Assessment of metals in bed and suspended sediments in tributaries of the Lower Athabasca River.

Several oil sands mines and refineries are currently recovering oil from the Athabasca River region near Fort McMurray, Alberta. Planning and construction of additional oil sands mines are in various stages of completion. Due to environmental concerns for aquatic life in areas downstream from current and future oil sands activities, surveys were conducted between 1998 and 2000 to determine whether the quality of water and sediments in tributaries of the Athabasca River are affected by flowing through reaches with exposure to natural oil sand deposits. This paper presents the results for metals in bed and suspended sediments collected from the Mackay, Steepbank, and Ells rivers during those surveys. The suspended sediments had a clay content (n = 7) ranging from 36.2% to 65.0%, while bed sediments, which consisted of a predominant sand fraction, had percent clay (n = 39) ranging from 0.0% to 38.1%. A Mann-Kendall non-parametric analysis to assess the longitudinal trend of the metals in the bed sediments found no significant (alpha = 0.05) downstream trend in the Mackay or Steepbank rivers; however, the Ells River displayed a generally decreasing tend from upstream to downstream. The results provide no indication that metal concentrations in the bed sediments and/or suspended sediments of the Mackay, Steepbank, and Ells rivers increase significantly as the three tributaries flow through reaches that have natural oil sand exposures (McMurray Formation).

The characterization and distribution of inorganic chemicals in tributary waters of the lower Athabasca river, Oilsands region, Canada.

At present, there are two large industrial plants recovering oil from the lower Athabasca oil sands area and there are plans for several more mines in the area. There are environmental concerns for aquatic life in areas downstream of current and future oil sands activities. To assess and predict potential impacts of industrial activities, it is important to separate impacts from those produced by naturally occurring oil sands deposit. Studies were therefore conducted to determine whether the water quality of tributaries to the Athabasca River, which have not been impacted by anthropogenic activities, is affected by inorganic constituents resulting from flowing through reaches with natural oilsands deposit. Three tributaries, Steepbank River, Mackay River, and Ells River at upstream and downstream locations on each stream were investigated during four surveys from 1998 to 2000. In addition to some physical parameters such as pH, conductance and hardness and the major ions (calcium, magnesium, sodium, potassium, bicarbonate, chloride, sulfate, and silicates), seventeen trace metals were investigated. Some of these metals, especially iron and manganese, were of high concentrations and in some instances, particularly in a survey conducted during the spring freshets in April 1999, exceeded guidelines for the protection of aquatic life. The observed concentrations of metals seem to be of natural origin and can be used as base-line data for future assessment of anthropogenic activities in the oil sand region.

Monitoring the hydrology of Canadian prairie wetlands to detect the effects of climate change and land use changes.

There are millions of small isolated wetlands in the semi-arid Canadian prairies. These sloughs' are refuges for wildlife in an area that is otherwise intensively used for agriculture. They are particularly important as waterfowl habitat, with more than half of all North American ducks nesting in prairie sloughs. The water levels and ecology of the wetlands are sensitive to atmospheric change and to changes of agricultural practices in the surrounding fields. Monitoring of the hydrological conditions of the wetlands across the region is vital for detecting long-term trends and for studying the processes that control the water balance of the wetlands. Such monitoring therefore requires extensive regional-scale data complemented by intensive measurements at a few locations. At present, wetlands are being enumerated across the region once each year and year-round monitoring is being carried out at a few locations. The regional-scale data can be statistically related to regional climate data, but such analyses cast little light on the hydrological processes and have limited predictive value when climate and land use are changing. The intensive monitoring network has provided important insights but it now needs to be expanded and revised to meet new questions concerning the effects of climate change and land use.

Hospital ownership, performance, and outcomes: assessing the state-of-the-science.

OBJECTIVE: This study 1) identified the research evidence; 2) assessed the state-of-the-science surrounding hospital ownership, performance, and outcomes in acute care hospitals in the United States; and 3) identified measurable components of hospital performance and outcomes for the organization, patient, and community. BACKGROUND: As the size of the nonprofit sector decreases and the size of the for-profit sector increases, hospital ownership warrants examination. Most research has focused on either ownership and performance or ownership and outcomes, rather than the potential interaction of all three variables. METHODS: A comprehensive, computerized search of the healthcare research literature yielded 69 data-based references published between 1985 and 1999. Coding sheets were developed to abstract the articles. Analysis involved synthesizing the research evidence for each of the three major variables and their components. RESULTS: Hospital ownership has an impact on hospital performance in relation to system operations; costs, prices, and financial management practices; and personnel issues. Organizational outcomes are similar among hospital ownership types in relation to increasing administrative costs and overall mediocre efficiency. Organizational outcomes differ among hospital ownership types in relation to nursing staff mix and professional satisfaction. The association of hospital ownership with patient outcomes varies depending on the dimension measured. The evidence is mixed or inconclusive regarding hospital ownership and access to care, morbidity, and mortality. The association of hospital ownership and adverse events is consistently supported. Hospital ownership status has an impact on the type and magnitude of community benefits. Differences among the three hospital ownership types are minimized in a competitive market. CONCLUSIONS: This study reinforces the position that nurse researchers need to include hospital ownership as an important structural variable in their studies of hospital-based nursing. Examining the conceptual links between ownership, performance, and outcomes requires the integration of macro-level and micro-level theory.