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Abbotsford BC
Canada

Accumulation of fish mixed function oxygenase inducers by semipermeable membrane devices in river water and effluents, Athabasca River, August and September 1994


Year: 1996

Abstract:
Semipermeable Membrane Devices (SPMDs) were deployed for 2 weeks in waters ofthe Athabasca and Lesser Slave Rivers and in four pulp mill effluents and wastewater from one oil sands mining and upgrading facility. Success of recovery of the SPMDs was 66 %, with loss caused by high water velocity and shifting channels and sediments. SPMD extracts accumulated chemicals that induced mixed function oxygenase (MFO) in a fish cell line. For expressing the potency of SPMD extracts as inducers in fish cells, MFO induction in cells exposed to SPMD extracts was compared to MFO induction in cells exposed to 2,3,7,8-tetrachlorodibenzo-p- dioxin (TCDD). This does not imply that the SPMD extracts contained TCDD or any other dioxin or furan, only that the extracts contained chemicals that were equivalent in MFO-inducing potency to a certain amount of TCDD. MFO induction was expressed as "EROD potency equivalents in pg/g". Extracts of SPMDs from pulp mills were two to five times as potent as extracts of SPMDs exposed to background river water. SPMD extracts from three of the four pulp mill effluents tested (Weldwood, Alberta Newsprint and Slave Lake Pulp) had 62.0, 53.5, and 29.7 pg EROD potency-EQ/g, respectively, significantly more than in Athabasca River water (12.6 pg EROD potency-EQ/g = "background"). SPMDs exposed to effluent from Millar Western (23.0 pg EROD potency-EQ/g) had potencies within the 95 % confidence interval o f background. The levels of MFO induction in SPMDs exposed to river water increased downstream of Fort McMurray. In this area, SPMDs accumulated inducers from the river at levels ranging from 58.5 to 728 pg EROD potency-EQ/g. SPMD accumulation was highly variable, which indicated an unknown source of inducers, possibly an effluent from the town or input from natural erosion of the oil sands. SPMDs deployed in effluent from Suncor accumulated the most MFO-inducing chemicals (16,800 pg EROD potency-EQ/g), with induction potency over 20 x that of SPMDs from river water upstream of Suncor. Although this study was preliminary, the results indicated that SPMDs from the four pulp mill effluents contained small quantities of MFO inducers. Compared to MFO induction by extracts of SPMDs deployed in two Ontario bleached kraft mill effluents, the pulp mill effluents from the Athabasca River were one third to one twentieth as potent. By contrast, very high quantities of MFO inducers were accumulated from Suncor effluents. SPMDs deployed in Athabasca River waters downstream of Fort McMurray also contained inducers, indicating some unknown anthropogenic or natural source in this area.

Association of postfire peat accumulation and microtopography in boreal bogs


Year: 2005

Abstract:
Peatlands accumulate organic matter as peat because of disproportionate rates of production and decomposition. However, peat accumulation heterogeneity has not been well studied along the microtopographic gradient (hummocks vs. hollows), particularly with respect to fire. Fire affects peatland species composition by differentially removing vegetation and resetting succession, resulting in peat accumulation changes. We examined peat accumulation and microtopography in two historically burned bogs in Alberta, Canada. Measurements of current and historic microtopography were made, and cores were collected along the gradient to identify depth of peat accumulated since fire, as well as to assess properties of the accumulated peat. Current microtopography is significant and correlated with the immediate postfire surface relief. However, differences in the magnitude of variability between sites suggests that differential rates of growth between features are exacerbated between sites and reflected in bog microtopography. Rates of organic matter accumulation, ranging from 156 to 257 g.m^sup -2^.year^sup -1^, were elevated but comparable to published rates of recent accumulation. Organic matter content and accumulation rate were greater for hummocks than hollows at Athabasca bog, but the difference between features diminished at Sinkhole Lake, suggesting that the pattern and properties of peat accumulation and microtopography postfire may be attributable to differences in site conditions.

Concentrations of metallothionein in fish Peace Athabasca and Slave River basins September to December 1994


Year: 1996

Abstract:
Fish from Peace, Athabasca and Slave rivers and their tributaries are exposed to a variety of pulp mill, municipal and industrial effluents (EnviResource 1995; Brown and Vandenbyllaardt, 1996). Assessments of effects of contaminants have focussed on chlorinated organic compounds, such as dioxins and furans (Pastershank and Muir, 1995), and on alterations of parameters affecting reproduction physiology in individual fish (Brown et al., 1993; Brown et al., 1996; Lockhart et al., 1996). These studies have demonstrated that there is exposure to organic contaminants because mixed function oxidase activities are elevated (Lockhart, et al., 1996; Lockhart and Metner, 1996); and that fish collected downstream from the pulp mills may be stressed, because they exhibit a high percentage of sexually immature individuals, and they have depressed circulating concentrations of gonadal steroid hormones (Brown et al., 1993; Brown et al., 1996). The purpose of the research described in this report was to initiate studies to see if metals may be contibuting to these stresses. The objective was to evaluate whether the metal-binding protein, metallothionein, was elevated in organs of burbot, longnose sucker, northern pike or flathead chub collected downstream from pulp mills and other effluent discharge points, and whether there was evidence of cumulative impacts with progression downstream in these rivers. An increase in MT concentrations in fish represents a molecular response that generally indicates exposure and development of resistance to toxicity to metals, especially Cd, Cu, Hg and Zn (Klaverkamp et al. 1991; Roesijadi, 1992). The study was designed by the Northern River Basins Study Science Directors and the Contaminants Component Leader, and was based on selecting fish collection sites on their proximity to discharges from pulp mills. Additional information on fish collection sites and on general biological parameters of fish collected in 1994 is presented in other reports (EnviResource 1995; Brown et al. 1996). Two observations were made, both in burbot, which may indicate exposure to elevated metal concentrations and the presence of cumulative impacts. First, the greatest difference in MT concentrations between collection sites was observed in kidney of burbot collected in the Slave River Delta (SRD) of Great Slave lake. MT concentrations in kidneys from these fish ranged from approximately 7-times to 26-times higher than those concentrations found in kidneys of burbot from other collection sites. MT concentrations in gill of burbot from SRD were also the highest observed. The SRD burbot may be exposed to metals due to natural conditions of high mineralization in the Great Slave Lake Delta or other parts of the lake; or these fish may be exposed to metals discharged by mining operations, such as the decommissioned lead-zinc mine at Pine Point. The counterclockwise current in this portion of the lake could transport metals from a western source, such as Pine Point, to the Slave Delta (English, 1984). Second, a progressive increase in MT concentration in proceeding from upstream fish collection sites to downstream sites was observed in concentrations of MT in burbot liver. In the Peace River and associated tributaries (Little Smoky, Smoky, and Wapiti), there is a progressive increase of up to 3.34-fold in burbot liver [MT] moving from upstream to downstream collection sites. In the upper Athabasca River system, there is a progressive increase of up to 2.33-fold in burbot liver [MT] moving from upstream to downstream collection sites.

Depositional history of sediment in Great Slave Lake: spatial and temporal patterns in geochronology, bulk parameters, PAHs and chlorinated contaminants


Year: 1996

Abstract:
This report presents the results of August 1993 and March 1994 sediment studies in the West Basin of Great Slave Lake. In August 1993, a series of 10 surficial sediment samples were collected in the vicinity of the Slave River mouth. PCB was the predominant organochlorine (OC) compound detected followed by chlorobenzene, total DDT, HCH, and dieldrin. Concentrations were low and comparable to values reported for other subarctic and arctic lakes. There was no apparent pattern in the distribution of these compounds relative to the Slave River outflow. PAHs were very abundant and were dominated by benzo(g,h,i)perylene, benzo(e)pyrene, and phenathrene: concentrations were slightly higher offshore the river mouth than elsewhere. PCDD and PCDF concentrations were exceedingly low. PCDDs were dominated by DiCDD and OCDD while PCDFs were dominated by DiCDF and TriCDF. The presence of the lower chlorinated forms may be suggestive of a pulp and paper mill influence. Similarly the presence of pentachloroanisole, trichloroveratrole, and tetrachloroveratrole may be suggestive of a pulp and paper mill influence. Two cores were collected in August 1993 on the shelf region immediately west of the Slave River. Station depths were less than 30 m. Both cores were in areas of high erosion and could not be assigned meaningful dates. In March 1994, a series of sediment cores was collected at five sites (Sites 12, 13, 16, 19, and 23) in the West Basin, to the west of the August 1993 surficial sediment and coring studies. A single core from each site was dated at the Freshwater Institute and two additional cores (one each from Sites 13 and 19) were dated at the National Water Research Institute. Cores from four of the sites were in depositional areas while the core collected offshore of the Slave River mouth (Site 23) was in an erosional area. However, sufficient sediment deposition had occurred at this site for the core to be dated. The two cores examined from Site 13, in the central region of the West Basin, gave similar dating estimates. However, the two cores examined from Site 19, further to the east, gave somewhat different estimates from each other. These two cores were collected in a less physically-stable region of the lake with some evidence of postdepositional erosion of older material on top of newer sediments. The core from Site 23 was in the least stable region o f the five sites examined. Sedimentation rate estimates were similar to those for Lake Athabasca and Lakes Ontario and Erie. They were higher than estimates for subarctic and arctic lakes and for Lake Superior. Based on estimates of the suspended sediment loading to Great Slave Lake, we conclude that our cores were not collected in the high-sedimentation regions of Great Slave Lake. The greatest sedimentation may occur offshore of the Slave River mouth. Analysis of cores collected in March 1995 should allow us to confirm this hypothesis. Two cores (Cores 12B and 19B) were analyzed for organochlorine compounds. Concentrations of OCs in Core 12B, collected offshore of Hay River, were relatively high and require verification. Thus, these data are not presented in this report. For Core 19B, there was some evidence of increasing PCB, chlorobenzene, and HCH concentrations over the 1949 - 1994 period investigated. Dieldrin showed a weaker time trend. Based on the analysis of sediment trap material collected in August 1994, we conclude that the Slave River is a significant source of organochlorine compounds to Great Slave Lake. Cores from Sites 12 and 19 were analyzed for PAHs. Although the same number of slices were examined for both cores, slices from Core 12B did not extend as far back in time: thus, the PAH record has not been determined for Core 12B prior to the mid 1960s. Both cores were dominated by naphthalene, 1-methylnaphthalene, and 2-methylnaphthalene suggesting a petrogenic source. Concentrations were higher at Site 19, closer to the Slave River, than Site 12. There was strong evidence that concentrations of these compounds increased since the 1960s suggesting an additional anthropogenic source of these PAHs: temporal patterns of increase differed for Core 12B and Core 19B. Fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benzo(a)anthracene, and chrysene all occurred in higher concentrations in Core 12B than Core 19B. Concentrations varied little over time for Core 19B but showed some evidence of higher concentrations in Core 12B for two periods - the late 1970s and the late 1980s. This is suggestive of a localized input, possibly from Hay River. Higher molecular weight PAHs occurred in similar concentrations in Cores 12B and 19B. There was a suggestion of slightly higher concentrations of these compounds in Core 12B during the late 1970s than earlier and later times. PCCDs and PCDFs concentrations were determined in Cores 19D and 23A. Concentrations of PCDDs were substantially higher during the 1950s through the 1970s than in more recent times. Temporal patterns of increase differed for Core 19D and Core 23A. PCDDs were dominated by HpCDDs and OCDDs with only low concentrations of the lower chlorinated forms being detected. Total PCDFs were less abundant than PCDDs: this is in notable contrast to the surficial samples where PCDDs and PCDFs occurred in similar concentrations to one another. PCDFs (primarily TriCDF and TCDF) showed some evidence of increasing concentrations since the 1950s for Core 23A while this trend was less apparent for Core 19D. These increases in PCDD and PCDF concentrations may be related to increased atmospheric sources and/or paper and pulp mill activities. There was some evidence of a pulp and paper mill signature in Core 19B with pentachloroanisole increasing in concentration from 1949 to the early 1980s and then declining somewhat thereafter: trichloroveratrole and tetrachloroveratrole occurred in low concentrations in the 1950s and in increasing concentrations thereafter. Total organic carbon (TOC) and total organic nitrogen (TON) concentrations were determined in Cores 13C and 19D. Concentrations of both compounds have increased since the early 1900s with the greatest increase occurring since the 1950s. Moreover, the increase was more pronounced in Core 13C than Core 19D. This suggests that the West Basin of Great Slave Lake has undergone a slight increase in productivity, possibly due to land clearing and increased anthropogenic development in the Peace and Athabasca River watersheds. Localized activities, occurring at the towns of Hay River and Yellowknife, may also have been important. While Great Slave Lake is essentially a pristine system, it does show signs of recent anthropogenic contamination. A significant fraction of OCs, PAHs, PCCDs, and PCDFs probably entered the West Basin of Great Slave Lake with Slave River inflow. However, the primaiy source of these compounds is less certain, e.g., localized inputs from industries along the Peace and Athabasca Rivers and/or atmospheric deposition (wet and dry) over the broader watershed with the eventual transport of these compounds into the Peace, Athabasca, and Slave rivers and then into Great Slave Lake.

Ecophysiological adaptations of black spruce (Picea mariana) and tamarack (Larix laricina) seedlings to flooding and nutrition stress


Author(s): Islam, M. A.

Year: 2004

Abstract:
Black spruce (Picea mariana (Mill) B. S. P.), an evergreen conifer and tamarack (Larix laricina (Du Roi) K. Koch), a deciduous conifer, are the predominant tree species of boreal peatlands of northern Alberta, Canada. The harsh boreal environment is characterized by low nutrient availability, low soil temperature and high water tables. The rise of the water table creates anaerobic conditions in the root zone where the ammonium form of nitrogen becomes more available while the availability of nitrate decreases. Microsite variation within and between years also results in variable nutrient availability to plants. In order to understand the mechanisms of flooding tolerance, nutrient uptake pattern, and growth responses, seedlings of both species were subjected to flooding and different forms and levels of nitrogen fertilizers in a series of growth chamber experiments. Results of this project suggest that tamarack is more flood tolerant than black spruce since it maintained a higher gas exchange rate and root hydraulic conductance apparently because of its higher root respiration and greater allocation of carbohydrates to the root. Gas exchange of tamarack was also unaffected by the application of exogenous ethylene though root hydraulic conductivity increased. Additionally, tamarack was able to acclimate morphologically to flooding by producing stem hypertrophy and adventitious roots while black spruce lacked such adaptations. While nitrate and ammonium uptake was inhibited in flooded seedlings of both species, non-flooded black spruce showed a clear preferential ammonium uptake and tamarack exhibited an equal uptake of both forms of nitrogen. Low supply of nitrogen affected gas exchange of black spruce more negatively than tamarack. On the other hand, higher nutrient availability for two consecutive seasons did not have a significant positive effect on growth in black spruce while it increased gas exchange rate and biomass production in tamarack dramatically. Maintenance of higher root respiration, root hydraulic conductance, and equal carbon allocation to roots allowed tamarack to withstand flooding while equal uptake of ammonium and nitrate, and higher growth rate in conditions of variable nutrient availability would confer a competitive advantage to tamarack to succeed in the boreal peatland environment.

Environmental contaminants in fish: Spatial and temporal trends of polychlorinated dibenzo-p-dioxins and dibenzofurans Peace Athabasca and Slave River basins 1992 to 1994


Year: 1997

Abstract:
As part of the work to examine the impact of development on ecosystem health and integrity on the Peace and Athabasca river basins in Alberta, the Northern River Basin Study (NRBS) was required to determine “the contents and nature of the contaminants entering the system ... particular reference to water, sediments and biota" and to determine “... the current concentration of contaminants in water and edible fish tissue and how are these levels changing through time and by location". The Reach Specific Study (RSS) was designed to measure spatial and temporal trends of contaminants including polychlorinated dibenzo-p-dioxins and -dibenzofurans (PCDD/Fs) in sediment, water and and biota (fish and invertebrate) samples collected at six locations on the upper Athabasca River downstream of Hinton (AB) in spring 1992, fall 1992 and spring 1993. The General Fish Collection (spring 1992), the Long nose sucker and Northern pike liver study (fall 1994) and the Special Burbot Collection (fall 1992 and 1994), and the Ft. Chipewyan winter fishery study (1994/95) were also conducted to examine levels in fish tissues within the Athabasca, Peace and Slave River basins. The purpose of this report is to summarize the levels of PCDDs and PCDFs in fish from these various studies and to assess temporal trends of 2,3,7,8-TCDD and 2,3,7,8-TCDF by comparison with previously published data. A second objective was to reexamine pathways of accumulation of 2,3,7,8-TCDD and 2,3,7,8-TCDF from water and suspended sediment to fish, first measured in the upper Athabasca River in 1992 (Pastershank and Muir 1995). The major PCDD/F congeners in muscle (skinless fillet) of mountain whitefish and northern pike samples collected in the upper Athabasca River downstream of Hinton in fall 1992 and spring 1993 were 2,3,7,8-TCDD and -TCDF. Mean concentrations of 2,3,7,8-TCDD in mountain whitefish ranged 0.6 to 7.7 pg-g'1wet wt and from 1.7 to 9.8 pg-g"1for 2,3,7,8-TCDF. Concentrations of other 2,3,7,8- substituted penta- to octachloro- PCDD/F congeners were generally much lower or non-detectable in both species. Two lower chlorinated congeners, 2,7/2,8-dichlorodibenzodioxin and 2,3,8- trichlorodibenzofuran were detected in most samples ofmountain whitefish from fall 1992 at low pg-g'1 concentrations. TCDF was the most frequently detected PCDD/F congener in longnose sucker and northern pike livers collected from the Wapiti/Smoky and Peace Rivers in fall 1994. TCDF concentrations in liver were in the low pg-g'1range similar to levels in muscle of these species. Highest concentrations of TCDF in livers of longnose sucker (9.2 ± 17.8 pg-g"1) were found at a site on the Smoky River (SRI) downstream of the pulp mill effluent near Grande Prairie. Temporal trends in 2,3,7,8-TCDD and -TCDF in mountain whitefish were examined over a four year period by combining the three sampling times in the upper Athabasca River with data from previous studies (DFO National Dioxin Program 1989). There was a definite decline in 2,3,7,8-TCDD and - TCDF concentrations in mountain whitefish downstream of the Hinton but most of the decrease took place in the period 1989 to 1992. The extent of the decline depends to a large extent on which results for spring 1993 are used. If samples from the near-field sites of Weldwood and Obed (mean concentrations of 1.1 and 2.6 pg-g"1wet, for TCDD and TCDF respectively) are used the decline is about five-fold for both TCDD and TCDF over four years. But if the fish from Emerson Lake (48 km downstream) are included (mean concentrations are 3.6 and 7.1 pg-g"1wet, for TCDD and TCDF, respectively) the decline is about 3-fold. In general, concentrations of PCDD/Fs were higher in burbot liver than in muscle or liver of mountain whitefish or northern pike and a greater number of congeners were detected. TCDF was detected i (mean concentrations, 0.30 to 65 pg-g'1) in 86% o f all 203 burbot liver samples analysed, while 2,3,7,8- TCDD was detected in 35% of samples (mean concentrations, <0.3 to 8.5 pg-g'1). Two other 2,3,7,8- substituted- PCDD/F congeners, 1,2,3,6,7,8-HxCDD and the heptachlorodioxin, 1,2,3,4,6,7,8-HpCDD were detected in 37% o f burbot liver samples. OCDD was also detected relatively frequently (17%) while OCDF was found in only 3 of 203 samples. Di and trichloro-CDDs and CDFs were detected infrequently in burbot liver and at low levels relative to tetra- to octachloro congeners. Significantly higher levels (ANCOVA; Tukey’s or least squares means test) of TCDD and TCDF were found in burbot liver downstream of the Hinton BKM than at all other sites. Levels of 2,3,7,8-TCDD and -TCDF in burbot liver were lower in the. fall 1994 collection than in fall 1992 at four sites; downstream of the Grande Prairie pulp mill outlet, PR2 on the Peace River near the mouth ofthe Notikewin River (674 km from confluence ofthe Peace/Slave), and PR3 upstream ofFort Vermillion (396 km). Comparison of concentrations in burbot liver near the BKM at Grande Prairie was problematic because sampling sites were not in the same locations each year. Nevertheless, the results show a decline of 4 to 17-times in the case of 2,3,7,8-TCDF at three sites. No significant decline of TCDD or TCDF concentrations was found in burbot livers from PR2. The burbot liver results, expressed as TCDD TEQ’s, also agreed well with those of Swansonet ak (1995) who found a 5-fold decline in TEQs downstream of the Grande Prairie BKM between summer 1991 and spring 1994. Concentrations of all 2,3,7,8-substituted PCDD/F congeners in composite samples of fish muscle from the Ft. Chipewyan domestic winter fishery in the Peace-Athabasca delta were at or near detection limits (<0.1 to <0.8 pg-g'1). Only 2,3,7,8-TCDF was detectable in most samples (<0.1 to 0.5 pg-g'1). Burbot liver samples from the three sites in the Peace-Athabasca delta had higher levels o f 2,3,7,8-TCDF than burbot muscle (1.7 to 2.9 pg-g'1). These levels were similar to those at other far-field and reference sites located far from BKMs. The bioavailability of TCDD and TCDF to mountain whitefish and northern pike was assessed using biota-sediment (or suspended sediment) accumulation factors (BSAF/BSSAFs). BSAFs for 2,3,7,8- TCDD ranged from 1.1 to 2.0 and for TCDF from 0.19 to 1.63 in mountain whitefish in spring 1992. A similar range of BSAFs was found in 1993. BSSAFs for both 2,3,7,8-TCDD and TCDF were generally lower and showed greater consistency than BSAFs with distance from the BKM. The results suggest that TCDD/TCDF levels in fish can be estimated with an average, site specific, BSAF or BSSAF using concentrations of TCDD/F in bed sediment or suspended sediments. Application of the Thomann and Connolly food chain model (steady-state version) to predict levels of TCDF in the food web downstream of Hinton showed that good agreement between predicted and observed results could be obtained for benthic feeding organisms (and longnose suckers and pike) which were close to equilibrium with sediments or biofilm. The model overpredicted concentrations in filter-feeding invertebrates and mountain whitefish; these organisms are not in equilibrium with TCDF in the water and suspended solids in the river due to the dynamic nature ofthe system. All mean concentrations of TCDD TEQs in fish muscle or liver were below the limit of 20 pg-g'1(wet wt) set by Health Canada for commercial sale and export of fish. A few individual samples, mainly burbot liver from the Athabasca River downstream of Hinton, exceeded the 20 pg-g'1guideline. Assuming TCDD TEQs of 8.3 pg-g'1in mountain whitefish downstream of Hinton a 60 kg individual would have to consume 72 g of mountain whitefish muscle per day to exceed the Health Canada

Environmental contaminants in mink - Peace and Athabasca Rivers, December, 1991 and January 1992


Author(s): Wayland, M.

Year: 1995

Abstract:
Analyses were done on mink that were collected from three sites: 15 km downstream from the Weyerhaeuser Canada pulp mill about 2 km from the Wapiti River on Bear and Olsen Creeks; on Galoot Lake on the Athabasca Delta and on creeks about 5 km from the Athabasca River and approximately 40 km downstream from Hinton

Mapping how we use our land: Using participatory action research


Year: 1994

Abstract:
The study area of the traditional land use and occupancy study profiled in this booklet is broadly speaking northeast Alberta, south of the Clearwater River, west of the Alberta/Saskatchewan border, north of the Cold Lake air weapons range and east of the Athabasca River. In this region Athapaskan, Cree, and Métis people have mixed with Euro-Canadians engaged in the fur trade since the arrival of Peter Pond in 1780. The area generally opened up to settlement with steamboats on the Athabasca, the Alberta and Great Waterways Railway and the impetus created by World War II to construct roads into the region. By the 1950s the industrial economy was becoming more and more established and Aboriginal participation in wage work began to increase. Through the 1960s and 1970s with the establishment of new tar sands plants with state of the art technology, Fort McMurray became a Canadian boom town, and there was less and less incentive for Aboriginal people to maintain a full-time presence in the bush economy. Trapping, hunting, fishing and gathering became part-time activities for most, and thousands of outsiders also began to hunt and fish in the Aboriginal homelands with the assistance of seismic access roads, four-wheel-drive vehicles and float planes. Life for regional residents continues to change at a fast pace as the Alberta-Pacific pulp mill comes on stream and tar sands projects are expanded. These factors provided the incentive for the Athabasca Native Development Corporation to undertake the traditional land use and occupancy study described in this booklet.

Nutrient enrichment in the Peace Athabasca and Slave River: Assessment of present conditions and future trends


Author(s): Chambers, P. A.

Year: 1996

Abstract:
The aim of this report was to address the Northern River Basins Study (NRBS) question: “Are the substances added to the rivers by natural and manmade discharges likely to cause deterioration of the water quality?” In this report, the word “substances” was taken to mean nutrients or, more specifically, nitrogen and phosphorus. Other NRBS reports have addressed the impact of effluent loading from the perspective of contaminants. This report synthesizes results from research and monitoring studies undertaken as part of the NRBS to characterize nutrient loading from all point and diffuse sources in the Northern River basins, evaluate the impacts of nutrient loading on river chemistry, assess the response of riverine biota to nutrient loading from pulp mill and municipal effluents in situ, quantify nutrient responses of benthic biota, and investigate interactions between nutrients and contaminants in pulp mill effluent on food webs. These findings are used to assess the state of aquatic ecosystem health, and develop scientific and management recommendations for the Northern River basins. During fall, winter and spring, elevated nitrogen and phosphorus concentrations were observed on the Athabasca River downstream of Jasper, Hinton, Whitecourt and Fort McMurray and on the Wapiti River downstream of Grande Prairie. In the Athabasca River, 20% of all TP samples and 2% of all TN samples exceeded the Alberta Surface Water Quality Objective of 0.05 mg/L TP as P and 1.0 mg/L TN as N. Most of these exceedances occurred during summer and were likely due to high particulate concentrations. In the Wapiti River, 74% of TP samples and 19% of TN samples collected near the mouth exceeded the Alberta Surface Water Quality Objectives compared with exceedances of only 12% for TP and 0% for TN upstream of Grande Prairie. This suggests that nutrients from the City of Grande Prairie and Weyerhaeuser of Canada Ltd. effluents contribute to non-compliance. Annually, continuously-discharging industrial and municipal sources contribute 4 to 10% of the TN load and 6 to 16% of the TP load in the Athabasca River, with the contribution being higher during winter. Likewise, continuously- discharging industrial and municipal sources contribute 20% of the TN and 22% of the TP load in the Wapiti River annually. For the Peace River mainstem there is no evidence of nutrient impacts and the same is likely, true for the Slave River, although there are only limited nutrient data for this river. Elevated nutrient concentrations in the Athabasca and Wapiti rivers have increased periphyton biomass and benthic invertebrate densities and, for the Athabasca River downstream of Hinton, increased the length and body weight of spoonhead sculpin (Cottus ricei), a small insectivorous fish species. Enrichment studies conducted with nutrient diffusing substrata in fall 1994 showed that periphyton growth was nutrient saturated for at least 2.5-4 km downstream of Jasper, from downstream of Hinton to upstream of Whitecourt, for at least 3 km and possibly up to 48 km downstream of Fort McMurray, and for at least 2 km downstream of the Grande Prairie bleached kraft pulp mill. Phosphorus concentrations at sites immediately upstream of the outfalls to these nutrient-saturated reaches were usually < 2 g/L SRP in the Athabasca River and 4-6 g/L SRP in the Wapiti River. These concentrations are similar to the 2-5 g/L SRP that was determined to be the concentration above which the growth of individual cells and thin periphyton films in artificial streams are phosphorus saturated. Periphyton growth was nitrogen limited from downstream of the Alberta Newsprint Co. to the confluence of Lesser Slave River and in the Smoky River. The increase in periphyton biomass and benthic invertebrate densities downstream of effluent outfalls and, in the case of the benthic invertebrates, no loss of species suggests that the response to effluents is one of nutrient enrichment not toxicity. Studies conducted in artificial streams further showed that periphyton biomass and growth of several mayflies, stoneflies and caddisflies increased in response to nutrient or 1% effluent addition, with no significant difference between the two treatments. These results further verify that the response to the current level of effluent loading is one of nutrient enrichment. There is no evidence of adverse effects to the ecosystem (e.g., no benthic invertebrate species loss, no problems with dissolved oxygen levels that are directly caused by nutrient addition). While detailed investigations of spawning grounds and early rearing habitat for fish in the Northern Rivers were not undertaken, it does appear not that dissolved oxygen problems caused by nutrient addition are adversely affecting fish populations at present. The concern with nutrient addition to the Athabasca and Wapiti rivers appears, at present, to be largely one of aesthetics as perceived by increased periphyton growth. Aesthetic criteria for the protection of water bodies are often site specific and developed in consensus with the users of the lake or river. In the absence of any detectable deleterious effects of nutrient loading on the Athabasca and Wapiti rivers, the users must determine whether the increase in periphyton growth downstream of outfalls is acceptable or unacceptable. Given our current state of knowledge, setting effluent permit limits for phosphorus to control periphyton biomass at a specific level is not possible since there is as yet no quantitative relationship between river phosphorus concentrations and periphyton biomass for a given site. For example, periphyton biomass 1 km downstream of Hinton was found to range from 25 to 242 mg chlo/m2 for October 1990, 1992, 1993 and 1994 despite relatively constant TP loads from Weldwood of Canada Ltd. and relatively constant river flows (111, 134, 97 and 118 m3/s for October 1990, 1992, 1993 and 1994, respectively). Yet despite the lack of site-specific quantitative relationships between periphyton biomass and phosphorus concentration, experiments and in situ observations undertaken by the NRBS and other agencies have clearly shown that phosphorus (and, in some locations, nitrogen) are controlling factors for periphyton abundance in the Athabasca, Wapiti and Smoky rivers. Based on findings from studies reviewed in this synthesis report, the following key recommendations are proposed: • regular monitoring and reporting of nutrients from sewage treatment plants. This should be a license requirement. In addition, provision is needed for ensuring compliance with sampling and analytical procedures for all licensed dischargers (industrial and municipal) and to ensure training of certified operators to measure (and record) flow rates and discharge volumes and for enforcement of reporting requirements. Standard reporting requirements for water quality parameters should be established and reporting proper data should be a license requirement.

Persistent organic contaminants in sediments and biota of Great Slave Lake, Canada: Slave River and long-range atmospheric source influences


Author(s): Evans, M. S., & Muir D. C. G.

Year: 2016

Abstract:
Over 1993–1996, we conducted a series of studies to investigate the distributions of legacy persistent organic pollutants (POPs) in the West Basin and East Arm of Great Slave Lake with a focus on sediments and fish species common in traditional diets; lesser attention was paid to polynuclear aromatic hydrocarbons (PAHs) and chemicals associated with pulp and paper mill activity. The Slave River, formed by the confluence of the Peace and Athabasca Rivers, profoundly affects the limnology of the West Basin by transporting large quantities of water and suspended sediments into the lake. Most POPs occurred in substantially higher concentrations in sediments offshore of the Slave River inflow than in the remote East Arm where long-range atmospheric transport was inferred to be the primary source. POP concentrations tended to be higher in East Arm than the West Basin fish possibly because the low productivity of the East Arm provides less opportunity for contaminant dilution through fish growth and the adsorption onto organic particulates in the water column. Overall, POP concentrations were relatively low in plankton, lake trout fillet and burbot liver from both regions of the lake and generally comparable to other lakes located at similar latitudes. Since 1998, we have been monitoring POPs, mercury and other contaminants in lake trout and burbot under the Northern Contaminants Program in which we are contributing to national and international reporting and to the global understanding of contaminants and climate change on northern and other environments.

Relict grassland in northern Saskatchewan: A phytogeographic study in the Clearwater River Valley


Author(s): Johnson, R. H.

Year: 1989

Abstract:
The main purpose of this research was to characterize the vegetation of the open slopes along the lower Saskatchewan reach of the Clearwater River. Examination of the species that constitute a representative site and the environmental conditions within which they exist was essential to the prediction of vegetation status and continued site occupation. An hypothesis was put forward on the origin of these communities and various methods to measure environmental parameters were used to determine the present site conditions. Many plants of the community were found to be displaced in Saskatchewan flora range and outside their normal climatic region. Most notable species are Anemone cylindrica A. Gray, Artemisia frigida Willd., Aster conspicuus Lindl., A. laevis L., Penstemon gracilis Nutt. and Stipa curtiseta (Hitchc.) Barkworth. Near the steppe study site, Abiesbalsamea (L.) Mill. exists as an isolated population in well protected spring-sapping zones. Calamagrostis purpurascens R. Br., a northern resident found previously as far south as the Cluff Lake area, represents a southern range extension. The data collected suggest recent advancement of footslope overstory but that maximum upslope movement may have been reached. The grassland species present are explained as being a relict community of previously widespread steppe origin.

Suitability of small fish species for monitoring the effects of pulp mill effluent on fish populations, Athabasca River, 1994 and 1995


Year: 1996

Abstract:
The objectives of this project were addressed by first identifying common sentinel species immediately upstream and downstream of pulp mill effluents at Hinton and Whitecourt. Spoonhead sculpin and lake chub were identified as sentinel species because of their abundance in the Hinton and Whitecourt reaches of the river, respectively. These species are assumed to have limited mobility and a small home range. This project attempted to document the geographic extent of biochemical responses in fish subjected to prolonged exposures during low flow periods (i.e., fall and early spring). This was accomplished by conducting laboratory analyses on the fish tissues collected from the field to determine the potential for the pulp mill effluents to disrupt sex steroid levels and induce liver MFO activity.

The geochemical distribution of radium-226 in Cluff Lake uranium mill tailings


Author(s): Goulden, W. D.

Year: 1997

Abstract:
The choice of an input 'source term' for radium concentration into numerical transport models has been a challenge when attempting to predict long term impacts of uranium mill tailings storage. Physical and chemical separation methods were used to establish the geochemical distribution of radium in a fresh Cluff Lake uranium mill tailings sample. Analysis of the experimental data suggested that radium in Cluff Lake uranium mill tailings is present as a barium radium sulfate [(Ba,Ra)S0₄] coprecipitate. Even though radium is known to be strongly adsorptive, only a minor amount of radium absorption was calculated in the presence of competing cations in the Cluff Lake tailings pore fluids. While approximately 80% of the total radium present in the tailings was associated with the < 75μm size fraction (dominated by gypsum, illite, chlorite and iron hydroxide), the data suggests that the common trace mineral barite present in this fraction controls the radium pore fluid concentration. Of the total radium mass present in the tailings, 0.35% was released during deionized water leaching, which removed all of the readily water soluble fraction (11% of the solids mass). Coprecipitation theory using barite as a host mineral for radium adequately predicts equilibrium radium pore fluid concentration. The calculated equilibrium value agrees well with in situ empirical data for Cluff Lake pore fluids, column lysimeter leachates and the empirical experimental data from this study. The results of this study have several environmental implications for stability and transport of ²²⁶Ra associated with sulfuric acid leached and lime neutralized uranium mill tailings. If the barium and radium solids concentrations are known, the equilibrium radium pore fluid concentration can be predicted using coprecipitation theory. The majority of the radium mass (>99%) will be highly stable in the solid phase when in contact with deionized water (or by extrapolation, very low ionic strength waters). The radium concentration in solution is sensitive to sample disturbance; therefore, sampling should be performed with care not to agitate the tailings solids during liquid recovery.

Water quality overview of Athabasca River Basin


Year: 1985

Abstract:
This report overviews major water quality patterns and trends for the Athabasca River and its major tributaries. In doing so it compares water quality data with surface water quality objectives, identifies spatial and temporal patterns, defines major factors affecting water quality, characterizes the relationship between basin hydrology and water quality and identifies river reaches with similar water quality characteristics. The data analyzed for this overview assessment include historical water quality records collected since 1970 at three fixed station network locations (Jasper, Town of Athabasca and Ft. McMurray), and the results of six basin wide synoptic sampling surveys done seasonally during 1984 and early 1985. The historical data define long term trends, whereas the synoptic surveys provide information on spatial patterns. Results indicate that except for the St. Regis Pulp Mill at Hinton, point source effluents from municipal and industrial plants have no broadly based influence on river water quality. In almost all instances, tributary streams account for 90% or more of all measured constituent 1oadings. At low river flows the Hinton Pulp Mill does affect river water quality for a distance of 50 to 75 km. Many of the Alberta Surface Water Quality Objectives (ASWQUO) are regularly exceeded, however most of these exceedances are not attributable to point or nonpoint source impacts. These provincial objectives do not account for regional variations in natural water quality. Comparison with Environment Canada's use specific water quality objectives indicate Athabasca River water can be used for all beneficial uses except contact recreation, which is 1imited much of the year by low water temperatures and high turbidity. Certain objectives for aquatic life and wildlife are occasionally exceeded, however, these violations are due to natural causes and pending further investigation are not thought to be significant. Three water quality zones can be defined for the Athabasca River. The Foothills Reach, between Jasper Park boundary and Ft. Assiniboine, is characterized by fast flow and good overall water quality conditions. Alkalinity and hardness 1evels are elevated, reflecting the mountain origin of the water; yet the suspended solids, organic carbon and nutrient contents are low. The Hinton pulp mill is the only significant anthropogenic impact. Coal mining activity in the upper tributaries has no broad based effect on the mainstem river system. In contrast, very different water quality conditions are experienced in the river reach situated between Ft. McMurray and Lake Athabasca. Suspended solid 1evels are high much of the year, as are associated parameters like organic carbon, particulate nutrients and metals. These constituents are derived from upstream tributaries and channel re-suspension, rather than municipal or industrial effluents. The lower reach al so has a unique major ion chemistry created by loadings from the Clearwater River. The intermediate reach between Ft. Assiniboine and Ft. McMurray is a transition zone. Along this stretch, alkalinity and hardness levels decrease, while most other constituent concentrations increase due to tributary loadings. Based upon statistical analysis of the historical water quality database three distinct water quality seasons are defined. These include the ice cover interval, and two open water periods, from ice off to July 31 and August 1 to freeze-up. Water quality in the early openwater season is controlled by local and mountain snowmelt runoff and a rising hydrograph. The 1ate openwater season is affected by a falling hydrograph, summer rainstorms in the Interior Plains and maximum instream biological activity. Except for some tributaries the existing database adequately defines baseline water quality conditions throughout the basin. Future work should emphasize expansion of the fixed station water quality monitoring network, definition of river assimilation processes, development of basin specific water quality objectives, further work on trace organic compounds and more detailed definition of parameter inter-correlation and discharge dependence.