bluuebunny/crossref_metadata_2025_split huggingface dataset:
60CO and 137CS Activity of Nearshore Lake Ontario Sediments in the Vicinity of the Pickering Nuclear Generating Complex
Authors: Rodgers D. W. , McKinley R. S. 
Published: March 2019

Abstract
Detectable 137Cs activity (&lt;1 - 27 Bq/kg dry wt.) was widely distributed in sediments from a series of nearshore transects along Lake Ontario near Pickering Nuclear Generating Station (NGS) ‘A’. In contrast, detectable 60Co activity (&lt;1 - 14 Bq/Kg dry wt.) was largely restricted to transects located near the discharge of Pickering ‘A’ NGS. The widespread distribution of 137Cs is consistent with diffuse input of the radionuclide through fallout, while the restricted distribution of 60Co indicates a localized input of this radionuclide. Adsorption distribution coefficients (Kd’s) of 60Co and 137Cs varied by more than an order of magnitude among representative sediments. Although Kd’s of both radionuclides were correlated with cation exchange capacity and particle size, neither the observed gamma activity nor the corresponding Kd were important in describing 60Co or 137Cs Kd’s. Thus factors other than adsorption affinity alone may be required to account for the distribution of these radionuclides in nearshore Lake Ontario sediments.
Evaluation of a Large-Volume Extractor for Determining Trace Organic Contaminant Levels in the Great Lakes
Authors: Neilson M. , Stevens R. 
Published: March 2019

Abstract
The design, shipboard operation and performance of a large-volume extractor is described. A total of 224 water samples were extracted at up to 1 L.min−1 with dichloromethane during monitoring cruises on lakes Ontario, Erie, Huron and Superior in the spring of 1986. To evaluate the performance of the extractor, a spiking solution containing surrogate standards was added during the course of the extraction. Five surrogate spikes were added in the field: endrinketone, 1,3-dibromobenzene, 1,3,5-tribromobenzene, 1,2,4,5-tetrabromobenzene and 2,3,5,6-tetrachlorobiphenyl. Extractor performance was evaluated for both ambient and centrifuged water samples using recovery and reproducibility as criteria. Analytical results could then be excluded on the basis of surrogate recoveries exceeding two standard deviations from the mean. Recoveries ranged from 89–130% and coefficients of variation were generally ≤25%.
Automation of a Petroleum Refinery Wastewater Treatment Plant:A Case Study
Authors: Shantz Robert J. , Erickson Virginia B. 
Published: March 2019

Abstract
Historically, automation was not considered for wastewater treatment plants because it did not significantly affect operating costs, and manual plant operation was considered acceptable. Despite past practices, the BP Oil Refinery at Marcus Hook, Pennsylvania set a new standard when they began upgrading their wastewater facility in 1985. By automating the plant, they ensured safe, reliable operation with minimum labor requirements, process optimization, and long-term reductions in operating costs. Major design features included: a distributed computer control system with monitoring and supervisory capabilities; high-quality control system instruments; control system components; and redundancy and backup to support operation if a component or power failure occurs. In addition, design control philosophies remained consistent from predesign to startup. This advanced wastewater treatment plant can serve as a model for automation of future industrial treatment facilities.
L’abattement des bactéries coliformes dans les étangs aérés facultatifs — 1. Cinétique, modélisation et variables biotiques
Authors: Leduc Roland , Nguyen Van-Thanh-Van 
Published: March 2019

Abstract
Cet article présente une revue de la cinétique, des modèles de conception et de l’influence des variables du type biotique qui concernent l’abattement des indicateurs de pollution d’origine fécale — en particulier les bactéries coliformes — dans les étangs aérés servant à l’épuration des eaux résiduaires d’origine municipale. L’article synthétise les modèles qui ont été proposés pour la cinétique de disparition des indicateurs fécaux dans les étangs, ainsi que les modèles de prédiction, à l’état permanent, des concentrations d’indicateurs dans l’effluent d’étangs, tant en régime hydraulique des types piston, mélange complet ou mélange intermédiaire. Aussi, les modèles statistiques sont discutés brièvement. L’article identifie les divers rôles que jouent les variables biotiques dans le phénomène d’abattement et dans les propriétés des indicateurs de pollution fécale. Plus spécifiquement, les effets qu’exercent les algues, les prédateurs, les coliphages, les oiseaux, les animaux et autres sur le procédé d’inactivation des entérobactéries, ainsi que le facteur R, sont passés en revue. Globalement, cet article fait l’état des progrès réalisés au niveau de la compréhension du phénomène de disparition naturelle des indicateurs fécaux, et identifie les directions de recherche qui semblent les plus nécessaires en vue d’améliorer les techniques d’analyse et les méthodes de conception des systèmes d’étangs.
Suivi d’une contamination pétrolière accidentelle dans l’estuaire moyen du Saint-Laurent: Le cas de l’Ile-aux-Grues
Authors: Siron R. , Pelletier E. , Brochu C. 
Published: March 2019

Abstract
Le sédiment superficiel (0-3cm), l’eau interstitielle, les particules en suspension et l’eau de surface autour de l’Ile-aux-Grues (Québec, Canada) ont été échantillonnés en mai 1988 (11 jours après le déversement du pétrolier Czantoria) et en juin 1990. Les concentrations en hydrocarbures totaux mesurées par spectrofluorescence révèlent l’enrichissement des particules en suspension relativement à la fraction dissoute et au sédiment. Les analyses en chromatographie en phase gazeuse montrent que la contamination pétrolière du sédiment a été très ponctuelle. En mai 88, seulement deux stations montraient les indices d’une forte contamination pétrolière du sédiment, qui n’était plus décelée significativement deux ans après. A l’une de ces stations, la biodégradation des hydrocarbures semblait très avancée dans le sédiment, alors que l’eau interstitielle était enrichie en dérivés naphtaléniques. Des résidus de type émulsions “d’eau-dans-1’huile” non altérés étaient retrouvés adsorbés sur des rochers aux deux extrémités de l’ile, 11 jours après l’accident. Dans le sédiment prélevé en mai 88, l’origine fossile des hydrocarbures se superpose à un “bruit de fond” dans lequel on peut distinguer une importante contribution biogénique (n-alcanes à chaînes impaires, rétène, pérylène). Durant les deux séries d’échantillonnage, tous les hydrocarbures aromatiques polycycliques (HAP) dérivés de combustion ont été retrouvés à des niveaux relativement faibles dans le sédiment, confirmant la légère contamination pyrogénique à laquelle le site étudié est soumis.
Chemical Composition and Metal Speciation in Porewaters from the Upper Qu’Appelle River Basin, Saskatchewan
Authors: Farrell Richard E. , Yang Jae E. , Huang P. Ming , Liaw Wen K. 
Published: March 2019

Abstract
Porewater samples from the upper Qu’Appelle River basin in Saskatchewan, Canada, were analyzed to obtain metal, inorganic ligand and amino add profiles. These data were used to compute the aqueous speciation of the metals in each porewater using the computer program GEOCHEM-PC. The porewaters were classified as slightly to moderately saline. Metal concentrations reflected both the geology of the drainage basin and the impact of anthropogenic activities. Whereas K and Na were present almost entirely as the free aquo ions, carbonate equilibria dominated the speciation of Ca. Mg and Mn (the predominant metal ligand species were of the type MCO3 (s). MCO30. and MHCO3+). Trace metal concentrations were generally within the ranges reported for non-polluted freshwater systems. Whereas the speciation of the trace metals Cr(III) and Co(II) was dominated by carbonate equilibria, Hg(II)-, Zn(II)- and Fe(II)-speciation was dominated by hydroxy-metal complexes of the type M(OH)+ and M(OH)2°. The speciation of Fe(III) was dominated by Fe(OH)3 (s). In porewaters with high chloride concentrations (&gt; 2 mM), however, significant amounts of Hg(II) were bound as HgCl20 and HgClOH0. The aqueous speciation of Al was dominated by Al(OH)4− and Al2Si2O4(OH)6 (s). Total concentrations of dissolved free amino acids varied from 15.21 to 25.17 umole L−1. The most important metal scavenging amino acids were histidine (due to high stability constants for the metal-histidine complexes) and tryptophan (due to its relatively high concentration in the porewaters. i.e., 5.96 to 7.73 umole L−1). Secondary concentrations of various trace metal-amino add complexes were computed for all the porewaters, but metal-amino acid complexes dominated the speciation of Cu(II) in all the porewaters and Ni(II) in two of the porewaters.
Boundary Layer Models for Inverse Estimates of Entrainment and Related Processes at the Sediment-Water Interface
Authors: Bedford K. W. , Wai O. W. 
Published: March 2019

Abstract
With entrainment estimation required for both field data analysis and models this paper provides a compendium of the theoretical concentration boundary layer models and auxiliary shear stress estimators required to invert for estimates of entrainment rates. The various models are roughly categorized by the type of forcing function treated and three categories are defined. Within each category, no effort is made to evaluate one model over another. The essential points are that one field deployment might require the use of all categories of models to cover the succession of forcing function responses at a particular site. Interfacial boundary conditions expressed in the form of bed concentration and shear velocity are summarized, especially with regard to the limits imposed by the assumptions used in the derivation.
Pesticides, Nitrate-N and Bacteria in Farm Wells of Kings County, Nova Scotia
Authors: Briggins David R. , Moerman Dennis E. 
Published: March 2019

Abstract
Water samples collected from 102 farm wells in the most intensively farmed region in Nova Scotia were analyzed for pesticides, nitrate-N and coliform bacteria. An additional 135 wells were sampled for nitrate-N only. None of the study wells contained pesticide concentrations above maximum acceptable concentrations for Canadian drinking water; however, very low pesticide levels were found in 41% of the wells. Atrazine was the most prevalent pesticide, occurring in 79% of the wells with detections. Nitrate-N and coliform bacteria exceeded the guidelines in 13 and 9% of the study wells, respectively. Statistical analysis of the data indicated that pesticide contamination was generally not related to well construction and surficial material parameters, but some correlations were found for nitrate-N and bacterial contamination. Case studies indicated that the majority of pesticide occurrences were attributable to nonpoint sources. Atrazine contamination may be the result of historic use rather than current agricultural practices.
Susceptibility of Groundwater to Pesticide and Nitrate Contamination in Predisposed Areas of Southwestern Ontario
Authors: Lampman Wray 
Published: March 2019

Abstract
Agricultural practices today employ a vast array of chemicals in large volumes in order to improve both the quantity and quality of our agricultural products. While it has long been recognized that runoff from agricultural land has the potential to degrade surface water quality, only recently has attention been focused on the effect of agricultural usage on groundwater. In order to study the effects of pesticides and nitrate usage on the quality of groundwater, in 1985 the Ontario Ministry of Environment and Energy began operating a groundwater monitoring program in southwestern Ontario.
Data generated from this program, which utilized sample data collected from both wells and piezometers, indicate that in areas of heavy pesticide and nitrate usage, shallow groundwater is continuously testing positive for nitrate and a variety of pesticides. Factors which influence the number of positive incidents for pesticides are directly related to the persistence of the chemical, its method of application, and the amounts utilized. Soil types and depth to groundwater, although influencing the time of detection, do not govern the number of detection events. Changes in agricultural practices are also monitored to see if pesticide reduction, a variation in the method of application, crop rotations and an increase in soil organic matter could influence the levels of pesticide It was found that when chemicals of a low persistence were applied post emergent at the minimum recommended rate, pesticides were not detected in the groundwater. Crop rotations were also effective in reducing the level of pesticides in groundwater. Tillage practices and increases in soil organic matter were also effective in reducing pesticide contamination.
It was found that when chemicals of a low persistence were applied post emergent at the minimum recommended rate, pesticides were not detected in the groundwater. Crop rotation and reduction in nitrate loadings were found to be the only effective methods to reduce nitrate loading to groundwater. It was also found that elevated levels of potassium and/or nitrate in groundwater serve as a reliable indicator of the groundwater susceptibility to pesticide contamination.
Remedial action to alleviate the impact of pesticides and nitrates in groundwater must focus on the chemical usage patterns employed on the farm site and an overall reduction of the quantities of pesticides and nitrates utilized. These patterns must incorporate a well-designed program of crop rotation with the proper utilization of these chemicals on site.
Stream Channel and Riparian Zone Rehabilitation in the Dauphin Lake Watershed, Manitoba
Authors: Gaboury M.N. , Janusz R.A. , Broughton K.E. 
Published: March 2019

Abstract
An extensive program of drain construction, stream channelization and diversion, begun in the early 1900s, expanded the area of cultivated, arable land within the Dauphin Lake basin. The developed drainage network altered flows, shortened natural streams, eliminated aquatic habitats, and caused channel erosion. The Stream Rehabilitation Program was developed in 1992 to rehabilitate riparian zones and unstable stream reaches within the seven major tributaries of the watershed. The rehabilitation strategy included stream condition assessments, improvement of the channel stability and aquatic habitats by reintroducing pool and riffle sequences, and involvement of landowners in the design and implementation of their on-farm riparian rehabilitation plans. Between 1993 and 1996, 36 km of straightened channels were rehabilitated using pool and riffle sequences, and 14 cooperating livestock producers implemented new farm layouts and practices. Under a signed stewardship agreement, landowners committed to maintain the project works and a minimum 10-m riparian corridor for at least 10 years. The Stream Rehabilitation Program has been adopted as a model for other watershed level management programs throughout Manitoba. The program has raised public awareness of fisheries, wildlife, recreation, agriculture and land stewardship issues.
Nitrogen and Phosphorus Removal in a Subsurface-Flow Reed Bed
Authors: Laouali Garba , Brisson Jacques , Dumont Linda , Vincent Gilles 
Published: March 2019

Abstract
During the last decades, there has been a growing concern over phosphorus and nitrogen removal in wastewater treatment systems. Excessive loads of these nutrients have been implicated in the eutrophication of water courses. Although effectiveness of constructed reed beds for primary and secondary wastewater treatments is well established, their capacity for nutrient removal is not as well documented, especially under northern temperate climates. We monitored nutrient removal in the experimental reed bed wastewater treatment of the Biosphère de Montréal, a museum entirely devoted to the important role of water in the ecosystem. Over the first 2 years of operation, nutrient removal during plant growing season averaged 60% for total nitrogen, 53% for Kjeldahl nitrogen, 73% for total phosphorus and 94% for phosphate. Removal remains acceptable in winter despite a slight decrease in efficiency. Nitrification-deni-trification appears to be the main mechanism responsible for nitrogen removal, while precipitation and adsorption account for most of the phosphorus removal.
An Investigation of Public Drinking Fountains and the Changes in Bacterial Colony Counts when Tap Water is Allowed to Flow
Authors: Loving Veronica A. , Burden Robert W. , Loving Anne Lagrange 
Published: March 2019

Abstract
The quality of drinking water is a worldwide concern. Public drinking fountains could contain microbes from the water as well as from the saliva, lips and fingertips of people who have used the fountain. In this study, water samples were collected and cultured for bacteria from 97 public drinking fountains at 0, 5 and 10 seconds after the water was turned on. Overall, this study found that running tap water for 5 seconds significantly decreases the numbers of microbes in the water, as does running it for 10 seconds. However, of the 27 different microbes that were isolated from 291 samples, increased colony counts were noted for many when the water was allowed to flow.
Occurrence and Elimination of Nonylphenol Ethoxylates and Metabolites in Municipal Wastewater and Effluents
Authors: Lee Hing-Biu , Peart Thomas E. 
Published: March 2019

Abstract
A survey of the concentrations of nonylphenol ethoxylates (NPnEO) and their metabolites in wastewater samples collected from a Canadian sewage treatment plant using primary and secondary treatment is presented. Twenty-four-hour composite raw sewage, primary effluent and final effluent samples were collected monthly over a one-year period. Levels of NPnEO (n = 1 to 17) and their metabolites, nonylphenol (NP) and nonylphenoxy carboxylic acids (NPnEC), in these samples were determined by HPLC and GC/MS methods. While ca. 85% of the total alkylphenolics in raw sewage are ethoxylates, the major component (nearly 80%) in the final effluent was in the form of carboxylic acids. During this study period, the median total alkylphenolic concentrations in raw sewage and final effluent were 526 and 248 nmol/L, respectively, representing an overall elimination rate of 53%. The estimated daily discharge of the nonylpheno-lics to the aquatic environment varied from 15 to 44 moles, with a median value of 20 moles. These data suggested that conventional sewage treatments are ineffective in the removal of the surfactant-derived metabolites.
Modélisation hydro-bio-chimique du bassin versant de la rivière Saint-Charles
Authors: Vescovi Luc , Mailhot Alain , Rousseau Alain N. , Villeneuve Jean-Pierre 
Published: March 2019

Abstract
Cet article présente la démarche de modélisation bio-chimique réalisée à l’aide des données existantes sur le bassin versant de la rivière Saint-Charles. L’objectif est de comprendre le comportement global du milieu récepteur de ce bassin versant. La modélisation de la qualité de l’eau avec le modèle QUAL2E est effectuée en considérant un état existant et un ensemble de scénarios. Les incertitudes sur les paramètres de dégradation et les données d’entrée ont fait l’objet d’une analyse de sensibilité. En général, les résultats des simulations de la qualité (DBO et coliformes fécaux) sont satisfaisants pour la partie amont mais pas pour la partie aval de la rivière. Une approche par scénarios a été développée pour mieux équilibrer le bilan des coliformes et de la DBO ainsi que pour estimer la réduction des charges polluantes sur le bassin nécessaire afin d’obtenir une qualité d’eau acceptable en regard des critères de qualité pour activités récréatives. Les résultats suggèrent qu’un ensemble de sources de coliformes et de DBO actuellement non répertoriées sont responsables de la mauvaise qualité de la partie aval de la rivière. L’hypothèse émise est que ces charges polluantes proviennent de fuites du réseau d’égouts.
Potential for Municipal Sewage Sludge Application on Agricultural Lands in Southern Quebec
Authors: Vasseur L , Shipley W , Ansseau C 
Published: March 2019

Abstract
In the present study, sludge composition from 112 municipalities in southern Quebec, Canada, were studied in order to examine the potential of alternative, environmentally sound sludge disposal, such as land application. Twenty-four municipalities with complete data set produced 24,000 dry tons of sludge per year. Of this amount, 47% (11,000 dry tons) could potentially be used for agricultural land application, according to Quebec standards. The other municipalities could not use their sludge for agricultural land application because of heavy metal contamination. The available areas of agricultural lands in southern Quebec are limited to about 149,454 ha. Considering that only 15% of this surface is adequate for sludge application and that a large part is already applied with manure, only 86,683 ha could be used for sludge application. Geographical Information System modeling in a smaller portion of this region showed that another 38% of land must be removed for other reasons, e.g., buffer zones around water bodies and roads. This left a surface area of approximately 54,000 ha or 5.4% of all agricultural land available for sewage sludge application in this region. Land application of sewage sludge may be possible but not without some limitations in some regions of southern Quebec. Other factors, such as pathogens contamination, climatic constraints and economic costs for the transportation and storage of sludge, must also be considered.
Occurrence of Nonylphenol Ethoxylates and Their Metabolites in Canadian Pulp and Paper Mill Effluents and Sludge
Authors: Lee Hing-Biu , Peart Thomas E. 
Published: March 2019

Abstract
A survey of the concentrations of nonylphenol ethoxylates (NPnEO) and their metabolites in the primary and secondary treated effluent and sludge samples collected from pulp and paper mills was conducted. Through the coordination of the Pulp and Paper Research Institute of Canada (PAPRICAN), 19 Canadian and one U.S. mill of various process types and waste treatment methods supplied samples in this study. Previously developed solid-phase extraction, supercritical fluid extraction, high performance liquid chromatography and gas chro-matography/mass spectrometry methods were used for the determination of NPnEO and their metabolites, nonylphenol (NP) and the carboxylates (NPEC), in effluent and sludge samples. The levels of NPnEO ranged from &lt;2 to 129 (median 4.5) µg/L and from &lt;2 to 71.3 (median 5.8) µg/L for the primary and secondary effluents, respectively. The concentrations of NP varied from &lt;0.1 to 1.32 (median 0.35) µg/L in the primary effluent and from &lt;0.1 to 4.32 (median &lt;0.1) µg/L in the secondary effluent. NPECs were found in only one primary and four secondary effluent samples, with an overall concentration range from &lt;1 to 32 µg/L. These results are lower than those reported for paper mill effluents discharged into the lower Fox River, WI, USA. For the pulp and paper mill sludge, the levels of NPnEO and NP, on a dry weight basis, varied from &lt;1 to 90.8 (median 21) µg/g and from &lt;0.05 to 121 (median 1.3) µg/g, respectively. While NPnEO and NP were detected in nearly all sludge, their concentrations were lower than those observed for digested sewage sludge. Again, NPEC were found in only four samples, with an overall range from &lt;1 to 18.5 µg/g. No relationship between the nonylphenolic levels in the effluent samples and the process and waste treatment types of the mill was found.