwards, J. (2014).  Oil sands pollutants in traditional foods. Canadian Medical Association Journal. 186(12), 1 page. Abstract