bluuebunny/crossref_metadata_2025 huggingface dataset:
A Canadian Perspective on Endocrine Disrupting Substances in the Environment
Authors: Servos Mark , Delorme Peter , Fox Glen , Sutciffe Roger , Wade Michael
Published: May 2018

Although reproduction and development are major endpoints for environmental and human health assessments in many federal government programs, growing concern about risks posed by endocrine disrupting substances (EDS) has highlighted the need to detect subtle effects mediated through endocrine systems. Internationally, screening and testing programs in the United States, Japan and Europe, and the activities of international agencies such as the OECD, will have a profound influence on how Canada will address this issue in the future. It is critical that Canada be proactive, identify knowledge gaps from a Canadian perspective, and anticipate international developments that may influence Canadian policy. The complexity and urgency of the EDS question spurred the Five Natural Resource Departments Endocrine Disrupting Substances (5-NR EDS) Working Group to hold a multi-departmental, multi-stakeholder, workshop to address key issues in assessing risks of EDS to Canadians and the Canadian environment. The following is a summary of the major conclusions, research priorities and recommendations from the workshop held at the Grandview Inn, in Huntsville, Ontario, February 13–17, 2000.
Short-Term Effects of Low pH on the Microfauna of an Activated Sludge Wastewater Treatment System
Authors: Baldwin Damian D. , Campbell Christine E.
Published: May 2018

Optimum pH for biological (e.g., activated sludge) wastewater treatment is stated to lie between pH 6.5 and 8.0; however, the pH of processed effluent from thermomechanical pulp mills is closer to 4.5 and 5.5. Consequently, pH adjustment of effluent is required with associated costs. The ability of the microfaunal community (protozoa and metazoa) of activated sludge to survive at pH levels below 6.5 was evaluated with samples collected from Corner Brook Pulp and Paper Ltd. (Newfoundland, Canada). Effect of pH was examined at “high pH” (4.5, 5.5 and 6.5 control) and “low pH” (2.5, 3.5 and 6.5 control) under “summer” temperatures of 30°C and “winter” temperatures of 15°C, with impacts assessed after 1 h and 24 h exposure. Effect of pH was found to be temperature-dependent: pH levels down to 4.5 appeared to have little impact on microfaunal abundances at 30°C , but a number of microfauna were negatively affected at 15°C. Low pH levels of 2.5 and 3.5 were detrimental to the population densities of most microfauna. Adverse pH effects were more marked with increased exposure in some cases. An acid-neutralizing ability may be inherent in the activated sludge, as treatment pH increased over 24 h.
Pulp and Paper Environmental Effects Monitoring in Canada: An Overview
Authors: Walker Sherry L. , Hedley Kathleen , Porter Edward
Published: May 2018

Environmental effects monitoring (EEM) is a requirement for pulp and paper mills in Canada discharging effluent directly into receiving environments under the Pulp and Paper Effluent Regulations of the Fisheries Act. The objective of the EEM program is to assess effects on fish, fish habitat and the use of fisheries resources by humans, potentially affected by the deposit of mill effluent in aquatic receiving environments. The information provided by the monitoring program will contribute to assessing the adequacy of the regulations. Difficulties encountered in the first round of monitoring led to an extensive science review of key components and resulted in improvement to process, scientific defensibility of the monitoring data and site-specific flexibility of the EEM program. The second cycle of EEM was, overall, markedly more successful than Cycle 1. However, problems were still evident for fish surveys conducted in marine and estuarine environments. The adoption of improved alternative monitoring approaches (e.g., caged bivalves, mesocosms) should alleviate many of these problems. An overview of the EEM program, results to date, alternative monitoring approaches, and research priorities to fill data gaps are presented.
Effluent Characterization, Water Quality Monitoring and Sediment Monitoring in the Metal Mining EEM Program
Authors: Parker Roy , Dumaresq Charles
Published: May 2018

The metal mining Environmental Effects Monitoring (EEM) program will require mines to conduct effluent characterization and water quality monitoring on an ongoing basis. Samples will be collected four times a year, and will be analyzed for a range of parameters. This information will be used to aid in the design and interpretation of fish surveys and benthic invertebrate community surveys. There are also a number of water quality monitoring methods that may be used to help determine the cause of any effects identified by the EEM program. Mines will also be required to collect sediment samples for determination of particle size distribution and total organic carbon. This information will be used in the design and interpretation of benthic invertebrate community surveys. A range of sediment monitoring techniques are available to aid in the determination of the causes of effects on the benthic invertebrate community.
Trends in the Distribution of PCBs Compared to PACs in Sediments and Mussels of Halifax Harbour
Authors: Hellou Jocelyne , King Thomas L. , Steller Sean E. , Yeats Philip
Published: May 2018

Surficial sediments and blue mussels (Mytilus edulis) were collected around the perimeter of Halifax Harbour. Samples were analyzed for the presence of polychlorinated biphenyls (PCBs), ranging from mono- to decachloro congeners, and results compared to the presence of polycyclic aromatic compounds (PACs). The objective was to explore the relationship between contaminant profiles in sediments and in mussels, and the possibility of deducing their sources, patterns of deposition, circulation and bioavailability. IUPAC hexachlorobiphenyls 138/158/160/163 (unresolved) and 153/132/168 were the most abundant congeners in both sets of matrices, ranging in concentration between <0.5 to 46 and 4.5 to 25.5 ng/g (dry weight) in sediments and mussels, respectively. PCBs profiles point to a combination of commercial sources superimposed on some weathering. Biota-sediment accumulation factors (BSAF, concentration in mussels, dry weight/concentration in sediments, dry weight, and lipid/TOC normalized) varied throughout the harbour and per congener. Some similarities were observed between the most contaminated sites previously analyzed for PACs and presently analyzed for PCBs, while BSAF were highest at the entrance to the harbour, for PACs and PCBs.
Complying with Effluent Toxicity Regulation in Canada
Authors: Kovacs Tibor , Gibbons J. Sharon , Naish Valerie , Voss Ron
Published: May 2018

A questionnaire was sent to 75 mills in Canada requesting information on compliance in 1999 with respect to the toxicity regulation for liquid discharges. This regulation requires that at least 50% of rainbow trout and Daphnia magna survive in the discharge from the mill in toxicity tests. Of the 74 mills that responded, 81% and 74% reported no toxicity failures for process effluents in rainbow trout and Daphnia magna tests, respectively. For mills with infrequent or no toxicity episodes during the year (1 or 0 for trout; 1–4 or 0 for Daphnia magna), 89% and 92% of the mills met this criterion for trout and Daphnia magna tests, respectively. In addition to process effluents, 28 mills had separate cooling water discharges and, of these, ten experienced at least one episode of cooling water toxicity. Ammonia and accidental spills were most frequently cited by the mills as likely causes of process effluent toxicity. The most frequent causes cited for cooling water toxicity were chlorine and accidental contamination from other sources.
Vers une méthode de mesure du transfert d'oxygène en biofiltres
Authors: Amiel Christophe , Gillot Sylvie , Roustan Michel , Héduit Alain
Published: May 2018

L'objectif du travail présenté était d'une part de préciser les conditions d'adaptation aux biofiltres des méthodes de mesure “usuelles” en eau claire du transfert d'oxygène, d'autre part, de déterminer si l'addition de cobalt pouvait être évitée pour ralentir l'oxydation du sulfite. Trois méthodes de mesure ont été mises en oeuvre en eau claire et comparées sur colonne à bulles et en pilote biofiltre : la méthode de réoxygénation, la méthode des bilans gazeux et la méthode du dosage du sulfite. Les essais réalisés à différents débits d'air en présence d'une forte concentration en sulfite de sodium (2000 mg.L-1) ont montré que l'ajout de cobalt induisait un important facteur d'accélération du transfert d'oxygène. En milieu diphasique, la méthode des bilans gazeux (sans ou avec cobalt) fournit des résultats comparables à la méthode de référence (réoxygénation avec cobalt). Dans les conditions expérimentales, la méthode du dosage de sulfite fournie des résultats sous estimés. En pilote biofiltre, la méthode la mieux adaptée pour l'estimation du rendement d'oxygénation global en eau claire est la méthode des bilans gazeux sans addition de cobalt.
Sulfate Removal from Water
Authors: Darbi Ashref , Viraraghavan Thiruvenkatachari , Jin Yee-Chung , Braul Larry , Corkal Darrell
Published: May 2018

Sulfate occurs naturally in groundwater. Concerns regarding the health effects from sulfate in drinking water have been raised because of reports that diarrhea may be associated with water that contains high levels of sulfate. In the livestock production industry, there is a concern that high levels of sulfate in water can adversely affect productivity. Different methods can be used to remove sulfate from water. Proven technologies are ion-exchange, nanofiltration, reverse osmosis, and electrodialysis. A few earlier studies have shown that the use of bentonite/kaolinite for sulfate removal has produced encouraging results. Experimental work was undertaken to examine in detail the feasibility of such processes. Laboratory studies using bentonite showed poor or no removal in the case of high sulfate water. Ion exchange and nanofiltration were found to be very effective in removing sulfate. Ion exchange is likely to be more reliable than nanofiltration because of the sensitivity of the nanofiltration process to total dissolved solids and biofouling.
An Assessment of Variability of Pulp Mill Wastewater Treatment System Bacterial Communities using Molecular Methods
Authors: Baker Christopher J.O. , Fulthorpe Roberta R. , Gilbride Kimberley A.
Published: May 2018

The DNA fingerprinting techniques, 16S-restriction fragment length polymorphism (16S-RFLP), ribosomal intergenic spacer analysis (RISA) and repetitive extragenic palindrome PCR (Rep-PCR), were used for analyzing the bacterial communities of seven pulp and paper wastewater treatment systems. All three methods generate DNA fingerprints that can be compared using the computer-assisted program, Gelcompar©. Community similarity coefficients were based on quantitative determinations of both the positions of the DNA bands and the band intensities in order to compare the relative differences in the populations. Unique 16S-RFLP DNA fingerprints were observed for each mill suggesting that individual mills contained phylogenetically different communities. However this method was not sensitive enough to detect differences within a mill treatment system from different locations or from different sampling times. The RISA method, which generated more complex fingerprints than 16S-RFLP, could, for some mills, discern differences between samples. The Rep-PCR technique, however, showed the highest degree of resolution and produced not only distinct patterns for each mill but also distinct fingerprints for the temporal and spatial samples from some of the treatment systems. The sensitivity of this method might potentially be used to monitor the stability of the bacterial community within a secondary treatment system.
Binding of Hydrophobic Organic Contaminants to Humalite-Derived Aqueous Humic Products, with Implications for Remediation
Authors: Van Stempvoort Dale R. , Lesage Suzanne , Steer Helena
Published: May 2018

In order to assess the potential of commercial humic products in environmental remediation, their binding to heptachlor, hexachlorobenzene, hexachloroethane, 1,2,4-trichlorobenzene and n-hexane was measured. The binding was similar in tests with two colloidal-phase humic products prepared from humalite (naturally occurring, oxidized organic deposits found adjacent to coal) from Alberta, Canada (Luscar Ltd.). There were minor or negligible changes in binding strength for these two products over the full range of aqueous concentrations tested (1.67 to 33.4 g organic C/L), and for Aldrich humic acid. Aldrich humic acid was a stronger binder of the hydrophobic organic compounds than the two Luscar humic products, by factors of approximately 3 to 7. The binding of hydrophobic organics to the two Luscar humic products was similar in strength to that predicted for humic substances that occur in natural aquatic environments. Our binding data suggest that the use of concentrated Luscar humic products as colloidal-phase flushing agents would increase the aqueous concentrations of some hydrophobic organic contaminants in soils or aquifers by up to several hundred fold.
Physiological Response of Rainbow Trout to Sediment Released during Open-Cut Pipeline Water Crossing Construction
Authors: Reid Scott M. , Isaac Glenn , Metikosh Serge , Evans Jim
Published: May 2018

The physiological response of rainbow trout exposed to elevated suspended sediment concentrations downstream of two open-cut pipeline water crossings was investigated. Trout held in cages downstream of construction had increased respiration rates and shorter times till loss of equilibrium during sealed jar bioassays. Differences in blood hematocrit levels between experiments and transects is attributed to sediment concentration and particle size. Sediment exposure did not result in gill damage or fish mortality. The observed level of physiological effect was consistent with the predictions of the sediment-effects dose-response equation for salmonids.
Impact of Proposed Burlington and Hamilton Sewage Discharges in Western Lake Ontario
Authors: Rao Yerubandi R. , Murthy Raj C. , Chiocchio Fausto , Skafel Michael G. , Charlton Murray N.
Published: May 2018

The alternate strategy of open-lake discharge may alleviate the need for unusually stringent treatment needed to meet water quality goals of the Hamilton Harbour Remedial Action Plan (RAP). The latest update of the RAP recommended a study of the possibility of offshore discharges. A study conducted for the City of Burlington has proposed a location for outfall in Lake Ontario. This paper utilizes a combination of physical limnological data and mathematical models to predict the waste plume characteristics for the proposed outfall in the lake. Near-field dilutions obtained from a mixing zone model show that, for treated effluents with a discharge condition of 2 m3/s at the proposed outfall site at Burlington, the dilution ratios are in the range of 13:1 to 28:1 for weak to moderate currents during summer stratification. Winter dilution ratios increased to 21:1 to 96:1 for moderate currents. The recommended site for open-lake outfall provides acceptable near-field dilutions for treated effluents under typical lake currents and density structure. The extension of outfall to a location farther offshore is only marginally beneficial. With the proposed Burlington outfall location and discharge conditions, no far-field contamination is observed near the beaches or nearby water intakes for typical summer and winter conditions. Thus, this study indicates that by discharging the treated sewage from an outfall in Lake Ontario it is possible to achieve the Hamilton Harbour RAP goals.
An Investigation on the Use of Venturi Weirs as an Aerator
Authors: Baylar Ahmet
Published: May 2018

The most classic example of a hydraulic structure where gas transfer occurs is a weir. Transfer of gases between the atmosphere and river water can occur in a free overfall jet from a weir. A free overfall jet from a weir plunging into downstream water causes entrainment of air bubbles if the free overfall jet velocity exceeds the critical value where aeration occurs. This paper investigates the free overfall jets from Venturi and rectangular notch weirs and their effect on air entrainment rate. A Venturi weir was placed at the upstream channel end in order to increase the flow velocity of the free overfall jet and, in turn, to increase air entrainment. It was demonstrated that the air entrainment rate of the Venturi weir is significantly better than the rectangular notch weir, and this advantage becomes more pronounced as the throat width of the Venturi weir is decreased. These results demonstrated that Venturi weirs can be used as highly effective aerators in streams, rivers, constructed channels, fish hatcheries, water treatment plants, etc. Moreover, a regression equation was obtained for the Venturi weirs, relating air entrainment rate to unit discharge, weir crest width, drop height and throat width of Venturi weir. There was good agreement between the measured air entrainment rates and the values computed from the predictive equation.
Use of QSARs to Promote More Cost-Effective Use of Chemical Monitoring Resources. 1. Screening Industrial Chemicals and Pesticides, Direct Food Additives, Indirect Food Additives and Pharmaceuticals for Biodegradation, Bioconcentration and Aquatic Toxicity Potential
Authors: Walker John D. , Knaebel David , Mayo Kelly , Tunkel Jay , Gray D. Anthony
Published: May 2018

Monitoring studies are expensive to conduct. To promote more cost-effective use of chemical monitoring resources, quantitative structure activity relationships (QSARs) are proposed as methods to identify chemicals that could be found in, and cause adverse effects to, organisms in water, sediment and soil from the Great Lakes basin. QSARs were used to predict the biodegradation, bioconcentration and aquatic toxicity potential of 2697 industrial chemicals and pesticides, 1146 direct food additives, 967 indirect food additives and 282 pharmaceuticals that could be released to the Great Lakes basin. The QSARs identified 47 industrial chemicals and pesticides, 20 direct food additives, 13 indirect food additives and 7 pharmaceuticals with bioconcentration or aquatic toxicity potential or potential to not biodegrade readily. Most of these chemicals were predicted to partition to sediments. Using QSARs to identify chemicals with potential to persist, bioconcentrate or partition to sediments will promote more cost-effective use of chemical monitoring resources by allowing researchers to focus their analytical techniques on measuring chemicals predicted to persist in water or soil, bioconcentrate in fish or partition to sediments so that the effects of these chemicals can be assessed on indigenous organisms.
Microbiological Quality and Genotypic Speciation of Heterotrophic Bacteria Isolated from Potable Water Stored in Household Tanks
Authors: Tokajian Sima , Hashwa Fuad
Published: May 2018

Upon storage, a statistically significant increase in heterotrophic plate count (HPC) was detected in samples from household tanks. The most consistent correlate of regrowth was found to be storage time, however, temperature and the microbiological quality of the influent water were also important. Total and fecal coliforms were detected in the influent water and in the household storage tanks. Coliforms growing at 37°C were a small but significant part (about 0.002%) of the total heterotrophic population. In the influent, 92% of the coliforms (11 colony forming units/100 mL) at 44°C were Escherichia coli, while in the household tanks it was 86%. The majority of isolates from the influent and the household tanks recovered on R2A agar formed pigmented colonies and were Gram-negative belonging to the α-, β-, and γ-subclasses of Proteobacteria. Overall, the α-subclass was the dominant type representing 61% of the recovered HPC, and 40 to 50% of the organisms based on 16S rDNA sequence analysis were members of the family Sphingomonadaceae. The presence of E. coli and the isolation of opportunistic pathogens as a significant part of the HPC population from both influent and household tanks indicated a potential health hazard to consumers.
Lessivage des fluorures et des métaux a partir d'une cendre à charbon
Authors: Moufti Ahmed , Mountadar Mohammed
Published: May 2018

Le lessivage des fluorures à partir des cendres volantes a été étudié à différentes conditions (taux de cendre/eau distillée, température variable et pour un intervalle du pH bien précis). Les teneurs des éléments en traces dans les eaux de lessivage ont été également évaluées. Dans cette étude, on démontre que le lessivage dépend principalement de la température et du pH. A température ambiante (22°C) et à des pH supérieurs à 4.5, on a moins de lessivage du F- et des métaux à l'état de trace. Pour des pH acides (pH < 2,5), la teneur en fluorures est influencée par la réaction de complexation avec Fe3+ et Al3+. Cette étude a montré que le calcium est combiné avec les carbonates et la majorité des métaux sont sous formes des sulfates.
Origin of Salinity of the Shallow Aquifer of Guelmime, South Morocco: Hydrogeochemical Study
Authors: Bouhlassa Saidati , Aiachi Abdelkader
Published: May 2018

The economy of the Guelmime region is primarily dependent on agriculture and herding. Population growth and economic development result in an increase in water demand and the generation of additional pollution sources. The shallow aquifer of Guelmime is the main reservoir for drinking water supplies and plays a major role in the local economy. The aquifer corresponds geologically to a tectonic depression with Plio-Quaternary fill. In the aquifer, groundwater is characterized by chemical facies of type: Mg-HCO3, Mg-Cl and Na-Cl. The spatial distribution of total dissolved solids (TDS) shows a widening gradient with an increase in salinity downstream of the Oumlaachar and Seyyad sub-basins.

The primary processes controlling groundwater evolution in the basin-fill aquifer, using hydrogeochemical analysis of the behaviour of major ions, are: (i) dissolution of evaporites of the Plio-Quaternary formations, (ii) dedolomitization phenomena, and (iii) the return flow of irrigation.
Development and Survivorship of Northern Leopard Frogs (Rana pipiens) and Green Frogs (Rana clamitans) Exposed to Contaminants in the Water and Sediments of the St. Lawrence River near Cornwall, Ontario
Authors: McDaniel Tana V. , Harris Megan L. , Bishop Christine A. , Struger John
Published: May 2018

High levels of contamination in the aquatic environment and wildlife within the Ontario portion of the St. Lawrence River at the Cornwall Area of Concern (AOC) have raised questions about potential impacts on wildlife health. Northern leopard frog embryos were raised in two wetland sites within the AOC and at two reference sites to assess differences in water and sediment quality on survivorship and deformity rates. Chlorinated hydrocarbons (total polychlorinated biphenyls, organochlorine pesticides), polycyclic aromatic hydrocarbons, nutrients and heavy metals were measured in sediment and/or water from the study sites. Levels of some metals such as aluminium, cadmium, chromium and copper, exceeded federal and provincial guidelines for the protection of aquatic life, especially in the two AOC wetlands. Early stage tadpole survivorship was significantly lower and deformity frequency significantly higher at wetlands within the AOC; however, differences were likely not biologically significant. Survivorship and deformity rates of leopard frogs (Rana pipiens) at metamorphosis did not differ significantly among sites. Onset of metamorphosis was accelerated in tadpoles raised in wetlands within the AOC. Tadpoles raised in wetlands within the St. Lawrence River AOC took significantly less time to complete metamorphosis (53–55 days) than did tadpoles raised at reference sites (61–64 days). The phenology of metamorphosis was also more synchronous in tadpoles raised in the AOC, with all tadpoles reaching metamorphosis within a space of 3 to 7 days, as compared to 9 to 12 days at reference wetlands; these differences could not be accounted for by water temperature. Differences in development and survivorship rates between AOC and reference sites may be related to contaminant concentrations in water and sediment. However, no strong evidence for beneficial use impairment in terms of reproductive impairments or elevated deformity rates were seen from caged leopard frogs in the two AOC wetlands.
Comparison of Mercury and Lead Sediment Concentrations in Lake Ontario (1968-1998) and Lake Erie (1971–1997/98) using a GIS-Based Kriging Approach
Authors: Forsythe K. Wayne , Dennis Michael , Marvin Chris H.
Published: May 2018

This research analyzed sediment contamination concentrations for mercury and lead in Lakes Ontario and Erie using a GIS-based kriging approach. Environment Canada provided sediment survey data for Lake Ontario (1968 and 1998) and Lake Erie (1971 and 1997/98). Collation and mapping of point measurement data without the application of interpolation methods does not allow for spatial data trends to be fully analyzed. The kriging technique enables the creation of interpolated prediction surfaces, with the advantage that the results can be statistically validated. Although data normality is not required, the kriging results for the historical datasets suggest that it may be desirable, as statistical validity was reduced due to some individual stations having very high contaminant concentrations. Three of the four models developed for the 1997/98 data were statistically valid. For both lakes, the more recent data reveal reduced concentrations of mercury and lead, and there has been an overall reduction in contamination levels. However, sediments in some areas still exceeded Canadian sediment quality guidelines. The areas of greatest sediment contamination in Lake Ontario were within the major depositional basins, presumably as a result of historical industrial activities in watersheds along the southern and western shoreline including the Niagara River. In Lake Erie, areas of greatest sediment contamination continue to be located in the western and south central portions of the lake in proximity to the Detroit River and major urban/industrial centres.
An Automated Headspace SPME-GC-ITMS Technique for Taste and Odour Compound Identification
Authors: Furtula Vesna , Davies John-Mark , Mazumder Asit
Published: May 2018

A simple, automated and efficient method is presented for routine analysis of taste and odour compounds in water samples. The following compounds were investigated: hexanal, heptanal, 2t,4t-heptadienal, 2t,4t-octadienal, 2t,6t-nonadienal, 2t,6c-nonadienal, 2-methylisoborneol (MIB), 2t,4t-nonadienal, β-cyclocitral, 2t,4t-decadienal, geosmin and β-ionone. Headspace solid-phase microextraction (SPME) coupled with gas chromatography (GC) and low-resolution ion-trap mass spectrometry (ITMS) was used for quantification of these compounds. A 65-µm polydimethylsiloxane/divinylbenzene (PDMS/DVB) fibre was used for headspace SPME analysis. Method detection limits for all compounds analyzed are at the ng/L level and are lower in most cases than sensory analysis can detect. The method was employed for the analysis of lake and reservoir water samples from several coastal British Columbia drinking water sources during the summer of 2001. Geosmin was the only compound detected and was found at concentrations up to 26 ng/L. To our knowledge the method presented is unique in terms of full automation and represents a sensitive and efficient tool for studying and monitoring taste and odour compounds in water sources.
Removal of Vat Dyes from Textile Wastewater Using Biosludge
Authors: Sirianuntapiboon Suntud , Saengow Weerapong
Published: May 2018

Biosludge from a wastewater treatment plant was able to adsorb colourants, particularly vat dyes, from textile wastewater. Autoclaved and resting biosludge showed different adsorption abilities with different types of vat dyes. The adsorption ability of the biosludge increased with an increase in sludge age (solid retention time; SRT). Autoclaved biosludge showed the highest adsorption ability under acidic conditions (pH 3) while the resting biosludge showed the highest adsorption ability under neutral or weak alkaline conditions. The maximum colourant (Vat Black 25) adsorption capacities of autoclaved and resting biosludge with a sludge age of 24 days were 85.54 ± 0.5 and 37.59 ± 0.6 mg/g biosludge, respectively. Using a sequencing batch reactor (SBR) system, the biosludge was able to remove both organic matter and colourants from both textile and synthetic textile wastewaters. The removal efficiencies of the system increased with an increase in SRT of the system. The removal efficiency of the system with textile wastewater was lower than with synthetic textile wastewater. The BOD5 and colourant removal efficiency of the SBR system with textile and synthetic textile industrial wastewaters under a BOD5 loading of 0.13 kg BOD/m3-d were 70.1 ± 4.4% and 84.9 ± 2.0%, and 98.1 ± 1.5% and 87.5 ± 5.1%, respectively.
Benthic Responses to Wet-Weather Discharges in Urban Streams in Southern Ontario
Authors: Grapentine Lee , Rochfort Quintin , Marsalek Jiri
Published: May 2018

Urban stormwater and combined sewer overflow (CSO) discharges are important sources of sediment and contaminants (trace metals, PAHs, nutrients and road salts), and cause changes in flow, sediment, chemical and thermal regimes of receiving waters. Over the past several years, benthic conditions of streams representing a range of exposure environments were assessed in Hamilton, Toronto, Oshawa and Kingston, Ontario. Studies progressed from initial surveys of sediment contaminant levels, sediment toxicity and benthic invertebrate community structure to more spatially intensive sampling and experimental approaches that included the use of artificial substrates, in situ water toxicity tests and measurements of contaminant bioaccumulation.

Results showed that while sediments and some biota at sites exposed to wet-weather discharges were often contaminated with metals and PAHs and enriched with nutrients, significant biological degradation measured by sediment toxicity or depauperated benthic communities was not evident. Exposure to stormwater discharges at sites below outfalls could alter the composition of benthic communities, but these effects were not strongly related to contaminant concentrations in sediment or invertebrate tissue. No outfall-associated toxicity was observed for caged amphipods held in the water column.

Effects of wet-weather discharges on benthic communities at the urban stream sites studied appear to be small, and their detection was limited by several inherent conditions, including natural heterogeneity in the distribution of benthic invertebrates, episodic (intermittent) exposure to discharges and contaminant fluxes allowing some recovery, “background” levels of disturbance, poorly delineated changes in communities caused by physical effects such as flow and sediment transport, and community response dynamics. Detection of stormwater discharge effects should be improved by sampling on smaller temporal and multiple spatial scales to better quantify stressor exposure and invertebrate responses.
Operational Monitoring of Urban Stormwater Management Facilities and Receiving Subwatersheds in Richmond Hill, Ontario
Authors: Olding Daniel D. , Steele Tracey S. , Nemeth John C.
Published: May 2018

Untreated stormwater discharge has been found to have major impacts on urban watercourses. Despite the acknowledgement of the importance of adopting broader-scale approaches to managing stormwater, there is limited information describing the subwatershed benefits of implementing numerous best management practices (BMPs). Operational monitoring of stormwater management facilities (SWMFs) and streams in three subwatersheds undergoing urbanization was undertaken over a five-year period to measure potential changes in suspended solids concentrations, hydrology and temperature. SWMFs at construction sites had elevated total suspended solids (TSS) discharges relative to facilities in stable catchments, but reduced TSS discharges in comparison to uncontrolled construction sites. The discharge from single facilities was found to have the potential to increase downstream watercourse TSS concentrations in headwater areas, but increases were often not detectable further downstream. TSS discharges from SWMFs in stable catchments were similar to published ranges, and were a useful tool to identify facilities that were not functioning as designed. Based upon the current subwatershed imperviousness levels, water quality impacts from cumulative SWMF discharges appear to be less likely to be significant than some other factors, such as the changes in the subwatershed hydrological response. No increase in peakflow or duration of midbankfull flow for the 25-mm and 2-year storm event and no trend in baseflow or water temperature were detectable over the study period, despite the increase in imperviousness due to watershed urbanization. The findings from this operational monitoring study suggest that implementation of BMPs may help to mitigate urban impacts at the subwatershed level.
Planning and Design of Combined Sewer Overflow Treatment
Authors: Zukovs George , Marsalek Jiri
Published: May 2018

A newly produced (2004) Combined Sewer Overflow (CSO) Treatment Technologies Manual provides an overview of practices in, and guidance for, planning, design and implementation of CSO treatment. Towards this end, the manual first addresses CSO abatement program planning in order to provide an overall framework within which the application and design of CSO treatment facilities may be considered. Following the establishment of a planning framework, guidance is provided for CSO treatment facility preliminary design, which encompasses such steps as the development of CSO control and treatment objectives, assessment of design flows, development of a treatment process train, site-specific considerations, and costs and operating and maintenance (O&M) factors. Finally, preliminary design considerations are developed in more detail for CSO retention treatment basins (RTBs), which are commonly applied to control and treat CSOs in the Great Lakes municipalities. Well-designed RTBs can meet the Ontario requirements for CSO pollution abatement and thereby contribute to the remedial action in the Great Lakes Areas of Concern.
High-Rate Retention Treatment Basins for CSO Control in Windsor, Ontario
Authors: Li Jian Guo , Horneck Harold , Averill David , McCorquodale J. Alex , Biswas Nihar
Published: May 2018

Experimental investigations were conducted to evaluate the effectiveness of a retention treatment basin (RTB) with polymer coagulation for the treatment of combined sewer overflows (CSO) at high hydraulic loading rates. The TSS removal efficiency of the pilot-scale RTB at a surface overflow rate (SOR) of 11 m/h was approximately 35% without chemical addition, and 80% with a polymer dosage range of 5 to 10 milligrams per gram of influent TSS. The results demonstrated that the use of polymer coagulation significantly improved TSS removal and allowed the SOR in the RTB to be significantly increased, resulting in smaller treatment units. An empirical relationship was established to estimate removal efficiencies as a function of overflow rate. The results also compared settling characteristics of CSO, obtained from long column tests, to removal efficiencies in the high-rate RTB.
The Limnology of Williston Reservoir: British Columbia's Largest Lacustrine Ecosystem
Authors: Stockner John , Langston Arne , Sebastian Dale , Wilson Greg
Published: May 2018

In surface area, Williston Reservoir is British Columbia's largest lacustrine ecosystem. The reservoir shows remarkably little spatiotemporal variance among its three major reaches (Finlay, Parsnip and Peace), despite the immensity and biogeoclimatic diversity of its drainage basins. Williston is ultra-oligotrophic with average concentrations of total dissolved phosphorus (TDP) ranging from 3 to 5 µg/L and nitrate-nitrogen (NO3-N) from 60 to 65 µg/L. The pelagic plankton community of Williston Reservoir is dominated by bacteria, pico-cyanobacteria, nano-flagellates and small diatoms, and the zooplankton community is comprised largely of copepods in spring and small cladocerans in summer and fall. Primary production rates are very low and most carbon is produced by the pico- and nano-sized plankters that appear to be primarily light limited due to high turbidity and frequent wind-mixing episodes, i.e., shallow light compensation depth and deep epilimnetic depth. Microbial food webs are predominant in Williston through much of the growing season, with free-living bacteria and pico-cyanobacteria as the primary carbon template, and nano-flagellates, ciliates and micro-zooplankton as the principal grazers. Loading models indicate that after impoundment in 1968, Williston was initially a moderately productive ecosystem, but the system has progressively lost nutrients, namely P, through sedimentation and outflow, but also by the scarcity of littoral carbon production due to severe water level fluctuations (drawdown) and winter ice-scouring. Hence, within the past 2 to 3 decades the ecosystem has gradually lost biogenic productive capacity and now lies within the ultra-oligotrophic trophic status and supports a low level of fish production. Daily rates of carbon production are presently at levels more typical of British Columbia fast-flushing, ultra-oligotrophic coastal ecosystems than large, interior-type oligo- and mesotrophic British Columbia lakes. Based on average values of most limnological variables we demonstrate that the Finlay Reach is currently the most productive region of Williston, and estimates of pelagic fish from hydroacoustic/trawl and gillnet surveys support this contention.
Comparison of Oxygen Transfer Parameters from Four Testing Methods in Three Activated Sludge Processes
Authors: Mahendraker Venkatram , Mavinic Donald S. , Rabinowitz Barry
Published: May 2018

In this investigation, the mass transfer of oxygen was determined using four different testing methods in three activated sludge processes, as per the guidelines established by the American Society of Civil Engineers (ASCE 1997). The testing methods applied included the steady-state oxygen uptake rate (OUR), the non-steady-state changing power level (CPL), the non-steady-state hydrogen peroxide addition (HPA) and the off-gas methods. The analysis indicated that steady-state OUR and off-gas methods resulted in comparable estimates of oxygen transfer parameters, with somewhat higher variations observed in the data from the off-gas method. The application of HPA and CPL methods produced variable results under the same process conditions and these testing methods affected the process. Based on the comparative evaluation conducted in these controlled experiments, the validity of HPA and CPL tests to measure the oxygen transfer under process conditions is questionable. Overall, the off-gas method appears to be superior, as it does not require steady-state process conditions. However, under suitable conditions the steady-state OUR method may be an economical option to study oxygen transfer under process conditions.
Application of Multi-stable Isotope (13C, 15N, 34S, 37Cl) Assays to Assess Spatial Separation of Fish (Longnose Sucker Catostomus catostomus) in an Area Receiving Complex Effluents
Authors: Dubé Monique G. , Benoy Glenn A. , Blenkinsopp Sandra , Ferone Jenny-Marie , Brua Robert B. , Wassenaar Leonard I.
Published: May 2018

Incorporation of stable isotope analysis (SIA) into routine environmental effects monitoring programs of receiving waters may enable determination of the spatial extent of biotic exposure and discrimination among sources of complex effluents. To evaluate this hypothesis, longnose sucker (Catostomus catostomus) were collected from four sites along the Athabasca River, Alberta (upstream reference site, two sites downstream of effluents from two pulp and paper mills, and a site downstream of effluent from a municipal sewage treatment plant). Stable isotopes of carbon, nitrogen, sulfur and chlorine were analyzed in bone, gonad, liver and white muscle tissues of the fish. In general, most sites and tissues differed according to δ13C, δ15N and δ34S values. Also, an interaction between site and tissue was observed for δ15N values. A better insight into the usefulness of stable isotopes was obtained through the use of multivariate discriminant function analysis. δ15N and δ34S signatures of gonad and liver tissues of males were most effective at classifying fish according to site (~70% for both tissues). For all tissues except bone, fish from the upstream reference site were most separable from all others, especially females. δ37Cl values for female gonads and male livers were related to sites downstream of the pulp and paper mills. Future research should routinely include SIA of fish tissues, but also of effluents, receiving waters and food web components to better resolve links between specific effluents and fish exposure.
Heavy Metal Concentrations in some Biotic and Abiotic Components of the Olezoa Wetland Complex (Yaoundé-Cameroon, West Africa)
Authors: Fonkou Théophile , Agendia Philip , Kengne Ives , Akoa Amougou , Derek Focho , Nya Jean , Dongmo Francois
Published: May 2018

Concentrations of cadmium (Cd), copper (Cu), zinc (Zn) and lead (Pb) in water, sediments, fish organs and plants from two ponds of the Olezoa wetland complex were analyzed. Plants investigated were Cyperus papyrus, Enydra fluctuans, Ipomoea aquatica and Echinocloa pyramidalis. The fish species studied was the walking catfish Clarias lazera and the heavy metal concentrations were measured in the digestive tract, gills, flesh and liver. Average concentrations in water were 6 x 10-2 ppm for Cd, 14.53 ppm for Cu, 2.88 ppm for Zn and 17.69 ppm for Pb. These values were low compared to those recorded in the sediments, plants and fish organs. Results revealed an increase of heavy metal concentrations from water to plants and fish organs, with magnification factors ranging from 580 to 5700 and from 577 to 8173, respectively. In the sediments and the floating mat of the eutrophic fish ponds, these factors ranged from 491 to 1065 and 624 to 758, respectively. In the fish organs, particularly, the following accumulation gradients were foreseen: gills Ŵ flesh Ŵ digestive tract Ŵ liver for Cd and Pb; and flesh Ŵ gills Ŵ digestive tract Ŵ liver for Cu and Zn. The four plants studied appeared to be good candidates for phytoremediation of water metal pollution. The quantity of heavy metals in this wetland complex is considerable and will constitute a potential hazard for biota.
Studies on the Use of Fortified Kaolinitic Soil-Clay in Industrial Wastewater Treatment
Authors: Oladoja Nurudeen A. , Asia Imohimi O.
Published: May 2018

This study aimed to design an uncomplicated, reliable, technologically simple and low energy consuming decentralized wastewater treatment system using kaolinitic soil-clay fortified with stone pebbles to enhance the permeability to water. Soilclay samples were obtained from different deposits in Nigeria viz: Auchi (AU), Ozanagogo (OZ) and Ubulu-Uku (UB). The geochemical analysis of the soil-clay samples was done using an atomic absorption spectrophotometer (AAS). The mineralogical analysis, studied with an X-ray diffractometer, revealed the presence of kaolinite as the domineering clay mineral present. Illite was also found in the clay OZ and AU (6.50% and 0.50%, respectively). Composite wastewater samples were obtained from brewery, textile and polymer industries. Performance efficiency studies were conducted to determine the best combination ratio of pebbles/soil-clay. Soil-clay fortified with pebbles in combination ratios of 1:3 (i.e., pebbles: soil-clay = 1:3 [w/w]) showed optimum water treatment while the combination 3:1 gave the least. The flow rate studies showed that the wastewater had a longer residence time in non-fortified soil-clay than in fortified soil-clay. Two modes of treatment methods were employed: single and double column treatment (SCT and DCT). The two methods gave effluents with goodquality characteristics but those from the DCT were of better quality. The quality of effluents also varied from one fortified column to another. The fortified column containing OZ exhibited the best performance while UB showed the least performance in the entire treatment processes. Results obtained from the studies on the effects of repeated use on the performance efficiency of the fortified soil-clay showed that the pH of effluents decreased with time toward acidity; the amount of TS also decreased with time; and, as the COD value increased, depletion in the DO was also recorded.
Treatment of Sago Wastewater using Hybrid Anaerobic Reactor
Authors: Banu J. Rajesh , Kaliappan Sudalyandi , Beck Dieter
Published: May 2018

Sago, tapioca starch, is manufactured by over 800 small-scale units located in the Salem district of the State of Tamilnadu, South India. These units generate large quantities of high-strength wastewater requiring elaborate treatment prior to disposal. The present study is an attempt to treat the sago wastewater using a hybrid reactor, which combines the advantages of both fixed-film and up-flow anaerobic sludge blanket systems. A hybrid reactor with a volume of 5.9 L was operated at organic loading rates varying from 10.4 to 24.6 kg COD/m3d. After 120 d of start-up, an appreciable decrease in COD and efficient removal of solids were evident. The COD removal varied from 91 to 83%. While the removal of total solids was in the range of 56 to 63%, that of volatile solids varied from 67 to 72%. The methane production during the study period was in the range of 0.11 to 0.14 L CH4/g COD-d and the percentage was from 55 to 67%. The ideal organic loading rate (OLR) was determined on the basis of tolerance of the reactor towards higher organic loading rate and it was found to be 23.4 kg COD/m3d. The findings of the study open new possibilities for the design of low-cost and compact on-site treatment systems with very short retention periods.
Comparison of Analytical Techniques for Analysis of Arsenic Adsorbed on Carbon
Authors: Yadav Nirbhay Narayan , Maheswaran Saravanamuthu , Shutthanandan Vaithiyalingam , Thevuthasan Suntharampillai , Hart Todd R. , Ngo Huu Hao , Vigneswaran Saravanamuthu
Published: May 2018

Activated carbon (AC) has been used extensively to treat arsenic-contaminated groundwater for a number of years. To date, attempts to quantify directly the amount of arsenic removed by the activated carbon using nondestructive methods has been limited. High-energy ion beam based proton induced x-ray emission (PIXE) is ideally suited to investigate the issues regarding the quantification of trace metals in solids. In this study, after the adsorption of arsenic on activated carbon, arsenic concentration in granular activated carbon (GAC) and powder activated carbon (PAC) were quantified using PIXE. The PIXE results were compared with atomic absorption spectrometry (AAS) and inductively coupled plasma optical emission spectrometry (ICP-OES) measurements. Some differences are observed between these measurements. The differences are greater in the case of GAC compared to PAC. These differences are mainly due to the inhomogeneous structure of GAC and PAC, which includes the variable surface properties such as surface area and pore sizes in each granule or particle. The larger differences are mainly due to the increased particle dimensions of GAC compared to PAC and the nature of the internal pore structure of GAC, which results in different amounts of arsenic adsorbed on different granules of GAC or even in different regions of one granule. This inhomogeneity of arsenic concentration is clearly visible in the arsenic concentration map generated for a single GAC particle using microbeam PIXE.